[S] Change in coreboot[master]: cpu/x86/smm/module_loader: Fix ASEG loading

[Arthur Heymans (Code Review)]

Arthur Heymans has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/69233 )

Change subject: cpu/x86/smm/module_loader: Fix ASEG loading
......................................................................

cpu/x86/smm/module_loader: Fix ASEG loading

This code was never tested with SSE enabled. Now qemu enables it and
FX_SAVE encroaches on the save states. Without SSE enabled the handler
just happened to be aligned downwards enough to have the save states
fit. With SSE enabled that's not the case. The proper fix is to give the
code setting up stubs the right base address, which is the same as for
the TSEG codepath.

Change-Id: I45355efb274c6ddd09a6fb57743d2f6a5b53d209
Signed-off-by: Arthur Heymans 
---
M src/cpu/x86/smm/smm_module_loader.c
1 file changed, 23 insertions(+), 12 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/33/69233/1

diff --git a/src/cpu/x86/smm/smm_module_loader.c b/src/cpu/x86/smm/smm_module_loader.c
index 71d49ab..6f334a2 100644
--- a/src/cpu/x86/smm/smm_module_loader.c
+++ b/src/cpu/x86/smm/smm_module_loader.c
@@ -409,6 +409,11 @@
 int smm_load_module(const uintptr_t smram_base, const size_t smram_size,
    	    struct smm_loader_params *params)
 {
+	if (CONFIG(SMM_ASEG) && (smram_base != SMM_BASE || smram_size != SMM_CODE_SEGMENT_SIZE)) {
+		printk(BIOS_ERR, "SMM base & size are 0x%lx, 0x%zx, but must be 0x%x, 0x%x\n",
+		       smram_base, smram_size, SMM_BASE, SMM_CODE_SEGMENT_SIZE);
+		return -1;
+	}
    /*
     * Place in .bss to reduce stack usage.
     * TODO: once CPU_INFO_V2 is used everywhere, use smaller stack for APs and move
@@ -457,18 +462,7 @@
    if (append_and_check_region(smram, handler, region_list, "HANDLER"))
    	return -1;

-	uintptr_t stub_segment_base;
-
-	if (CONFIG(SMM_TSEG)) {
-		stub_segment_base = handler_base - SMM_CODE_SEGMENT_SIZE;
-	} else if (CONFIG(SMM_ASEG)) {
-		stub_segment_base = smram_base;
-		if (smram_base != SMM_BASE || smram_size != SMM_CODE_SEGMENT_SIZE) {
-			printk(BIOS_ERR, "SMM base & size are 0x%lx, 0x%zx, but must be 0x%x, 0x%x\n",
-			       smram_base, smram_size, SMM_BASE, SMM_CODE_SEGMENT_SIZE);
-			return -1;
-		}
-	}
+	uintptr_t stub_segment_base = handler_base - SMM_CODE_SEGMENT_SIZE;

if (!smm_create_map(stub_segment_base, params->num_concurrent_save_states, params)) {
    	printk(BIOS_ERR, "%s: Error creating CPU map\n", __func__);