google/chromeos/vboot2: defer clearing rec mode switch

Certain platforms query the recovery mode switch more than just within
vboot during the boot flow. Therefore, it's important that the first call to
get_recovery_mode_switch() is consistent through memory training because
certain platforms use the recovery mode switch to take different action
for memory training. Therefore, defer the clearing of the rec mode
switch to a place when it's known that memory is up and online.

BUG=chrome-os-partner:44827
BRANCH=glados
TEST=Three finger salute is honored on chell by retraining memory.

Change-Id: I26ea51de7ffa2fe75b9ef1401fe92f9aec2b4567
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 6b0de9369242e50c7ff3b164cf1ced0642c7b087
Original-Change-Id: Ia7709c7346d1222e314bf3ac7e4335a63e9a5144
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/325120
Original-Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: https://review.coreboot.org/13604
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>

2 files changed, 11 insertions, 1 deletions

diff --git a/src/vendorcode/google/chromeos/vboot2/vboot_handoff.c b/src/vendorcode/google/chromeos/vboot2/vboot_handoff.c
index dbcc4da012..c89e9a0373 100644
--- a/src/vendorcode/google/chromeos/vboot2/vboot_handoff.c
+++ b/src/vendorcode/google/chromeos/vboot2/vboot_handoff.c
@@ -152,6 +152,17 @@ void vboot_fill_handoff(void)
 
 	/* needed until we finish transtion to vboot2 for kernel verification */
 	fill_vboot_handoff(vh, sd);
+
+	/*
+	 * The recovery mode switch is cleared (typically backed by EC) here
+	 * to allow multiple queries to get_recovery_mode_switch() and have
+	 * them return consistent results during the verified boot path as well
+	 * as dram initialization. x86 systems ignore the saved dram settings
+	 * in the recovery path in order to start from a clean slate. Therefore
+	 * clear the state here since this function is called when memory
+	 * is known to be up.
+	 */
+	clear_recovery_mode_switch();
 }
 
 /*
diff --git a/src/vendorcode/google/chromeos/vboot2/vboot_logic.c b/src/vendorcode/google/chromeos/vboot2/vboot_logic.c
index fec368c590..a4829c097e 100644
--- a/src/vendorcode/google/chromeos/vboot2/vboot_logic.c
+++ b/src/vendorcode/google/chromeos/vboot2/vboot_logic.c
@@ -316,7 +316,6 @@ void verstage_main(void)
 		ctx.flags |= VB2_CONTEXT_FORCE_DEVELOPER_MODE;
 
 	if (get_recovery_mode_switch()) {
-		clear_recovery_mode_switch();
 		ctx.flags |= VB2_CONTEXT_FORCE_RECOVERY_MODE;
 		if (IS_ENABLED(CONFIG_VBOOT_DISABLE_DEV_ON_RECOVERY))
 			ctx.flags |= VB2_DISABLE_DEVELOPER_MODE;