From 1b12d785da70578b4954c58b9a38285fcd5d778c Mon Sep 17 00:00:00 2001 From: Subrata Banik Date: Thu, 8 Jul 2021 12:50:42 +0530 Subject: [PATCH] soc/intel/common: Use SPR for backing up data way and eviction mask This patch replaces the usage of GPR (General Purpose Registers) like ECX and EBX for backing up data way and non-eviction mask with SPR (Special Purpose Registers) EDI and ESI. Purpose of this change is to ensure the safety while developers might use ECX often while doing rdmsr/wrmsr rather than making use of EDI. TEST=Able to boot JSL and TGL platform without any hang using eNEM. Change-Id: I12e0cb7bb050e4f7b17ecf30108db335d1d82ab7 Signed-off-by: Subrata Banik Reviewed-on: https://review.coreboot.org/c/coreboot/+/56161 Reviewed-by: Angel Pons Reviewed-by: Tim Wawrzynczak Reviewed-by: Arthur Heymans Tested-by: build bot (Jenkins) --- src/soc/intel/common/block/cpu/car/cache_as_ram.S | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/src/soc/intel/common/block/cpu/car/cache_as_ram.S b/src/soc/intel/common/block/cpu/car/cache_as_ram.S index 74957aba9f..784e8ca0ae 100644 --- a/src/soc/intel/common/block/cpu/car/cache_as_ram.S +++ b/src/soc/intel/common/block/cpu/car/cache_as_ram.S @@ -514,15 +514,15 @@ find_llc_subleaf: subl $0x01, %eax set_eviction_mask: - mov %ebx, %ecx /* back up number of ways */ - mov %eax, %ebx /* back up the non-eviction mask*/ + mov %ebx, %edi /* back up number of ways */ + mov %eax, %esi /* back up the non-eviction mask*/ #if CONFIG(CAR_HAS_SF_MASKS) - mov %ecx, %edi /* use number of ways to prepare SF mask */ /* * SF mask is programmed with the double number of bits than * the number of ways */ mov $0x01, %eax + mov %edi, %ecx shl %cl, %eax shl %cl, %eax subl $0x01, %eax /* contains SF mask */ @@ -533,7 +533,6 @@ set_eviction_mask: movl $IA32_CR_SF_QOS_MASK_1, %ecx xorl %edx, %edx wrmsr - mov %edi, %ecx /* restore number of ways */ #endif /* * Program MSR 0xC91 IA32_L3_MASK_1 @@ -542,10 +541,11 @@ set_eviction_mask: * - If this bit is '1' - the way is not protected from eviction */ mov $0x1, %eax + mov %edi, %ecx shl %cl, %eax subl $0x01, %eax mov %eax, %ecx - mov %ebx, %eax + mov %esi, %eax xor $~0, %eax /* invert 32 bits */ and %ecx, %eax @@ -558,7 +558,7 @@ set_eviction_mask: * - If this bit is '0' - the way is protected from eviction * - If this bit is '1' - the way is not protected from eviction */ - mov %ebx, %eax + mov %esi, %eax movl $IA32_L3_MASK_2, %ecx xorl %edx, %edx wrmsr