firmware: coreboot: framebuffer: Allow building with simpledrm

The coreboot framebuffer driver registers a "simple-framebuffer" device
based on the information from the firmware, after checking that it's
compatible with the formats listed in simplefb.h. It was added before
simpledrm, and its Kconfig marked as dependent on the simplefb driver.

The simpledrm driver can also handle "simple-framebuffer" devices and
the coreboot framebuffer works fine with it on a 'Lick' Chromebook.
Allow building the coreboot framebuffer driver with simpledrm as well.

Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Link: https://lore.kernel.org/r/20230725174334.887485-1-alpernebiyasak@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: coreboot: Remove GOOGLE_COREBOOT_TABLE_ACPI/OF Kconfig entries

Ever since commit a28aad66da8b ("firmware: coreboot: Collapse platform
drivers into bus core") the Kconfig entries GOOGLE_COREBOOT_TABLE_OF
and GOOGLE_COREBOOT_TABLE_ACPI have been dead. They have no "help"
text and thus aren't user choosable. They also aren't "select"ed by
anything. They also control the compilation of no code.

Let's remove them.

Fixes: a28aad66da8b ("firmware: coreboot: Collapse platform drivers into bus core")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Acked-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20230207081130.1.I657776750156793721efa247ce6293445137bc8a@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: google: Implement cbmem in sysfs driver

The CBMEM area is a downward-growing memory region used by coreboot to
dynamically allocate tagged data structures ("CBMEM entries") that
remain resident during boot.

This implements a driver which exports access to the CBMEM entries
via sysfs under /sys/bus/coreboot/devices/cbmem-<id>.

This implementation is quite versatile. Examples of how it could be
used are given below:

* Tools like util/cbmem from the coreboot tree could use this driver
instead of finding CBMEM in /dev/mem directly. Alternatively,
firmware developers debugging an issue may find the sysfs interface
more ergonomic than the cbmem tool and choose to use it directly.

* The crossystem tool, which exposes verified boot variables, can use
this driver to read the vboot work buffer.

* Tools which read the BIOS SPI flash (e.g., flashrom) can find the
flash layout in CBMEM directly, which is significantly faster than
searching the flash directly.

Write access is provided to all CBMEM regions via
/sys/bus/coreboot/devices/cbmem-<id>/mem, as the existing cbmem
tooling updates this memory region, and envisioned use cases with
crossystem can benefit from updating memory regions.

Link: https://issuetracker.google.com/239604743
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Tested-by: Jack Rosenthal <jrosenth@chromium.org>
Signed-off-by: Jack Rosenthal <jrosenth@chromium.org>
Link: https://lore.kernel.org/r/20221104161528.531248-1-jrosenth@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: google: Properly state IOMEM dependency

The Google Coreboot implementation requires IOMEM functions
(memmremap, memunmap, devm_memremap), but does not specify this is its
Kconfig. This results in build errors when HAS_IOMEM is not set, such as
on some UML configurations:

/usr/bin/ld: drivers/firmware/google/coreboot_table.o: in function `coreboot_table_probe':
coreboot_table.c:(.text+0x311): undefined reference to `memremap'
/usr/bin/ld: coreboot_table.c:(.text+0x34e): undefined reference to `memunmap'
/usr/bin/ld: drivers/firmware/google/memconsole-coreboot.o: in function `memconsole_probe':
memconsole-coreboot.c:(.text+0x12d): undefined reference to `memremap'
/usr/bin/ld: memconsole-coreboot.c:(.text+0x17e): undefined reference to `devm_memremap'
/usr/bin/ld: memconsole-coreboot.c:(.text+0x191): undefined reference to `memunmap'
/usr/bin/ld: drivers/firmware/google/vpd.o: in function `vpd_section_destroy.isra.0':
vpd.c:(.text+0x300): undefined reference to `memunmap'
/usr/bin/ld: drivers/firmware/google/vpd.o: in function `vpd_section_init':
vpd.c:(.text+0x382): undefined reference to `memremap'
/usr/bin/ld: vpd.c:(.text+0x459): undefined reference to `memunmap'
/usr/bin/ld: drivers/firmware/google/vpd.o: in function `vpd_probe':
vpd.c:(.text+0x59d): undefined reference to `memremap'
/usr/bin/ld: vpd.c:(.text+0x5d3): undefined reference to `memunmap'
collect2: error: ld returned 1 exit status

Fixes: a28aad66da8b ("firmware: coreboot: Collapse platform drivers into bus core")
Acked-By: anton ivanov <anton.ivanov@cambridgegreys.com>
Acked-By: Julius Werner <jwerner@chromium.org>
Signed-off-by: David Gow <davidgow@google.com>
Link: https://lore.kernel.org/r/20220225041502.1901806-1-davidgow@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: Update Kconfig help text for Google firmware

The help text for GOOGLE_FIRMWARE states that it should only be
enabled when building a kernel for Google's own servers. However,
many of the drivers dependent on it are also useful on Chromebooks or
on any platform using coreboot.

Update the help text to reflect this double duty.

Fixes: d384d6f43d1e ("firmware: google memconsole: Add coreboot support")
Reviewed-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Link: https://lore.kernel.org/r/20180618225540.GD14131@decadent.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

efi: gsmi: fix false dependency on CONFIG_EFI_VARS

The gsmi code does not actually rely on CONFIG_EFI_VARS, since it only
uses the efivars abstraction that is included unconditionally when
CONFIG_EFI is defined. CONFIG_EFI_VARS controls the inclusion of the
code that exposes the sysfs entries, and which has been deprecated for
some time.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gsmi: Remove autoselected dependency on EFI and EFI_VARS

Instead of selecting EFI and EFI_VARS automatically when GSMI is
enabled let that portion of the driver be conditionally compiled
if EFI and EFI_VARS are enabled.

This allows the rest of the driver (specifically event log) to
be used if EFI_VARS is not enabled.

To test:
1) verify that EFI_VARS is not automatically selected when
CONFIG_GOOGLE_GSMI is enabled
2) verify that the kernel boots on Link and that GSMI event log
is still available and functional
3) specifically boot the kernel on Alex to ensure it does not
try to load efivars and that gsmi also does not load because it
is not in the supported DMI table

Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Filipe Brandenburger <filbranden@chromium.org>
Signed-off-by: Furquan Shaikh <furquan@google.com>
Tested-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
[zwisler: update changelog for upstream]
Signed-off-by: Ross Zwisler <zwisler@google.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: coreboot: Collapse platform drivers into bus core

The DT based and ACPI based platform drivers here do the same thing; map
some memory and hand it over to the coreboot bus to populate devices.
The only major difference is that the DT based driver doesn't map the
coreboot table header to figure out how large of a region to map for the
whole coreboot table and it uses of_iomap() instead of ioremap_cache().
A cached or non-cached mapping shouldn't matter here and mapping some
smaller region first before mapping the whole table is just more work
but should be OK. In the end, we can remove two files and combine the
code all in one place making it easier to reason about things.

We leave the old Kconfigs in place for a little while longer but make
them hidden and select the previously hidden config option. This way
users can upgrade without having to know to reselect this config in the
future. Later on we can remove the old hidden configs.

Cc: Wei-Ning Huang <wnhuang@chromium.org>
Cc: Julius Werner <jwerner@chromium.org>
Cc: Brian Norris <briannorris@chromium.org>
Cc: Samuel Holland <samuel@sholland.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: coreboot: Add coreboot framebuffer driver

Register a simplefb framebuffer when the coreboot table contains a
framebuffer entry.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: Google VPD sysfs driver

This patch introduces the Google Vital Product Data driver.

This driver reads Vital Product Data from coreboot tables and then
creates the corresponding sysfs entries under /sys/firmware/vpd to
provide easy access for userspace programs (does not require flashrom).

The sysfs is structured as follow:

/sys/firmware/vpd
|-- ro
| |-- key1
| `-- key2
|-- ro_raw
|-- rw
| `-- key1
`-- rw_raw

Where ro_raw and rw_raw contain the raw VPD partition. The files under
ro and rw correspond to the key name in the VPD and the the file content
is the value for the key.

Signed-off-by: Wei-Ning Huang <wnhuang@google.com>
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: google memconsole: Add ARM/ARM64 support

This patch expands the Google firmware memory console driver to also
work on certain tree based platforms running coreboot, such as ARM/ARM64
Chromebooks. This patch now adds another path to find the coreboot table
through the device tree. In order to find that, a second level
bootloader must have installed the 'coreboot' compatible device tree
node that describes its base address and size.

This patch is a rework/split/merge of patches from the chromeos v4.4
kernel tree originally authored by:
Wei-Ning Huang <wnhuang@chromium.org>
Julius Werner <jwerner@chromium.org>
Brian Norris <briannorris@chromium.org>

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: google memconsole: Add coreboot support

Coreboot (http://www.coreboot.org) allows to save the firmware console
output in a memory buffer. With this patch, the address of this memory
buffer is obtained from coreboot tables on x86 chromebook devices
declaring an ACPI device with name matching GOOGCB00 or BOOT0000.

If the memconsole-coreboot driver is able to find the coreboot table,
the memconsole driver sets the cbmem_console address and initializes the
memconsole sysfs entries.

The coreboot_table-acpi driver is responsible for setting the address of
the coreboot table header when probed. If this address is not yet set
when memconsole-coreboot is probed, then the probe is deferred by
returning -EPROBE_DEFER.

This patch is a rework/split/merge of patches from the chromeos v4.4
kernel tree originally authored by:
Vadim Bendebury <vbendeb@chromium.org>
Wei-Ning Huang <wnhuang@google.com>
Yuji Sasaki <sasakiy@google.com>
Duncan Laurie <dlaurie@chromium.org>
Julius Werner <jwerner@chromium.org>
Brian Norris <briannorris@chromium.org>

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: google memconsole: Move specific EBDA parts

This patch splits memconsole.c in 2 parts. One containing the
architecture-independent part and the other one containing the EBDA
specific part. This prepares the integration of coreboot support for the
memconsole.

The memconsole driver is now named as memconsole-x86-legacy.

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: google memconsole: Remove useless submenu in Kconfig

This patch removes the "Google Firmware Drivers" menu containing a
menuconfig entry with the exact same name. The menuconfig is now
directly under the "Firmware Drivers" entry.

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware/google: drop 'select EFI' to avoid recursive dependency

The GOOGLE_SMI Kconfig symbol depends on DMI and selects EFI. This
causes problems on other archs when introducing DMI support that depends
on EFI, as it results in a recursive dependency:

arch/arm/Kconfig:1845:error: recursive dependency detected!
arch/arm/Kconfig:1845: symbol DMI depends on EFI

Fix by changing the 'select EFI' to a 'depends on EFI'.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: David Rientjes <rientjes@google.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

firmware: fix GOOGLE_SMI kconfig dependency warning

Is it meaningful/useful to enable EFI_VARS but not EFI?
That's what GOOGLE_SMI does. Make it enable EFI also.

Fixes this kconfig dependency warning:

warning: (GOOGLE_SMI) selects EFI_VARS which has unmet direct dependencies (EFI)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Introduce CONFIG_GOOGLE_FIRMWARE

In order to keep Google's firmware drivers organized amongst themselves,
all Google firmware drivers are gated on CONFIG_GOOGLE_FIRMWARE=y, which
defaults to 'n' in the kernel build.

Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

driver: Google Memory Console

This patch introduces the 'memconsole' driver.

Our firmware gives us access to an in-memory log of the firmware's
output. This gives us visibility in a data-center of headless machines
as to what the firmware is doing.

The memory console is found by the driver by finding a header block in
the EBDA. The buffer is then copied out, and is exported to userland in
the file /sys/firmware/log.

Signed-off-by: San Mehat <san@google.com>
Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

driver: Google EFI SMI

The "gsmi" driver bridges userland with firmware specific routines for
accessing hardware.

Currently, this driver only supports NVRAM and eventlog information.
Deprecated functions have been removed from the driver, though their
op-codes are left in place so that they are not re-used.

This driver works by trampolining into the firmware via the smi_command
outlined in the FADT table. Three protocols are used due to various
limitations over time, but all are included herein.

This driver should only ever load on Google boards, identified by either
a "Google, Inc." board vendor string in DMI, or "GOOGLE" in the OEM
strings of the FADT ACPI table. This logic happens in
gsmi_system_valid().

Signed-off-by: Duncan Laurie <dlaurie@google.com>
Signed-off-by: Aaron Durbin <adurbin@google.com>
Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>