diff options
Diffstat (limited to 'src/cpu/x86/sipi_vector.S')
| -rw-r--r-- | src/cpu/x86/sipi_vector.S | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/src/cpu/x86/sipi_vector.S b/src/cpu/x86/sipi_vector.S index bd60c65a88..83606bd920 100644 --- a/src/cpu/x86/sipi_vector.S +++ b/src/cpu/x86/sipi_vector.S @@ -15,6 +15,7 @@ */ #include <cpu/x86/cr.h> +#include <cpu/amd/mtrr.h> /* The SIPI vector is responsible for initializing the APs in the sytem. It * loads microcode, sets up MSRs, and enables caching before calling into @@ -172,6 +173,15 @@ microcode_done: mov msr_count, %ebx test %ebx, %ebx jz 1f + +#if IS_ENABLED(CONFIG_X86_AMD_FIXED_MTRRS) + /* Allow modification of RdDram and WrDram bits */ + mov $SYSCFG_MSR, %ecx + rdmsr + or $SYSCFG_MSR_MtrrFixDramModEn, %eax + wrmsr +#endif + load_msr: mov (%edi), %ecx mov 4(%edi), %eax @@ -181,6 +191,13 @@ load_msr: dec %ebx jnz load_msr +#if IS_ENABLED(CONFIG_X86_AMD_FIXED_MTRRS) + mov $SYSCFG_MSR, %ecx + rdmsr + and $~SYSCFG_MSR_MtrrFixDramModEn, %eax + wrmsr +#endif + 1: /* Enable caching. */ mov %cr0, %eax |