pstore/ram: Introduce max_reason and convert dump_oops

Now that pstore_register() can correctly pass max_reason to the kmesg
dump facility, introduce a new "max_reason" module parameter and
"max-reason" Device Tree field.

The "dump_oops" module parameter and "dump-oops" Device
Tree field are now considered deprecated, but are now automatically
converted to their corresponding max_reason values when present, though
the new max_reason setting has precedence.

For struct ramoops_platform_data, the "dump_oops" member is entirely
replaced by a new "max_reason" member, with the only existing user
updated in place.

Additionally remove the "reason" filter logic from ramoops_pstore_write(),
as that is not specifically needed anymore, though technically
this is a change in behavior for any ramoops users also setting the
printk.always_kmsg_dump boot param, which will cause ramoops to behave as
if max_reason was set to KMSG_DUMP_MAX.

Co-developed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Link: https://lore.kernel.org/lkml/20200515184434.8470-6-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>

platform/chrome: chromeos_pstore: set user space log size

On x86 ChromiumOS devices, the pmsg_size is set to 0 (check
/sys/module/ramoops/parameters/pmsg_size): this prevents use of
pstore-pmsg, even if CONFIG_PSTORE_PMSG is enabled. Set pmsg_size
to a value that is consistent with the size used on non-x86 ChromiumOS
devices.

Signed-off-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

platform/chrome: cromeos_pstore: switch to SPDX identifier

Adopt the SPDX license identifier headers to ease license compliance
management. Also fix the module license mismatch and change the term
'Chrome OS' for 'ChromeOS' to be coherent with other drivers.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>

dmi: Mark all struct dmi_system_id instances const

... and __initconst if applicable.

Based on similar work for an older kernel in the Grsecurity patch.

[JD: fix toshiba-wmi build]
[JD: add htcpen]
[JD: move __initconst where checkscript wants it]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>

platform/chrome: pstore: Move to larger record size.

Accidentally specified a smaller record size, bring it back
to the same size as we had when we used the config file.

Signed-off-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Sameer Nanda <snanda@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

platform/chrome: pstore: probe for ramoops buffer using acpi

In order to handle the firmware placing the ramoops buffer
in a different location than the kernel is configured to look
probe for an ACPI device specified by GOOG9999 acpi id. If
no device is found or the first memory resource is not defined
properly fall back to the configured base and length.

Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Filipe Brandenburger <filbranden@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

platform/chrome: pstore: fix dmi table to match all chrome systems

Turns out that DMI_SYSTEM_VENDOR is actually the native vendor of each
Chromebook/box. I tested the original patch on a Pixel that -- surprise,
has Google as vendor. *facepalm*.

The only other data I can think of to probe on is Google_* in the version
string. Checking with our firmware team, all systems should have this
and nothing else than Chrome hardware should have the coreboot + Google_*
combination to date.

So, we'll switch to this. For future platforms we are going to move to
using an ACPI device to configure this instead of a DMI table (yay!),
so longer-term that will sort itself out.

Signed-off-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Benson Leung <bleung@chromium.org>

platform/chrome: Add pstore platform_device

Add the ramoops pstore device so that we get logs of panics across reboots.

Signed-off-by: Olof Johansson <olof@lixom.net>