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| author | Marc Jones <marcj303@gmail.com> | 2017-02-24 16:40:41 -0700 |
|---|---|---|
| committer | Kyösti Mälkki <kyosti.malkki@gmail.com> | 2017-07-15 16:08:38 +0000 |
| commit | 7f5d0f3c922ee22f7347d1b5d275508b8b9e8ce9 (patch) | |
| tree | 455f455ac5258fb12bab78436c8f4a62081e9112 /src/vendorcode/amd/pi/00730F01 | |
| parent | 8c81c6ac436c8eac0e312cd2a34133d4a7f5d991 (diff) | |
| download | coreboot-7f5d0f3c922ee22f7347d1b5d275508b8b9e8ce9.tar.xz | |
vendorcode/amd/pi: Clarify CAR disable
Clean up commentary on AMD_DISABLE_STACK to be clear that
it does a wbinvd to preserve coreboot CBMEM and
value of car_migrated.
Change-Id: I1265ed3d1bdf4b22f1a56f68bc53e18cfadc44b2
Signed-off-by: Marc Jones <marcj303@gmail.com>
Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/19269
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src/vendorcode/amd/pi/00730F01')
| -rw-r--r-- | src/vendorcode/amd/pi/00730F01/binaryPI/gcccar.inc | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/src/vendorcode/amd/pi/00730F01/binaryPI/gcccar.inc b/src/vendorcode/amd/pi/00730F01/binaryPI/gcccar.inc index 2c51eb1fe8..1ad87c74f3 100644 --- a/src/vendorcode/amd/pi/00730F01/binaryPI/gcccar.inc +++ b/src/vendorcode/amd/pi/00730F01/binaryPI/gcccar.inc @@ -383,6 +383,13 @@ fam16_enable_stack_hook_exit: ; Return any family specific controls to their 'standard' ; settings for using cache with main memory. ; +; Note: Customized for coreboot: +; A wbinvd is used to send cache to memory. The existing stack is preserved +; at its original location and additional information is preserved (e.g. +; coreboot CAR globals, heap structures, etc.). This implementation should +; NOT be used with S3 resume IF the stack/cache area is not reserved and +; over system memory. +; ; Inputs: ; ESI - [31:24] flags; [15:8]= Node#; [7:0]= core# ; Outputs: @@ -602,8 +609,13 @@ fam16_disable_stack_remote_read_exit: _RDMSR btr $INVD_WBINVD, %eax # Disable INVD -> WBINVD conversion _WRMSR - wbinvd # Clear the cache tag RAMs - #invd + + #-------------------------------------------------------------------------- + # Send cache to memory. Preserve stack and coreboot CAR globals. + # This shouldn't be used with S3 resume IF the stack/cache area is + # not reserved and over system memory. + #-------------------------------------------------------------------------- + wbinvd #Do Standard Family 16 work mov $HWCR, %ecx # MSR:C001_0015h @@ -1261,8 +1273,17 @@ ClearTheStack: # Stack base is in SS, stack pointer is .endm /***************************************************************************** -* AMD_DISABLE_STACK: Destroy the stack inside the cache. This routine -* should only be executed on the BSP +* AMD_DISABLE_STACK: Implementation is modified for coreboot from +* the original AMD intent. A WBINVD is used in the HOOK +* to send dirty cache contents to DRAM backing before +* disabling cache-as-ram. This is not safe for S3 resume. +* +* todo: +* * rework PI/AGESA source to set DRAM to UC to send +* writes directly to memory +* * move DCACHE_BASE or use postcar stage for teardown +* to eliminate car_migrated problem that will occur +* after wbinvd is changed back to invd * * In: * none |