| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* This file is part of the coreboot project. */ |
| |
| #define __SIMPLE_DEVICE__ |
| |
| #include <assert.h> |
| #include <stdint.h> |
| #include <console/console.h> |
| #include <cpu/x86/msr.h> |
| #include <cpu/x86/smm.h> |
| #include <cpu/amd/msr.h> |
| #include <cpu/amd/mtrr.h> |
| #include <cbmem.h> |
| #include <arch/bert_storage.h> |
| #include <soc/northbridge.h> |
| #include <soc/iomap.h> |
| #include <amdblocks/acpimmio.h> |
| |
| #if CONFIG(ACPI_BERT) |
| #if CONFIG_SMM_TSEG_SIZE == 0x0 |
| #define BERT_REGION_MAX_SIZE 0x100000 |
| #else |
| /* SMM_TSEG_SIZE must stay on a boundary appropriate for its granularity */ |
| #define BERT_REGION_MAX_SIZE CONFIG_SMM_TSEG_SIZE |
| #endif |
| #else |
| #define BERT_REGION_MAX_SIZE 0 |
| #endif |
| |
| void bert_reserved_region(void **start, size_t *size) |
| { |
| if (CONFIG(ACPI_BERT)) |
| *start = cbmem_top(); |
| else |
| *start = NULL; |
| *size = BERT_REGION_MAX_SIZE; |
| } |
| |
| void *cbmem_top_chipset(void) |
| { |
| msr_t tom = rdmsr(TOP_MEM); |
| |
| if (!tom.lo) |
| return 0; |
| |
| /* 8MB alignment to keep MTRR usage low */ |
| return (void *)ALIGN_DOWN(restore_top_of_low_cacheable() |
| - CONFIG_SMM_TSEG_SIZE |
| - BERT_REGION_MAX_SIZE, 8*MiB); |
| } |
| |
| static uintptr_t smm_region_start(void) |
| { |
| return (uintptr_t)cbmem_top() + BERT_REGION_MAX_SIZE; |
| } |
| |
| static size_t smm_region_size(void) |
| { |
| return CONFIG_SMM_TSEG_SIZE; |
| } |
| |
| /* |
| * For data stored in TSEG, ensure TValid is clear so R/W access can reach |
| * the DRAM when not in SMM. |
| */ |
| static void clear_tvalid(void) |
| { |
| msr_t hwcr = rdmsr(HWCR_MSR); |
| msr_t mask = rdmsr(SMM_MASK_MSR); |
| int tvalid = !!(mask.lo & SMM_TSEG_VALID); |
| |
| if (hwcr.lo & SMM_LOCK) { |
| if (!tvalid) /* not valid but locked means still accessible */ |
| return; |
| |
| printk(BIOS_ERR, "Error: can't clear TValid, already locked\n"); |
| return; |
| } |
| |
| mask.lo &= ~SMM_TSEG_VALID; |
| wrmsr(SMM_MASK_MSR, mask); |
| } |
| |
| void smm_region(uintptr_t *start, size_t *size) |
| { |
| static int once; |
| |
| *start = smm_region_start(); |
| *size = smm_region_size(); |
| |
| if (!once) { |
| clear_tvalid(); |
| once = 1; |
| } |
| } |