commit dd549e117588472d11b10e0b1287a0e19377b844
author Raul E Rangel <rrangel@chromium.org> Mon Jun 25 14:22:27 2018 -0600
committer Martin Roth <martinroth@google.com> Wed Jun 27 22:11:11 2018 +0000
tree 9eba7c4af647c19091eeb80a0a53773e0d7dbe07
parent c57a273d4ccc409e0ae52d8bd09e42d7c87e0aff

smm: Clear SMRAM when debugging

This makes it easier to spot unused RAM.

BUG=b:80539294
TEST=built and tested on grunt. Verified unused memory was set to 0xcdcdcdcd

Change-Id: I335eaf642bd8526f31819eaac95ce80c2df3c300
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Reviewed-on: https://review.coreboot.org/27227
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>

src/cpu/x86/smm/smm_module_loader.c

diff --git a/src/cpu/x86/smm/smm_module_loader.c b/src/cpu/x86/smm/smm_module_loader.c
index 3d7952f..e92fa05 100644
--- a/src/cpu/x86/smm/smm_module_loader.c
+++ b/src/cpu/x86/smm/smm_module_loader.c
@@ -346,6 +346,10 @@
 	if (rmodule_parse(&_binary_smm_start, &smm_mod))
 		return -1;
 
+	/* Clear SMM region */
+	if (IS_ENABLED(CONFIG_DEBUG_SMI))
+		memset(smram, 0xcd, size);
+
 	total_stack_size = params->per_cpu_stack_size *
 			   params->num_concurrent_stacks;