thunderbolt: Avoid notify PM core about runtime PM resume

Currently we notify PM core about occurred wakes after any resume. This
is not actually needed after resume from runtime suspend. Hence, notify
PM core about occurred wakes only after resume from system sleep. Also,
if the wake occurred in USB4 router upstream port, we don't notify the
PM core about it since it is not actually needed and can cause
unexpected autowake (e.g. if /sys/power/wakeup_count is used).

While there add the missing kernel-doc for tb_switch_resume().

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Constify the struct device_type usage

Since commit aed65af1cc2f ("drivers: make device_type const"), the driver
core can properly handle constant struct device_type. Move the
tb_domain_type, tb_retimer_type, tb_switch_type, usb4_port_device_type,
tb_service_type and tb_xdomain_type variables to be constant structures as
well, placing it into read-only memory which can not be modified at
runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Keep the domain powered when USB4 port is in redrive mode

If a DiplayPort cable is directly connected to the host routers USB4
port, there is no tunnel involved but the port is in "redrive" mode
meaning that it is re-driving the DisplayPort signals from its
DisplayPort source. In this case we need to keep the domain powered on
otherwise once the domain enters D3cold the connected monitor blanks
too.

Since this happens only on Intel Barlow Ridge add a quirk that takes
runtime PM reference if we detect that the USB4 port entered redrive
mode (and release it once it exits the mode).

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Reserve released DisplayPort bandwidth for a group for 10 seconds

The USB4 spec says that the Connection Manager should reserve the
bandwidth that is released in the same group for 10 seconds before it
can be shared with other groups. Add support for this. We also delay the
symmetric transition by that same 10 seconds to avoid any unnecessary
transitions (i.e if the released bandwidth is used by another
DisplayPort tunnel in the same group the link can stay asymmetric the
whole time).

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Reset topology created by the boot firmware

Boot firmware (typically BIOS) might have created tunnels of its own.
The tunnel configuration that it does might be sub-optimal. For instance
it may only support HBR2 monitors so the DisplayPort tunnels it created
may limit Linux graphics drivers. In addition there is an issue on some
AMD based systems where the BIOS does not allocate enough PCIe resources
for future topology extension. By resetting the USB4 topology the PCIe
links will be reset as well allowing Linux to re-allocate.

This aligns the behavior with Windows Connection Manager.

We already issued host router reset for USB4 v2 routers, now extend it
to USB4 v1 routers as well. For pre-USB4 (that's Apple systems) we leave
it as is and continue to discover the existing tunnels.

Suggested-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Sanath S <Sanath.S@amd.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Introduce tb_path_deactivate_hop()

This function can be used to clear path config space of an adapter. Make
it available for other files in this driver.

Signed-off-by: Sanath S <Sanath.S@amd.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Introduce tb_port_reset()

Introduce a function that issues Downstream Port Reset to a USB4 port.
This supports Thunderbolt 2, 3 and USB4 routers.

Signed-off-by: Sanath S <Sanath.S@amd.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Keep link as asymmetric if preferred by hardware

In case of the link is brought up as asymmetric (due to hardware preference), we
honor that and don't transition it to symmetric, unless a router with symmetric
link got plugged below, in the topology (and a bandwidth allows transition to
symmetric).

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move width_name() helper to tb.h

We are going to use it in subsequent patches, so make it available outside of
switch.c. Also, change the name to tb_width_name() to follow the naming
conventions.

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for asymmetric link

USB4 v2 spec defines a Gen 4 link that can operate as an aggregated
symmetric (80/80G) or asymmetric (120/40G). When the link is asymmetric,
the USB4 port on one side of the link operates with three TX lanes and
one RX lane, while the USB4 port on the opposite side of the link
operates with three RX lanes and one TX lane.

Add support for the asymmetric link and provide functions that can be
used to transition the link to asymmetric and back.

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Introduce tb_switch_depth()

This is useful helper to find out the depth of a connected router.
Convert the existing users to call this helper instead of open-coding.

No functional changes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Introduce tb_for_each_upstream_port_on_path()

This is useful when walking over upstream lane adapters over given path.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Introduce tb_port_path_direction_downstream()

Introduce tb_port_path_direction_downstream() to check if path from
source adapter to destination adapter is directed towards downstream.
Convert existing users to call this helper instead of open-coding.

No functional changes.

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Set path power management packet support bit for USB4 v2 routers

USB4 v2 spec allows USB4 links that are part of a pass through tunnel
(such as DisplayPort and USB 3.x Gen T) to enter lower CL states, which
provide better power management. For this USB4 v2 routers in their path
config space of lane 0 adapter include a new bit PMPS (PM packet
support) that needs to be set.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make is_gen4_link() available to the rest of the driver

Rework the function to return the link generation, update the name to
tb_port_get_link_generation(), and make available to the rest of the
driver. This is needed in the subsequent patches.

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make tb_switch_clx_is_supported() static

This function is not used outside of clx.c so make it static. No
functional changes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Get rid of usb4_usb3_port_actual_link_rate()

It turns out there is no need to use the actual link rate when
reclaiming bandwidth for USB 3.x. The reason is that we use consumed
bandwidth which is coming from xHCI when releasing bandwidth (for
example for DisplayPort tunneling) and this can be anything between
1000 Mb/s to maximum, so when reclaiming we can just bump it up back to
maximum instead of actual link rate (which is always <= maximum).

This allows us to get rid of couple of unnecessary lines of code.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Log a warning if device links are not found

The software connection manager needs the device links in order to
establish the tunnels before the native protocols so log a warning if
they are not found.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make bandwidth allocation mode function names consistent

Make sure the DisplayPort bandwidth allocation mode function names are
consistent with the existing ones, such as USB3.

No functional changes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for enhanced uni-directional TMU mode

This is new TMU mode introduced with the USB4 v2. This mode is simpler
than the existing ones and allows all CL states as well. Enable this for
all links where both side routers are v2 and keep the existing
functionality for the v1 and earlier links.

Currently only support the MedRes rate. We can add the HiFi rate later
too if it turns out to be useful.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move constants related to NVM into nvm.c

Move constants related to NVM into nvm.c to make the code cleaner. Use a
separate constant for USB4_DATA_DWORDS in usb4.c.

No functional changes.

Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Enable USB4 v2 PCIe TLP/DLLP extended encapsulation

USB4 v2 spec introduces modified encapsulation of PCIe TLP and DLLP
packets. This improves the PCIe tunneled traffic usage by reducing
overhead. Enable this if both sides of the link support it.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for USB4 v2 80 Gb/s link

USB4 v2 bumps the per-lane speed up to 40 Gb/s. Also the lanes are
always bonded which gives 80 Gb/s symmetric link (and 120/40 Gb/s
asymmetric). This updates the speed and width of routers and XDomain
connections to support the Gen 4 link. For now we keep the link as is
even if it is already asymmetric.

While there make tb_port_set_link_width() static.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Identify USB4 v2 routers

Add a new function usb4_switch_version() that can be used to figure out
the spec version of the router and make tb_switch_is_usb4() to use it as
well. Update the uevent accordingly.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Enable/disable sideband depending on USB4 port offline mode

When USB4 port is in offline mode (this mean there is no device
attached) we want to keep the sideband up to make it possible to
communicate with the retimers. In the same way there is no need to
enable sideband transactions when the USB4 port is not offline as they
are already up.

For this reason make the enabling/disabling depend on the USB4 port
offline status.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Initialize CL states from the hardware

In case the boot firmware enabled any of them, read the currently
configured CL states and update the router structure accordingly.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Switch CL states from enum to a bitmask

This is more natural and follows the hardware register layout better.
This makes it easier to see which CL states we enable (even though they
should be enabled together). Rename 'clx_mask' to 'clx' everywhere as
this is now always bitmask.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move CLx support functions into clx.c

There really don't belong to switch.c so move them into their own file.
As we do this rename the functions to match the conventions used
elsewhere in the driver.

No functional changes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Check valid TMU configuration in tb_switch_tmu_configure()

Instead of at enable time we can do this already in
tb_switch_tmu_configure().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Get rid of tb_switch_enable_tmu_1st_child()

This is better to be part of the software connection manager flows in
tb.c. Also name the new function tb_increase_tmu_accuracy() to match
what it actually does.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Drop useless 'unidirectional' parameter from tb_switch_tmu_is_enabled()

There is no point passing it as we already have a field for that. While
there clean up the kernel-doc of things that do not really belong to the
API documentation (these can be figured out from the spec itself).

No functional changes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Introduce tb_xdomain_downstream_port()

In the same way we did for the routers add a function that returns the
parent routers downstream facing port for XDomain devices.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Introduce tb_switch_downstream_port()

Introduce tb_switch_downstream_port() helper function that returns the
downstream port of a parent switch that is connected to the upstream
port of specified switch. From now on, we use it all across the driver
where applicable.

While there fix a whitespace in comment and rename 'downstream' to
'down' to be consistent with the rest of the driver.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Limit USB3 bandwidth of certain Intel USB4 host routers

Current Intel USB4 host routers have hardware limitation that the USB3
bandwidth cannot go higher than 16376 Mb/s. Work this around by adding a
new quirk that limits the bandwidth for the affected host routers.

Cc: stable@vger.kernel.org
Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add missing UNSET_INBOUND_SBTX for retimer access

According to USB4 retimer specification, the process of firmware update
sequence requires issuing a SET_INBOUND_SBTX port operation that later
shall be followed by UNSET_INBOUND_SBTX port operation. This last step
is not currently issued by the driver but it is necessary to make sure
the retimers are put back to passthrough mode even during enumeration.

If this step is missing the link may not come up properly after
soft-reboot for example.

For this reason issue UNSET_INBOUND_SBTX after SET_INBOUND_SBTX for
enumeration and also when the NVM upgrade is run.

Reported-by: Christian Schaubschläger <christian.schaubschlaeger@gmx.at>
Link: https://lore.kernel.org/linux-usb/b556f5ed-5ee8-9990-9910-afd60db93310@gmx.at/
Cc: stable@vger.kernel.org
Signed-off-by: Gil Fine <gil.fine@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add quirk to disable CLx

Add QUIRK_NO_CLX to disable the CLx state for hardware which
doesn't supports it.

AMD Yellow Carp and Pink Sardine don't support CLx state,
hence disabling it using QUIRK_NO_CLX.

Cc: stable@vger.kernel.org
Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
[mw: added debug log when the quirk is run]
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

driver core: make struct device_type.uevent() take a const *

The uevent() callback in struct device_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andreas Noever <andreas.noever@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bard Liao <yung-chuan.liao@linux.intel.com>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jilin Yuan <yuanjilin@cdjrlc.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Mark Gross <markgross@kernel.org>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Maximilian Luz <luzmaximilian@gmail.com>
Cc: Michael Jamet <michael.jamet@intel.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Sanyog Kale <sanyog.r.kale@intel.com>
Cc: Sean Young <sean@mess.org>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Won Chung <wonchung@google.com>
Cc: Yehezkel Bernat <YehezkelShB@gmail.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for Thunderbolt
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Wolfram Sang <wsa@kernel.org>
Acked-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for DisplayPort bandwidth allocation mode

The USB4 spec defines an optional feature that allows the connection
manager to negotiate with the graphics through DPCD registers changes in
the bandwidth allocation dynamically. This is referred as "bandwidth
allocation mode" in the spec. The connection manager uses DP IN adapters
registers to communicate with the graphics, and also gets notifications
from these adapters when the graphics wants to change the bandwidth
allocation. Both the connection manager and the graphics driver needs to
support this.

We check if the DP IN adapter supports this and if it does enable it
before establishing a DP tunnel. Then we react on DP_BW notifications
coming from the DP IN adapter and update the bandwidth allocation
accordingly (within the maximum common capabilities the DP IN/OUT
support).

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add functions to support DisplayPort bandwidth allocation mode

USB4 spec defines an additional feature that DP IN adapters can
implement (alongside with the graphics DPCD register set) to support
more dynamic bandwidth management for DisplayPort tunnels. For the
connection manager the communication happens through the DP IN adapter
using a set of registers in the adapter config space allocated for this.
Add functions that export this functionality for the rest of the driver.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Use correct type in tb_port_is_clx_enabled() prototype

tb_port_is_clx_enabled() generates a valid warning with gcc-13:
drivers/thunderbolt/switch.c:1286:6: error: conflicting types for 'tb_port_is_clx_enabled' due to enum/integer mismatch; have 'bool(struct tb_port *, unsigned int)' ...
drivers/thunderbolt/tb.h:1050:6: note: previous declaration of 'tb_port_is_clx_enabled' with type 'bool(struct tb_port *, enum tb_clx)' ...

I.e. the type of the 2nd parameter of tb_port_is_clx_enabled() in the
declaration is unsigned int, while the definition spells enum tb_clx.
Synchronize them to the former as the parameter is in fact a mask of the
enum values.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Explicitly enable lane adapter hotplug events at startup

Software that has run before the USB4 CM in Linux runs may have disabled
hotplug events for a given lane adapter.

Other CMs such as that one distributed with Windows 11 will enable hotplug
events. Do the same thing in the Linux CM which fixes hotplug events on
"AMD Pink Sardine".

Cc: stable@vger.kernel.org
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move vendor specific NVM handling into nvm.c

As there will be more USB4 devices that support NVM firmware upgrade from
various vendors, it makes sense to split out the Intel specific NVM
image handling from the generic code. This moves the Intel specific NVM
handling into a new structure that will be matched by the device type
and the vendor ID. Do this for both routers and retimers.

This makes it easier to extend the NVM support to cover new vendors and
NVM image formats in the future.

Signed-off-by: Szuying Chen <Chloe_Chen@asmedia.com.tw>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Provide tb_retimer_nvm_read() analogous to tb_switch_nvm_read()

As we are moving the NVM vendor specifics into nvm.c we need to deal
witht he retimer NVM formats too. For this reason provide retimer
specific function that can be used to read the contents of the NVM and
rename the internal ones accordingly analogous to what we do with
routers.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Rename and make nvm_read() available for other files

In order to support non-Intel NVM formats the vendor specific NVM
validation code that will live in nvm.c needs to be able to read various
parts of the NVM so make the function available outside of switch.c and
rename it accordingly.

Signed-off-by: Szuying Chen <Chloe_Chen@asmedia.com.tw>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Extend NVM version fields to 32-bits

In order to support non-Intel NVM image formats extend the NVM major and
minor version to 32-bits to better accommondate different versioning
schemes.

No functional impact.

Signed-off-by: Szuying Chen <Chloe_Chen@asmedia.com.tw>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for receiver lane margining

USB4 spec defines standard set of registers to be used for receiver lane
margining. This is useful for I/O interface quality and electrical
robustness validation during manufacturing. Expose receiver lane
margining through new debugfs directory "margining" that is added under
each connected USB4 port. Users can then run the margining by writing to
the exposed attributes under that directory.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add helper to check if CL states are enabled on port

We will need this when enabling lane margining support.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Pass CL state bitmask to tb_port_clx_supported()

Instead of testing just a single CL state we can pass a bitmask of
states to check. This makes it simpler for callers of the function.

We also add a check for CL2 even though not fully supported by the
driver yet.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move tb_xdomain_parent() to tb.h

We are going to need this for lane margining support so make it
available outside of xdomain.c.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Show link type for XDomain connections too

Following what we do for routers already, extend this to XDomain
connections as well. This will show in sysfs whether the link is in USB4
or Thunderbolt mode.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

thunderbolt: Change TMU mode to HiFi uni-directional once DisplayPort tunneled

Here we configure TMU mode to HiFi uni-directional once DP tunnel
is created. This is due to accuracy requirement for DP tunneling
as appears in CM guide 1.0, section 7.3.2.
Due to Intel hardware limitation, once we changed the TMU mode to HiFi
uni-directional (when DP tunnel exists), we don't change TMU mode back to
normal uni-directional, even if DP tunnel is torn down later.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add CL1 support for USB4 and Titan Ridge routers

In this patch we add support for a second low power state of the link: CL1.
Low power states (called collectively CLx) are used to reduce
transmitter and receiver power when a high-speed lane is idle.
We enable it, if both sides of the link support it,
and only for the first hop router (i.e. the first device that connected
to the host router). This is needed for better thermal management.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: test: Use kunit_test_suite() macro

The new implementation of kunit_test_suite() for modules no longer
conflicts with module_init, so can now be used by the thunderbolt tests.

Also update the Kconfig entry to enable the test when KUNIT_ALL_TESTS is
enabled.

This means that kunit_tool can now successfully run and parse the test
results with, for example:
./tools/testing/kunit/kunit.py run --arch=x86_64 \
--kconfig_add CONFIG_PCI=y --kconfig_add CONFIG_USB4=y \
'thunderbolt'

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Daniel Latypov <dlatypov@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

thunderbolt: Split setting link width and lane bonding into own functions

When bonding lanes over XDomain the host that has "higher" UUID triggers
link re-train for bonding, and the host that has "lower" UUID just waits
for this to happen. To support this split setting the link width and
triggering the actual bonding a separate functions that can be called as
needed.

While there remove duplicated empty line in the kernel-doc comment of
tb_port_lane_bonding_disable().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move tb_port_state() prototype to correct place

This should be before tb_wait_for_port() following how the functions in
switch.c are organized.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Use decimal number with port numbers

This makes it consistent with the other logging functions.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Brad Campbell <lists2009@fnarfbargle.com>

thunderbolt: Add internal xHCI connect flows for Thunderbolt 3 devices

Both Alpine Ridge and Titan Ridge require special flows in order to
activate the internal xHCI controller when there is USB device connected
to the downstream type-C port. This implements the missing flows for
both.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add missing device ID to tb_switch_is_alpine_ridge()

tb_switch_is_alpine_ridge() is missing device ID for Intel Alpine Ridge
dual port version so add this.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Enable CL0s for Intel Titan Ridge

Low power link states (called collectively CLx) are used to reduce
transmitter and receiver power when a high-speed lane is idle. The
simplest one being called CL0s. Follow what we already do for USB4
device routers and enable CL0s for Intel Titan Ridge device router too.
This allows better thermal management.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Implement TMU time disruption for Intel Titan Ridge

Intel Titan Ridge based routers have slightly different flow for time
disruption than USB4 compliant routers. This makes it work on Titan
Ridge too. Needed to enable link low power states on Titan Ridge.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move usb4_switch_wait_for_bit() to switch.c

Currently usb4_switch_wait_for_bit() used only in usb4.c Moving to
switch.c to call it from other files. Also change the prefix to "tb_"
to follow to the naming convention.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add CL0s support for USB4 routers

In this patch we add enabling of CL0s - a low power state of the link.
Low power states (called collectively CLx) are used to reduce
transmitter and receiver power when a high-speed lane is idle. For now,
we add support only for first low power state: CL0s. We enable it, if
both sides of the link support it, and only for the first hop router.
(i.e. the first device that connected to the host router). This is
needed for better thermal management.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add TMU uni-directional mode

Up until Titan Ridge (Thunderbolt 3) device routers only supported
bi-directional mode. In this patch we add to TMU a uni-directional mode.
The uni-directional mode is needed for enabling of low power state of
the link (CLx).

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Tear down existing tunnels when resuming from hibernate

If the boot firmware implements connection manager of its own it may not
create the paths in the same way or order we do. For example it may
create first PCIe tunnel and then USB3 tunnel. When we restore our
tunnels (first de-activating them) we may be doing that over completely
different tunnels and that leaves them possibly non-functional. For this
reason we re-use the tunnel discovery functionality and find out all the
existing tunnels, and tear them down. Once that is done we can restore
our tunnels.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add WRITE_ONLY and AUTHENTICATE_ONLY NVM operations for retimers

The same way we support these two operations for USB4 routers we can
extend the retimer NVM operations to support retimers also.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Allow router NVM authenticate separately

It may be useful if the actual NVM authentication can be delayed to be
run later, for instance when the user logs out. For this reason add a
new NVM operation (AUHENTICATE_ONLY) that just triggers the authentication
procedure over whatever was written to the NVM storage.

This is not supported with Thunderbolt 1-3 devices, though.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Move nvm_write_ops to tb.h

Currently these write ops are used for updating router firmware images
only. Moving to tb.h helps the retimers also to use the same ops.

Also add tb_ prefix to the enum while there.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for retimer NVM upgrade when there is no link

With help from platform firmware (ACPI) it is possible to power on
retimers even when there is no USB4 link (e.g nothing is connected to
the USB4 ports). This allows us to bring the USB4 sideband up so that we
can access retimers and upgrade their NVM firmware.

If the platform has support for this, we expose two additional
attributes under USB4 ports: offline and rescan. These can be used to
bring the port offline, rescan for the retimers and put the port online
again. The retimer NVM upgrade itself works the same way than with cable
connected.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add additional USB4 port operations for retimer access

When accessing retimers when there is no cable connected we are going to
need additional USB4 port operations. First the port needs to be put
into offline mode, and then the sideband channel transactions must be
enabled on the SBTX line. This adds support for these operations.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for ACPI _DSM to power on/off retimers

Typically retimers can be accessed only when the USB4 link is up (e.g
there is a cable connected). However, sometimes it is useful to be able
to access retimers even if there is nothing connected to the USB4 port.
For instance we may still want to be able to upgrade the retimer NVM
firmware even if the user does not have any USB4 devices. This is
something that USB4 spec leaves to implementers.

In case of ACPI based systems, we can support this by providing a
special _DSM method under each USB4 port. This _DSM can be used to turn
on power to on-board retimers (and cycle it through different modes so
that the sideband becomes usable).

This patch adds support for this _DSM and makes the functionality
available to the rest of the driver through tb_acpi_power_[on|off]_retimers().

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add USB4 port devices

Create devices for each USB4 port. This is needed when we add retimer
access when there is no device connected but may be useful for other
purposes too following what USB subsystem does. This exports a single
attribute "link" that shows the type of the USB4 link (or "none" if
there is no cable connected).

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Allocate credits according to router preferences

The USB4 Connection Manager guide provides detailed information how the
USB4 router buffer (credit) allocation information should be used by the
connection manager when it allocates buffers for different paths. This
patch implements it for Linux. For USB 3.x and DisplayPort we use
directly the router preferences. The rest of the buffer space is then
used for PCIe and DMA (peer-to-peer, XDomain) traffic. DMA tunnels
require at least one buffer and PCIe six, so if there is not enough
buffers we fail the tunnel creation.

For the legacy Thunderbolt 1-3 devices we use the existing hard-coded
scheme except for DMA where we use the values suggested by the USB4 spec
chapter 13.

Co-developed-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Update port credits after bonding is enabled/disabled

Once lane bonding has been enabled (or disabled) both lane adapters may
update their total credits accordingly. For this reason re-read the port
credits after lane bonding has been enabled or disabled.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Read router preferred credit allocation information

USB4 routers must expose their preferred credit (buffer) allocation
information through router operation. This information tells the
connection manager how the router prefers its buffers to be allocated to
get the expected bandwidth for the supported protocols.

Read this information and store it as part of struct tb_switch for each
USB4 router.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Wait for the lanes to actually bond

It may take some time until the two lanes enter bonded state so poll for
the link width to match what is expected before going forward. This ensures
the link is in expected state before we start establishing paths through
it.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move nfc_credits field to struct tb_path_hop

With the USB4 buffer allocation the number of credits (and non-flow
credits) may be different depending on the router buffer allocation
preferences. To allow this move the nfc_credits field to struct
tb_path_hop.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add wake from DisplayPort

Latest USB4 spec added a new wake bit for DisplayPort so add this to the
driver when runtime suspending. This way wake up the domain when a new
monitor is plugged in to any of the device routers.

Also do the same for pre-USB4 devices through the link controller
registers as documented in chapter 13 of the USB4 spec.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Split NVM read/write generic functions out from usb4.c

We do this for Thunderbolt 2/3 devices through DMA port, USB4 devices
and retimers pretty much the same way. Only the actual block read/write
is different. For this reason split out the NVM read/write functions
from usb4.c to nvm.c and make USB4 device code call these when needed.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Allow multiple DMA tunnels over a single XDomain connection

Currently we have had an artificial limitation of a single DMA tunnel
per XDomain connection. However, hardware wise there is no such limit
and software based connection manager can take advantage of all the DMA
rings available on the host to establish tunnels.

For this reason make the tb_xdomain_[enable|disable]_paths() to take the
DMA ring and HopID as parameter instead of storing them in the struct
tb_xdomain. We also add API functions to allocate input and output
HopIDs of the XDomain connection that the service drivers can use
instead of hard-coding.

Also convert the two existing service drivers over to this API.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Drop unused tb_port_set_initial_credits()

This function is not used anymore in the driver so we can remove it.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Decrease control channel timeout for software connection manager

When the firmware connection manager is not proxying between the
software and the hardware we can decrease the timeout for control
packets significantly. The USB4 spec recommends 10 ms +- 1 ms but we use
slightly larger value (100 ms) which is recommendation from Intel
Thunderbolt firmware folks. When firmware connection manager is running
then we keep using the existing 5000 ms.

To implement this we move the control channel allocation to
tb_domain_alloc(), and pass the timeout from that function to the
tb_ctl_alloc(). Then make both connection manager implementations pass
the timeout when they alloc the domain structure.

While there update kernel-doc of struct tb_ctl to match the reality.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Drop unused functions tb_switch_is_[ice|tiger]_lake()

Drop the two functions not used anymore in the driver.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for native USB4 _OSC

ACPI 6.4 introduced a new _OSC capability used to negotiate whether the
OS is supposed to use Software (native) or Firmware based Connection
Manager. If the native support is granted then there are set of bits
that enable/disable different tunnel types that the Software Connection
Manager is allowed to tunnel.

This adds support for this new USB4 _OSC accordingly. When PCIe
tunneling is disabled then the driver switches security level to be
"nopcie" following the security level 5 used in Firmware based
Connection Manager.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>

thunderbolt: Allow disabling XDomain protocol

This allows disabling XDomain protocol completely if the user does not
plan to use the USB4/Thunderbolt peer-to-peer functionality, or for
security reasons.

XDomain protocol is enabled by default but with this commit it is
possible to disable it by passing "xdomain=0" as module parameter (or
through the kernel command line).

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>

thunderbolt: Add clarifying comments about USB4 terms router and adapter

USB4 spec talks about routers and adapters whereas Thunderbolt 1-3
talked about CIO (Converged I/O) switches and ports. These are the same
thing but might cause confusion so add clarifying comments to struct
tb_switch and struct tb_port about the USB4 terms.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for de-authorizing devices

In some cases it is useful to be able de-authorize devices. For example
if user logs out the userspace can have a policy that disconnects PCIe
devices until logged in again. This is only possible for software based
connection manager as it directly controls the tunnels.

For this reason make the authorized attribute accept writing 0 which
makes the software connection manager to tear down the corresponding
PCIe tunnel. Userspace can check if this is supported by reading a new
domain attribute deauthorization, that holds 1 in that case.

While there correct tb_domain_approve_switch() kernel-doc and
description of authorized attribute to mention that it is only about
PCIe tunnels.

Cc: Christian Kellner <christian@kellner.me>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>

thunderbolt: Start lane initialization after sleep

USB4 spec says that for TBT3 compatible device routers the connection
manager needs to set SLI (Start Lane Initialization) to get the lanes
that were not connected back to functional state after sleep. Same needs
to be done if the link was XDomain.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>

thunderbolt: Add connection manager specific hooks for USB4 router operations

Intel USB4 host routers that run the firmware based connection manager
(ICM) may implement a proxy for USB4 router operations. This is to avoid
the firmware to race with the OS driver, as both may need to run these
operations.

This adds two new connection manager specific callbacks which, if
provided, get called instead of the native USB4 router operation.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Perform USB4 router NVM upgrade in two phases

The currect code expects that the router returns back the status of the
NVM authentication immediately. When tested against a real USB4 device
what happens is that the router is reset and only after that the result
is updated in the ROUTER_CS_26 register status field. This also seems to
align better what the spec suggests.

For this reason do the same what we already do with the Thunderbolt 3
devices and perform the NVM upgrade in two phases. First start the
NVM_AUTH router operation and once the router is added back after the
reset read the status in ROUTER_CS_26 and expose it to the userspace
accordingly.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Create debugfs directory automatically for services

This allows service drivers to use it as parent directory if they need
to add their own debugfs entries.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add functions for enabling and disabling lane bonding on XDomain

These can be used by service drivers to enable and disable lane bonding
as needed.

Signed-off-by: Isaac Hazan <isaac.hazan@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add link_speed and link_width to XDomain

Link speed and link width are needed for checking expected values in
case of using a loopback service.

Signed-off-by: Isaac Hazan <isaac.hazan@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for Intel Tiger Lake-H

Intel Tiger Lake-H has the same Thunderbolt/USB4 controller as Tiger
Lake-LP. Add the Tiger Lake-H PCI IDs to the driver list of supported
devices.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Capitalize comment on top of QUIRK_FORCE_POWER_LINK_CONTROLLER

To keep it consistent with the other single line comments in the driver.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Allow KUnit tests to be built also when CONFIG_USB4=m

This adds a bit more build coverage for the tests even though these are
not expected to be enabled by normal users and distros. In order to make
this working we need to open-code kunit_test_suite() and call the
relevant functions directly in the driver init/exit hook.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Only stop control channel when entering freeze

According to the kernel power management documentation freeze phase
should only quiesce the device, no need to configure wakes or put it to
low power state. For this reason we simply stop the control channel and
in case of Software Connection Manager also mark the hotplug disabled.
This should align the driver better with the PM framework expectations.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add debugfs interface

This adds debugfs interface that can be used for debugging possible
issues in hardware/software. It exposes router and adapter config spaces
through files like this:

/sys/kernel/debug/thunderbolt/<DEVICE>/regs
/sys/kernel/debug/thunderbolt/<DEVICE>/<PORT1>/regs
/sys/kernel/debug/thunderbolt/<DEVICE>/<PORT1>/path
/sys/kernel/debug/thunderbolt/<DEVICE>/<PORT1>/counters
/sys/kernel/debug/thunderbolt/<DEVICE>/<PORT2>/regs
/sys/kernel/debug/thunderbolt/<DEVICE>/<PORT2>/path
/sys/kernel/debug/thunderbolt/<DEVICE>/<PORT2>/counters
...

The "regs" is either the router or port configuration space register
dump. The "path" is the port path configuration space and "counters" is
the optional counters configuration space.

These files contains one register per line so it should be easy to use
normal filtering tools to find the registers of interest if needed.

The router and adapter regs file becomes writable when
CONFIG_USB4_DEBUGFS_WRITE is enabled (which is not supposed to be done
in production systems) and in this case the developer can write "offset
value" lines there to modify the hardware directly. For convenience this
also supports the long format the read side produces (but ignores the
additional fields). The counters file can be written even when
CONFIG_USB4_DEBUGFS_WRITE is not enabled and it is only used to clear
the counter values.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Introduce tb_switch_is_tiger_lake()

This is needed to differentiate Tiger Lake from other controllers.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Introduce tb_switch_is_ice_lake()

This is needed to differentiate Ice Lake from other controllers.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Check for Intel vendor ID when identifying controller

With USB4 there will be other vendors so make sure the current checks
for different Intel controllers will not accidentally match those.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Introduce tb_port_is_nhi()

This is useful if one needs to check if adapter (port) is the host
interface (NHI). Make tb_port_alloc_hopid() take advantage of this.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Introduce tb_switch_next_cap()

This is similar to tb_port_next_cap() but instead allows walking
capability list of a switch (router). Convert tb_switch_find_cap() and
tb_switch_find_vse_cap() to use this as well.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Introduce tb_port_next_cap()

This function is useful for walking port config space (adapter)
capability lists. Convert the tb_port_find_cap() to use this as well.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add runtime PM for Software CM

This adds runtime PM support for the Software Connection Manager parts
of the driver. This allows to save power when either there is no device
attached at all or there is a device attached and all following
conditions are true:

- Tunneled PCIe root/downstream ports are runtime suspended
- Tunneled USB3 ports are runtime suspended
- No active DisplayPort stream
- No active XDomain connection

For the first two we take advantage of device links that were added in
previous patch. Difference for the system sleep case is that we also
enable wakes when something is geting plugged in/out of the Thunderbolt
ports.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Create device links from ACPI description

The new way to describe relationship between tunneled ports and USB4 NHI
(Native Host Interface) is with ACPI _DSD looking like below for a PCIe
downstream port:

Scope (\_SB.PCI0)
{
Device (NHI0) { } // Thunderbolt NHI

Device (DSB0) // Hotplug downstream port
{
Name (_DSD, Package () {
ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
Package () {
Package () {"usb4-host-interface", \_SB.PCI0.NHI0},
...
}
})
}
}

This is "documented" in these [1] USB-IF slides and being used on
systems that ship with Windows.

The _DSD can be added to tunneled USB3 and PCIe ports, and is needed to
make sure the USB4 NHI is resumed before any of the tunneled ports so
the protocol tunnels get established properly before the actual port
itself is resumed. Othwerwise the USB/PCI core find the link may not be
established and starts tearing down the device stack.

This parses the ACPI description each time NHI is probed and tries to
find devices that has the property and it references the NHI in
question. For each matching device a device link from that device to the
NHI is created.

Since USB3 ports themselves do not get runtime suspended with the parent
device (hub) we do not add the link from the USB3 port to USB4 NHI but
instead we add the link from the xHCI device. This makes the device link
usable for runtime PM as well.

[1] https://www.usb.org/sites/default/files/D1T2-2%20-%20USB4%20on%20Windows.pdf

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

thunderbolt: Enable wakes from system suspend

In order for the router and the whole domain to wake up from system
suspend states we need to enable wakes for the connected routers. For
device routers we enable wakes from PCIe and USB 3.x. This allows
devices such as keyboards connected to USB 3.x hub that is tunneled to
wake the system up as expected. For all routers we enabled wake on USB4
for each connected ports. This is used to propagate the wake from router
to another.

Do the same for legacy routers through link controller vendor specific
registers as documented in USB4 spec chapter 13.

While there correct kernel-doc of usb4_switch_set_sleep() -- it does not
enable wakes instead there is a separate function (usb4_switch_set_wake())
that does.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Disable lane 1 for XDomain connection

USB4 spec mandates that the lane 1 should be disabled if lanes are not
bonded. For host-to-host connections (XDomain) we don't support lane
bonding so in order to be compatible with the spec, disable lane 1 when
another host is connected.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Configure port for XDomain

When the port is connected to another host it should be marked as such
in the USB4 port capability. This information is used by the router
during sleep and wakeup.

Also do the same for legacy switches via link controller vendor specific
registers.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Set port configured for both ends of the link

Both ends of the link needs to have this set. Otherwise the link is not
re-established properly after sleep. Now since it is possible to have
mixed USB4 and Thunderbolt 1, 2 and 3 devices we need to split the link
configuration functionality to happen per port so we can pick the
correct implementation.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Configure link after lane bonding is enabled

During testing it was noticed that the link is not properly restored
after the domain exits sleep if the link configured bits are set before
lane bonding is enabled. The USB4 spec does not say in which order these
need to be set but setting link configured afterwards makes the link
restoration work so we do that instead.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Send reset only to first generation routers

First generation routers may need the reset command upon resume but it
is not supported by newer generations.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Disable ports that are not implemented

Commit 4caf2511ec49 ("thunderbolt: Add trivial .shutdown") exposes a bug
in the Thunderbolt driver, that frees an unallocated id, resulting in the
following spinlock bad magic bug.

[ 20.633803] BUG: spinlock bad magic on CPU#4, halt/3313
[ 20.640030] lock: 0xffff92e6ad5c97e0, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
[ 20.672139] Call Trace:
[ 20.675032] dump_stack+0x97/0xdb
[ 20.678950] ? spin_bug+0xa5/0xb0
[ 20.682865] do_raw_spin_lock+0x68/0x98
[ 20.687397] _raw_spin_lock_irqsave+0x3f/0x5d
[ 20.692535] ida_destroy+0x4f/0x124
[ 20.696657] tb_switch_release+0x6d/0xfd
[ 20.701295] device_release+0x2c/0x7d
[ 20.705622] kobject_put+0x8e/0xac
[ 20.709637] tb_stop+0x55/0x66
[ 20.713243] tb_domain_remove+0x36/0x62
[ 20.717774] nhi_remove+0x4d/0x58

Fix the issue by disabling ports that are enabled as per the EEPROM, but
not implemented. While at it, update the kernel doc for the disabled
field, to reflect this.

Cc: stable@vger.kernel.org
Fixes: 4caf2511ec49 ("thunderbolt: Add trivial .shutdown")
Reported-by: Srikanth Nandamuri <srikanth.nandamuri@intel.com>
Signed-off-by: Nikunj A. Dadhania <nikunj.dadhania@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for authenticate on disconnect

Some external devices can support completing thunderbolt authentication
when they are unplugged. For this to work though, the link controller must
remain operational.

The only device known to support this right now is the Dell WD19TB, so add
a quirk for this.

Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for separating the flush to SPI and authenticate

This allows userspace to have a shorter period of time that the device
is unusable and to call it at a more convenient time.

For example flushing the image may happen while the user is using the
machine and authenticating/rebooting may happen while logging out.

Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for on-board retimers

USB4 spec specifies standard access to retimers (both on-board and
cable) through USB4 port sideband access. This makes it possible to
upgrade their firmware in the same way than we already do with the
routers.

This enumerates on-board retimers under each USB4 port when the link
comes up and adds them to the bus under the router the retimer belongs
to. Retimers are exposed in sysfs with name like <device>:<port>.<index>
where device is the router the retimer belongs to, port is the USB4 port
the retimer is connected to and index is the retimer index under that
port (starting from 1). This applies to the upstream USB4 port as well
so if there is on-board retimer between the port and the router it is
also added accordingly.

At this time we do not add cable retimers but there is no techincal
restriction to do so in the future if needed. It is not clear whether it
makes sense to upgrade their firmwares and at least Thunderbolt 3 cables
it has not been done outside of lab environments.

The sysfs interface is made to follow the router NVM upgrade to make it
easy to extend the existing userspace (fwupd) to handle these as well.

Signed-off-by: Kranthi Kuntala <kranthi.kuntala@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Implement USB4 port sideband operations for retimer access

USB4 spec specifies standard set of sideband operations that are send
over the low speed link to access either retimers on the link or the
link parter (the other router). The USB4 retimer spec extends these and
adds operations for retimer NVM upgrade.

This implements the retimer access and NVM upgrade USB4 port sideband
operations which we need for retimer support in the patch that follows.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Split common NVM functionality into a separate file

We are going to reuse some of this functionality to implement retimer
NVM upgrade so move common NVM functionality into its own file. We also
rename the structure from tb_switch_nvm to tb_nvm to make it clear that
it is not just for switches.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add USB3 bandwidth management

USB3 supports both isochronous and non-isochronous traffic. The former
requires guaranteed bandwidth and can take up to 90% of the total
bandwidth. With USB4 USB3 is tunneled over USB4 fabric which means that
we need to make sure there is enough bandwidth allocated for the USB3
tunnels in addition to DisplayPort tunnels.

Whereas DisplayPort bandwidth management is static and done before the
DP tunnel is established, the USB3 bandwidth management is dynamic and
allows increasing and decreasing the allocated bandwidth according to
what is currently consumed. This is done through host router USB3
downstream adapter registers.

This adds USB3 bandwidth management to the software connection manager
so that we always try to allocate maximum bandwidth for DP tunnels and
what is left is allocated for USB3.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make tb_port_get_link_speed() available to other files

We need to call this from tb.c when we improve the bandwidth management
to take USB3 into account.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Implement USB3 bandwidth negotiation routines

Each host router USB3 downstream adapter has a set of registers that are
used to negotiate bandwidth between the connection manager and the
internal xHCI controller. These registers allow dynamic bandwidth
management for USB3 isochronous traffic based on what is actually
consumed vs. allocated at any given time.

Implement these USB3 bandwidth negotiation routines to allow the
software connection manager take advantage of these.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Do not tunnel USB3 if link is not USB4

USB3 tunneling is possible only over USB4 link so don't create USB3
tunnels if that's not the case.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Increase path length in discovery

Currently we have only supported paths that follow daisy-chain topology
but USB4 also allows to build trees of devices. For this reason increase
maximum path length we use for discovery to be from the lowest level to
the host router and back to the same level.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make tb_path_alloc() work with tree topologies

With USB4, topologies are not limited to daisy-chains anymore so when
calculating how many hops are between two ports we need to walk the
whole path instead.

Add helper function tb_for_each_port_on_path() that can be used to walk
over each port on a path and make tb_path_alloc() to use it.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for USB 3.x tunnels

USB4 added a capability to tunnel USB 3.x protocol over the USB4
fabric. USB4 device routers may include integrated SuperSpeed HUB or a
function or both. USB tunneling follows PCIe so that the tunnel is
created between the parent and the child router from USB3 downstream
adapter port to USB3 upstream adapter port over a single USB4 link.

This adds support for USB 3.x tunneling and also capability to discover
existing USB 3.x tunnels (for example created by connection manager in
boot firmware).

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20191217123345.31850-9-mika.westerberg@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for Time Management Unit

Time Management Unit (TMU) is included in each USB4 router. It is used
to synchronize time across the USB4 fabric. By default when USB4 router
is plugged to the domain, its TMU is turned off. This differs from
Thunderbolt (1, 2 and 3) devices whose TMU is by default configured to
bi-directional HiFi mode. Since time synchronization is needed for
proper Display Port tunneling this means we need to configure the TMU on
USB4 compliant devices.

The USB4 spec allows some flexibility on how the TMU can be configured.
This makes it possible to enable link power management states (CLx) in
certain topologies, where for example DP tunneling is not used. TMU can
also be re-configured dynamicaly depending on types of tunnels created
over the USB4 fabric.

In this patch we simply configure the TMU to be in bi-directional HiFi
mode. This way we can tunnel any kind of traffic without need to perform
complex steps to re-configure the domain dynamically. We can add more
fine-grained TMU configuration later on when we start enabling CLx
states.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Co-developed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20191217123345.31850-8-mika.westerberg@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Make tb_switch_find_cap() available to other files

We need to find switch capabilities in order to implement TMU support so
make it available to other files as well.

Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20191217123345.31850-7-mika.westerberg@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add initial support for USB4

USB4 is the public specification based on Thunderbolt 3 protocol. There
are some differences in register layouts and flows. In addition to PCIe
and DP tunneling, USB4 supports tunneling of USB 3.x. USB4 is also
backward compatible with Thunderbolt 3 (and older generations but the
spec only talks about 3rd generation). USB4 compliant devices can be
identified by checking USB4 version field in router configuration space.

This patch adds initial support for USB4 compliant hosts and devices
which enables following features provided by the existing functionality
in the driver:

- PCIe tunneling
- Display Port tunneling
- Host and device NVM firmware upgrade
- P2P networking

This brings the USB4 support to the same level that we already have for
Thunderbolt 1, 2 and 3 devices.

Note the spec talks about host and device "routers" but in the driver we
still use term "switch" in most places. Both can be used interchangeably.

Co-developed-by: Rajmohan Mani <rajmohan.mani@intel.com>
Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20191217123345.31850-5-mika.westerberg@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Make tb_find_port() available to other files

We will be needing this when adding initial USB4 support so make it
available to other files in the driver as well. We also rename it to
tb_switch_find_port() to follow conventions used in switch.c.

No functional changes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20191217123345.31850-2-mika.westerberg@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add bandwidth management for Display Port tunnels

Titan Ridge supports Display Port 1.4 which adds HBR3 (High Bit Rate)
rates that may be up to 8.1 Gb/s over 4 lanes. This translates to
effective data bandwidth of 25.92 Gb/s (as 8/10 encoding is removed by
the DP adapters when going over Thunderbolt fabric). If another high
rate monitor is connected we may need to reduce the bandwidth it
consumes so that it fits into the total 40 Gb/s available on the
Thunderbolt fabric.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add Display Port adapter pairing and resource management

To perform proper Display Port tunneling for Thunderbolt 3 devices we
need to allocate DP resources for DP IN port before they can be used.
The reason for this is that the user can also connect a monitor directly
to the Type-C ports in which case the Thunderbolt controller acts as
re-driver for Display Port (no tunneling takes place) taking the DP
sinks away from the connection manager. This allocation is done using
special sink allocation registers available through the link controller.

We can pair DP IN to DP OUT only if

* DP IN has sink allocated via link controller
* DP OUT port receives hotplug event

For DP IN adapters (only for the host router) we first query whether
there is DP resource available (it may be the previous instance of the
driver for example already allocated it) and if it is we add it to the
list. We then update the list when after each plug/unplug event to a DP
IN/OUT adapter. Each time the list is updated we try to find additional
DP IN <-> DP OUT pairs for tunnel establishment. This strategy also
makes it possible to establish another tunnel in case there are 3
monitors connected and one gets unplugged releasing the DP IN adapter
for the new tunnel.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add downstream PCIe port mappings for Alpine and Titan Ridge

In order to keep PCIe hierarchies consistent across hotplugs, add
hard-coded PCIe downstream port to Thunderbolt port for Alpine Ridge and
Titan Ridge as well.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Expand controller name in tb_switch_is_xy()

For a casual reader tb_switch_is_cr() does not tell much so instead
spell out the full controller name in the function name. For example
tb_switch_is_cr() becomes tb_switch_is_cactus_ridge() which is easier
to understand.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for lane bonding

Lane bonding allows aggregating two 10/20 Gb/s (depending on the
generation) lanes into a single 20/40 Gb/s bonded link. This allows
sharing the full bandwidth more efficiently. In order to establish lane
bonding we need to check that lane bonding is possible through link
controller and that both ends of the link actually supports 2x widths.
This also means that all the paths should be established through the
primary port so update tb_path_alloc() to handle this as well.

Lane bonding is supported starting from Falcon Ridge (2nd generation)
controllers.

We also expose the current speed and number of lanes under each device
except the host router following similar attribute naming than USB bus.
Expose speed and number of lanes for both directions to allow possibility
of asymmetric link in the future.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add helper macro to iterate over switch ports

There are quite many places in the driver where we iterate over each
port in the switch. To make it bit more convenient, add a macro that can
be used to iterate over each port and convert existing call sites to use it.

This is based on code by Lukas Wunner.

No functional changes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make tb_sw_write() take const parameter

The function does not modify the argument in any way so make it const.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Introduce tb_switch_is_icm()

We currently differentiate between SW CM (Software Connection Manager,
sometimes also called External Connection Manager) and ICM (Firmware
based Connection Manager, Internal Connection Manager) by looking
directly at the sw->config.enabled field which may be rather hard to
understand for the casual reader. For this reason introduce a wrapper
function with documentation that should make the intention more clear.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make sure device runtime resume completes before taking domain lock

When a device is authorized from userspace by writing to authorized
attribute we first take the domain lock and then runtime resume the
device in question. There are two issues with this.

First is that the device connected notifications are blocked during this
time which means we get them only after the authorization operation is
complete. Because of this the authorization needed flag from the
firmware notification is not reflecting the real authorization status
anymore. So what happens is that the "authorized" keeps returning 0 even
if the device was already authorized properly.

Second issue is that each time the controller is runtime resumed the
connection_id field of device connected notification may be different
than in the previous resume. We need to use the latest connection_id
otherwise the firmware rejects the authorization command.

Fix these by moving runtime resume operations to happen before the
domain lock is taken, and waiting for the updated device connected
notification from the firmware before we allow runtime resume of a
device to complete.

While there add missing locking to tb_switch_nvm_read().

Fixes: 09f11b6c99fe ("thunderbolt: Take domain lock in switch sysfs attribute callbacks")
Reported-by: Pengfei Xu <pengfei.xu@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make priority unsigned in struct tb_path

Clang warns:

drivers/thunderbolt/tunnel.c:504:17: warning: implicit truncation from
'int' to bit-field changes value from 5 to -3
[-Wbitfield-constant-conversion]
path->priority = 5;
^ ~
1 warning generated.

The priority member in struct tb_path is only ever assigned a positive
number:

$ rg -n priority drivers/thunderbolt/path.c
drivers/thunderbolt/tunnel.c:99: path->priority = 3;
drivers/thunderbolt/tunnel.c:308: path->priority = 2;
drivers/thunderbolt/tunnel.c:323: path->priority = 1;
drivers/thunderbolt/tunnel.c:504: path->priority = 5;

Furthermore, that value is only assigned to an unsigned integer in
tb_path_activate (the priority member in struct tb_regs_hop).

Fixes: 44242d6c9703 ("thunderbolt: Add support for DMA tunnels")
Link: https://github.com/ClangBuiltLinux/linux/issues/454
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Make __TB_[SW|PORT]_PRINT take const parameters

The printing macros do not modify the passed object so make them
const. While there make tb_route() to take const parameter as well.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for DMA tunnels

In addition to PCIe and Display Port tunnels it is also possible to
create tunnels that forward DMA traffic from the host interface adapter
(NHI) to a NULL port that is connected to another domain through a
Thunderbolt cable. These tunnels can be used to carry software messages
such as networking packets.

To support this we introduce another tunnel type (TB_TUNNEL_DMA) that
supports paths from NHI to NULL port and back.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Run tb_xdp_handle_request() in system workqueue

We run all XDomain requests during discovery in tb->wq and since it only
runs one work at the time it means that sending back reply to the other
domain may be delayed too much depending whether there is an active
XDomain discovery request running.

To make sure we can send reply to the other domain as soon as possible
run tb_xdp_handle_request() in system workqueue instead. Since the
device can be hot-removed in the middle we need to make sure the domain
structure is still around when the function is run so increase reference
count before we schedule the reply work.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for Display Port tunnels

Display Port tunnels are somewhat more complex than PCIe tunnels as it
requires 3 tunnels (AUX Rx/Tx and Video). In addition we are not
supposed to create the tunnels immediately when a DP OUT is enumerated.
Instead we need to wait until we get hotplug event to that adapter port
or check if the port has HPD set before tunnels can be established. This
adds Display Port tunneling support to the software connection manager.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Generalize port finding routines to support all port types

We will be needing these routines to find Display Port adapters as well
so modify them to take port type as the second parameter.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Scan only valid NULL adapter ports in hotplug

The only way to expand Thunderbolt topology is through the NULL adapter
ports (typically ports 1, 2, 3 and 4). There is no point handling
Thunderbolt hotplug events on any other port.

Add a helper function (tb_port_is_null()) that can be used to determine
if the port is NULL port, and use it in software connection manager code
when hotplug event is handled.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for full PCIe daisy chains

Currently the software connection manager (tb.c) has only supported
creating a single PCIe tunnel, no PCIe device daisy chaining has been
supported so far. This updates the software connection manager so that
it now can create PCIe tunnels for full chain of six devices.

Because PCIe allows DMA and opens possibility for DMA attacks we change
security level to "user" meaning that PCIe tunneling requires that the
userspace authorizes the devices first. This makes it possible to block
PCIe tunneling completely while still allowing other types of tunnels to
be automatically created.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Discover preboot PCIe paths the boot firmware established

In Apple Macs the boot firmware (EFI) connects all devices automatically
when the system is started, before it hands over to the OS. Instead of
ignoring we discover all those PCIe tunnels and record them using our
internal structures, just like we do when a device is connected after
the OS is already up.

By doing this we can properly tear down tunnels when devices are
disconnected. Also this allows us to resume the existing tunnels after
system suspend/resume cycle.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Extend tunnel creation to more than 2 adjacent switches

Now that we can allocate hop IDs per port on a path, we can take
advantage of this and create tunnels covering longer paths than just
between two adjacent switches. PCIe actually does not need this as it
is typically a daisy chain between two adjacent switches but this way we
do not need to hard-code creation of the tunnel.

While there add name to struct tb_path to make debugging easier, and
update kernel-doc comments.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add helper function to iterate from one port to another

We need to be able to walk from one port to another when we are creating
paths where there are multiple switches between two ports. For this
reason introduce a new function tb_next_port_on_path().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>

thunderbolt: Assign remote for both ports in case of dual link

Currently the driver only assigns remote port for the primary port if in
case of dual link. This makes things such as walking from one port to
another more complex than necessary because the code needs to change
from secondary to primary port if the path that is established is
created using secondary links.

In order to always assign both remote pointers we need to prevent the
scanning code from following the secondary link. Failing to do that
might cause problems as the same switch may be enumerated twice (or
removed in case of unplug). Handle that properly by introducing a new
function tb_port_has_remote() that returns true only for the primary
port. We also update tb_is_upstream_port() to support both dual link
ports, make it take const port pointer and move it below
tb_upstream_port() to keep similar functions close.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add functions for allocating and releasing HopIDs

Each port has a separate path configuration space that is used for
finding the next hop (switch) in the path. HopID is an index to this
configuration space. HopIDs 0 - 7 are reserved by the protocol.

In order to get next available HopID for each direction we provide two
pairs of helper functions that can be used to allocate and release
HopIDs for a given port.

While there remove obsolete TODO comment.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Generalize tunnel creation functionality

To be able to tunnel non-PCIe traffic, separate tunnel functionality
into generic and PCIe specific parts. Rename struct tb_pci_tunnel to
tb_tunnel, and make it hold an array of paths instead of just two.
Update all the tunneling functions to take this structure as parameter.

We also move tb_pci_port_active() to switch.c (and rename it) where we
will be keeping all port and switch related functions.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Cache adapter specific capability offset into struct port

The adapter specific capability either is there or not if the port does
not hold an adapter. Instead of always finding it on-demand we read the
offset just once when the port is initialized.

While there we update the struct port documentation to follow kernel-doc
format.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Set sleep bit when suspending switch

Thunderbolt 2 devices and beyond link controller needs to be notified
when a switch is going to be suspended by setting bit 31 in LC_SX_CTRL
register. Add this functionality to the software connection manager.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Configure lanes when switch is initialized

Thunderbolt 2 devices and beyond need to have additional bits set in
link controller specific registers. This includes two bits in LC_SX_CTRL
that tell the link controller which lane is connected and whether it is
upstream facing or not.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Move LC specific functionality into a separate file

We will be adding more link controller functionality in subsequent
patches and it does not make sense to keep all that in switch.c, so
separate LC functionality into its own file.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Enable TMU access when accessing port space on legacy devices

Light Ridge and Eagle Ridge both need to have TMU access enabled before
port space can be fully accessed so make sure it happens on those. This
allows us to get rid of the offset quirk in tb_port_find_cap().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Do not allocate switch if depth is greater than 6

Maximum depth in Thunderbolt topology is 6 so make sure it is not
possible to allocate switches that exceed the depth limit.

While at it update tb_switch_alloc() to use upper/lower_32_bits()
following tb_switch_alloc_safe_mode().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Take domain lock in switch sysfs attribute callbacks

switch_lock was introduced because it allowed serialization of device
authorization requests from userspace without need to take the big
domain lock (tb->lock). This was fine because device authorization with
ICM is just one command that is sent to the firmware. Now that we start
to handle all tunneling in the driver switch_lock is not enough because
we need to walk over the topology to establish paths.

For this reason drop switch_lock from the driver completely in favour of
big domain lock.

There is one complication, though. If userspace is waiting for the lock
in tb_switch_set_authorized(), it keeps the device_del() from removing
the sysfs attribute because it waits for active users to release the
attribute first which leads into following splat:

INFO: task kworker/u8:3:73 blocked for more than 61 seconds.
Tainted: G W 5.1.0-rc1+ #244
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u8:3 D12976 73 2 0x80000000
Workqueue: thunderbolt0 tb_handle_hotplug [thunderbolt]
Call Trace:
? __schedule+0x2e5/0x740
? _raw_spin_lock_irqsave+0x12/0x40
? prepare_to_wait_event+0xc5/0x160
schedule+0x2d/0x80
__kernfs_remove.part.17+0x183/0x1f0
? finish_wait+0x80/0x80
kernfs_remove_by_name_ns+0x4a/0x90
remove_files.isra.1+0x2b/0x60
sysfs_remove_group+0x38/0x80
sysfs_remove_groups+0x24/0x40
device_remove_attrs+0x3d/0x70
device_del+0x14c/0x360
device_unregister+0x15/0x50
tb_switch_remove+0x9e/0x1d0 [thunderbolt]
tb_handle_hotplug+0x119/0x5a0 [thunderbolt]
? process_one_work+0x1b7/0x420
process_one_work+0x1b7/0x420
worker_thread+0x37/0x380
? _raw_spin_unlock_irqrestore+0xf/0x30
? process_one_work+0x420/0x420
kthread+0x118/0x130
? kthread_create_on_node+0x60/0x60
ret_from_fork+0x35/0x40

We deal this by following what network stack did for some of their
attributes and use mutex_trylock() with restart_syscall(). This makes
userspace release the attribute allowing sysfs attribute removal to
progress before the write is restarted and eventually fail when the
attribute is removed.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Block reads and writes if switch is unplugged

If switch is already disconnected there is no point sending it commands
and waiting for timeout. Instead in that case return error immediately.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Drop duplicated get_switch_at_route()

tb_switch_find_by_route() does the same already so use it instead and
remove duplicated get_switch_at_route().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>

thunderbolt: Remove unused work field in struct tb_switch

This field is not used anywhere so remove it.

Reported-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add Intel as copyright holder

Intel has done pretty major changes to the driver and we continue to do
so in the future as well. Add Intel as copyright holder of the files we
have done changes.

While there drop "Cactus Ridge" from the headers because this driver
works also with other Thunderbolt controllers.

No functional changes intended.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <yehezkelshb@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Make the driver less verbose

Currently the driver logs quite a lot to the system message buffer even
when doing normal operations. This information is not useful for
ordinary users and might even annoy some.

For this reason convert most of the logs at info level to happen at
debug level instead. The nice output formatting is untouched.

Logging can be easily re-enabled by passing "thunderbolt.dyndbg" in the
kernel command line (or using the corresponding control file runtime).

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Yehezkel Bernat <yehezkelshb@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for runtime PM

When Thunderbolt host controller is set to RTD3 mode (Runtime D3) it is
present all the time. Because of this it is important to runtime suspend
the controller whenever possible. In case of ICM we have following rules
which all needs to be true before the host controller can be put to D3:

- The controller firmware reports to support RTD3
- All the connected devices announce support for RTD3
- There is no active XDomain connection

Implement this using standard Linux runtime PM APIs so that when all the
children devices are runtime suspended, the Thunderbolt host controller
PCI device is runtime suspended as well. The ICM firmware then starts
powering down power domains towards RTD3 but it can prevent this if it
detects that there is an active Display Port stream (this is not visible
to the software, though).

The Thunderbolt host controller will be runtime resumed either when
there is a remote wake event (device is connected or disconnected), or
when there is access from userspace that requires hardware access.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for preboot ACL

Preboot ACL is a mechanism that allows connecting Thunderbolt devices
boot time in more secure way than the legacy Thunderbolt boot support.
As with the legacy boot option, this also needs to be enabled from the
BIOS before booting is allowed. Difference to the legacy mode is that
the userspace software explicitly adds device UUIDs by sending a special
message to the ICM firmware. Only the devices listed in the boot ACL are
connected automatically during the boot. This works in both "user" and
"secure" security levels.

We implement this in Linux by exposing a new sysfs attribute (boot_acl)
below each Thunderbolt domain. The userspace software can then update
the full list as needed.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

thunderbolt: Add 'boot' attribute for devices

In various cases, Thunderbolt device can be connected by ICM on boot
without waiting for approval from user. Most cases are related to
OEM-specific BIOS configurations. This information is interesting for
user-space as if the device isn't in SW ACL, it may create a friction in
the user experience where the device is automatically authorized if it's
connected on boot but requires an explicit user action if connected
after OS is up. User-space can use this information to suggest adding
the device to SW ACL for auto-authorization on later connections.

Signed-off-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

thunderbolt: Add tb_switch_find_by_route()

With the new ICM messaging there is need for find switch by route string
instead of link and depth. Add new function that makes it possible.

Signed-off-by: Radion Mirchevsky <radion.mirchevsky@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

thunderbolt: Add tb_switch_get()

Sometimes there is need for increasing reference count of a switch as
well. This also follows what we have for xdomains.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for XDomain discovery protocol

When two hosts are connected over a Thunderbolt cable, there is a
protocol they can use to communicate capabilities supported by the host.
The discovery protocol uses automatically configured control channel
(ring 0) and is build on top of request/response transactions using
special XDomain primitives provided by the Thunderbolt base protocol.

The capabilities consists of a root directory block of basic properties
used for identification of the host, and then there can be zero or more
directories each describing a Thunderbolt service and its capabilities.

Once both sides have discovered what is supported the two hosts can
setup high-speed DMA paths and transfer data to the other side using
whatever protocol was agreed based on the properties. The software
protocol used to communicate which DMA paths to enable is service
specific.

This patch adds support for the XDomain discovery protocol to the
Thunderbolt bus. We model each remote host connection as a Linux XDomain
device. For each Thunderbolt service found supported on the XDomain
device, we create Linux Thunderbolt service device which Thunderbolt
service drivers can then bind to based on the protocol identification
information retrieved from the property directory describing the
service.

This code is based on the work done by Amir Levy and Michael Jamet.

Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

thunderbolt: Move tb_switch_phy_port_from_link() to thunderbolt.h

A Thunderbolt service might need to find the physical port from a link
the cable is connected to. For instance networking driver uses this
information to generate MAC address according the Apple ThunderboltIP
protocol.

Move this function to thunderbolt.h and rename it to
tb_phy_port_from_link() to reflect the fact that it does not take switch
as parameter.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

thunderbolt: Move thunderbolt domain structure to thunderbolt.h

These are needed by Thunderbolt services so move them to thunderbolt.h
to make sure they are available outside of drivers/thunderbolt.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

thunderbolt: use uuid_t instead of uuid_be

Switch thunderbolt to the new uuid type.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>

thunderbolt: Add support for host and device NVM firmware upgrade

Starting from Intel Falcon Ridge the NVM firmware can be upgraded by
using DMA configuration based mailbox commands. If we detect that the
host or device (device support starts from Intel Alpine Ridge) has the
DMA configuration based mailbox we expose NVM information to the
userspace as two separate Linux NVMem devices: nvm_active and
nvm_non_active. The former is read-only portion of the active NVM which
firmware upgrade tools can be use to find out suitable NVM image if the
device identification strings are not enough.

The latter is write-only portion where the new NVM image is to be
written by the userspace. It is up to the userspace to find out right
NVM image (the kernel does very minimal validation). The ICM firmware
itself authenticates the new NVM firmware and fails the operation if it
is not what is expected.

We also expose two new sysfs files per each switch: nvm_version and
nvm_authenticate which can be used to read the active NVM version and
start the upgrade process.

We also introduce safe mode which is the mode a switch goes when it does
not have properly authenticated firmware. In this mode the switch only
accepts a couple of commands including flashing a new NVM firmware image
and triggering power cycle.

This code is based on the work done by Amir Levy and Michael Jamet.

Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for Internal Connection Manager (ICM)

Starting from Intel Falcon Ridge the internal connection manager running
on the Thunderbolt host controller has been supporting 4 security
levels. One reason for this is to prevent DMA attacks and only allow
connecting devices the user trusts.

The internal connection manager (ICM) is the preferred way of connecting
Thunderbolt devices over software only implementation typically used on
Macs. The driver communicates with ICM using special Thunderbolt ring 0
(control channel) messages. In order to handle these messages we add
support for the ICM messages to the control channel.

The security levels are as follows:

none - No security, all tunnels are created automatically
user - User needs to approve the device before tunnels are created
secure - User need to approve the device before tunnels are created.
The device is sent a challenge on future connects to be able
to verify it is actually the approved device.
dponly - Only Display Port and USB tunnels can be created and those
are created automatically.

The security levels are typically configurable from the system BIOS and
by default it is set to "user" on many systems.

In this patch each Thunderbolt device will have either one or two new
sysfs attributes: authorized and key. The latter appears for devices
that support secure connect.

In order to identify the device the user can read identication
information, including UUID and name of the device from sysfs and based
on that make a decision to authorize the device. The device is
authorized by simply writing 1 to the "authorized" sysfs attribute. This
is following the USB bus device authorization mechanism. The secure
connect requires an additional challenge step (writing 2 to the
"authorized" attribute) in future connects when the key has already been
stored to the NVM of the device.

Non-ICM systems (before Alpine Ridge) continue to use the existing
functionality and the security level is set to none. For systems with
Alpine Ridge, even on Apple hardware, we will use ICM.

This code is based on the work done by Amir Levy and Michael Jamet.

Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for DMA configuration based mailbox

The DMA (NHI) port of a switch provides access to the NVM of the host
controller (and devices starting from Intel Alpine Ridge). The NVM
contains also more complete DROM for the root switch including vendor
and device identification strings.

This will look for the DMA port capability for each switch and if found
populates sw->dma_port. We then teach tb_drom_read() to read the DROM
information from NVM if available for the root switch.

The DMA port capability also supports upgrading the NVM for both host
controller and devices which will be added in subsequent patches.

This code is based on the work done by Amir Levy and Michael Jamet.

Signed-off-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Store Thunderbolt generation in the switch structure

In some cases it is useful to know what is the Thunderbolt generation
the switch supports. This introduces a new field to struct switch that
stores the generation of the switch based on the device ID. Unknown
switches (there should be none) are assumed to be first generation to be
on the safe side.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Rework control channel to be more reliable

If a request times out the response might arrive right after the request
is failed. This response is pushed to the kfifo and next request will
read it instead. Since it most likely will not pass our validation
checks in parse_header() the next request will fail as well, and
response to that request will be pushed to the kfifo, ad infinitum.

We end up in a situation where all requests fail and no devices can be
added anymore until the driver is unloaded and reloaded again.

To overcome this, rework the control channel so that we will have a
queue of outstanding requests. Each request will be handled in turn and
the response is validated against what is expected. Unexpected packets
(for example responses for requests that have been timed out) are
dropped. This model is copied from Greybus implementation with small
changes here and there to get it cope with Thunderbolt control packets.

In addition the configuration packets support sequence number which the
switch is supposed to copy from the request to response. We use this to
drop responses that are already timed out. Taking advantage of the
sequence number, we automatically retry configuration read/write 4 times
before giving up.

Also timeout is not a programming error so there is no need to trigger a
scary backtrace (WARN), instead we just log a warning. After all
Thunderbolt devices are hot-pluggable by definition which means user can
unplug a device any time and that is totally acceptable.

With this change there is no need to take the global domain lock when
sending configuration packets anymore. This is useful when we add
support for cross-domain (XDomain) communication later on.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Let the connection manager handle all notifications

Currently the control channel (ctl.c) handles the one supported
notification (PLUG_EVENT) and sends back ACK accordingly. However, we
are going to add support for the internal connection manager (ICM) that
needs to handle a different notifications. So instead of dealing
everything in the control channel, we change the callback to take an
arbitrary thunderbolt packet and convert the native connection manager
to handle the event itself.

In addition we only push replies we know of to the response FIFO.
Everything else is treated as notification (or request) and is expected
to be dealt by the connection manager implementation.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Read vendor and device name from DROM

The device DROM contains name of the vendor and device among other
things. Extract this information and expose it to the userspace via two
new attributes.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Convert switch to a device

Thunderbolt domain consists of switches that are connected to each
other, forming a bus. This will convert each switch into a real Linux
device structure and adds them to the domain. The advantage here is
that we get all the goodies from the driver core, like reference
counting and sysfs hierarchy for free.

Also expose device identification information to the userspace via new
sysfs attributes.

In order to support internal connection manager (ICM) we separate switch
configuration into its own function (tb_switch_configure()) which is
only called by the existing native connection manager implementation
used on Macs.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Introduce thunderbolt bus and connection manager

Thunderbolt fabric consists of one or more switches. This fabric is
called domain and it is controlled by an entity called connection
manager. The connection manager can be either internal (driven by a
firmware running on the host controller) or external (software driver).
This driver currently implements support for the latter.

In order to manage switches and their properties more easily we model
this domain structure as a Linux bus. Each host controller adds a domain
device to this bus, and these devices are named as domainN where N
stands for index or id of the current domain.

We then abstract connection manager specific operations into a new
structure tb_cm_ops and convert the existing tb.c to fill those
accordingly. This makes it easier to add support for the internal
connection manager in subsequent patches.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Rework capability handling

Organization of the capabilities in switches and ports is not so random
after all. Rework the capability handling functionality so that it
follows how capabilities are organized and provide two new functions
(tb_switch_find_vse_cap() and tb_port_find_cap()) which can be used to
extract capabilities for ports and switches. Then convert the current
users over these.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Use const buffer pointer in write operations

These functions should not (and do not) modify the argument in any way
so make it const.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Reviewed-by: Michael Jamet <michael.jamet@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Fix typos and magic number

Fix typo in tb_cfg_print_error() message. Fix bytecount in struct
tb_drom_entry_port comment. Replace magic number in tb_switch_alloc().
Rename tb_sw_set_unpplugged() and TB_CAL_IECS to fix typos.

[bhelgaas: no functional change intended]
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Andreas Noever <andreas.noever@gmail.com>

thunderbolt: Fix header declaration of tb_find_cap

tb_find_cap in cap.c takes an enum tb_cap and not an u32. Fix the
declaration in tb.h.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Read port configuration from eeprom.

All Thunderbolt switches (except the root switch) contain a drom which
contains information about the device. Right now we only read the UID.

Add code to read and parse this drom. For now we are only interested in
which ports are disabled and which ports are "dual link ports" (a
physical thunderbolt port/socket contains two such ports).

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add suspend/hibernate support

We use _noirq since we have to restore the pci tunnels before the pci
core wakes the tunneled devices.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Read switch uid from EEPROM

Add eeprom access code and read the uid during switch initialization.
The UID will be used to check device identity after suspend.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add support for simple pci tunnels

A pci downstream and pci upstream port can be connected through a
tunnel. To establish the tunnel we have to setup two unidirectional
paths between the two ports.

Right now we only support paths with two hops (i.e. no chaining) and at
most one pci device per thunderbolt device.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add path setup code.

A thunderbolt path is a unidirectional channel between two thunderbolt
ports. Two such paths are needed to establish a pci tunnel.

This patch introduces struct tb_path as well as a set of tb_path_*
methods which are used to activate & deactivate paths.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Handle hotplug events

We receive a plug event callback whenever a thunderbolt device is added
or removed. This patch fills in the tb_handle_hotplug method and starts
reacting to these events by adding/removing switches from the hierarchy.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Scan for downstream switches

Add utility methods tb_port_state and tb_wait_for_port. Add
tb_scan_switch which recursively checks for downstream switches.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Enable plug events

Thunderbolt switches have a plug events capability. This patch adds the
tb_plug_events_active method and uses it to activate plug events during
switch allocation.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Add thunderbolt capability handling

Thunderbolt config areas contain capability lists similar to those found
on pci devices. This patch introduces a tb_find_cap utility method to
search for capabilities.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Initialize root switch and ports

This patch adds the structures tb_switch and tb_port as well as code to
initialize the root switch.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

thunderbolt: Setup control channel

Add struct tb which will contain our view of the thunderbolt bus. For
now it just contains a pointer to the control channel and a workqueue
for hotplug events.

Add thunderbolt_alloc_and_start() and thunderbolt_shutdown_and_free()
which are responsible for setup and teardown of struct tb.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>