diff options
| author | Tim Wawrzynczak <twawrzynczak@chromium.org> | 2020-09-01 16:11:48 -0600 |
|---|---|---|
| committer | Patrick Georgi <pgeorgi@google.com> | 2020-09-08 05:25:34 +0000 |
| commit | 0cded1f116ed669b6b2b0c8703863691f9957c65 (patch) | |
| tree | 83d9280b8d6aa5458cdf91f771c914989425d4c4 /src/soc | |
| parent | 4cba419676de40c76e4979957baf6039da8b8bf5 (diff) | |
soc/intel/tigerlake: Add SMRR Locking support
The SMRR MSRs can be locked, so that a further write to them will cause
a #GP. This patch adds that functionality, but since the MSR is a
core-level register, it must only be done once per core; if the SoC has
hyperthreading enabled, then attempting to write the SMRR Lock bit on
the primary thread will cause a #GP when the secondary (sibling) thread
attempts to also write to this MSR.
BUG=b:164489598
TEST=Boot into OS, verify using `iotools rdmsr` that all threads have
the Lock bit set.
Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: I4ae7c7f703bdf090144637d071eb810617d9e309
Reviewed-on: https://review.coreboot.org/c/coreboot/+/45013
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kane Chen <kane.chen@intel.com>
Reviewed-by: Caveh Jalali <caveh@chromium.org>
Reviewed-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Diffstat (limited to 'src/soc')
| -rw-r--r-- | src/soc/intel/tigerlake/Kconfig | 1 | ||||
| -rw-r--r-- | src/soc/intel/tigerlake/smmrelocate.c | 17 |
2 files changed, 18 insertions, 0 deletions
diff --git a/src/soc/intel/tigerlake/Kconfig b/src/soc/intel/tigerlake/Kconfig index 182c5ad49f..cdec3ef999 100644 --- a/src/soc/intel/tigerlake/Kconfig +++ b/src/soc/intel/tigerlake/Kconfig @@ -16,6 +16,7 @@ config CPU_SPECIFIC_OPTIONS select BOOT_DEVICE_SUPPORTS_WRITES select CACHE_MRC_SETTINGS select CPU_INTEL_COMMON + select CPU_INTEL_COMMON_HYPERTHREADING select CPU_INTEL_FIRMWARE_INTERFACE_TABLE select FSP_COMPRESS_FSP_S_LZ4 select FSP_M_XIP diff --git a/src/soc/intel/tigerlake/smmrelocate.c b/src/soc/intel/tigerlake/smmrelocate.c index bbdcb68b10..e75e884464 100644 --- a/src/soc/intel/tigerlake/smmrelocate.c +++ b/src/soc/intel/tigerlake/smmrelocate.c @@ -9,6 +9,7 @@ #include <cpu/x86/msr.h> #include <cpu/x86/mtrr.h> #include <cpu/x86/smm.h> +#include <cpu/intel/common/common.h> #include <cpu/intel/em64t101_save_state.h> #include <cpu/intel/smm_reloc.h> #include <console/console.h> @@ -137,8 +138,24 @@ void smm_relocation_handler(int cpu, uintptr_t curr_smbase, /* Make appropriate changes to the save state map. */ update_save_state(cpu, curr_smbase, staggered_smbase, relo_params); + /* + * The SMRR MSRs are core-level registers, so if two threads that share + * a core try to both set the lock bit (in the same physical register), + * a #GP will be raised on the second write to that register (which is + * exactly what the lock is supposed to do), therefore secondary threads + * should exit here. + */ + if (intel_ht_sibling()) + return; + /* Write SMRR MSRs based on indicated support. */ mtrr_cap = rdmsr(MTRR_CAP_MSR); + + /* Set Lock bit if supported */ + if (mtrr_cap.lo & SMRR_LOCK_SUPPORTED) + relo_params->smrr_mask.lo |= SMRR_PHYS_MASK_LOCK; + + /* Write SMRRs if supported */ if (mtrr_cap.lo & SMRR_SUPPORTED) write_smrr(relo_params); } |