blob: ae5a331259b89160b2b0866fcd808d7c5f8da1a1 [file] [log] [blame]
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2015 Intel Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#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;
}
}