122 lines
2.9 KiB
C
122 lines
2.9 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
|
#include <linux/init.h>
|
||
|
|
#include <linux/mm.h>
|
||
|
|
|
||
|
|
#include <asm/mtrr.h>
|
||
|
|
#include <asm/msr.h>
|
||
|
|
|
||
|
|
#include "mtrr.h"
|
||
|
|
|
||
|
|
static struct {
|
||
|
|
unsigned long high;
|
||
|
|
unsigned long low;
|
||
|
|
} centaur_mcr[8];
|
||
|
|
|
||
|
|
static u8 centaur_mcr_reserved;
|
||
|
|
static u8 centaur_mcr_type; /* 0 for winchip, 1 for winchip2 */
|
||
|
|
|
||
|
|
/**
|
||
|
|
* centaur_get_free_region - Get a free MTRR.
|
||
|
|
*
|
||
|
|
* @base: The starting (base) address of the region.
|
||
|
|
* @size: The size (in bytes) of the region.
|
||
|
|
*
|
||
|
|
* Returns: the index of the region on success, else -1 on error.
|
||
|
|
*/
|
||
|
|
static int
|
||
|
|
centaur_get_free_region(unsigned long base, unsigned long size, int replace_reg)
|
||
|
|
{
|
||
|
|
unsigned long lbase, lsize;
|
||
|
|
mtrr_type ltype;
|
||
|
|
int i, max;
|
||
|
|
|
||
|
|
max = num_var_ranges;
|
||
|
|
if (replace_reg >= 0 && replace_reg < max)
|
||
|
|
return replace_reg;
|
||
|
|
|
||
|
|
for (i = 0; i < max; ++i) {
|
||
|
|
if (centaur_mcr_reserved & (1 << i))
|
||
|
|
continue;
|
||
|
|
mtrr_if->get(i, &lbase, &lsize, <ype);
|
||
|
|
if (lsize == 0)
|
||
|
|
return i;
|
||
|
|
}
|
||
|
|
|
||
|
|
return -ENOSPC;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Report boot time MCR setups
|
||
|
|
*/
|
||
|
|
void mtrr_centaur_report_mcr(int mcr, u32 lo, u32 hi)
|
||
|
|
{
|
||
|
|
centaur_mcr[mcr].low = lo;
|
||
|
|
centaur_mcr[mcr].high = hi;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void
|
||
|
|
centaur_get_mcr(unsigned int reg, unsigned long *base,
|
||
|
|
unsigned long *size, mtrr_type * type)
|
||
|
|
{
|
||
|
|
*base = centaur_mcr[reg].high >> PAGE_SHIFT;
|
||
|
|
*size = -(centaur_mcr[reg].low & 0xfffff000) >> PAGE_SHIFT;
|
||
|
|
*type = MTRR_TYPE_WRCOMB; /* write-combining */
|
||
|
|
|
||
|
|
if (centaur_mcr_type == 1 && ((centaur_mcr[reg].low & 31) & 2))
|
||
|
|
*type = MTRR_TYPE_UNCACHABLE;
|
||
|
|
if (centaur_mcr_type == 1 && (centaur_mcr[reg].low & 31) == 25)
|
||
|
|
*type = MTRR_TYPE_WRBACK;
|
||
|
|
if (centaur_mcr_type == 0 && (centaur_mcr[reg].low & 31) == 31)
|
||
|
|
*type = MTRR_TYPE_WRBACK;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void
|
||
|
|
centaur_set_mcr(unsigned int reg, unsigned long base,
|
||
|
|
unsigned long size, mtrr_type type)
|
||
|
|
{
|
||
|
|
unsigned long low, high;
|
||
|
|
|
||
|
|
if (size == 0) {
|
||
|
|
/* Disable */
|
||
|
|
high = low = 0;
|
||
|
|
} else {
|
||
|
|
high = base << PAGE_SHIFT;
|
||
|
|
if (centaur_mcr_type == 0) {
|
||
|
|
/* Only support write-combining... */
|
||
|
|
low = -size << PAGE_SHIFT | 0x1f;
|
||
|
|
} else {
|
||
|
|
if (type == MTRR_TYPE_UNCACHABLE)
|
||
|
|
low = -size << PAGE_SHIFT | 0x02; /* NC */
|
||
|
|
else
|
||
|
|
low = -size << PAGE_SHIFT | 0x09; /* WWO, WC */
|
||
|
|
}
|
||
|
|
}
|
||
|
|
centaur_mcr[reg].high = high;
|
||
|
|
centaur_mcr[reg].low = low;
|
||
|
|
wrmsr(MSR_IDT_MCR0 + reg, low, high);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int
|
||
|
|
centaur_validate_add_page(unsigned long base, unsigned long size, unsigned int type)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* FIXME: Winchip2 supports uncached
|
||
|
|
*/
|
||
|
|
if (type != MTRR_TYPE_WRCOMB &&
|
||
|
|
(centaur_mcr_type == 0 || type != MTRR_TYPE_UNCACHABLE)) {
|
||
|
|
pr_warn("mtrr: only write-combining%s supported\n",
|
||
|
|
centaur_mcr_type ? " and uncacheable are" : " is");
|
||
|
|
return -EINVAL;
|
||
|
|
}
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
const struct mtrr_ops centaur_mtrr_ops = {
|
||
|
|
.vendor = X86_VENDOR_CENTAUR,
|
||
|
|
.set = centaur_set_mcr,
|
||
|
|
.get = centaur_get_mcr,
|
||
|
|
.get_free_region = centaur_get_free_region,
|
||
|
|
.validate_add_page = centaur_validate_add_page,
|
||
|
|
.have_wrcomb = positive_have_wrcomb,
|
||
|
|
};
|