powerpc: Add missing headers

Don't inherit headers "by chances" from asm/prom.h, asm/mpc52xx.h,
asm/pci.h etc...

Include the needed headers, and remove asm/prom.h when it was
needed exclusively for pulling necessary headers.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/be8bdc934d152a7d8ee8d1a840d5596e2f7d85e0.1646767214.git.christophe.leroy@csgroup.eu

powerpc/powernv/pci: Rework pnv_opal_pci_msi_eoi()

pnv_opal_pci_msi_eoi() is called from KVM to EOI passthrough interrupts
when in real mode. Adding MSI domain broke the hack using the
'ioda.irq_chip' field to deduce the owning PHB. Fix that by using the
IRQ chip data in the MSI domain.

The 'ioda.irq_chip' field is now unused and could be removed from the
pnv_phb struct.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701132750.1475580-30-clg@kaod.org

powerpc/powernv/ioda: Find opencapi slot for a device node

Unlike real PCI slots, opencapi slots are directly associated to
the (virtual) opencapi PHB, there's no intermediate bridge. So when
looking for a slot ID, we must start the search from the device node
itself and not its parent.

Also, the slot ID is not attached to a specific bdfn, so let's build
it from the PHB ID, like skiboot.

Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-6-fbarrat@linux.ibm.com

powerpc/powernv: remove the unused tunneling exports

These have been unused anywhere in the kernel tree ever since they've
been added to the kernel.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: remove the unused pnv_pci_set_p2p function

This function has never been used anywhere in the kernel tree since it
was added to the tree. We also now have proper PCIe P2P APIs in the core
kernel, and any new P2P support should be using those.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

PCI: hotplug: Drop hotplug_slot_info

Ever since the PCI hotplug core was introduced in 2002, drivers had to
allocate and register a struct hotplug_slot_info for every slot:
https://git.kernel.org/tglx/history/c/a8a2069f432c

Apparently the idea was that drivers furnish the hotplug core with an
up-to-date card presence status, power status, latch status and
attention indicator status as well as notify the hotplug core of changes
thereof. However only 4 out of 12 hotplug drivers bother to notify the
hotplug core with pci_hp_change_slot_info() and the hotplug core never
made any use of the information: There is just a single macro in
pci_hotplug_core.c, GET_STATUS(), which uses the hotplug_slot_info if
the driver lacks the corresponding callback in hotplug_slot_ops. The
macro is called when the user reads the attribute via sysfs.

Now, if the callback isn't defined, the attribute isn't exposed in sysfs
in the first place (see e.g. has_power_file()). There are only two
situations when the hotplug_slot_info would actually be accessed:

* If the driver defines ->enable_slot or ->disable_slot but not
->get_power_status.

* If the driver defines ->set_attention_status but not
->get_attention_status.

There is no driver doing the former and just a single driver doing the
latter, namely pnv_php.c. Amend it with a ->get_attention_status
callback. With that, the hotplug_slot_info becomes completely unused by
the PCI hotplug core. But a few drivers use it internally as a cache:

cpcihp uses it to cache the latch_status and adapter_status.
cpqhp uses it to cache the adapter_status.
pnv_php and rpaphp use it to cache the attention_status.
shpchp uses it to cache all four values.

Amend these drivers to cache the information in their private slot
struct. shpchp's slot struct already contains members to cache the
power_status and adapter_status, so additional members are only needed
for the other two values. In the case of cpqphp, the cached value is
only accessed in a single place, so instead of caching it, read the
current value from the hardware.

Caution: acpiphp, cpci, cpqhp, shpchp, asus-wmi and eeepc-laptop
populate the hotplug_slot_info with initial values on probe. That code
is herewith removed. There is a theoretical chance that the code has
side effects without which the driver fails to function, e.g. if the
ACPI method to read the adapter status needs to be executed at least
once on probe. That seems unlikely to me, still maintainers should
review the changes carefully for this possibility.

Rafael adds: "I'm not aware of any case in which it will break anything,
[...] but if that happens, it may be necessary to add the execution of
the control methods in question directly to the initialization part."

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> # drivers/pci/hotplug/rpa*
Acked-by: Sebastian Ott <sebott@linux.ibm.com> # drivers/pci/hotplug/s390*
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86
Cc: Len Brown <lenb@kernel.org>
Cc: Scott Murray <scott@spiteful.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Oliver OHalloran <oliveroh@au1.ibm.com>
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>

Revert "powerpc/powernv: Add support for the cxl kernel api on the real phb"

Remove abandonned capi support for the Mellanox CX4.

This reverts commit 4361b03430d685610e5feea3ec7846e8b9ae795f.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Enable tunneled operations

P9 supports PCI tunneled operations (atomics and as_notify). This
patch adds support for tunneled operations on powernv, with a new
API, to be called by device drivers:

pnv_pci_enable_tunnel()
Enable tunnel operations, tell driver the 16-bit ASN indication
used by kernel.

pnv_pci_disable_tunnel()
Disable tunnel operations.

pnv_pci_set_tunnel_bar()
Tell kernel the Tunnel BAR Response address used by driver.
This function uses two new OPAL calls, as the PBCQ Tunnel BAR
register is configured by skiboot.

pnv_pci_get_as_notify_info()
Return the ASN info of the thread to be woken up.

Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Enable PCI peer-to-peer

P9 has support for PCI peer-to-peer, enabling a device to write in the
MMIO space of another device directly, without interrupting the CPU.

This patch adds support for it on powernv, by adding a new API to be
called by drivers. The pnv_pci_set_p2p(...) call configures an
'initiator', i.e the device which will issue the MMIO operation, and a
'target', i.e. the device on the receiving side.

P9 really only supports MMIO stores for the time being but that's
expected to change in the future, so the API allows to define both
load and store operations.

/* PCI p2p descriptor */
#define OPAL_PCI_P2P_ENABLE 0x1
#define OPAL_PCI_P2P_LOAD 0x2
#define OPAL_PCI_P2P_STORE 0x4

int pnv_pci_set_p2p(struct pci_dev *initiator, struct pci_dev *target,
u64 desc)

It uses a new OPAL call, as the configuration magic is done on the
PHBs by skiboot.

Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
[mpe: Drop unrelated OPAL calls, s/uint64_t/u64/, minor formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

drivers/pci/hotplug: Mask PDC interrupt if required

We're supporting surprise hotplug on PCI slots behind root port
or PCIe switch downstream ports, which don't claim the capability
in hardware register (offset: PCIe cap + PCI_EXP_SLTCAP). PEX8718
is one of the examples. For those PCI slots, the PDC (Presence
Detection Change) event isn't reliable and the underly (skiboot)
firmware has best judgement.

This masks the PDC event when skiboot requests by "ibm,slot-broken-pdc"
property in PCI slot's device-tree node.

Reported-by: Hank Chang <hankmax0000@gmail.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Tested-by: Willie Liauw <williel@supermicro.com.tw>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Specify proper data type for PCI_SLOT_ID_PREFIX

This fixes the warning reported from sparse:

eeh-powernv.c:875:23: warning: constant 0x8000000000000000 is so big it is unsigned long

Fixes: ebe225312739 ("powerpc/powernv: Support PCI slot ID")
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

drivers/pci/hotplug: Support surprise hotplug in powernv driver

This supports PCI surprise hotplug. The design is highlighted as
below:

* The PCI slot's surprise hotplug capability is exposed through
device node property "ibm,slot-surprise-pluggable", meaning
PCI surprise hotplug will be disabled if skiboot doesn't support
it yet.
* The interrupt because of presence or link state change is raised
on surprise hotplug event. One event is allocated and queued to
the PCI slot for workqueue to pick it up and process in serialized
fashion. The code flow for surprise hotplug is same to that for
managed hotplug except: the affected PEs are put into frozen state
to avoid unexpected EEH error reporting in surprise hot remove path.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Provide facilities for EOI, usable from real mode

This adds a new function pnv_opal_pci_msi_eoi() which does the part of
end-of-interrupt (EOI) handling of an MSI which involves doing an
OPAL call. This function can be called in real mode. This doesn't
just export pnv_ioda2_msi_eoi() because that does a call to
icp_native_eoi(), which does not work in real mode.

This also adds a function, is_pnv_opal_msi(), which KVM can call to
check whether an interrupt is one for which we should be calling
pnv_opal_pci_msi_eoi() when we need to do an EOI.

[paulus@ozlabs.org - split out the addition of pnv_opal_pci_msi_eoi()
from Suresh's patch "KVM: PPC: Book3S HV: Handle passthrough
interrupts in guest"; added is_pnv_opal_msi(); wrote description.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

PCI/hotplug: pnv_php: export symbols and move struct types needed by cxl

The cxl driver will use infrastructure from pnv_php to handle device tree
updates when switching bi-modal CAPI cards into CAPI mode.

To enable this, export pnv_php_find_slot() and
pnv_php_set_slot_power_state(), and add corresponding declarations, as well
as the definition of struct pnv_php_slot, to asm/pnv-pci.h.

Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: linux-pci@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Add support for the cxl kernel api on the real phb

This adds support for the peer model of the cxl kernel api to the
PowerNV PHB, in which physical function 0 represents the cxl function on
the card (an XSL in the case of the CX4), which other physical functions
will use for memory access and interrupt services. It is referred to as
the peer model as these functions are peers of one another, as opposed
to the Virtual PHB model which forms a hierarchy.

This patch exports APIs to enable the peer mode, check if a PCI device
is attached to a PHB in this mode, and to set and get the peer AFU for
this mode.

The cxl driver will enable this mode for supported cards by calling
pnv_cxl_enable_phb_kernel_api(). This will set a flag in the PHB to note
that this mode is enabled, and switch out it's controller_ops for the
cxl version.

The cxl version of the controller_ops struct implements it's own
versions of the enable_device_hook and release_device to handle
refcounting on the peer AFU and to allocate a default context for the
device.

Once enabled, the cxl kernel API may not be disabled on a PHB. Currently
there is no safe way to disable cxl mode short of a reboot, so until
that changes there is no reason to support the disable path.

Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Functions to get/set PCI slot state

This exports 4 functions, which base on the corresponding OPAL
APIs to get/set PCI slot status. Those functions are going to
be used by PowerNV PCI hotplug driver:

pnv_pci_get_device_tree() opal_get_device_tree()
pnv_pci_get_presence_state() opal_pci_get_presence_state()
pnv_pci_get_power_state() opal_pci_get_power_state()
pnv_pci_set_power_state() opal_pci_set_power_state()

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Introduce pnv_pci_get_slot_id()

This introduces pnv_pci_get_slot_id() to get the hotpluggable PCI
slot ID from the corresponding device node. It will be used by
hotplug driver.

Requested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powernv: Support PCI slot ID

The reset and poll functionality from (OPAL) firmware supports
PHB and PCI slot at same time. They are identified by ID. This
supports PCI slot ID by:

* Rename the argument name for opal_pci_reset() and opal_pci_poll()
accordingly
* Rename pnv_eeh_phb_poll() to pnv_eeh_poll() and adjust its argument
name.
* One macro is added to produce PCI slot ID.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

cxl: Move include file cxl.h -> cxl-base.h

This moves the current include file from cxl.h -> cxl-base.h. This current
include file is used only to pass information between the base driver that
needs to be built into the kernel and the cxl module.

This is to make way for a new include/misc/cxl.h which will
contain just the kernel API for other driver to use

Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

cxl: Fix device_node reference counting

When unbinding and rebinding the driver on a system with a card in PHB0, this
error condition is reached after a few attempts:

ERROR: Bad of_node_put() on /pciex@3fffe40000000
CPU: 0 PID: 3040 Comm: bash Not tainted 3.18.0-rc3-12545-g3627ffe #152
Call Trace:
[c000000721acb5c0] [c00000000086ef94] .dump_stack+0x84/0xb0 (unreliable)
[c000000721acb640] [c00000000073a0a8] .of_node_release+0xd8/0xe0
[c000000721acb6d0] [c00000000044bc44] .kobject_release+0x74/0xe0
[c000000721acb760] [c0000000007394fc] .of_node_put+0x1c/0x30
[c000000721acb7d0] [c000000000545cd8] .cxl_probe+0x1a98/0x1d50
[c000000721acb900] [c0000000004845a0] .local_pci_probe+0x40/0xc0
[c000000721acb980] [c000000000484998] .pci_device_probe+0x128/0x170
[c000000721acba30] [c00000000052400c] .driver_probe_device+0xac/0x2a0
[c000000721acbad0] [c000000000522468] .bind_store+0x108/0x160
[c000000721acbb70] [c000000000521448] .drv_attr_store+0x38/0x60
[c000000721acbbe0] [c000000000293840] .sysfs_kf_write+0x60/0xa0
[c000000721acbc50] [c000000000292500] .kernfs_fop_write+0x140/0x1d0
[c000000721acbcf0] [c000000000208648] .vfs_write+0xd8/0x260
[c000000721acbd90] [c000000000208b18] .SyS_write+0x58/0x100
[c000000721acbe30] [c000000000009258] syscall_exit+0x0/0x98

We are missing a call to of_node_get(). pnv_pci_to_phb_node() should
call of_node_get() otherwise np's reference count isn't incremented and
it might go away. Rename pnv_pci_to_phb_node() to pnv_pci_get_phb_node()
so it's clear it calls of_node_get().

Signed-off-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

cxl: Enable CAPP recovery

Turning snoops on is the last step in CAPP recovery. Sapphire is expected to
have reinitialized the PHB and done the previous recovery steps.

Add mode argument to opal call to do this. Driver can turn snoops off although
it does not currently.

Signed-off-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/powerpc: Add new PCIe functions for allocating cxl interrupts

This adds a number of functions for allocating IRQs under powernv PCIe for cxl.

Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>