Martin Roth (gaumless@gmail.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/8195
-gerrit
commit 2c1cdba6ac682623e14354e51dea0887571ec124 Author: Martin Roth gaumless@gmail.com Date: Sun Jan 11 14:58:47 2015 -0700
FSP platforms: Clear area in CAR for cbmem
cbmem requires that the memory at _car_data_start be cleared or it does not get used.
This patch clears the CAR area used by cbmem. Most of the CAR implementations clear the entire area when setting up the CAR area. The FSP loads the entire are with a pattern instead, so the cbmem area needs to be cleared.
Change-Id: I829ddc26133353a784dfc01729af9b3bf427e889 Signed-off-by: Martin Roth gaumless@gmail.com --- src/drivers/intel/fsp/cache_as_ram.inc | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/src/drivers/intel/fsp/cache_as_ram.inc b/src/drivers/intel/fsp/cache_as_ram.inc index 9e8b2a2..8c04dc7 100644 --- a/src/drivers/intel/fsp/cache_as_ram.inc +++ b/src/drivers/intel/fsp/cache_as_ram.inc @@ -42,6 +42,8 @@ #ifndef CONFIG_CPU_MICROCODE_CBFS_LOC # error "CONFIG_CPU_MICROCODE_CBFS_LOC must be set." #endif +.extern _car_data_start +.extern _car_data_end
#define LHLT_DELAY 0x50000 /* I/O delay between post codes on failure */
@@ -95,6 +97,14 @@ CAR_init_done: movl %esp, %ebp pushl %ebx
+ /* Clear the cbmem CAR memory region. */ + movl $_car_data_start, %edi + movl $_car_data_end, %ecx + sub %edi, %ecx + shr $2, %ecx + xorl %eax, %eax + rep stosl + before_romstage: post_code(0x23)