blob: 260a008093026303739f56abb7e113b6eca32cab [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2014 Google, Inc
*
* Memory Type Range Regsters - these are used to tell the CPU whether
* memory is cacheable and if so the cache write mode to use.
*
* These can speed up booting. See the mtrr command.
*
* Reference: Intel Architecture Software Developer's Manual, Volume 3:
* System Programming
*/
/*
* Note that any console output (e.g. debug()) in this file will likely fail
* since the MTRR registers are sometimes in flux.
*/
#include <common.h>
#include <cpu_func.h>
#include <log.h>
#include <sort.h>
#include <asm/cache.h>
#include <asm/global_data.h>
#include <asm/io.h>
#include <asm/mp.h>
#include <asm/msr.h>
#include <asm/mtrr.h>
#include <linux/log2.h>
DECLARE_GLOBAL_DATA_PTR;
/* Prepare to adjust MTRRs */
void mtrr_open(struct mtrr_state *state, bool do_caches)
{
if (!gd->arch.has_mtrr)
return;
if (do_caches) {
state->enable_cache = dcache_status();
if (state->enable_cache)
disable_caches();
}
state->deftype = native_read_msr(MTRR_DEF_TYPE_MSR);
wrmsrl(MTRR_DEF_TYPE_MSR, state->deftype & ~MTRR_DEF_TYPE_EN);
}
/* Clean up after adjusting MTRRs, and enable them */
void mtrr_close(struct mtrr_state *state, bool do_caches)
{
if (!gd->arch.has_mtrr)
return;
wrmsrl(MTRR_DEF_TYPE_MSR, state->deftype | MTRR_DEF_TYPE_EN);
if (do_caches && state->enable_cache)
enable_caches();
}
static void set_var_mtrr(uint reg, uint type, uint64_t start, uint64_t size)
{
u64 mask;
wrmsrl(MTRR_PHYS_BASE_MSR(reg), start | type);
mask = ~(size - 1);
mask &= (1ULL << CONFIG_CPU_ADDR_BITS) - 1;
wrmsrl(MTRR_PHYS_MASK_MSR(reg), mask | MTRR_PHYS_MASK_VALID);
}
void mtrr_read_all(struct mtrr_info *info)
{
int reg_count = mtrr_get_var_count();
int i;
for (i = 0; i < reg_count; i++) {
info->mtrr[i].base = native_read_msr(MTRR_PHYS_BASE_MSR(i));
info->mtrr[i].mask = native_read_msr(MTRR_PHYS_MASK_MSR(i));
}
}
void mtrr_write_all(struct mtrr_info *info)
{
int reg_count = mtrr_get_var_count();
struct mtrr_state state;
int i;
for (i = 0; i < reg_count; i++) {
mtrr_open(&state, true);
wrmsrl(MTRR_PHYS_BASE_MSR(i), info->mtrr[i].base);
wrmsrl(MTRR_PHYS_MASK_MSR(i), info->mtrr[i].mask);
mtrr_close(&state, true);
}
}
static void write_mtrrs(void *arg)
{
struct mtrr_info *info = arg;
mtrr_write_all(info);
}
static void read_mtrrs(void *arg)
{
struct mtrr_info *info = arg;
mtrr_read_all(info);
}
/**
* mtrr_copy_to_aps() - Copy the MTRRs from the boot CPU to other CPUs
*
* @return 0 on success, -ve on failure
*/
static int mtrr_copy_to_aps(void)
{
struct mtrr_info info;
int ret;
ret = mp_run_on_cpus(MP_SELECT_BSP, read_mtrrs, &info);
if (ret == -ENXIO)
return 0;
else if (ret)
return log_msg_ret("bsp", ret);
ret = mp_run_on_cpus(MP_SELECT_APS, write_mtrrs, &info);
if (ret)
return log_msg_ret("bsp", ret);
return 0;
}
static int h_comp_mtrr(const void *p1, const void *p2)
{
const struct mtrr_request *req1 = p1;
const struct mtrr_request *req2 = p2;
s64 diff = req1->start - req2->start;
return diff < 0 ? -1 : diff > 0 ? 1 : 0;
}
int mtrr_commit(bool do_caches)
{
struct mtrr_request *req = gd->arch.mtrr_req;
struct mtrr_state state;
int ret;
int i;
debug("%s: enabled=%d, count=%d\n", __func__, gd->arch.has_mtrr,
gd->arch.mtrr_req_count);
if (!gd->arch.has_mtrr)
return -ENOSYS;
debug("open\n");
mtrr_open(&state, do_caches);
debug("open done\n");
qsort(req, gd->arch.mtrr_req_count, sizeof(*req), h_comp_mtrr);
for (i = 0; i < gd->arch.mtrr_req_count; i++, req++)
mtrr_set_next_var(req->type, req->start, req->size);
debug("close\n");
mtrr_close(&state, do_caches);
debug("mtrr done\n");
if (gd->flags & GD_FLG_RELOC) {
ret = mtrr_copy_to_aps();
if (ret)
return log_msg_ret("copy", ret);
}
return 0;
}
int mtrr_add_request(int type, uint64_t start, uint64_t size)
{
struct mtrr_request *req;
uint64_t mask;
debug("%s: count=%d\n", __func__, gd->arch.mtrr_req_count);
if (!gd->arch.has_mtrr)
return -ENOSYS;
if (!is_power_of_2(size))
return -EINVAL;
if (gd->arch.mtrr_req_count == MAX_MTRR_REQUESTS)
return -ENOSPC;
req = &gd->arch.mtrr_req[gd->arch.mtrr_req_count++];
req->type = type;
req->start = start;
req->size = size;
debug("%d: type=%d, %08llx %08llx\n", gd->arch.mtrr_req_count - 1,
req->type, req->start, req->size);
mask = ~(req->size - 1);
mask &= (1ULL << CONFIG_CPU_ADDR_BITS) - 1;
mask |= MTRR_PHYS_MASK_VALID;
debug(" %016llx %016llx\n", req->start | req->type, mask);
return 0;
}
int mtrr_get_var_count(void)
{
return msr_read(MSR_MTRR_CAP_MSR).lo & MSR_MTRR_CAP_VCNT;
}
static int get_free_var_mtrr(void)
{
struct msr_t maskm;
int vcnt;
int i;
vcnt = mtrr_get_var_count();
/* Identify the first var mtrr which is not valid */
for (i = 0; i < vcnt; i++) {
maskm = msr_read(MTRR_PHYS_MASK_MSR(i));
if ((maskm.lo & MTRR_PHYS_MASK_VALID) == 0)
return i;
}
/* No free var mtrr */
return -ENOSPC;
}
int mtrr_set_next_var(uint type, uint64_t start, uint64_t size)
{
int mtrr;
if (!is_power_of_2(size))
return -EINVAL;
mtrr = get_free_var_mtrr();
if (mtrr < 0)
return mtrr;
set_var_mtrr(mtrr, type, start, size);
debug("MTRR %x: start=%x, size=%x\n", mtrr, (uint)start, (uint)size);
return 0;
}
/** enum mtrr_opcode - supported operations for mtrr_do_oper() */
enum mtrr_opcode {
MTRR_OP_SET,
MTRR_OP_SET_VALID,
};
/**
* struct mtrr_oper - An MTRR operation to perform on a CPU
*
* @opcode: Indicates operation to perform
* @reg: MTRR reg number to select (0-7, -1 = all)
* @valid: Valid value to write for MTRR_OP_SET_VALID
* @base: Base value to write for MTRR_OP_SET
* @mask: Mask value to write for MTRR_OP_SET
*/
struct mtrr_oper {
enum mtrr_opcode opcode;
int reg;
bool valid;
u64 base;
u64 mask;
};
static void mtrr_do_oper(void *arg)
{
struct mtrr_oper *oper = arg;
u64 mask;
switch (oper->opcode) {
case MTRR_OP_SET_VALID:
mask = native_read_msr(MTRR_PHYS_MASK_MSR(oper->reg));
if (oper->valid)
mask |= MTRR_PHYS_MASK_VALID;
else
mask &= ~MTRR_PHYS_MASK_VALID;
wrmsrl(MTRR_PHYS_MASK_MSR(oper->reg), mask);
break;
case MTRR_OP_SET:
wrmsrl(MTRR_PHYS_BASE_MSR(oper->reg), oper->base);
wrmsrl(MTRR_PHYS_MASK_MSR(oper->reg), oper->mask);
break;
}
}
static int mtrr_start_op(int cpu_select, struct mtrr_oper *oper)
{
struct mtrr_state state;
int ret;
mtrr_open(&state, true);
ret = mp_run_on_cpus(cpu_select, mtrr_do_oper, oper);
mtrr_close(&state, true);
if (ret)
return log_msg_ret("run", ret);
return 0;
}
int mtrr_set_valid(int cpu_select, int reg, bool valid)
{
struct mtrr_oper oper;
oper.opcode = MTRR_OP_SET_VALID;
oper.reg = reg;
oper.valid = valid;
return mtrr_start_op(cpu_select, &oper);
}
int mtrr_set(int cpu_select, int reg, u64 base, u64 mask)
{
struct mtrr_oper oper;
oper.opcode = MTRR_OP_SET;
oper.reg = reg;
oper.base = base;
oper.mask = mask;
return mtrr_start_op(cpu_select, &oper);
}