Patrick Georgi has submitted this change. ( https://review.coreboot.org/c/coreboot/+/40437 )
Change subject: intel/stm: Place resource list right below MSEG ......................................................................
intel/stm: Place resource list right below MSEG
Suggested by Nico Huber in CB:38765.
This placement makes the address calculation simpler and makes its location indepedent of the number of CPUs.
As part of the change in the BIOS resource list address calculation, the `size` variable was factored out of the conditional in line 361, thus eliminating the else.
Change-Id: I9ee2747474df02b0306530048bdec75e95413b5d Signed-off-by: Eugene D Myers cedarhouse@comcast.net Reviewed-on: https://review.coreboot.org/c/coreboot/+/40437 Reviewed-by: Nico Huber nico.h@gmx.de Reviewed-by: Angel Pons th3fanbus@gmail.com Tested-by: build bot (Jenkins) no-reply@coreboot.org --- M src/cpu/x86/smm/smm_module_loader.c M src/security/intel/stm/StmPlatformSmm.c 2 files changed, 8 insertions(+), 17 deletions(-)
Approvals: build bot (Jenkins): Verified Nico Huber: Looks good to me, approved Angel Pons: Looks good to me, but someone else must approve
diff --git a/src/cpu/x86/smm/smm_module_loader.c b/src/cpu/x86/smm/smm_module_loader.c index bdcf283..c08e833 100644 --- a/src/cpu/x86/smm/smm_module_loader.c +++ b/src/cpu/x86/smm/smm_module_loader.c @@ -307,13 +307,13 @@ /* The SMM module is placed within the provided region in the following * manner: * +-----------------+ <- smram + size - * | stacks | - * +-----------------+ <- smram + size - total_stack_size - * | fxsave area | - * +-----------------+ <- smram + size - total_stack_size - fxsave_size * | BIOS resource | * | list (STM) | - * +-----------------+ <- .. - CONFIG_BIOS_RESOURCE_LIST_SIZE + * +-----------------+ <- smram + size - CONFIG_BIOS_RESOURCE_LIST_SIZE + * | stacks | + * +-----------------+ <- .. - total_stack_size + * | fxsave area | + * +-----------------+ <- .. - total_stack_size - fxsave_size * | ... | * +-----------------+ <- smram + handler_size + SMM_DEFAULT_SIZE * | handler | @@ -354,11 +354,10 @@
/* Stacks start at the top of the region. */ base = smram; + base += size;
if (CONFIG(STM)) - base += size - CONFIG_MSEG_SIZE; // take out the mseg - else - base += size; + base -= CONFIG_MSEG_SIZE + CONFIG_BIOS_RESOURCE_LIST_SIZE;
params->stack_top = base;
@@ -388,9 +387,6 @@ /* Does the required amount of memory exceed the SMRAM region size? */ total_size = total_stack_size + handler_size; total_size += fxsave_size + SMM_DEFAULT_SIZE; - /* Account for the BIOS resource list */ - if (CONFIG(STM)) - total_size += CONFIG_BIOS_RESOURCE_LIST_SIZE;
if (total_size > size) return -1; diff --git a/src/security/intel/stm/StmPlatformSmm.c b/src/security/intel/stm/StmPlatformSmm.c index 45db0e0..248ccc0 100644 --- a/src/security/intel/stm/StmPlatformSmm.c +++ b/src/security/intel/stm/StmPlatformSmm.c @@ -177,12 +177,7 @@
// need to create the BIOS resource list once // first calculate the location in SMRAM - addr_calc = (mseg - (CONFIG_SMM_MODULE_STACK_SIZE * num_cpus)); - - if (CONFIG(SSE)) - addr_calc -= FXSAVE_SIZE * num_cpus; - - addr_calc -= CONFIG_BIOS_RESOURCE_LIST_SIZE; + addr_calc = mseg - CONFIG_BIOS_RESOURCE_LIST_SIZE; stm_resource_heap = (uint8_t *) addr_calc; printk(BIOS_DEBUG, "STM: stm_resource_heap located at %p\n", stm_resource_heap);