Aaron Durbin has submitted this change. ( https://review.coreboot.org/c/coreboot/+/40922 )
Change subject: src/soc/amd/picasso: Add methods to save and restore MTRRs ......................................................................
src/soc/amd/picasso: Add methods to save and restore MTRRs
FSP AGESA overrides the MTRRs that coreboot set up. Until this is fixed we need to save and restore the MTRRs to undo what AGESA did.
Once AGESA is fixed, we can delete these files.
BUG=b:155426691, b:147042464 TEST=Boot trembyle and see MTRRs being modified Saving Variable MTRR 0: Base: 0x00000000 0xff000005, Mask: 0x0000ffff 0xff000800 Saving Variable MTRR 1: Base: 0x00000000 0x08070006, Mask: 0x0000ffff 0xffff0800 Saving Variable MTRR 2: Base: 0x00000000 0x00000000, Mask: 0x00000000 0x00000000 Saving Variable MTRR 3: Base: 0x00000000 0x00000000, Mask: 0x00000000 0x00000000 Saving Variable MTRR 4: Base: 0x00000000 0x00000000, Mask: 0x00000000 0x00000000 Saving Variable MTRR 5: Base: 0x00000000 0x00000000, Mask: 0x00000000 0x00000000 Saving Variable MTRR 6: Base: 0x00000000 0x00000000, Mask: 0x00000000 0x00000000 Saving Variable MTRR 7: Base: 0x00000000 0x00000000, Mask: 0x00000000 0x00000000 Saving Fixed MTRR 0: 0x00000000 0x00000000 Saving Fixed MTRR 1: 0x00000000 0x00000000 Saving Fixed MTRR 2: 0x00000000 0x00000000 Saving Fixed MTRR 3: 0x00000000 0x00000000 Saving Fixed MTRR 4: 0x00000000 0x00000000 Saving Fixed MTRR 5: 0x00000000 0x00000000 Saving Fixed MTRR 6: 0x00000000 0x00000000 Saving Fixed MTRR 7: 0x00000000 0x00000000 Saving Fixed MTRR 8: 0x00000000 0x00000000 Saving Fixed MTRR 9: 0x00000000 0x00000000 Saving Fixed MTRR 10: 0x00000000 0x00000000 Saving Default Type MTRR: 0x00000000 0x00000800 Saving SYS_CFG: 0x00000000 0x00000800 ... MSR 0x200 was modified: 0x00000000 0x00000006 MSR 0x201 was modified: 0x0000ffff 0x80000800 MSR 0x202 was modified: 0x00000000 0x80000006 MSR 0x203 was modified: 0x0000ffff 0xc0000800 MSR 0x204 was modified: 0x00000000 0xc0000006 MSR 0x205 was modified: 0x0000ffff 0xf0000800 MSR 0x250 was modified: 0x06060606 0x06060606 MSR 0x258 was modified: 0x06060606 0x06060606 SYS_CFG was modified: 0x00000000 0x00740000
Signed-off-by: Raul E Rangel rrangel@chromium.org Change-Id: I6048b25bd8a32904031ca23953f9726754b5a294 Reviewed-on: https://review.coreboot.org/c/coreboot/+/40922 Reviewed-by: Furquan Shaikh furquan@google.com Reviewed-by: Aaron Durbin adurbin@chromium.org Tested-by: build bot (Jenkins) no-reply@coreboot.org --- M src/soc/amd/picasso/Makefile.inc A src/soc/amd/picasso/include/soc/mtrr.h A src/soc/amd/picasso/mtrr.c 3 files changed, 123 insertions(+), 0 deletions(-)
Approvals: build bot (Jenkins): Verified Aaron Durbin: Looks good to me, approved Furquan Shaikh: Looks good to me, approved
diff --git a/src/soc/amd/picasso/Makefile.inc b/src/soc/amd/picasso/Makefile.inc index c7b6fb8..40275ee 100644 --- a/src/soc/amd/picasso/Makefile.inc +++ b/src/soc/amd/picasso/Makefile.inc @@ -31,6 +31,7 @@ romstage-$(CONFIG_HAVE_SMI_HANDLER) += smi_util.c romstage-y += soc_util.c romstage-y += psp.c +romstage-y += mtrr.c
verstage-y += gpio.c verstage-y += i2c.c diff --git a/src/soc/amd/picasso/include/soc/mtrr.h b/src/soc/amd/picasso/include/soc/mtrr.h new file mode 100644 index 0000000..4372ca4 --- /dev/null +++ b/src/soc/amd/picasso/include/soc/mtrr.h @@ -0,0 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* This file is part of the coreboot project. */ + +#ifndef __PICASSO_MTRR_H__ +#define __PICASSO_MTRR_H__ + +void picasso_save_mtrrs(void); +void picasso_restore_mtrrs(void); + +#endif /* __PICASSO_MTRR_H__ */ diff --git a/src/soc/amd/picasso/mtrr.c b/src/soc/amd/picasso/mtrr.c new file mode 100644 index 0000000..fe142f8 --- /dev/null +++ b/src/soc/amd/picasso/mtrr.c @@ -0,0 +1,112 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* This file is part of the coreboot project. */ + +#include <assert.h> +#include <commonlib/bsd/helpers.h> +#include <console/console.h> +#include <cpu/x86/mtrr.h> +#include <cpu/amd/mtrr.h> +#include <soc/mtrr.h> + +/* Picasso defines 8 Variable MTRRs */ +#define MAX_VARIABLE_MTRRS 8 +#define SYS_CFG_MTRR_BITS ( \ +SYSCFG_MSR_TOM2WB | \ +SYSCFG_MSR_TOM2En | \ +SYSCFG_MSR_MtrrVarDramEn | \ +SYSCFG_MSR_MtrrFixDramModEn | \ +SYSCFG_MSR_MtrrFixDramEn \ +) + +static const unsigned int fixed_mtrr_offsets[] = { + MTRR_FIX_64K_00000, + MTRR_FIX_16K_80000, + MTRR_FIX_16K_A0000, + MTRR_FIX_4K_C0000, + MTRR_FIX_4K_C8000, + MTRR_FIX_4K_D0000, + MTRR_FIX_4K_D8000, + MTRR_FIX_4K_E0000, + MTRR_FIX_4K_E8000, + MTRR_FIX_4K_F0000, + MTRR_FIX_4K_F8000, +}; + +static int mtrrs_saved; +static msr_t sys_cfg; +static msr_t mtrr_def; +static msr_t mtrr_base[MAX_VARIABLE_MTRRS]; +static msr_t mtrr_mask[MAX_VARIABLE_MTRRS]; +static msr_t fixed_mtrrs[ARRAY_SIZE(fixed_mtrr_offsets)]; + +void picasso_save_mtrrs(void) +{ + unsigned int i; + int mtrrs; + + mtrrs = get_var_mtrr_count(); + + ASSERT_MSG(mtrrs == MAX_VARIABLE_MTRRS, "Unexpected number of MTRRs\n"); + + for (i = 0; i < MAX_VARIABLE_MTRRS; ++i) { + mtrr_base[i] = rdmsr(MTRR_PHYS_BASE(i)); + mtrr_mask[i] = rdmsr(MTRR_PHYS_MASK(i)); + printk(BIOS_DEBUG, + "Saving Variable MTRR %d: Base: 0x%08x 0x%08x, Mask: 0x%08x 0x%08x\n", i, + mtrr_base[i].hi, mtrr_base[i].lo, mtrr_mask[i].hi, mtrr_mask[i].lo); + } + + for (i = 0; i < ARRAY_SIZE(fixed_mtrr_offsets); ++i) { + fixed_mtrrs[i] = rdmsr(fixed_mtrr_offsets[i]); + printk(BIOS_DEBUG, "Saving Fixed MTRR %u: 0x%08x 0x%08x\n", i, + fixed_mtrrs[i].hi, fixed_mtrrs[i].lo); + } + + mtrr_def = rdmsr(MTRR_DEF_TYPE_MSR); + printk(BIOS_DEBUG, "Saving Default Type MTRR: 0x%08x 0x%08x\n", mtrr_def.hi, + mtrr_def.lo); + + sys_cfg = rdmsr(SYSCFG_MSR); + printk(BIOS_DEBUG, "Saving SYS_CFG: 0x%08x 0x%08x\n", mtrr_def.hi, mtrr_def.lo); + + mtrrs_saved = 1; +} + +static void update_if_changed(unsigned int offset, msr_t expected) +{ + msr_t tmp = rdmsr(offset); + if (tmp.lo == expected.lo && tmp.hi == expected.hi) + return; + + printk(BIOS_INFO, "MSR %#x was modified: 0x%08x 0x%08x\n", offset, tmp.hi, tmp.lo); + wrmsr(offset, expected); +} + +void picasso_restore_mtrrs(void) +{ + unsigned int i; + msr_t tmp_sys_cfg; + + ASSERT_MSG(mtrrs_saved, "Must save MTRRs before restoring.\n"); + + for (i = 0; i < MAX_VARIABLE_MTRRS; ++i) { + update_if_changed(MTRR_PHYS_BASE(i), mtrr_base[i]); + update_if_changed(MTRR_PHYS_MASK(i), mtrr_mask[i]); + } + + for (i = 0; i < ARRAY_SIZE(fixed_mtrr_offsets); ++i) + update_if_changed(fixed_mtrr_offsets[i], fixed_mtrrs[i]); + + update_if_changed(MTRR_DEF_TYPE_MSR, mtrr_def); + + tmp_sys_cfg = rdmsr(SYSCFG_MSR); + + /* We only care about the MTRR bits in the SYSCFG register */ + if ((tmp_sys_cfg.lo & SYS_CFG_MTRR_BITS) != (sys_cfg.lo & SYS_CFG_MTRR_BITS)) { + printk(BIOS_INFO, "SYS_CFG was modified: 0x%08x 0x%08x\n", tmp_sys_cfg.hi, + tmp_sys_cfg.lo); + tmp_sys_cfg.lo &= ~SYS_CFG_MTRR_BITS; + tmp_sys_cfg.lo |= (sys_cfg.lo & SYS_CFG_MTRR_BITS); + wrmsr(SYSCFG_MSR, tmp_sys_cfg); + } +}