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2020-11-13mrc_cache: Move code for triggering memory training into mrc_cacheShelley Chen
Currently the decision of whether or not to use mrc_cache in recovery mode is made within the individual platforms' drivers (ie: fsp2.0, fsp1.1, etc.). As this is not platform specific, but uses common vboot infrastructure, the code can be unified and moved into mrc_cache. The conditions are as follows: 1. If HAS_RECOVERY_MRC_CACHE, use mrc_cache data (unless retrain switch is true) 2. If !HAS_RECOVERY_MRC_CACHE && VBOOT_STARTS_IN_BOOTBLOCK, this means that memory training will occur after verified boot, meaning that mrc_cache will be filled with data from executing RW code. So in this case, we never want to use the training data in the mrc_cache for recovery mode. 3. If !HAS_RECOVERY_MRC_CACHE && VBOOT_STARTS_IN_ROMSTAGE, this means that memory training happens before verfied boot, meaning that the mrc_cache data is generated by RO code, so it is safe to use for a recovery boot. 4. Any platform that does not use vboot should be unaffected. Additionally, we have removed the MRC_CLEAR_NORMAL_CACHE_ON_RECOVERY_RETRAIN config because the mrc_cache driver takes care of invalidating the mrc_cache data for normal mode. If the platform: 1. !HAS_RECOVERY_MRC_CACHE, always invalidate mrc_cache data 2. HAS_RECOVERY_MRC_CACHE, only invalidate if retrain switch is set BUG=b:150502246 BRANCH=None TEST=1. run dut-control power_state:rec_force_mrc twice on lazor ensure that memory retraining happens both times run dut-control power_state:rec twice on lazor ensure that memory retraining happens only first time 2. remove HAS_RECOVERY_MRC_CACHE from lazor Kconfig boot twice to ensure caching of memory training occurred on each boot. Change-Id: I3875a7b4a4ba3c1aa8a3c1507b3993036a7155fc Signed-off-by: Shelley Chen <shchen@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/46855 Reviewed-by: Furquan Shaikh <furquan@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2020-10-28drivers/mrc_cache: Fix size comparison in mrc_cache updateTim Wawrzynczak
`mrc_cache_needs_update` is comparing the "new size" of the MRC data (minus metadata size) to the size including the metadata, which causes the driver to think the data has changed, and so it will rewrite the MRC cache on every boot. This patch removes the metadata size from the comparison. BUG=b:171513942 BRANCH=volteer TEST=1) Memory training data gets written the on a boot where the data was wiped out. 2) Memory training data does not get written back on every subsequent boot. Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org> Change-Id: I7280276f71fdaa492c327b2b7ade8e53e7c59f51 Reviewed-on: https://review.coreboot.org/c/coreboot/+/46824 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Shelley Chen <shchen@google.com> Reviewed-by: Furquan Shaikh <furquan@google.com>
2020-10-20mrc_cache: Remove unnecessary data checksum calculationShelley Chen
When MRC_SAVE_HASH_IN_TPM is selected, we can just use the TPM hash to verify the MRC_CACHE data. Thus, we don't need to calculate the checksum anymore in this case. BUG=b:150502246 BRANCH=None TEST=make sure memory training still works on nami Change-Id: I1db4469da49755805b541f50c7ef2f9cdb749425 Signed-off-by: Shelley Chen <shchen@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/46515 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Furquan Shaikh <furquan@google.com>
2020-10-20mrc_cache: Add tpm_hash_index field to cache_region structShelley Chen
Pull selection of tpm hash index logic into cache_region struct. This CL also enables the storing of the MRC hash into the TPM NVRAM space for both recovery and non-recovery cases. This will affect all platforms with TPM2 enabled and use the MRC_CACHE driver. BUG=b:150502246 BRANCH=None TEST=make sure memory training still works on nami and lazor Change-Id: I1a744d6f40f062ca3aab6157b3747e6c1f6977f9 Signed-off-by: Shelley Chen <shchen@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/46514 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Furquan Shaikh <furquan@google.com>
2020-10-20security/vboot: Make mrc_cache hash functions genericShelley Chen
We need to extend the functionality of the mrc_cache hash functions to work for both recovery and normal mrc_cache data. Updating the API of these functions to pass in an index to identify the hash indices for recovery and normal mode. BUG=b:150502246 BRANCH=None TEST=make sure memory training still works on nami Change-Id: I9c0bb25eafc731ca9c7a95113ab940f55997fc0f Signed-off-by: Shelley Chen <shchen@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/46432 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Furquan Shaikh <furquan@google.com>
2020-10-20mrc_cache: Move mrc_cache_*_hash functions into mrc_cache driverShelley Chen
This CL would remove these calls from fsp 2.0. Platforms that select MRC_STASH_TO_CBMEM, updating the TPM NVRAM space is moved from romstage (when data stashed to CBMEM) to ramstage (when data is written back to SPI flash. BUG=b:150502246 BRANCH=None TEST=make sure memory training still works on nami Change-Id: I3088ca6927c7dbc65386c13e868afa0462086937 Signed-off-by: Shelley Chen <shchen@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/46510 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Furquan Shaikh <furquan@google.com> Reviewed-by: Julius Werner <jwerner@chromium.org>
2020-10-20mrc_cache: Add config MRC_SAVE_HASH_IN_TPMShelley Chen
Use this config to specify whether we want to save a hash of the MRC_CACHE in the TPM NVRAM space. Replace all uses of FSP2_0_USES_TPM_MRC_HASH with MRC_SAVE_HASH_IN_TPM and remove the FSP2_0_USES_TPM_MRC_HASH config. Note that TPM1 platforms will not select MRC_SAVE_HASH_IN_TPM as none of them use FSP2.0 and have recovery MRC_CACHE. BUG=b:150502246 BRANCH=None TEST=emerge-nami coreboot chromeos-bootimage Change-Id: Ic5ffcdba27cb1f09c39c3835029c8d9cc3453af1 Signed-off-by: Shelley Chen <shchen@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/46509 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Furquan Shaikh <furquan@google.com>
2020-10-09mrc_cache: Change mrc_cache_load_current to return size of entryShelley Chen
Modify mrc_cache_load current to return the size of the mrc_cache entry so that caller will know what the actual size of the data returned is. This is needed for ARM devices like trogdor, which need to know the size of the training data when populating the QcLib interface table. BUG=b:150502246 BRANCH=None TEST=./util/abuild/abuild -p none -t GOOGLE_NAMI -x -a Change-Id: Ia314717ad2a7d5232b37a19951c1aecd7f843c27 Signed-off-by: Shelley Chen <shchen@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/46110 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Furquan Shaikh <furquan@google.com>
2020-10-02mrc_cache: Update mrc_cache data in romstageShelley Chen
Previously, we were writing to cbmem after memory training and then writing the training data from cbmem to mrc_cache in ramstage. We were doing this because we were unable to read/write to SPI simultaneously on older x86 chips. Now that newer chips allow for simultaneously reads and writes, we can move the mrc_cache update into romstage. This is beneficial if there is a reboot for some reason after memory training but before the previous mrc_cache_stash_data call originally in ramstage. If this happens, we would lose all the mrc_cache training data in the next boot even though we've already performed the memory training. Added new config BOOT_DEVICE_SPI_FLASH_NO_EARLY_WRITES to accomodate older x86 platforms that don't do mmapping but still want to use the cbmem to store the mrc_cache data in order to write the mrc_cache data back at a later time. We are maintaining the use of cbmem for these older platforms because we have no way of validating the earlier write back to mrc_cache at this time. BUG=b:150502246 BRANCH=None TEST=reboot from ec console. Make sure memory training happens. reboot from ec console. Make sure that we don't do training again. Signed-off-by: Shelley Chen <shchen@google.com> Change-Id: I3430bda45484cb8c2b01ab9614508039dfaac9a3 Reviewed-on: https://review.coreboot.org/c/coreboot/+/44196 Reviewed-by: Furquan Shaikh <furquan@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2020-09-07drivers/mrc_cache: Reduce severity of `region not found` log messageAngel Pons
On autogenerated FMAPs, there's no `UNIFIED_MRC_CACHE` region. The current code will print a spurious error message about it, though. Reduce the log level to BIOS_INFO to avoid confusion. Change-Id: I0961bb2a7d2d81dc5c0d28f6e6c29b320421fc3e Signed-off-by: Angel Pons <th3fanbus@gmail.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/45076 Reviewed-by: Furquan Shaikh <furquan@google.com> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org> Reviewed-by: Christian Walter <christian.walter@9elements.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2020-08-24mrc_cache: Move mrc_cache_stash_data to end of fileShelley Chen
We need to pull update_mrc_cache into mrc_cache_stash_data, so moving to end of the file to make sure update_mrc_cache is defined before. BUG=b:150502246 BRANCH=None TEST=Testing on a nami (x86) device: reboot from ec console. Make sure memory training happens. reboot from ec console. Make sure that we don't do training again. Signed-off-by: Shelley Chen <shchen@google.com> Change-Id: I9e14fec96e9dabceafc2f6f5663fc6f1023f0395 Reviewed-on: https://review.coreboot.org/c/coreboot/+/44195 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Julius Werner <jwerner@chromium.org> Reviewed-by: Furquan Shaikh <furquan@google.com>
2020-08-24mrc_cache: Add mrc_cache fetch functions to support non-x86 platformsShelley Chen
Create two new functions to fetch mrc_cache data (replacing mrc_cache_get_current): - mrc_cache_load_current: fetches the mrc_cache data and drops it into the given buffer. This is useful for ARM platforms where the mmap operation is very expensive. - mrc_cache_mmap_leak: fetch the mrc_cache data and puts it into a given buffer. This is useful for platforms where the mmap operation is a no-op (like x86 platforms). As the name mentions, we are not freeing the memory that we allocated with the mmap, so it is the caller's responsibility to do so. Additionally, we are replacing mrc_cache_latest with mrc_cache_get_latest_slot_info, which does not check the validity of the data when retrieving the current mrc_cache slot. This allows the caller some flexibility in deciding where they want the mrc_cache data stored (either in an mmaped region or at a given address). BUG=b:150502246 BRANCH=None TEST=Testing on a nami (x86) device: reboot from ec console. Make sure memory training happens. reboot from ec console. Make sure that we don't do training again. Signed-off-by: Shelley Chen <shchen@google.com> Change-Id: I259dd4f550719d821bbafa2d445cbae6ea22e988 Reviewed-on: https://review.coreboot.org/c/coreboot/+/44006 Reviewed-by: Furquan Shaikh <furquan@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2020-07-26drivers/mrc_cache: Avoid unused variable assignmentPaul Menzel
Fix the scan-build warning below: CC romstage/drivers/mrc_cache/mrc_cache.o src/drivers/mrc_cache/mrc_cache.c:450:26: warning: Value stored to 'flash' during its initialization is never read const struct spi_flash *flash = boot_device_spi_flash(); ^~~~~ ~~~~~~~~~~~~~~~~~~~~~~~ 1 warning generated. The function can return early before the value is read. Fix this, by getting rid of the variable, as the value is only read once. Change-Id: I3c94b123f4994eed9d7568b63971fd5b1d94bc09 Found-by: scan-build (clang-tools-9 1:9.0.1-12) Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de> Reviewed-on: https://review.coreboot.org/c/coreboot/+/42798 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <siro@das-labor.org>
2020-06-07drivers/mrc_cache: generate debug messages for MRC cache updateJonathan Zhang
When MRC cached data update is performed, messages are written to event log, which is flash based. For system that does not have flash based event log, the messages are lost. Added corresponding BIOS_DEBUG messages. Signed-off-by: Jonathan Zhang <jonzhang@fb.com> Change-Id: I1ef4794151fea7213c8317ddc898b0e37da280b5 Reviewed-on: https://review.coreboot.org/c/coreboot/+/41981 Reviewed-by: Duncan Laurie <dlaurie@chromium.org> Reviewed-by: Michael Niewöhner Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2020-05-11treewide: Remove "this file is part of" linesPatrick Georgi
Stefan thinks they don't add value. Command used: sed -i -e '/file is part of /d' $(git grep "file is part of " |egrep ":( */\*.*\*/\$|#|;#|-- | *\* )" | cut -d: -f1 |grep -v crossgcc |grep -v gcov | grep -v /elf.h |grep -v nvramtool) The exceptions are for: - crossgcc (patch file) - gcov (imported from gcc) - elf.h (imported from GNU's libc) - nvramtool (more complicated header) The removed lines are: - fmt.Fprintln(f, "/* This file is part of the coreboot project. */") -# This file is part of a set of unofficial pre-commit hooks available -/* This file is part of coreboot */ -# This file is part of msrtool. -/* This file is part of msrtool. */ - * This file is part of ncurses, designed to be appended after curses.h.in -/* This file is part of pgtblgen. */ - * This file is part of the coreboot project. - /* This file is part of the coreboot project. */ -# This file is part of the coreboot project. -# This file is part of the coreboot project. -## This file is part of the coreboot project. --- This file is part of the coreboot project. -/* This file is part of the coreboot project */ -/* This file is part of the coreboot project. */ -;## This file is part of the coreboot project. -# This file is part of the coreboot project. It originated in the - * This file is part of the coreinfo project. -## This file is part of the coreinfo project. - * This file is part of the depthcharge project. -/* This file is part of the depthcharge project. */ -/* This file is part of the ectool project. */ - * This file is part of the GNU C Library. - * This file is part of the libpayload project. -## This file is part of the libpayload project. -/* This file is part of the Linux kernel. */ -## This file is part of the superiotool project. -/* This file is part of the superiotool project */ -/* This file is part of uio_usbdebug */ Change-Id: I82d872b3b337388c93d5f5bf704e9ee9e53ab3a9 Signed-off-by: Patrick Georgi <pgeorgi@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/41194 Reviewed-by: HAOUAS Elyes <ehaouas@noos.fr> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2020-05-09vboot: Clean up pre-RAM use of vboot_recovery_mode_enabled()Julius Werner
vboot_recovery_mode_enabled() was recently changed to assert() when it is called before vboot logic has run, because we cannot determine whether we're going to be in recovery mode at that point and we wanted to flush out existing uses that pretended that we could. Turns out there are a bunch of uses like that, and there is some code that is shared across configurations that can and those that can't. This patch cleans them up to either remove checks that cannot return true, or add explicit Kconfig guards to clarify that the code is shared. This means that using a separate recovery MRC cache is no longer supported on boards that use VBOOT_STARTS_IN_ROMSTAGE (this has already been broken with CB:38780, but with this patch those boards will boot again using their normal MRC caches rather than just die). Skipping the MRC cache and always regenerating from scratch in recovery mode is likewise no longer supported for VBOOT_STARTS_IN_ROMSTAGE. For FSP1.1 boards, none of them support VBOOT_STARTS_IN_BOOTBLOCK and that is unlikely to change in the future so we will just hardcode that fact in Kconfig (otherwise, fsp1.1 raminit would also have to be fixed to work around this issue). Signed-off-by: Julius Werner <jwerner@chromium.org> Change-Id: I31bfc7663724fdacab9955224dcaf650d1ec1c3c Reviewed-on: https://review.coreboot.org/c/coreboot/+/39221 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2020-04-06src/drivers: Use SPDX for GPL-2.0-only filesAngel Pons
Done with sed and God Lines. Only done for C-like code for now. Change-Id: I38eaffa391ed5971217ffad74a312b1641e431c9 Signed-off-by: Angel Pons <th3fanbus@gmail.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/40051 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
2020-03-12vboot: remove extraneous vboot_recovery_mode_memory_retrainJoel Kitching
Just call get_recovery_mode_retrain_switch() directly. BUG=b:124141368 TEST=make clean && make test-abuild BRANCH=none Change-Id: Icb88d6862db1782e0218276984e527638b21fd3a Signed-off-by: Joel Kitching <kitching@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/39343 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Julius Werner <jwerner@chromium.org> Reviewed-by: Angel Pons <th3fanbus@gmail.com>
2019-12-15drivers/mrc_cache: Redo indentingMarshall Dawson
Indent continuation lines of an if test farther than its "true" expression to be executed. Change-Id: I3dfa4049761095dcbb6797f1533d6a513e3b503c Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/37720 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-by: Angel Pons <th3fanbus@gmail.com>
2019-10-22AUTHORS: Move src/drivers/[l*-v*] copyrights into AUTHORS fileMartin Roth
As discussed on the mailing list and voted upon, the coreboot project is going to move the majority of copyrights out of the headers and into an AUTHORS file. This will happen a bit at a time, as we'll be unifying license headers at the same time. Updated Authors file is in a separate commit. Signed-off-by: Martin Roth <martin@coreboot.org> Change-Id: Ia0a07df6ca1fdaa2837ce8839057057cbd44d157 Reviewed-on: https://review.coreboot.org/c/coreboot/+/36181 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2019-03-08coreboot: Replace all IS_ENABLED(CONFIG_XXX) with CONFIG(XXX)Julius Werner
This patch is a raw application of find src/ -type f | xargs sed -i -e 's/IS_ENABLED\s*(CONFIG_/CONFIG(/g' Change-Id: I6262d6d5c23cabe23c242b4f38d446b74fe16b88 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/c/coreboot/+/31774 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2019-01-21drivers/spi: Add controller protection typeRizwan Qureshi
Some SPI controllers support both READ and WRITE protection add a variable to the protect API for the callers to specify the kind of protection they want (Read/Write/Both). Also, update the callers and protect API implementation. BUG=None BRANCH=None TEST=test that the mrc cache is protected as expected on soraka. Also tried if the read protection is applied correctly. Change-Id: I093884c4768b08a378f21242ac82e430ac013d15 Signed-off-by: Rizwan Qureshi <rizwan.qureshi@intel.com> Reviewed-on: https://review.coreboot.org/c/30559 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <siro@das-labor.org>
2018-10-08Move compiler.h to commonlibNico Huber
Its spreading copies got out of sync. And as it is not a standard header but used in commonlib code, it belongs into commonlib. While we are at it, always include it via GCC's `-include` switch. Some Windows and BSD quirk handling went into the util copies. We always guard from redefinitions now to prevent further issues. Change-Id: I850414e6db1d799dce71ff2dc044e6a000ad2552 Signed-off-by: Nico Huber <nico.h@gmx.de> Reviewed-on: https://review.coreboot.org/28927 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-01-20drivers/mrc_cache: Always generate an FMAP regionArthur Heymans
This automatically generates an FMAP region for the MRC_CACHE driver which is easier to handle than a cbfsfile. Adds some spaces and more comments to Makefile.inc to improve readability. Tested on Thinkpad x200 with some proof of concept patches. Change-Id: Iaaca36b1123b094ec1bbe5df4fb25660919173ca Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-on: https://review.coreboot.org/23150 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2018-01-19drivers/mrc_cache: Make bootstate for SPI writes variableMarshall Dawson
The default time for writing MRC data to flash is at the exit of BS_DEV_ENUMERATE but this is too early for some implementations. Add an option to Kconfig for allowing a late option to be selected. The timing of the late option is at the entry of BS_OS_RESUME_CHECK. TEST=Select option and inspect console log on Kahlee BUG=b:69614064 Change-Id: Ie7ba9070829d98414ee788e14d1a768145d742ea Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com> Reviewed-on: https://review.coreboot.org/22937 Reviewed-by: Martin Roth <martinroth@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2017-12-24drivers/mrc_cache: Make CACHE_MRC_SETTINGS not selectableArthur Heymans
Don't allow the user to select this manually, since it doesn't build on platforms that don't use it. Don't set the bool value so that it doesn't show as not selected in the .config file of platforms that don't use this. Change-Id: Icf026a297204868d485be270ccee7e0bec0ac73b Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-on: https://review.coreboot.org/22933 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Martin Roth <martinroth@google.com>
2017-12-19drivers/mrc_cache: only add mrc.cache when CACHE_MRC_SETTINGS is setIru Cai
In commit decd0628 (drivers/mrc_cache: move mrc_cache support to drivers) mrc.cache is always added, but CONFIG_MRC_SETTINGS_CACHE_SIZE is not used in Sandy Bridge, which makes mrc.cache have zero size and the machine will fail to boot after the first boot. Change-Id: Iab3ac87e43408ef51f0158f319eb1c8ccfce8a55 Signed-off-by: Iru Cai <mytbk920423@gmail.com> Reviewed-on: https://review.coreboot.org/22925 Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-by: Furquan Shaikh <furquan@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
2017-12-17drivers/mrc_cache: move mrc_cache support to driversAaron Durbin
There's nothing intel-specific about the current mrc_cache support. It's logic manages saving non-volatile areas into the boot media. Therefore, expose it to the rest of the system for any and all to use. BUG=b:69614064 Change-Id: I3b331c82a102f88912a3e10507a70207fb20aecc Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: https://review.coreboot.org/22901 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Furquan Shaikh <furquan@google.com>