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: 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>

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>

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>

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>