mrc_cache: Move code for triggering memory training into mrc_cache

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>

1 files changed, 0 insertions, 12 deletions

diff --git a/src/drivers/intel/fsp2_0/memory_init.c b/src/drivers/intel/fsp2_0/memory_init.c
index 68cc1215a5..27e34fef0d 100644
--- a/src/drivers/intel/fsp2_0/memory_init.c
+++ b/src/drivers/intel/fsp2_0/memory_init.c
@@ -92,18 +92,6 @@ static void fsp_fill_mrc_cache(FSPM_ARCH_UPD *arch_upd, uint32_t fsp_version)
 	if (!CONFIG(CACHE_MRC_SETTINGS))
 		return;
 
-	/*
-	 * In recovery mode, force retraining:
-	 * 1. Recovery cache is not supported, or
-	 * 2. Memory retrain switch is set.
-	 */
-	if (vboot_recovery_mode_enabled()) {
-		if (!CONFIG(HAS_RECOVERY_MRC_CACHE))
-			return;
-		if (get_recovery_mode_retrain_switch())
-			return;
-	}
-
 	/* Assume boot device is memory mapped. */
 	assert(CONFIG(BOOT_DEVICE_MEMORY_MAPPED));