diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mtrr')
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/Makefile | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/amd.c | 119 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/centaur.c | 112 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/cleanup.c | 980 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/cyrix.c | 244 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/generic.c | 1070 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/if.c | 425 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/legacy.c | 90 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/mtrr.c | 640 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/mtrr.h | 94 |
10 files changed, 3778 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/Makefile b/arch/x86/kernel/cpu/mtrr/Makefile new file mode 100644 index 0000000000..aee4bc5ad4 --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0-only +obj-y := mtrr.o if.o generic.o cleanup.o +obj-$(CONFIG_X86_32) += amd.o cyrix.o centaur.o legacy.o + diff --git a/arch/x86/kernel/cpu/mtrr/amd.c b/arch/x86/kernel/cpu/mtrr/amd.c new file mode 100644 index 0000000000..ef3e8e42b7 --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/amd.c @@ -0,0 +1,119 @@ +// 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 void +amd_get_mtrr(unsigned int reg, unsigned long *base, + unsigned long *size, mtrr_type *type) +{ + unsigned long low, high; + + rdmsr(MSR_K6_UWCCR, low, high); + /* Upper dword is region 1, lower is region 0 */ + if (reg == 1) + low = high; + /* The base masks off on the right alignment */ + *base = (low & 0xFFFE0000) >> PAGE_SHIFT; + *type = 0; + if (low & 1) + *type = MTRR_TYPE_UNCACHABLE; + if (low & 2) + *type = MTRR_TYPE_WRCOMB; + if (!(low & 3)) { + *size = 0; + return; + } + /* + * This needs a little explaining. The size is stored as an + * inverted mask of bits of 128K granularity 15 bits long offset + * 2 bits. + * + * So to get a size we do invert the mask and add 1 to the lowest + * mask bit (4 as its 2 bits in). This gives us a size we then shift + * to turn into 128K blocks. + * + * eg 111 1111 1111 1100 is 512K + * + * invert 000 0000 0000 0011 + * +1 000 0000 0000 0100 + * *128K ... + */ + low = (~low) & 0x1FFFC; + *size = (low + 4) << (15 - PAGE_SHIFT); +} + +/** + * amd_set_mtrr - Set variable MTRR register on the local CPU. + * + * @reg The register to set. + * @base The base address of the region. + * @size The size of the region. If this is 0 the region is disabled. + * @type The type of the region. + * + * Returns nothing. + */ +static void +amd_set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type type) +{ + u32 regs[2]; + + /* + * Low is MTRR0, High MTRR 1 + */ + rdmsr(MSR_K6_UWCCR, regs[0], regs[1]); + /* + * Blank to disable + */ + if (size == 0) { + regs[reg] = 0; + } else { + /* + * Set the register to the base, the type (off by one) and an + * inverted bitmask of the size The size is the only odd + * bit. We are fed say 512K We invert this and we get 111 1111 + * 1111 1011 but if you subtract one and invert you get the + * desired 111 1111 1111 1100 mask + * + * But ~(x - 1) == ~x + 1 == -x. Two's complement rocks! + */ + regs[reg] = (-size >> (15 - PAGE_SHIFT) & 0x0001FFFC) + | (base << PAGE_SHIFT) | (type + 1); + } + + /* + * The writeback rule is quite specific. See the manual. Its + * disable local interrupts, write back the cache, set the mtrr + */ + wbinvd(); + wrmsr(MSR_K6_UWCCR, regs[0], regs[1]); +} + +static int +amd_validate_add_page(unsigned long base, unsigned long size, unsigned int type) +{ + /* + * Apply the K6 block alignment and size rules + * In order + * o Uncached or gathering only + * o 128K or bigger block + * o Power of 2 block + * o base suitably aligned to the power + */ + if (type > MTRR_TYPE_WRCOMB || size < (1 << (17 - PAGE_SHIFT)) + || (size & ~(size - 1)) - size || (base & (size - 1))) + return -EINVAL; + return 0; +} + +const struct mtrr_ops amd_mtrr_ops = { + .var_regs = 2, + .set = amd_set_mtrr, + .get = amd_get_mtrr, + .get_free_region = generic_get_free_region, + .validate_add_page = amd_validate_add_page, + .have_wrcomb = positive_have_wrcomb, +}; diff --git a/arch/x86/kernel/cpu/mtrr/centaur.c b/arch/x86/kernel/cpu/mtrr/centaur.c new file mode 100644 index 0000000000..6f6c3ae929 --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/centaur.c @@ -0,0 +1,112 @@ +// 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; +} + +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 = { + .var_regs = 8, + .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, +}; diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c b/arch/x86/kernel/cpu/mtrr/cleanup.c new file mode 100644 index 0000000000..18cf79d6e2 --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/cleanup.c @@ -0,0 +1,980 @@ +/* + * MTRR (Memory Type Range Register) cleanup + * + * Copyright (C) 2009 Yinghai Lu + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Library General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public + * License along with this library; if not, write to the Free + * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ +#include <linux/init.h> +#include <linux/pci.h> +#include <linux/smp.h> +#include <linux/cpu.h> +#include <linux/mutex.h> +#include <linux/uaccess.h> +#include <linux/kvm_para.h> +#include <linux/range.h> + +#include <asm/processor.h> +#include <asm/e820/api.h> +#include <asm/mtrr.h> +#include <asm/msr.h> + +#include "mtrr.h" + +struct var_mtrr_range_state { + unsigned long base_pfn; + unsigned long size_pfn; + mtrr_type type; +}; + +struct var_mtrr_state { + unsigned long range_startk; + unsigned long range_sizek; + unsigned long chunk_sizek; + unsigned long gran_sizek; + unsigned int reg; +}; + +/* Should be related to MTRR_VAR_RANGES nums */ +#define RANGE_NUM 256 + +static struct range __initdata range[RANGE_NUM]; +static int __initdata nr_range; + +static struct var_mtrr_range_state __initdata range_state[RANGE_NUM]; + +#define BIOS_BUG_MSG \ + "WARNING: BIOS bug: VAR MTRR %d contains strange UC entry under 1M, check with your system vendor!\n" + +static int __init +x86_get_mtrr_mem_range(struct range *range, int nr_range, + unsigned long extra_remove_base, + unsigned long extra_remove_size) +{ + unsigned long base, size; + mtrr_type type; + int i; + + for (i = 0; i < num_var_ranges; i++) { + type = range_state[i].type; + if (type != MTRR_TYPE_WRBACK) + continue; + base = range_state[i].base_pfn; + size = range_state[i].size_pfn; + nr_range = add_range_with_merge(range, RANGE_NUM, nr_range, + base, base + size); + } + + Dprintk("After WB checking\n"); + for (i = 0; i < nr_range; i++) + Dprintk("MTRR MAP PFN: %016llx - %016llx\n", + range[i].start, range[i].end); + + /* Take out UC ranges: */ + for (i = 0; i < num_var_ranges; i++) { + type = range_state[i].type; + if (type != MTRR_TYPE_UNCACHABLE && + type != MTRR_TYPE_WRPROT) + continue; + size = range_state[i].size_pfn; + if (!size) + continue; + base = range_state[i].base_pfn; + if (base < (1<<(20-PAGE_SHIFT)) && mtrr_state.have_fixed && + (mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED) && + (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) { + /* Var MTRR contains UC entry below 1M? Skip it: */ + pr_warn(BIOS_BUG_MSG, i); + if (base + size <= (1<<(20-PAGE_SHIFT))) + continue; + size -= (1<<(20-PAGE_SHIFT)) - base; + base = 1<<(20-PAGE_SHIFT); + } + subtract_range(range, RANGE_NUM, base, base + size); + } + if (extra_remove_size) + subtract_range(range, RANGE_NUM, extra_remove_base, + extra_remove_base + extra_remove_size); + + Dprintk("After UC checking\n"); + for (i = 0; i < RANGE_NUM; i++) { + if (!range[i].end) + continue; + + Dprintk("MTRR MAP PFN: %016llx - %016llx\n", + range[i].start, range[i].end); + } + + /* sort the ranges */ + nr_range = clean_sort_range(range, RANGE_NUM); + + Dprintk("After sorting\n"); + for (i = 0; i < nr_range; i++) + Dprintk("MTRR MAP PFN: %016llx - %016llx\n", + range[i].start, range[i].end); + + return nr_range; +} + +#ifdef CONFIG_MTRR_SANITIZER + +static unsigned long __init sum_ranges(struct range *range, int nr_range) +{ + unsigned long sum = 0; + int i; + + for (i = 0; i < nr_range; i++) + sum += range[i].end - range[i].start; + + return sum; +} + +static int enable_mtrr_cleanup __initdata = + CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT; + +static int __init disable_mtrr_cleanup_setup(char *str) +{ + enable_mtrr_cleanup = 0; + return 0; +} +early_param("disable_mtrr_cleanup", disable_mtrr_cleanup_setup); + +static int __init enable_mtrr_cleanup_setup(char *str) +{ + enable_mtrr_cleanup = 1; + return 0; +} +early_param("enable_mtrr_cleanup", enable_mtrr_cleanup_setup); + +static void __init +set_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek, + unsigned char type) +{ + u32 base_lo, base_hi, mask_lo, mask_hi; + u64 base, mask; + + if (!sizek) { + fill_mtrr_var_range(reg, 0, 0, 0, 0); + return; + } + + mask = (1ULL << boot_cpu_data.x86_phys_bits) - 1; + mask &= ~((((u64)sizek) << 10) - 1); + + base = ((u64)basek) << 10; + + base |= type; + mask |= 0x800; + + base_lo = base & ((1ULL<<32) - 1); + base_hi = base >> 32; + + mask_lo = mask & ((1ULL<<32) - 1); + mask_hi = mask >> 32; + + fill_mtrr_var_range(reg, base_lo, base_hi, mask_lo, mask_hi); +} + +static void __init +save_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek, + unsigned char type) +{ + range_state[reg].base_pfn = basek >> (PAGE_SHIFT - 10); + range_state[reg].size_pfn = sizek >> (PAGE_SHIFT - 10); + range_state[reg].type = type; +} + +static void __init set_var_mtrr_all(void) +{ + unsigned long basek, sizek; + unsigned char type; + unsigned int reg; + + for (reg = 0; reg < num_var_ranges; reg++) { + basek = range_state[reg].base_pfn << (PAGE_SHIFT - 10); + sizek = range_state[reg].size_pfn << (PAGE_SHIFT - 10); + type = range_state[reg].type; + + set_var_mtrr(reg, basek, sizek, type); + } +} + +static unsigned long to_size_factor(unsigned long sizek, char *factorp) +{ + unsigned long base = sizek; + char factor; + + if (base & ((1<<10) - 1)) { + /* Not MB-aligned: */ + factor = 'K'; + } else if (base & ((1<<20) - 1)) { + factor = 'M'; + base >>= 10; + } else { + factor = 'G'; + base >>= 20; + } + + *factorp = factor; + + return base; +} + +static unsigned int __init +range_to_mtrr(unsigned int reg, unsigned long range_startk, + unsigned long range_sizek, unsigned char type) +{ + if (!range_sizek || (reg >= num_var_ranges)) + return reg; + + while (range_sizek) { + unsigned long max_align, align; + unsigned long sizek; + + /* Compute the maximum size with which we can make a range: */ + if (range_startk) + max_align = __ffs(range_startk); + else + max_align = BITS_PER_LONG - 1; + + align = __fls(range_sizek); + if (align > max_align) + align = max_align; + + sizek = 1UL << align; + if (mtrr_debug) { + char start_factor = 'K', size_factor = 'K'; + unsigned long start_base, size_base; + + start_base = to_size_factor(range_startk, &start_factor); + size_base = to_size_factor(sizek, &size_factor); + + Dprintk("Setting variable MTRR %d, " + "base: %ld%cB, range: %ld%cB, type %s\n", + reg, start_base, start_factor, + size_base, size_factor, + (type == MTRR_TYPE_UNCACHABLE) ? "UC" : + ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other") + ); + } + save_var_mtrr(reg++, range_startk, sizek, type); + range_startk += sizek; + range_sizek -= sizek; + if (reg >= num_var_ranges) + break; + } + return reg; +} + +static unsigned __init +range_to_mtrr_with_hole(struct var_mtrr_state *state, unsigned long basek, + unsigned long sizek) +{ + unsigned long hole_basek, hole_sizek; + unsigned long second_sizek; + unsigned long range0_basek, range0_sizek; + unsigned long range_basek, range_sizek; + unsigned long chunk_sizek; + unsigned long gran_sizek; + + hole_basek = 0; + hole_sizek = 0; + second_sizek = 0; + chunk_sizek = state->chunk_sizek; + gran_sizek = state->gran_sizek; + + /* Align with gran size, prevent small block used up MTRRs: */ + range_basek = ALIGN(state->range_startk, gran_sizek); + if ((range_basek > basek) && basek) + return second_sizek; + + state->range_sizek -= (range_basek - state->range_startk); + range_sizek = ALIGN(state->range_sizek, gran_sizek); + + while (range_sizek > state->range_sizek) { + range_sizek -= gran_sizek; + if (!range_sizek) + return 0; + } + state->range_sizek = range_sizek; + + /* Try to append some small hole: */ + range0_basek = state->range_startk; + range0_sizek = ALIGN(state->range_sizek, chunk_sizek); + + /* No increase: */ + if (range0_sizek == state->range_sizek) { + Dprintk("rangeX: %016lx - %016lx\n", + range0_basek<<10, + (range0_basek + state->range_sizek)<<10); + state->reg = range_to_mtrr(state->reg, range0_basek, + state->range_sizek, MTRR_TYPE_WRBACK); + return 0; + } + + /* Only cut back when it is not the last: */ + if (sizek) { + while (range0_basek + range0_sizek > (basek + sizek)) { + if (range0_sizek >= chunk_sizek) + range0_sizek -= chunk_sizek; + else + range0_sizek = 0; + + if (!range0_sizek) + break; + } + } + +second_try: + range_basek = range0_basek + range0_sizek; + + /* One hole in the middle: */ + if (range_basek > basek && range_basek <= (basek + sizek)) + second_sizek = range_basek - basek; + + if (range0_sizek > state->range_sizek) { + + /* One hole in middle or at the end: */ + hole_sizek = range0_sizek - state->range_sizek - second_sizek; + + /* Hole size should be less than half of range0 size: */ + if (hole_sizek >= (range0_sizek >> 1) && + range0_sizek >= chunk_sizek) { + range0_sizek -= chunk_sizek; + second_sizek = 0; + hole_sizek = 0; + + goto second_try; + } + } + + if (range0_sizek) { + Dprintk("range0: %016lx - %016lx\n", + range0_basek<<10, + (range0_basek + range0_sizek)<<10); + state->reg = range_to_mtrr(state->reg, range0_basek, + range0_sizek, MTRR_TYPE_WRBACK); + } + + if (range0_sizek < state->range_sizek) { + /* Need to handle left over range: */ + range_sizek = state->range_sizek - range0_sizek; + + Dprintk("range: %016lx - %016lx\n", + range_basek<<10, + (range_basek + range_sizek)<<10); + + state->reg = range_to_mtrr(state->reg, range_basek, + range_sizek, MTRR_TYPE_WRBACK); + } + + if (hole_sizek) { + hole_basek = range_basek - hole_sizek - second_sizek; + Dprintk("hole: %016lx - %016lx\n", + hole_basek<<10, + (hole_basek + hole_sizek)<<10); + state->reg = range_to_mtrr(state->reg, hole_basek, + hole_sizek, MTRR_TYPE_UNCACHABLE); + } + + return second_sizek; +} + +static void __init +set_var_mtrr_range(struct var_mtrr_state *state, unsigned long base_pfn, + unsigned long size_pfn) +{ + unsigned long basek, sizek; + unsigned long second_sizek = 0; + + if (state->reg >= num_var_ranges) + return; + + basek = base_pfn << (PAGE_SHIFT - 10); + sizek = size_pfn << (PAGE_SHIFT - 10); + + /* See if I can merge with the last range: */ + if ((basek <= 1024) || + (state->range_startk + state->range_sizek == basek)) { + unsigned long endk = basek + sizek; + state->range_sizek = endk - state->range_startk; + return; + } + /* Write the range mtrrs: */ + if (state->range_sizek != 0) + second_sizek = range_to_mtrr_with_hole(state, basek, sizek); + + /* Allocate an msr: */ + state->range_startk = basek + second_sizek; + state->range_sizek = sizek - second_sizek; +} + +/* Minimum size of mtrr block that can take hole: */ +static u64 mtrr_chunk_size __initdata = (256ULL<<20); + +static int __init parse_mtrr_chunk_size_opt(char *p) +{ + if (!p) + return -EINVAL; + mtrr_chunk_size = memparse(p, &p); + return 0; +} +early_param("mtrr_chunk_size", parse_mtrr_chunk_size_opt); + +/* Granularity of mtrr of block: */ +static u64 mtrr_gran_size __initdata; + +static int __init parse_mtrr_gran_size_opt(char *p) +{ + if (!p) + return -EINVAL; + mtrr_gran_size = memparse(p, &p); + return 0; +} +early_param("mtrr_gran_size", parse_mtrr_gran_size_opt); + +static unsigned long nr_mtrr_spare_reg __initdata = + CONFIG_MTRR_SANITIZER_SPARE_REG_NR_DEFAULT; + +static int __init parse_mtrr_spare_reg(char *arg) +{ + if (arg) + nr_mtrr_spare_reg = simple_strtoul(arg, NULL, 0); + return 0; +} +early_param("mtrr_spare_reg_nr", parse_mtrr_spare_reg); + +static int __init +x86_setup_var_mtrrs(struct range *range, int nr_range, + u64 chunk_size, u64 gran_size) +{ + struct var_mtrr_state var_state; + int num_reg; + int i; + + var_state.range_startk = 0; + var_state.range_sizek = 0; + var_state.reg = 0; + var_state.chunk_sizek = chunk_size >> 10; + var_state.gran_sizek = gran_size >> 10; + + memset(range_state, 0, sizeof(range_state)); + + /* Write the range: */ + for (i = 0; i < nr_range; i++) { + set_var_mtrr_range(&var_state, range[i].start, + range[i].end - range[i].start); + } + + /* Write the last range: */ + if (var_state.range_sizek != 0) + range_to_mtrr_with_hole(&var_state, 0, 0); + + num_reg = var_state.reg; + /* Clear out the extra MTRR's: */ + while (var_state.reg < num_var_ranges) { + save_var_mtrr(var_state.reg, 0, 0, 0); + var_state.reg++; + } + + return num_reg; +} + +struct mtrr_cleanup_result { + unsigned long gran_sizek; + unsigned long chunk_sizek; + unsigned long lose_cover_sizek; + unsigned int num_reg; + int bad; +}; + +/* + * gran_size: 64K, 128K, 256K, 512K, 1M, 2M, ..., 2G + * chunk size: gran_size, ..., 2G + * so we need (1+16)*8 + */ +#define NUM_RESULT 136 +#define PSHIFT (PAGE_SHIFT - 10) + +static struct mtrr_cleanup_result __initdata result[NUM_RESULT]; +static unsigned long __initdata min_loss_pfn[RANGE_NUM]; + +static void __init print_out_mtrr_range_state(void) +{ + char start_factor = 'K', size_factor = 'K'; + unsigned long start_base, size_base; + mtrr_type type; + int i; + + for (i = 0; i < num_var_ranges; i++) { + + size_base = range_state[i].size_pfn << (PAGE_SHIFT - 10); + if (!size_base) + continue; + + size_base = to_size_factor(size_base, &size_factor); + start_base = range_state[i].base_pfn << (PAGE_SHIFT - 10); + start_base = to_size_factor(start_base, &start_factor); + type = range_state[i].type; + + Dprintk("reg %d, base: %ld%cB, range: %ld%cB, type %s\n", + i, start_base, start_factor, + size_base, size_factor, + (type == MTRR_TYPE_UNCACHABLE) ? "UC" : + ((type == MTRR_TYPE_WRPROT) ? "WP" : + ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other")) + ); + } +} + +static int __init mtrr_need_cleanup(void) +{ + int i; + mtrr_type type; + unsigned long size; + /* Extra one for all 0: */ + int num[MTRR_NUM_TYPES + 1]; + + /* Check entries number: */ + memset(num, 0, sizeof(num)); + for (i = 0; i < num_var_ranges; i++) { + type = range_state[i].type; + size = range_state[i].size_pfn; + if (type >= MTRR_NUM_TYPES) + continue; + if (!size) + type = MTRR_NUM_TYPES; + num[type]++; + } + + /* Check if we got UC entries: */ + if (!num[MTRR_TYPE_UNCACHABLE]) + return 0; + + /* Check if we only had WB and UC */ + if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] != + num_var_ranges - num[MTRR_NUM_TYPES]) + return 0; + + return 1; +} + +static unsigned long __initdata range_sums; + +static void __init +mtrr_calc_range_state(u64 chunk_size, u64 gran_size, + unsigned long x_remove_base, + unsigned long x_remove_size, int i) +{ + /* + * range_new should really be an automatic variable, but + * putting 4096 bytes on the stack is frowned upon, to put it + * mildly. It is safe to make it a static __initdata variable, + * since mtrr_calc_range_state is only called during init and + * there's no way it will call itself recursively. + */ + static struct range range_new[RANGE_NUM] __initdata; + unsigned long range_sums_new; + int nr_range_new; + int num_reg; + + /* Convert ranges to var ranges state: */ + num_reg = x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size); + + /* We got new setting in range_state, check it: */ + memset(range_new, 0, sizeof(range_new)); + nr_range_new = x86_get_mtrr_mem_range(range_new, 0, + x_remove_base, x_remove_size); + range_sums_new = sum_ranges(range_new, nr_range_new); + + result[i].chunk_sizek = chunk_size >> 10; + result[i].gran_sizek = gran_size >> 10; + result[i].num_reg = num_reg; + + if (range_sums < range_sums_new) { + result[i].lose_cover_sizek = (range_sums_new - range_sums) << PSHIFT; + result[i].bad = 1; + } else { + result[i].lose_cover_sizek = (range_sums - range_sums_new) << PSHIFT; + } + + /* Double check it: */ + if (!result[i].bad && !result[i].lose_cover_sizek) { + if (nr_range_new != nr_range || memcmp(range, range_new, sizeof(range))) + result[i].bad = 1; + } + + if (!result[i].bad && (range_sums - range_sums_new < min_loss_pfn[num_reg])) + min_loss_pfn[num_reg] = range_sums - range_sums_new; +} + +static void __init mtrr_print_out_one_result(int i) +{ + unsigned long gran_base, chunk_base, lose_base; + char gran_factor, chunk_factor, lose_factor; + + gran_base = to_size_factor(result[i].gran_sizek, &gran_factor); + chunk_base = to_size_factor(result[i].chunk_sizek, &chunk_factor); + lose_base = to_size_factor(result[i].lose_cover_sizek, &lose_factor); + + pr_info("%sgran_size: %ld%c \tchunk_size: %ld%c \t", + result[i].bad ? "*BAD*" : " ", + gran_base, gran_factor, chunk_base, chunk_factor); + pr_cont("num_reg: %d \tlose cover RAM: %s%ld%c\n", + result[i].num_reg, result[i].bad ? "-" : "", + lose_base, lose_factor); +} + +static int __init mtrr_search_optimal_index(void) +{ + int num_reg_good; + int index_good; + int i; + + if (nr_mtrr_spare_reg >= num_var_ranges) + nr_mtrr_spare_reg = num_var_ranges - 1; + + num_reg_good = -1; + for (i = num_var_ranges - nr_mtrr_spare_reg; i > 0; i--) { + if (!min_loss_pfn[i]) + num_reg_good = i; + } + + index_good = -1; + if (num_reg_good != -1) { + for (i = 0; i < NUM_RESULT; i++) { + if (!result[i].bad && + result[i].num_reg == num_reg_good && + !result[i].lose_cover_sizek) { + index_good = i; + break; + } + } + } + + return index_good; +} + +int __init mtrr_cleanup(void) +{ + unsigned long x_remove_base, x_remove_size; + unsigned long base, size, def, dummy; + u64 chunk_size, gran_size; + mtrr_type type; + int index_good; + int i; + + if (!mtrr_enabled()) + return 0; + + if (!cpu_feature_enabled(X86_FEATURE_MTRR) || enable_mtrr_cleanup < 1) + return 0; + + rdmsr(MSR_MTRRdefType, def, dummy); + def &= 0xff; + if (def != MTRR_TYPE_UNCACHABLE) + return 0; + + /* Get it and store it aside: */ + memset(range_state, 0, sizeof(range_state)); + for (i = 0; i < num_var_ranges; i++) { + mtrr_if->get(i, &base, &size, &type); + range_state[i].base_pfn = base; + range_state[i].size_pfn = size; + range_state[i].type = type; + } + + /* Check if we need handle it and can handle it: */ + if (!mtrr_need_cleanup()) + return 0; + + /* Print original var MTRRs at first, for debugging: */ + Dprintk("original variable MTRRs\n"); + print_out_mtrr_range_state(); + + memset(range, 0, sizeof(range)); + x_remove_size = 0; + x_remove_base = 1 << (32 - PAGE_SHIFT); + if (mtrr_tom2) + x_remove_size = (mtrr_tom2 >> PAGE_SHIFT) - x_remove_base; + + /* + * [0, 1M) should always be covered by var mtrr with WB + * and fixed mtrrs should take effect before var mtrr for it: + */ + nr_range = add_range_with_merge(range, RANGE_NUM, 0, 0, + 1ULL<<(20 - PAGE_SHIFT)); + /* add from var mtrr at last */ + nr_range = x86_get_mtrr_mem_range(range, nr_range, + x_remove_base, x_remove_size); + + range_sums = sum_ranges(range, nr_range); + pr_info("total RAM covered: %ldM\n", + range_sums >> (20 - PAGE_SHIFT)); + + if (mtrr_chunk_size && mtrr_gran_size) { + i = 0; + mtrr_calc_range_state(mtrr_chunk_size, mtrr_gran_size, + x_remove_base, x_remove_size, i); + + mtrr_print_out_one_result(i); + + if (!result[i].bad) { + set_var_mtrr_all(); + Dprintk("New variable MTRRs\n"); + print_out_mtrr_range_state(); + return 1; + } + pr_info("invalid mtrr_gran_size or mtrr_chunk_size, will find optimal one\n"); + } + + i = 0; + memset(min_loss_pfn, 0xff, sizeof(min_loss_pfn)); + memset(result, 0, sizeof(result)); + for (gran_size = (1ULL<<16); gran_size < (1ULL<<32); gran_size <<= 1) { + + for (chunk_size = gran_size; chunk_size < (1ULL<<32); + chunk_size <<= 1) { + + if (i >= NUM_RESULT) + continue; + + mtrr_calc_range_state(chunk_size, gran_size, + x_remove_base, x_remove_size, i); + if (mtrr_debug) { + mtrr_print_out_one_result(i); + pr_info("\n"); + } + + i++; + } + } + + /* Try to find the optimal index: */ + index_good = mtrr_search_optimal_index(); + + if (index_good != -1) { + pr_info("Found optimal setting for mtrr clean up\n"); + i = index_good; + mtrr_print_out_one_result(i); + + /* Convert ranges to var ranges state: */ + chunk_size = result[i].chunk_sizek; + chunk_size <<= 10; + gran_size = result[i].gran_sizek; + gran_size <<= 10; + x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size); + set_var_mtrr_all(); + Dprintk("New variable MTRRs\n"); + print_out_mtrr_range_state(); + return 1; + } else { + /* print out all */ + for (i = 0; i < NUM_RESULT; i++) + mtrr_print_out_one_result(i); + } + + pr_info("mtrr_cleanup: can not find optimal value\n"); + pr_info("please specify mtrr_gran_size/mtrr_chunk_size\n"); + + return 0; +} +#else +int __init mtrr_cleanup(void) +{ + return 0; +} +#endif + +static int disable_mtrr_trim; + +static int __init disable_mtrr_trim_setup(char *str) +{ + disable_mtrr_trim = 1; + return 0; +} +early_param("disable_mtrr_trim", disable_mtrr_trim_setup); + +/* + * Newer AMD K8s and later CPUs have a special magic MSR way to force WB + * for memory >4GB. Check for that here. + * Note this won't check if the MTRRs < 4GB where the magic bit doesn't + * apply to are wrong, but so far we don't know of any such case in the wild. + */ +#define Tom2Enabled (1U << 21) +#define Tom2ForceMemTypeWB (1U << 22) + +int __init amd_special_default_mtrr(void) +{ + u32 l, h; + + if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD && + boot_cpu_data.x86_vendor != X86_VENDOR_HYGON) + return 0; + if (boot_cpu_data.x86 < 0xf) + return 0; + /* In case some hypervisor doesn't pass SYSCFG through: */ + if (rdmsr_safe(MSR_AMD64_SYSCFG, &l, &h) < 0) + return 0; + /* + * Memory between 4GB and top of mem is forced WB by this magic bit. + * Reserved before K8RevF, but should be zero there. + */ + if ((l & (Tom2Enabled | Tom2ForceMemTypeWB)) == + (Tom2Enabled | Tom2ForceMemTypeWB)) + return 1; + return 0; +} + +static u64 __init +real_trim_memory(unsigned long start_pfn, unsigned long limit_pfn) +{ + u64 trim_start, trim_size; + + trim_start = start_pfn; + trim_start <<= PAGE_SHIFT; + + trim_size = limit_pfn; + trim_size <<= PAGE_SHIFT; + trim_size -= trim_start; + + return e820__range_update(trim_start, trim_size, E820_TYPE_RAM, E820_TYPE_RESERVED); +} + +/** + * mtrr_trim_uncached_memory - trim RAM not covered by MTRRs + * @end_pfn: ending page frame number + * + * Some buggy BIOSes don't setup the MTRRs properly for systems with certain + * memory configurations. This routine checks that the highest MTRR matches + * the end of memory, to make sure the MTRRs having a write back type cover + * all of the memory the kernel is intending to use. If not, it'll trim any + * memory off the end by adjusting end_pfn, removing it from the kernel's + * allocation pools, warning the user with an obnoxious message. + */ +int __init mtrr_trim_uncached_memory(unsigned long end_pfn) +{ + unsigned long i, base, size, highest_pfn = 0, def, dummy; + mtrr_type type; + u64 total_trim_size; + /* extra one for all 0 */ + int num[MTRR_NUM_TYPES + 1]; + + if (!mtrr_enabled()) + return 0; + + /* + * Make sure we only trim uncachable memory on machines that + * support the Intel MTRR architecture: + */ + if (!cpu_feature_enabled(X86_FEATURE_MTRR) || disable_mtrr_trim) + return 0; + + rdmsr(MSR_MTRRdefType, def, dummy); + def &= MTRR_DEF_TYPE_TYPE; + if (def != MTRR_TYPE_UNCACHABLE) + return 0; + + /* Get it and store it aside: */ + memset(range_state, 0, sizeof(range_state)); + for (i = 0; i < num_var_ranges; i++) { + mtrr_if->get(i, &base, &size, &type); + range_state[i].base_pfn = base; + range_state[i].size_pfn = size; + range_state[i].type = type; + } + + /* Find highest cached pfn: */ + for (i = 0; i < num_var_ranges; i++) { + type = range_state[i].type; + if (type != MTRR_TYPE_WRBACK) + continue; + base = range_state[i].base_pfn; + size = range_state[i].size_pfn; + if (highest_pfn < base + size) + highest_pfn = base + size; + } + + /* kvm/qemu doesn't have mtrr set right, don't trim them all: */ + if (!highest_pfn) { + pr_info("CPU MTRRs all blank - virtualized system.\n"); + return 0; + } + + /* Check entries number: */ + memset(num, 0, sizeof(num)); + for (i = 0; i < num_var_ranges; i++) { + type = range_state[i].type; + if (type >= MTRR_NUM_TYPES) + continue; + size = range_state[i].size_pfn; + if (!size) + type = MTRR_NUM_TYPES; + num[type]++; + } + + /* No entry for WB? */ + if (!num[MTRR_TYPE_WRBACK]) + return 0; + + /* Check if we only had WB and UC: */ + if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] != + num_var_ranges - num[MTRR_NUM_TYPES]) + return 0; + + memset(range, 0, sizeof(range)); + nr_range = 0; + if (mtrr_tom2) { + range[nr_range].start = (1ULL<<(32 - PAGE_SHIFT)); + range[nr_range].end = mtrr_tom2 >> PAGE_SHIFT; + if (highest_pfn < range[nr_range].end) + highest_pfn = range[nr_range].end; + nr_range++; + } + nr_range = x86_get_mtrr_mem_range(range, nr_range, 0, 0); + + /* Check the head: */ + total_trim_size = 0; + if (range[0].start) + total_trim_size += real_trim_memory(0, range[0].start); + + /* Check the holes: */ + for (i = 0; i < nr_range - 1; i++) { + if (range[i].end < range[i+1].start) + total_trim_size += real_trim_memory(range[i].end, + range[i+1].start); + } + + /* Check the top: */ + i = nr_range - 1; + if (range[i].end < end_pfn) + total_trim_size += real_trim_memory(range[i].end, + end_pfn); + + if (total_trim_size) { + pr_warn("WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing %lluMB of RAM.\n", + total_trim_size >> 20); + + if (!changed_by_mtrr_cleanup) + WARN_ON(1); + + pr_info("update e820 for mtrr\n"); + e820__update_table_print(); + + return 1; + } + + return 0; +} diff --git a/arch/x86/kernel/cpu/mtrr/cyrix.c b/arch/x86/kernel/cpu/mtrr/cyrix.c new file mode 100644 index 0000000000..238dad57d4 --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/cyrix.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/init.h> +#include <linux/io.h> +#include <linux/mm.h> + +#include <asm/processor-cyrix.h> +#include <asm/processor-flags.h> +#include <asm/mtrr.h> +#include <asm/msr.h> + +#include "mtrr.h" + +static void +cyrix_get_arr(unsigned int reg, unsigned long *base, + unsigned long *size, mtrr_type * type) +{ + unsigned char arr, ccr3, rcr, shift; + unsigned long flags; + + arr = CX86_ARR_BASE + (reg << 1) + reg; /* avoid multiplication by 3 */ + + local_irq_save(flags); + + ccr3 = getCx86(CX86_CCR3); + setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */ + ((unsigned char *)base)[3] = getCx86(arr); + ((unsigned char *)base)[2] = getCx86(arr + 1); + ((unsigned char *)base)[1] = getCx86(arr + 2); + rcr = getCx86(CX86_RCR_BASE + reg); + setCx86(CX86_CCR3, ccr3); /* disable MAPEN */ + + local_irq_restore(flags); + + shift = ((unsigned char *) base)[1] & 0x0f; + *base >>= PAGE_SHIFT; + + /* + * Power of two, at least 4K on ARR0-ARR6, 256K on ARR7 + * Note: shift==0xf means 4G, this is unsupported. + */ + if (shift) + *size = (reg < 7 ? 0x1UL : 0x40UL) << (shift - 1); + else + *size = 0; + + /* Bit 0 is Cache Enable on ARR7, Cache Disable on ARR0-ARR6 */ + if (reg < 7) { + switch (rcr) { + case 1: + *type = MTRR_TYPE_UNCACHABLE; + break; + case 8: + *type = MTRR_TYPE_WRBACK; + break; + case 9: + *type = MTRR_TYPE_WRCOMB; + break; + case 24: + default: + *type = MTRR_TYPE_WRTHROUGH; + break; + } + } else { + switch (rcr) { + case 0: + *type = MTRR_TYPE_UNCACHABLE; + break; + case 8: + *type = MTRR_TYPE_WRCOMB; + break; + case 9: + *type = MTRR_TYPE_WRBACK; + break; + case 25: + default: + *type = MTRR_TYPE_WRTHROUGH; + break; + } + } +} + +/* + * cyrix_get_free_region - get a free ARR. + * + * @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 +cyrix_get_free_region(unsigned long base, unsigned long size, int replace_reg) +{ + unsigned long lbase, lsize; + mtrr_type ltype; + int i; + + switch (replace_reg) { + case 7: + if (size < 0x40) + break; + fallthrough; + case 6: + case 5: + case 4: + return replace_reg; + case 3: + case 2: + case 1: + case 0: + return replace_reg; + } + /* If we are to set up a region >32M then look at ARR7 immediately */ + if (size > 0x2000) { + cyrix_get_arr(7, &lbase, &lsize, <ype); + if (lsize == 0) + return 7; + /* Else try ARR0-ARR6 first */ + } else { + for (i = 0; i < 7; i++) { + cyrix_get_arr(i, &lbase, &lsize, <ype); + if (lsize == 0) + return i; + } + /* + * ARR0-ARR6 isn't free + * try ARR7 but its size must be at least 256K + */ + cyrix_get_arr(i, &lbase, &lsize, <ype); + if ((lsize == 0) && (size >= 0x40)) + return i; + } + return -ENOSPC; +} + +static u32 cr4, ccr3; + +static void prepare_set(void) +{ + u32 cr0; + + /* Save value of CR4 and clear Page Global Enable (bit 7) */ + if (boot_cpu_has(X86_FEATURE_PGE)) { + cr4 = __read_cr4(); + __write_cr4(cr4 & ~X86_CR4_PGE); + } + + /* + * Disable and flush caches. + * Note that wbinvd flushes the TLBs as a side-effect + */ + cr0 = read_cr0() | X86_CR0_CD; + wbinvd(); + write_cr0(cr0); + wbinvd(); + + /* Cyrix ARRs - everything else was excluded at the top */ + ccr3 = getCx86(CX86_CCR3); + + /* Cyrix ARRs - everything else was excluded at the top */ + setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); +} + +static void post_set(void) +{ + /* Flush caches and TLBs */ + wbinvd(); + + /* Cyrix ARRs - everything else was excluded at the top */ + setCx86(CX86_CCR3, ccr3); + + /* Enable caches */ + write_cr0(read_cr0() & ~X86_CR0_CD); + + /* Restore value of CR4 */ + if (boot_cpu_has(X86_FEATURE_PGE)) + __write_cr4(cr4); +} + +static void cyrix_set_arr(unsigned int reg, unsigned long base, + unsigned long size, mtrr_type type) +{ + unsigned char arr, arr_type, arr_size; + + arr = CX86_ARR_BASE + (reg << 1) + reg; /* avoid multiplication by 3 */ + + /* count down from 32M (ARR0-ARR6) or from 2G (ARR7) */ + if (reg >= 7) + size >>= 6; + + size &= 0x7fff; /* make sure arr_size <= 14 */ + for (arr_size = 0; size; arr_size++, size >>= 1) + ; + + if (reg < 7) { + switch (type) { + case MTRR_TYPE_UNCACHABLE: + arr_type = 1; + break; + case MTRR_TYPE_WRCOMB: + arr_type = 9; + break; + case MTRR_TYPE_WRTHROUGH: + arr_type = 24; + break; + default: + arr_type = 8; + break; + } + } else { + switch (type) { + case MTRR_TYPE_UNCACHABLE: + arr_type = 0; + break; + case MTRR_TYPE_WRCOMB: + arr_type = 8; + break; + case MTRR_TYPE_WRTHROUGH: + arr_type = 25; + break; + default: + arr_type = 9; + break; + } + } + + prepare_set(); + + base <<= PAGE_SHIFT; + setCx86(arr + 0, ((unsigned char *)&base)[3]); + setCx86(arr + 1, ((unsigned char *)&base)[2]); + setCx86(arr + 2, (((unsigned char *)&base)[1]) | arr_size); + setCx86(CX86_RCR_BASE + reg, arr_type); + + post_set(); +} + +const struct mtrr_ops cyrix_mtrr_ops = { + .var_regs = 8, + .set = cyrix_set_arr, + .get = cyrix_get_arr, + .get_free_region = cyrix_get_free_region, + .validate_add_page = generic_validate_add_page, + .have_wrcomb = positive_have_wrcomb, +}; diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c new file mode 100644 index 0000000000..2d6aa5d2e3 --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/generic.c @@ -0,0 +1,1070 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This only handles 32bit MTRR on 32bit hosts. This is strictly wrong + * because MTRRs can span up to 40 bits (36bits on most modern x86) + */ + +#include <linux/export.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/mm.h> +#include <linux/cc_platform.h> +#include <asm/processor-flags.h> +#include <asm/cacheinfo.h> +#include <asm/cpufeature.h> +#include <asm/hypervisor.h> +#include <asm/mshyperv.h> +#include <asm/tlbflush.h> +#include <asm/mtrr.h> +#include <asm/msr.h> +#include <asm/memtype.h> + +#include "mtrr.h" + +struct fixed_range_block { + int base_msr; /* start address of an MTRR block */ + int ranges; /* number of MTRRs in this block */ +}; + +static struct fixed_range_block fixed_range_blocks[] = { + { MSR_MTRRfix64K_00000, 1 }, /* one 64k MTRR */ + { MSR_MTRRfix16K_80000, 2 }, /* two 16k MTRRs */ + { MSR_MTRRfix4K_C0000, 8 }, /* eight 4k MTRRs */ + {} +}; + +struct cache_map { + u64 start; + u64 end; + u64 flags; + u64 type:8; + u64 fixed:1; +}; + +bool mtrr_debug; + +static int __init mtrr_param_setup(char *str) +{ + int rc = 0; + + if (!str) + return -EINVAL; + if (!strcmp(str, "debug")) + mtrr_debug = true; + else + rc = -EINVAL; + + return rc; +} +early_param("mtrr", mtrr_param_setup); + +/* + * CACHE_MAP_MAX is the maximum number of memory ranges in cache_map, where + * no 2 adjacent ranges have the same cache mode (those would be merged). + * The number is based on the worst case: + * - no two adjacent fixed MTRRs share the same cache mode + * - one variable MTRR is spanning a huge area with mode WB + * - 255 variable MTRRs with mode UC all overlap with the WB MTRR, creating 2 + * additional ranges each (result like "ababababa...aba" with a = WB, b = UC), + * accounting for MTRR_MAX_VAR_RANGES * 2 - 1 range entries + * - a TOP_MEM2 area (even with overlapping an UC MTRR can't add 2 range entries + * to the possible maximum, as it always starts at 4GB, thus it can't be in + * the middle of that MTRR, unless that MTRR starts at 0, which would remove + * the initial "a" from the "abababa" pattern above) + * The map won't contain ranges with no matching MTRR (those fall back to the + * default cache mode). + */ +#define CACHE_MAP_MAX (MTRR_NUM_FIXED_RANGES + MTRR_MAX_VAR_RANGES * 2) + +static struct cache_map init_cache_map[CACHE_MAP_MAX] __initdata; +static struct cache_map *cache_map __refdata = init_cache_map; +static unsigned int cache_map_size = CACHE_MAP_MAX; +static unsigned int cache_map_n; +static unsigned int cache_map_fixed; + +static unsigned long smp_changes_mask; +static int mtrr_state_set; +u64 mtrr_tom2; + +struct mtrr_state_type mtrr_state; +EXPORT_SYMBOL_GPL(mtrr_state); + +/* Reserved bits in the high portion of the MTRRphysBaseN MSR. */ +u32 phys_hi_rsvd; + +/* + * BIOS is expected to clear MtrrFixDramModEn bit, see for example + * "BIOS and Kernel Developer's Guide for the AMD Athlon 64 and AMD + * Opteron Processors" (26094 Rev. 3.30 February 2006), section + * "13.2.1.2 SYSCFG Register": "The MtrrFixDramModEn bit should be set + * to 1 during BIOS initialization of the fixed MTRRs, then cleared to + * 0 for operation." + */ +static inline void k8_check_syscfg_dram_mod_en(void) +{ + u32 lo, hi; + + if (!((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && + (boot_cpu_data.x86 >= 0x0f))) + return; + + rdmsr(MSR_AMD64_SYSCFG, lo, hi); + if (lo & K8_MTRRFIXRANGE_DRAM_MODIFY) { + pr_err(FW_WARN "MTRR: CPU %u: SYSCFG[MtrrFixDramModEn]" + " not cleared by BIOS, clearing this bit\n", + smp_processor_id()); + lo &= ~K8_MTRRFIXRANGE_DRAM_MODIFY; + mtrr_wrmsr(MSR_AMD64_SYSCFG, lo, hi); + } +} + +/* Get the size of contiguous MTRR range */ +static u64 get_mtrr_size(u64 mask) +{ + u64 size; + + mask |= (u64)phys_hi_rsvd << 32; + size = -mask; + + return size; +} + +static u8 get_var_mtrr_state(unsigned int reg, u64 *start, u64 *size) +{ + struct mtrr_var_range *mtrr = mtrr_state.var_ranges + reg; + + if (!(mtrr->mask_lo & MTRR_PHYSMASK_V)) + return MTRR_TYPE_INVALID; + + *start = (((u64)mtrr->base_hi) << 32) + (mtrr->base_lo & PAGE_MASK); + *size = get_mtrr_size((((u64)mtrr->mask_hi) << 32) + + (mtrr->mask_lo & PAGE_MASK)); + + return mtrr->base_lo & MTRR_PHYSBASE_TYPE; +} + +static u8 get_effective_type(u8 type1, u8 type2) +{ + if (type1 == MTRR_TYPE_UNCACHABLE || type2 == MTRR_TYPE_UNCACHABLE) + return MTRR_TYPE_UNCACHABLE; + + if ((type1 == MTRR_TYPE_WRBACK && type2 == MTRR_TYPE_WRTHROUGH) || + (type1 == MTRR_TYPE_WRTHROUGH && type2 == MTRR_TYPE_WRBACK)) + return MTRR_TYPE_WRTHROUGH; + + if (type1 != type2) + return MTRR_TYPE_UNCACHABLE; + + return type1; +} + +static void rm_map_entry_at(int idx) +{ + cache_map_n--; + if (cache_map_n > idx) { + memmove(cache_map + idx, cache_map + idx + 1, + sizeof(*cache_map) * (cache_map_n - idx)); + } +} + +/* + * Add an entry into cache_map at a specific index. Merges adjacent entries if + * appropriate. Return the number of merges for correcting the scan index + * (this is needed as merging will reduce the number of entries, which will + * result in skipping entries in future iterations if the scan index isn't + * corrected). + * Note that the corrected index can never go below -1 (resulting in being 0 in + * the next scan iteration), as "2" is returned only if the current index is + * larger than zero. + */ +static int add_map_entry_at(u64 start, u64 end, u8 type, int idx) +{ + bool merge_prev = false, merge_next = false; + + if (start >= end) + return 0; + + if (idx > 0) { + struct cache_map *prev = cache_map + idx - 1; + + if (!prev->fixed && start == prev->end && type == prev->type) + merge_prev = true; + } + + if (idx < cache_map_n) { + struct cache_map *next = cache_map + idx; + + if (!next->fixed && end == next->start && type == next->type) + merge_next = true; + } + + if (merge_prev && merge_next) { + cache_map[idx - 1].end = cache_map[idx].end; + rm_map_entry_at(idx); + return 2; + } + if (merge_prev) { + cache_map[idx - 1].end = end; + return 1; + } + if (merge_next) { + cache_map[idx].start = start; + return 1; + } + + /* Sanity check: the array should NEVER be too small! */ + if (cache_map_n == cache_map_size) { + WARN(1, "MTRR cache mode memory map exhausted!\n"); + cache_map_n = cache_map_fixed; + return 0; + } + + if (cache_map_n > idx) { + memmove(cache_map + idx + 1, cache_map + idx, + sizeof(*cache_map) * (cache_map_n - idx)); + } + + cache_map[idx].start = start; + cache_map[idx].end = end; + cache_map[idx].type = type; + cache_map[idx].fixed = 0; + cache_map_n++; + + return 0; +} + +/* Clear a part of an entry. Return 1 if start of entry is still valid. */ +static int clr_map_range_at(u64 start, u64 end, int idx) +{ + int ret = start != cache_map[idx].start; + u64 tmp; + + if (start == cache_map[idx].start && end == cache_map[idx].end) { + rm_map_entry_at(idx); + } else if (start == cache_map[idx].start) { + cache_map[idx].start = end; + } else if (end == cache_map[idx].end) { + cache_map[idx].end = start; + } else { + tmp = cache_map[idx].end; + cache_map[idx].end = start; + add_map_entry_at(end, tmp, cache_map[idx].type, idx + 1); + } + + return ret; +} + +/* + * Add MTRR to the map. The current map is scanned and each part of the MTRR + * either overlapping with an existing entry or with a hole in the map is + * handled separately. + */ +static void add_map_entry(u64 start, u64 end, u8 type) +{ + u8 new_type, old_type; + u64 tmp; + int i; + + for (i = 0; i < cache_map_n && start < end; i++) { + if (start >= cache_map[i].end) + continue; + + if (start < cache_map[i].start) { + /* Region start has no overlap. */ + tmp = min(end, cache_map[i].start); + i -= add_map_entry_at(start, tmp, type, i); + start = tmp; + continue; + } + + new_type = get_effective_type(type, cache_map[i].type); + old_type = cache_map[i].type; + + if (cache_map[i].fixed || new_type == old_type) { + /* Cut off start of new entry. */ + start = cache_map[i].end; + continue; + } + + /* Handle only overlapping part of region. */ + tmp = min(end, cache_map[i].end); + i += clr_map_range_at(start, tmp, i); + i -= add_map_entry_at(start, tmp, new_type, i); + start = tmp; + } + + /* Add rest of region after last map entry (rest might be empty). */ + add_map_entry_at(start, end, type, i); +} + +/* Add variable MTRRs to cache map. */ +static void map_add_var(void) +{ + u64 start, size; + unsigned int i; + u8 type; + + /* + * Add AMD TOP_MEM2 area. Can't be added in mtrr_build_map(), as it + * needs to be added again when rebuilding the map due to potentially + * having moved as a result of variable MTRRs for memory below 4GB. + */ + if (mtrr_tom2) { + add_map_entry(BIT_ULL(32), mtrr_tom2, MTRR_TYPE_WRBACK); + cache_map[cache_map_n - 1].fixed = 1; + } + + for (i = 0; i < num_var_ranges; i++) { + type = get_var_mtrr_state(i, &start, &size); + if (type != MTRR_TYPE_INVALID) + add_map_entry(start, start + size, type); + } +} + +/* + * Rebuild map by replacing variable entries. Needs to be called when MTRR + * registers are being changed after boot, as such changes could include + * removals of registers, which are complicated to handle without rebuild of + * the map. + */ +void generic_rebuild_map(void) +{ + if (mtrr_if != &generic_mtrr_ops) + return; + + cache_map_n = cache_map_fixed; + + map_add_var(); +} + +static unsigned int __init get_cache_map_size(void) +{ + return cache_map_fixed + 2 * num_var_ranges + (mtrr_tom2 != 0); +} + +/* Build the cache_map containing the cache modes per memory range. */ +void __init mtrr_build_map(void) +{ + u64 start, end, size; + unsigned int i; + u8 type; + + /* Add fixed MTRRs, optimize for adjacent entries with same type. */ + if (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED) { + /* + * Start with 64k size fixed entries, preset 1st one (hence the + * loop below is starting with index 1). + */ + start = 0; + end = size = 0x10000; + type = mtrr_state.fixed_ranges[0]; + + for (i = 1; i < MTRR_NUM_FIXED_RANGES; i++) { + /* 8 64k entries, then 16 16k ones, rest 4k. */ + if (i == 8 || i == 24) + size >>= 2; + + if (mtrr_state.fixed_ranges[i] != type) { + add_map_entry(start, end, type); + start = end; + type = mtrr_state.fixed_ranges[i]; + } + end += size; + } + add_map_entry(start, end, type); + } + + /* Mark fixed, they take precedence. */ + for (i = 0; i < cache_map_n; i++) + cache_map[i].fixed = 1; + cache_map_fixed = cache_map_n; + + map_add_var(); + + pr_info("MTRR map: %u entries (%u fixed + %u variable; max %u), built from %u variable MTRRs\n", + cache_map_n, cache_map_fixed, cache_map_n - cache_map_fixed, + get_cache_map_size(), num_var_ranges + (mtrr_tom2 != 0)); + + if (mtrr_debug) { + for (i = 0; i < cache_map_n; i++) { + pr_info("%3u: %016llx-%016llx %s\n", i, + cache_map[i].start, cache_map[i].end - 1, + mtrr_attrib_to_str(cache_map[i].type)); + } + } +} + +/* Copy the cache_map from __initdata memory to dynamically allocated one. */ +void __init mtrr_copy_map(void) +{ + unsigned int new_size = get_cache_map_size(); + + if (!mtrr_state.enabled || !new_size) { + cache_map = NULL; + return; + } + + mutex_lock(&mtrr_mutex); + + cache_map = kcalloc(new_size, sizeof(*cache_map), GFP_KERNEL); + if (cache_map) { + memmove(cache_map, init_cache_map, + cache_map_n * sizeof(*cache_map)); + cache_map_size = new_size; + } else { + mtrr_state.enabled = 0; + pr_err("MTRRs disabled due to allocation failure for lookup map.\n"); + } + + mutex_unlock(&mtrr_mutex); +} + +/** + * mtrr_overwrite_state - set static MTRR state + * + * Used to set MTRR state via different means (e.g. with data obtained from + * a hypervisor). + * Is allowed only for special cases when running virtualized. Must be called + * from the x86_init.hyper.init_platform() hook. It can be called only once. + * The MTRR state can't be changed afterwards. To ensure that, X86_FEATURE_MTRR + * is cleared. + */ +void mtrr_overwrite_state(struct mtrr_var_range *var, unsigned int num_var, + mtrr_type def_type) +{ + unsigned int i; + + /* Only allowed to be called once before mtrr_bp_init(). */ + if (WARN_ON_ONCE(mtrr_state_set)) + return; + + /* Only allowed when running virtualized. */ + if (!cpu_feature_enabled(X86_FEATURE_HYPERVISOR)) + return; + + /* + * Only allowed for special virtualization cases: + * - when running as Hyper-V, SEV-SNP guest using vTOM + * - when running as Xen PV guest + * - when running as SEV-SNP or TDX guest to avoid unnecessary + * VMM communication/Virtualization exceptions (#VC, #VE) + */ + if (!cc_platform_has(CC_ATTR_GUEST_SEV_SNP) && + !hv_is_isolation_supported() && + !cpu_feature_enabled(X86_FEATURE_XENPV) && + !cpu_feature_enabled(X86_FEATURE_TDX_GUEST)) + return; + + /* Disable MTRR in order to disable MTRR modifications. */ + setup_clear_cpu_cap(X86_FEATURE_MTRR); + + if (var) { + if (num_var > MTRR_MAX_VAR_RANGES) { + pr_warn("Trying to overwrite MTRR state with %u variable entries\n", + num_var); + num_var = MTRR_MAX_VAR_RANGES; + } + for (i = 0; i < num_var; i++) + mtrr_state.var_ranges[i] = var[i]; + num_var_ranges = num_var; + } + + mtrr_state.def_type = def_type; + mtrr_state.enabled |= MTRR_STATE_MTRR_ENABLED; + + mtrr_state_set = 1; +} + +static u8 type_merge(u8 type, u8 new_type, u8 *uniform) +{ + u8 effective_type; + + if (type == MTRR_TYPE_INVALID) + return new_type; + + effective_type = get_effective_type(type, new_type); + if (type != effective_type) + *uniform = 0; + + return effective_type; +} + +/** + * mtrr_type_lookup - look up memory type in MTRR + * + * Return Values: + * MTRR_TYPE_(type) - The effective MTRR type for the region + * MTRR_TYPE_INVALID - MTRR is disabled + * + * Output Argument: + * uniform - Set to 1 when the returned MTRR type is valid for the whole + * region, set to 0 else. + */ +u8 mtrr_type_lookup(u64 start, u64 end, u8 *uniform) +{ + u8 type = MTRR_TYPE_INVALID; + unsigned int i; + + if (!mtrr_state_set) { + /* Uniformity is unknown. */ + *uniform = 0; + return MTRR_TYPE_UNCACHABLE; + } + + *uniform = 1; + + if (!(mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED)) + return MTRR_TYPE_UNCACHABLE; + + for (i = 0; i < cache_map_n && start < end; i++) { + /* Region after current map entry? -> continue with next one. */ + if (start >= cache_map[i].end) + continue; + + /* Start of region not covered by current map entry? */ + if (start < cache_map[i].start) { + /* At least some part of region has default type. */ + type = type_merge(type, mtrr_state.def_type, uniform); + /* End of region not covered, too? -> lookup done. */ + if (end <= cache_map[i].start) + return type; + } + + /* At least part of region covered by map entry. */ + type = type_merge(type, cache_map[i].type, uniform); + + start = cache_map[i].end; + } + + /* End of region past last entry in map? -> use default type. */ + if (start < end) + type = type_merge(type, mtrr_state.def_type, uniform); + + return type; +} + +/* Get the MSR pair relating to a var range */ +static void +get_mtrr_var_range(unsigned int index, struct mtrr_var_range *vr) +{ + rdmsr(MTRRphysBase_MSR(index), vr->base_lo, vr->base_hi); + rdmsr(MTRRphysMask_MSR(index), vr->mask_lo, vr->mask_hi); +} + +/* Fill the MSR pair relating to a var range */ +void fill_mtrr_var_range(unsigned int index, + u32 base_lo, u32 base_hi, u32 mask_lo, u32 mask_hi) +{ + struct mtrr_var_range *vr; + + vr = mtrr_state.var_ranges; + + vr[index].base_lo = base_lo; + vr[index].base_hi = base_hi; + vr[index].mask_lo = mask_lo; + vr[index].mask_hi = mask_hi; +} + +static void get_fixed_ranges(mtrr_type *frs) +{ + unsigned int *p = (unsigned int *)frs; + int i; + + k8_check_syscfg_dram_mod_en(); + + rdmsr(MSR_MTRRfix64K_00000, p[0], p[1]); + + for (i = 0; i < 2; i++) + rdmsr(MSR_MTRRfix16K_80000 + i, p[2 + i * 2], p[3 + i * 2]); + for (i = 0; i < 8; i++) + rdmsr(MSR_MTRRfix4K_C0000 + i, p[6 + i * 2], p[7 + i * 2]); +} + +void mtrr_save_fixed_ranges(void *info) +{ + if (boot_cpu_has(X86_FEATURE_MTRR)) + get_fixed_ranges(mtrr_state.fixed_ranges); +} + +static unsigned __initdata last_fixed_start; +static unsigned __initdata last_fixed_end; +static mtrr_type __initdata last_fixed_type; + +static void __init print_fixed_last(void) +{ + if (!last_fixed_end) + return; + + pr_info(" %05X-%05X %s\n", last_fixed_start, + last_fixed_end - 1, mtrr_attrib_to_str(last_fixed_type)); + + last_fixed_end = 0; +} + +static void __init update_fixed_last(unsigned base, unsigned end, + mtrr_type type) +{ + last_fixed_start = base; + last_fixed_end = end; + last_fixed_type = type; +} + +static void __init +print_fixed(unsigned base, unsigned step, const mtrr_type *types) +{ + unsigned i; + + for (i = 0; i < 8; ++i, ++types, base += step) { + if (last_fixed_end == 0) { + update_fixed_last(base, base + step, *types); + continue; + } + if (last_fixed_end == base && last_fixed_type == *types) { + last_fixed_end = base + step; + continue; + } + /* new segments: gap or different type */ + print_fixed_last(); + update_fixed_last(base, base + step, *types); + } +} + +static void __init print_mtrr_state(void) +{ + unsigned int i; + int high_width; + + pr_info("MTRR default type: %s\n", + mtrr_attrib_to_str(mtrr_state.def_type)); + if (mtrr_state.have_fixed) { + pr_info("MTRR fixed ranges %sabled:\n", + ((mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED) && + (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) ? + "en" : "dis"); + print_fixed(0x00000, 0x10000, mtrr_state.fixed_ranges + 0); + for (i = 0; i < 2; ++i) + print_fixed(0x80000 + i * 0x20000, 0x04000, + mtrr_state.fixed_ranges + (i + 1) * 8); + for (i = 0; i < 8; ++i) + print_fixed(0xC0000 + i * 0x08000, 0x01000, + mtrr_state.fixed_ranges + (i + 3) * 8); + + /* tail */ + print_fixed_last(); + } + pr_info("MTRR variable ranges %sabled:\n", + mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED ? "en" : "dis"); + high_width = (boot_cpu_data.x86_phys_bits - (32 - PAGE_SHIFT) + 3) / 4; + + for (i = 0; i < num_var_ranges; ++i) { + if (mtrr_state.var_ranges[i].mask_lo & MTRR_PHYSMASK_V) + pr_info(" %u base %0*X%05X000 mask %0*X%05X000 %s\n", + i, + high_width, + mtrr_state.var_ranges[i].base_hi, + mtrr_state.var_ranges[i].base_lo >> 12, + high_width, + mtrr_state.var_ranges[i].mask_hi, + mtrr_state.var_ranges[i].mask_lo >> 12, + mtrr_attrib_to_str(mtrr_state.var_ranges[i].base_lo & + MTRR_PHYSBASE_TYPE)); + else + pr_info(" %u disabled\n", i); + } + if (mtrr_tom2) + pr_info("TOM2: %016llx aka %lldM\n", mtrr_tom2, mtrr_tom2>>20); +} + +/* Grab all of the MTRR state for this CPU into *state */ +bool __init get_mtrr_state(void) +{ + struct mtrr_var_range *vrs; + unsigned lo, dummy; + unsigned int i; + + vrs = mtrr_state.var_ranges; + + rdmsr(MSR_MTRRcap, lo, dummy); + mtrr_state.have_fixed = lo & MTRR_CAP_FIX; + + for (i = 0; i < num_var_ranges; i++) + get_mtrr_var_range(i, &vrs[i]); + if (mtrr_state.have_fixed) + get_fixed_ranges(mtrr_state.fixed_ranges); + + rdmsr(MSR_MTRRdefType, lo, dummy); + mtrr_state.def_type = lo & MTRR_DEF_TYPE_TYPE; + mtrr_state.enabled = (lo & MTRR_DEF_TYPE_ENABLE) >> MTRR_STATE_SHIFT; + + if (amd_special_default_mtrr()) { + unsigned low, high; + + /* TOP_MEM2 */ + rdmsr(MSR_K8_TOP_MEM2, low, high); + mtrr_tom2 = high; + mtrr_tom2 <<= 32; + mtrr_tom2 |= low; + mtrr_tom2 &= 0xffffff800000ULL; + } + + if (mtrr_debug) + print_mtrr_state(); + + mtrr_state_set = 1; + + return !!(mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED); +} + +/* Some BIOS's are messed up and don't set all MTRRs the same! */ +void __init mtrr_state_warn(void) +{ + unsigned long mask = smp_changes_mask; + + if (!mask) + return; + if (mask & MTRR_CHANGE_MASK_FIXED) + pr_warn("mtrr: your CPUs had inconsistent fixed MTRR settings\n"); + if (mask & MTRR_CHANGE_MASK_VARIABLE) + pr_warn("mtrr: your CPUs had inconsistent variable MTRR settings\n"); + if (mask & MTRR_CHANGE_MASK_DEFTYPE) + pr_warn("mtrr: your CPUs had inconsistent MTRRdefType settings\n"); + + pr_info("mtrr: probably your BIOS does not setup all CPUs.\n"); + pr_info("mtrr: corrected configuration.\n"); +} + +/* + * Doesn't attempt to pass an error out to MTRR users + * because it's quite complicated in some cases and probably not + * worth it because the best error handling is to ignore it. + */ +void mtrr_wrmsr(unsigned msr, unsigned a, unsigned b) +{ + if (wrmsr_safe(msr, a, b) < 0) { + pr_err("MTRR: CPU %u: Writing MSR %x to %x:%x failed\n", + smp_processor_id(), msr, a, b); + } +} + +/** + * set_fixed_range - checks & updates a fixed-range MTRR if it + * differs from the value it should have + * @msr: MSR address of the MTTR which should be checked and updated + * @changed: pointer which indicates whether the MTRR needed to be changed + * @msrwords: pointer to the MSR values which the MSR should have + */ +static void set_fixed_range(int msr, bool *changed, unsigned int *msrwords) +{ + unsigned lo, hi; + + rdmsr(msr, lo, hi); + + if (lo != msrwords[0] || hi != msrwords[1]) { + mtrr_wrmsr(msr, msrwords[0], msrwords[1]); + *changed = true; + } +} + +/** + * generic_get_free_region - Get a free MTRR. + * @base: The starting (base) address of the region. + * @size: The size (in bytes) of the region. + * @replace_reg: mtrr index to be replaced; set to invalid value if none. + * + * Returns: The index of the region on success, else negative on error. + */ +int +generic_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) { + mtrr_if->get(i, &lbase, &lsize, <ype); + if (lsize == 0) + return i; + } + + return -ENOSPC; +} + +static void generic_get_mtrr(unsigned int reg, unsigned long *base, + unsigned long *size, mtrr_type *type) +{ + u32 mask_lo, mask_hi, base_lo, base_hi; + unsigned int hi; + u64 tmp, mask; + + /* + * get_mtrr doesn't need to update mtrr_state, also it could be called + * from any cpu, so try to print it out directly. + */ + get_cpu(); + + rdmsr(MTRRphysMask_MSR(reg), mask_lo, mask_hi); + + if (!(mask_lo & MTRR_PHYSMASK_V)) { + /* Invalid (i.e. free) range */ + *base = 0; + *size = 0; + *type = 0; + goto out_put_cpu; + } + + rdmsr(MTRRphysBase_MSR(reg), base_lo, base_hi); + + /* Work out the shifted address mask: */ + tmp = (u64)mask_hi << 32 | (mask_lo & PAGE_MASK); + mask = (u64)phys_hi_rsvd << 32 | tmp; + + /* Expand tmp with high bits to all 1s: */ + hi = fls64(tmp); + if (hi > 0) { + tmp |= ~((1ULL<<(hi - 1)) - 1); + + if (tmp != mask) { + pr_warn("mtrr: your BIOS has configured an incorrect mask, fixing it.\n"); + add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); + mask = tmp; + } + } + + /* + * This works correctly if size is a power of two, i.e. a + * contiguous range: + */ + *size = -mask >> PAGE_SHIFT; + *base = (u64)base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT; + *type = base_lo & MTRR_PHYSBASE_TYPE; + +out_put_cpu: + put_cpu(); +} + +/** + * set_fixed_ranges - checks & updates the fixed-range MTRRs if they + * differ from the saved set + * @frs: pointer to fixed-range MTRR values, saved by get_fixed_ranges() + */ +static int set_fixed_ranges(mtrr_type *frs) +{ + unsigned long long *saved = (unsigned long long *)frs; + bool changed = false; + int block = -1, range; + + k8_check_syscfg_dram_mod_en(); + + while (fixed_range_blocks[++block].ranges) { + for (range = 0; range < fixed_range_blocks[block].ranges; range++) + set_fixed_range(fixed_range_blocks[block].base_msr + range, + &changed, (unsigned int *)saved++); + } + + return changed; +} + +/* + * Set the MSR pair relating to a var range. + * Returns true if changes are made. + */ +static bool set_mtrr_var_ranges(unsigned int index, struct mtrr_var_range *vr) +{ + unsigned int lo, hi; + bool changed = false; + + rdmsr(MTRRphysBase_MSR(index), lo, hi); + if ((vr->base_lo & ~MTRR_PHYSBASE_RSVD) != (lo & ~MTRR_PHYSBASE_RSVD) + || (vr->base_hi & ~phys_hi_rsvd) != (hi & ~phys_hi_rsvd)) { + + mtrr_wrmsr(MTRRphysBase_MSR(index), vr->base_lo, vr->base_hi); + changed = true; + } + + rdmsr(MTRRphysMask_MSR(index), lo, hi); + + if ((vr->mask_lo & ~MTRR_PHYSMASK_RSVD) != (lo & ~MTRR_PHYSMASK_RSVD) + || (vr->mask_hi & ~phys_hi_rsvd) != (hi & ~phys_hi_rsvd)) { + mtrr_wrmsr(MTRRphysMask_MSR(index), vr->mask_lo, vr->mask_hi); + changed = true; + } + return changed; +} + +static u32 deftype_lo, deftype_hi; + +/** + * set_mtrr_state - Set the MTRR state for this CPU. + * + * NOTE: The CPU must already be in a safe state for MTRR changes, including + * measures that only a single CPU can be active in set_mtrr_state() in + * order to not be subject to races for usage of deftype_lo. This is + * accomplished by taking cache_disable_lock. + * RETURNS: 0 if no changes made, else a mask indicating what was changed. + */ +static unsigned long set_mtrr_state(void) +{ + unsigned long change_mask = 0; + unsigned int i; + + for (i = 0; i < num_var_ranges; i++) { + if (set_mtrr_var_ranges(i, &mtrr_state.var_ranges[i])) + change_mask |= MTRR_CHANGE_MASK_VARIABLE; + } + + if (mtrr_state.have_fixed && set_fixed_ranges(mtrr_state.fixed_ranges)) + change_mask |= MTRR_CHANGE_MASK_FIXED; + + /* + * Set_mtrr_restore restores the old value of MTRRdefType, + * so to set it we fiddle with the saved value: + */ + if ((deftype_lo & MTRR_DEF_TYPE_TYPE) != mtrr_state.def_type || + ((deftype_lo & MTRR_DEF_TYPE_ENABLE) >> MTRR_STATE_SHIFT) != mtrr_state.enabled) { + + deftype_lo = (deftype_lo & MTRR_DEF_TYPE_DISABLE) | + mtrr_state.def_type | + (mtrr_state.enabled << MTRR_STATE_SHIFT); + change_mask |= MTRR_CHANGE_MASK_DEFTYPE; + } + + return change_mask; +} + +void mtrr_disable(void) +{ + /* Save MTRR state */ + rdmsr(MSR_MTRRdefType, deftype_lo, deftype_hi); + + /* Disable MTRRs, and set the default type to uncached */ + mtrr_wrmsr(MSR_MTRRdefType, deftype_lo & MTRR_DEF_TYPE_DISABLE, deftype_hi); +} + +void mtrr_enable(void) +{ + /* Intel (P6) standard MTRRs */ + mtrr_wrmsr(MSR_MTRRdefType, deftype_lo, deftype_hi); +} + +void mtrr_generic_set_state(void) +{ + unsigned long mask, count; + + /* Actually set the state */ + mask = set_mtrr_state(); + + /* Use the atomic bitops to update the global mask */ + for (count = 0; count < sizeof(mask) * 8; ++count) { + if (mask & 0x01) + set_bit(count, &smp_changes_mask); + mask >>= 1; + } +} + +/** + * generic_set_mtrr - set variable MTRR register on the local CPU. + * + * @reg: The register to set. + * @base: The base address of the region. + * @size: The size of the region. If this is 0 the region is disabled. + * @type: The type of the region. + * + * Returns nothing. + */ +static void generic_set_mtrr(unsigned int reg, unsigned long base, + unsigned long size, mtrr_type type) +{ + unsigned long flags; + struct mtrr_var_range *vr; + + vr = &mtrr_state.var_ranges[reg]; + + local_irq_save(flags); + cache_disable(); + + if (size == 0) { + /* + * The invalid bit is kept in the mask, so we simply + * clear the relevant mask register to disable a range. + */ + mtrr_wrmsr(MTRRphysMask_MSR(reg), 0, 0); + memset(vr, 0, sizeof(struct mtrr_var_range)); + } else { + vr->base_lo = base << PAGE_SHIFT | type; + vr->base_hi = (base >> (32 - PAGE_SHIFT)) & ~phys_hi_rsvd; + vr->mask_lo = -size << PAGE_SHIFT | MTRR_PHYSMASK_V; + vr->mask_hi = (-size >> (32 - PAGE_SHIFT)) & ~phys_hi_rsvd; + + mtrr_wrmsr(MTRRphysBase_MSR(reg), vr->base_lo, vr->base_hi); + mtrr_wrmsr(MTRRphysMask_MSR(reg), vr->mask_lo, vr->mask_hi); + } + + cache_enable(); + local_irq_restore(flags); +} + +int generic_validate_add_page(unsigned long base, unsigned long size, + unsigned int type) +{ + unsigned long lbase, last; + + /* + * For Intel PPro stepping <= 7 + * must be 4 MiB aligned and not touch 0x70000000 -> 0x7003FFFF + */ + if (mtrr_if == &generic_mtrr_ops && boot_cpu_data.x86 == 6 && + boot_cpu_data.x86_model == 1 && + boot_cpu_data.x86_stepping <= 7) { + if (base & ((1 << (22 - PAGE_SHIFT)) - 1)) { + pr_warn("mtrr: base(0x%lx000) is not 4 MiB aligned\n", base); + return -EINVAL; + } + if (!(base + size < 0x70000 || base > 0x7003F) && + (type == MTRR_TYPE_WRCOMB + || type == MTRR_TYPE_WRBACK)) { + pr_warn("mtrr: writable mtrr between 0x70000000 and 0x7003FFFF may hang the CPU.\n"); + return -EINVAL; + } + } + + /* + * Check upper bits of base and last are equal and lower bits are 0 + * for base and 1 for last + */ + last = base + size - 1; + for (lbase = base; !(lbase & 1) && (last & 1); + lbase = lbase >> 1, last = last >> 1) + ; + if (lbase != last) { + pr_warn("mtrr: base(0x%lx000) is not aligned on a size(0x%lx000) boundary\n", base, size); + return -EINVAL; + } + return 0; +} + +static int generic_have_wrcomb(void) +{ + unsigned long config, dummy; + rdmsr(MSR_MTRRcap, config, dummy); + return config & MTRR_CAP_WC; +} + +int positive_have_wrcomb(void) +{ + return 1; +} + +/* + * Generic structure... + */ +const struct mtrr_ops generic_mtrr_ops = { + .get = generic_get_mtrr, + .get_free_region = generic_get_free_region, + .set = generic_set_mtrr, + .validate_add_page = generic_validate_add_page, + .have_wrcomb = generic_have_wrcomb, +}; diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c new file mode 100644 index 0000000000..a5c506f6da --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/if.c @@ -0,0 +1,425 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/capability.h> +#include <linux/seq_file.h> +#include <linux/uaccess.h> +#include <linux/proc_fs.h> +#include <linux/ctype.h> +#include <linux/string.h> +#include <linux/slab.h> +#include <linux/init.h> + +#define LINE_SIZE 80 + +#include <asm/mtrr.h> + +#include "mtrr.h" + +#define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private) + +static const char *const mtrr_strings[MTRR_NUM_TYPES] = +{ + "uncachable", /* 0 */ + "write-combining", /* 1 */ + "?", /* 2 */ + "?", /* 3 */ + "write-through", /* 4 */ + "write-protect", /* 5 */ + "write-back", /* 6 */ +}; + +const char *mtrr_attrib_to_str(int x) +{ + return (x <= 6) ? mtrr_strings[x] : "?"; +} + +#ifdef CONFIG_PROC_FS + +static int +mtrr_file_add(unsigned long base, unsigned long size, + unsigned int type, bool increment, struct file *file, int page) +{ + unsigned int *fcount = FILE_FCOUNT(file); + int reg, max; + + max = num_var_ranges; + if (fcount == NULL) { + fcount = kcalloc(max, sizeof(*fcount), GFP_KERNEL); + if (!fcount) + return -ENOMEM; + FILE_FCOUNT(file) = fcount; + } + if (!page) { + if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) + return -EINVAL; + base >>= PAGE_SHIFT; + size >>= PAGE_SHIFT; + } + reg = mtrr_add_page(base, size, type, true); + if (reg >= 0) + ++fcount[reg]; + return reg; +} + +static int +mtrr_file_del(unsigned long base, unsigned long size, + struct file *file, int page) +{ + unsigned int *fcount = FILE_FCOUNT(file); + int reg; + + if (!page) { + if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) + return -EINVAL; + base >>= PAGE_SHIFT; + size >>= PAGE_SHIFT; + } + reg = mtrr_del_page(-1, base, size); + if (reg < 0) + return reg; + if (fcount == NULL) + return reg; + if (fcount[reg] < 1) + return -EINVAL; + --fcount[reg]; + return reg; +} + +/* + * seq_file can seek but we ignore it. + * + * Format of control line: + * "base=%Lx size=%Lx type=%s" or "disable=%d" + */ +static ssize_t +mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) +{ + int i, err; + unsigned long reg; + unsigned long long base, size; + char *ptr; + char line[LINE_SIZE]; + int length; + size_t linelen; + + memset(line, 0, LINE_SIZE); + + len = min_t(size_t, len, LINE_SIZE - 1); + length = strncpy_from_user(line, buf, len); + if (length < 0) + return length; + + linelen = strlen(line); + ptr = line + linelen - 1; + if (linelen && *ptr == '\n') + *ptr = '\0'; + + if (!strncmp(line, "disable=", 8)) { + reg = simple_strtoul(line + 8, &ptr, 0); + err = mtrr_del_page(reg, 0, 0); + if (err < 0) + return err; + return len; + } + + if (strncmp(line, "base=", 5)) + return -EINVAL; + + base = simple_strtoull(line + 5, &ptr, 0); + ptr = skip_spaces(ptr); + + if (strncmp(ptr, "size=", 5)) + return -EINVAL; + + size = simple_strtoull(ptr + 5, &ptr, 0); + if ((base & 0xfff) || (size & 0xfff)) + return -EINVAL; + ptr = skip_spaces(ptr); + + if (strncmp(ptr, "type=", 5)) + return -EINVAL; + ptr = skip_spaces(ptr + 5); + + i = match_string(mtrr_strings, MTRR_NUM_TYPES, ptr); + if (i < 0) + return i; + + base >>= PAGE_SHIFT; + size >>= PAGE_SHIFT; + err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true); + if (err < 0) + return err; + return len; +} + +static long +mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg) +{ + int err = 0; + mtrr_type type; + unsigned long base; + unsigned long size; + struct mtrr_sentry sentry; + struct mtrr_gentry gentry; + void __user *arg = (void __user *) __arg; + + memset(&gentry, 0, sizeof(gentry)); + + switch (cmd) { + case MTRRIOC_ADD_ENTRY: + case MTRRIOC_SET_ENTRY: + case MTRRIOC_DEL_ENTRY: + case MTRRIOC_KILL_ENTRY: + case MTRRIOC_ADD_PAGE_ENTRY: + case MTRRIOC_SET_PAGE_ENTRY: + case MTRRIOC_DEL_PAGE_ENTRY: + case MTRRIOC_KILL_PAGE_ENTRY: + if (copy_from_user(&sentry, arg, sizeof(sentry))) + return -EFAULT; + break; + case MTRRIOC_GET_ENTRY: + case MTRRIOC_GET_PAGE_ENTRY: + if (copy_from_user(&gentry, arg, sizeof(gentry))) + return -EFAULT; + break; +#ifdef CONFIG_COMPAT + case MTRRIOC32_ADD_ENTRY: + case MTRRIOC32_SET_ENTRY: + case MTRRIOC32_DEL_ENTRY: + case MTRRIOC32_KILL_ENTRY: + case MTRRIOC32_ADD_PAGE_ENTRY: + case MTRRIOC32_SET_PAGE_ENTRY: + case MTRRIOC32_DEL_PAGE_ENTRY: + case MTRRIOC32_KILL_PAGE_ENTRY: { + struct mtrr_sentry32 __user *s32; + + s32 = (struct mtrr_sentry32 __user *)__arg; + err = get_user(sentry.base, &s32->base); + err |= get_user(sentry.size, &s32->size); + err |= get_user(sentry.type, &s32->type); + if (err) + return err; + break; + } + case MTRRIOC32_GET_ENTRY: + case MTRRIOC32_GET_PAGE_ENTRY: { + struct mtrr_gentry32 __user *g32; + + g32 = (struct mtrr_gentry32 __user *)__arg; + err = get_user(gentry.regnum, &g32->regnum); + err |= get_user(gentry.base, &g32->base); + err |= get_user(gentry.size, &g32->size); + err |= get_user(gentry.type, &g32->type); + if (err) + return err; + break; + } +#endif + } + + switch (cmd) { + default: + return -ENOTTY; + case MTRRIOC_ADD_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_ADD_ENTRY: +#endif + err = + mtrr_file_add(sentry.base, sentry.size, sentry.type, true, + file, 0); + break; + case MTRRIOC_SET_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_SET_ENTRY: +#endif + err = mtrr_add(sentry.base, sentry.size, sentry.type, false); + break; + case MTRRIOC_DEL_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_DEL_ENTRY: +#endif + err = mtrr_file_del(sentry.base, sentry.size, file, 0); + break; + case MTRRIOC_KILL_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_KILL_ENTRY: +#endif + err = mtrr_del(-1, sentry.base, sentry.size); + break; + case MTRRIOC_GET_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_GET_ENTRY: +#endif + if (gentry.regnum >= num_var_ranges) + return -EINVAL; + mtrr_if->get(gentry.regnum, &base, &size, &type); + + /* Hide entries that go above 4GB */ + if (base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)) + || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))) + gentry.base = gentry.size = gentry.type = 0; + else { + gentry.base = base << PAGE_SHIFT; + gentry.size = size << PAGE_SHIFT; + gentry.type = type; + } + + break; + case MTRRIOC_ADD_PAGE_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_ADD_PAGE_ENTRY: +#endif + err = + mtrr_file_add(sentry.base, sentry.size, sentry.type, true, + file, 1); + break; + case MTRRIOC_SET_PAGE_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_SET_PAGE_ENTRY: +#endif + err = + mtrr_add_page(sentry.base, sentry.size, sentry.type, false); + break; + case MTRRIOC_DEL_PAGE_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_DEL_PAGE_ENTRY: +#endif + err = mtrr_file_del(sentry.base, sentry.size, file, 1); + break; + case MTRRIOC_KILL_PAGE_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_KILL_PAGE_ENTRY: +#endif + err = mtrr_del_page(-1, sentry.base, sentry.size); + break; + case MTRRIOC_GET_PAGE_ENTRY: +#ifdef CONFIG_COMPAT + case MTRRIOC32_GET_PAGE_ENTRY: +#endif + if (gentry.regnum >= num_var_ranges) + return -EINVAL; + mtrr_if->get(gentry.regnum, &base, &size, &type); + /* Hide entries that would overflow */ + if (size != (__typeof__(gentry.size))size) + gentry.base = gentry.size = gentry.type = 0; + else { + gentry.base = base; + gentry.size = size; + gentry.type = type; + } + break; + } + + if (err) + return err; + + switch (cmd) { + case MTRRIOC_GET_ENTRY: + case MTRRIOC_GET_PAGE_ENTRY: + if (copy_to_user(arg, &gentry, sizeof(gentry))) + err = -EFAULT; + break; +#ifdef CONFIG_COMPAT + case MTRRIOC32_GET_ENTRY: + case MTRRIOC32_GET_PAGE_ENTRY: { + struct mtrr_gentry32 __user *g32; + + g32 = (struct mtrr_gentry32 __user *)__arg; + err = put_user(gentry.base, &g32->base); + err |= put_user(gentry.size, &g32->size); + err |= put_user(gentry.regnum, &g32->regnum); + err |= put_user(gentry.type, &g32->type); + break; + } +#endif + } + return err; +} + +static int mtrr_close(struct inode *ino, struct file *file) +{ + unsigned int *fcount = FILE_FCOUNT(file); + int i, max; + + if (fcount != NULL) { + max = num_var_ranges; + for (i = 0; i < max; ++i) { + while (fcount[i] > 0) { + mtrr_del(i, 0, 0); + --fcount[i]; + } + } + kfree(fcount); + FILE_FCOUNT(file) = NULL; + } + return single_release(ino, file); +} + +static int mtrr_seq_show(struct seq_file *seq, void *offset) +{ + char factor; + int i, max; + mtrr_type type; + unsigned long base, size; + + max = num_var_ranges; + for (i = 0; i < max; i++) { + mtrr_if->get(i, &base, &size, &type); + if (size == 0) { + mtrr_usage_table[i] = 0; + continue; + } + if (size < (0x100000 >> PAGE_SHIFT)) { + /* less than 1MB */ + factor = 'K'; + size <<= PAGE_SHIFT - 10; + } else { + factor = 'M'; + size >>= 20 - PAGE_SHIFT; + } + /* Base can be > 32bit */ + seq_printf(seq, "reg%02i: base=0x%06lx000 (%5luMB), size=%5lu%cB, count=%d: %s\n", + i, base, base >> (20 - PAGE_SHIFT), + size, factor, + mtrr_usage_table[i], mtrr_attrib_to_str(type)); + } + return 0; +} + +static int mtrr_open(struct inode *inode, struct file *file) +{ + if (!mtrr_if) + return -EIO; + if (!mtrr_if->get) + return -ENXIO; + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + return single_open(file, mtrr_seq_show, NULL); +} + +static const struct proc_ops mtrr_proc_ops = { + .proc_open = mtrr_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_write = mtrr_write, + .proc_ioctl = mtrr_ioctl, +#ifdef CONFIG_COMPAT + .proc_compat_ioctl = mtrr_ioctl, +#endif + .proc_release = mtrr_close, +}; + +static int __init mtrr_if_init(void) +{ + struct cpuinfo_x86 *c = &boot_cpu_data; + + if ((!cpu_has(c, X86_FEATURE_MTRR)) && + (!cpu_has(c, X86_FEATURE_K6_MTRR)) && + (!cpu_has(c, X86_FEATURE_CYRIX_ARR)) && + (!cpu_has(c, X86_FEATURE_CENTAUR_MCR))) + return -ENODEV; + + proc_create("mtrr", S_IWUSR | S_IRUGO, NULL, &mtrr_proc_ops); + return 0; +} +arch_initcall(mtrr_if_init); +#endif /* CONFIG_PROC_FS */ diff --git a/arch/x86/kernel/cpu/mtrr/legacy.c b/arch/x86/kernel/cpu/mtrr/legacy.c new file mode 100644 index 0000000000..d25882fcf1 --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/legacy.c @@ -0,0 +1,90 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/syscore_ops.h> +#include <asm/cpufeature.h> +#include <asm/mtrr.h> +#include <asm/processor.h> +#include "mtrr.h" + +void mtrr_set_if(void) +{ + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_AMD: + /* Pre-Athlon (K6) AMD CPU MTRRs */ + if (cpu_feature_enabled(X86_FEATURE_K6_MTRR)) + mtrr_if = &amd_mtrr_ops; + break; + case X86_VENDOR_CENTAUR: + if (cpu_feature_enabled(X86_FEATURE_CENTAUR_MCR)) + mtrr_if = ¢aur_mtrr_ops; + break; + case X86_VENDOR_CYRIX: + if (cpu_feature_enabled(X86_FEATURE_CYRIX_ARR)) + mtrr_if = &cyrix_mtrr_ops; + break; + default: + break; + } +} + +/* + * The suspend/resume methods are only for CPUs without MTRR. CPUs using generic + * MTRR driver don't require this. + */ +struct mtrr_value { + mtrr_type ltype; + unsigned long lbase; + unsigned long lsize; +}; + +static struct mtrr_value *mtrr_value; + +static int mtrr_save(void) +{ + int i; + + if (!mtrr_value) + return -ENOMEM; + + for (i = 0; i < num_var_ranges; i++) { + mtrr_if->get(i, &mtrr_value[i].lbase, + &mtrr_value[i].lsize, + &mtrr_value[i].ltype); + } + return 0; +} + +static void mtrr_restore(void) +{ + int i; + + for (i = 0; i < num_var_ranges; i++) { + if (mtrr_value[i].lsize) { + mtrr_if->set(i, mtrr_value[i].lbase, + mtrr_value[i].lsize, + mtrr_value[i].ltype); + } + } +} + +static struct syscore_ops mtrr_syscore_ops = { + .suspend = mtrr_save, + .resume = mtrr_restore, +}; + +void mtrr_register_syscore(void) +{ + mtrr_value = kcalloc(num_var_ranges, sizeof(*mtrr_value), GFP_KERNEL); + + /* + * The CPU has no MTRR and seems to not support SMP. They have + * specific drivers, we use a tricky method to support + * suspend/resume for them. + * + * TBD: is there any system with such CPU which supports + * suspend/resume? If no, we should remove the code. + */ + register_syscore_ops(&mtrr_syscore_ops); +} diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c new file mode 100644 index 0000000000..767bf1c71a --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/mtrr.c @@ -0,0 +1,640 @@ +/* Generic MTRR (Memory Type Range Register) driver. + + Copyright (C) 1997-2000 Richard Gooch + Copyright (c) 2002 Patrick Mochel + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the Free + Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + Richard Gooch may be reached by email at rgooch@atnf.csiro.au + The postal address is: + Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia. + + Source: "Pentium Pro Family Developer's Manual, Volume 3: + Operating System Writer's Guide" (Intel document number 242692), + section 11.11.7 + + This was cleaned and made readable by Patrick Mochel <mochel@osdl.org> + on 6-7 March 2002. + Source: Intel Architecture Software Developers Manual, Volume 3: + System Programming Guide; Section 9.11. (1997 edition - PPro). +*/ + +#include <linux/types.h> /* FIXME: kvm_para.h needs this */ + +#include <linux/stop_machine.h> +#include <linux/kvm_para.h> +#include <linux/uaccess.h> +#include <linux/export.h> +#include <linux/mutex.h> +#include <linux/init.h> +#include <linux/sort.h> +#include <linux/cpu.h> +#include <linux/pci.h> +#include <linux/smp.h> +#include <linux/syscore_ops.h> +#include <linux/rcupdate.h> + +#include <asm/cacheinfo.h> +#include <asm/cpufeature.h> +#include <asm/e820/api.h> +#include <asm/mtrr.h> +#include <asm/msr.h> +#include <asm/memtype.h> + +#include "mtrr.h" + +/* arch_phys_wc_add returns an MTRR register index plus this offset. */ +#define MTRR_TO_PHYS_WC_OFFSET 1000 + +u32 num_var_ranges; + +unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES]; +DEFINE_MUTEX(mtrr_mutex); + +const struct mtrr_ops *mtrr_if; + +/* Returns non-zero if we have the write-combining memory type */ +static int have_wrcomb(void) +{ + struct pci_dev *dev; + + dev = pci_get_class(PCI_CLASS_BRIDGE_HOST << 8, NULL); + if (dev != NULL) { + /* + * ServerWorks LE chipsets < rev 6 have problems with + * write-combining. Don't allow it and leave room for other + * chipsets to be tagged + */ + if (dev->vendor == PCI_VENDOR_ID_SERVERWORKS && + dev->device == PCI_DEVICE_ID_SERVERWORKS_LE && + dev->revision <= 5) { + pr_info("Serverworks LE rev < 6 detected. Write-combining disabled.\n"); + pci_dev_put(dev); + return 0; + } + /* + * Intel 450NX errata # 23. Non ascending cacheline evictions to + * write combining memory may resulting in data corruption + */ + if (dev->vendor == PCI_VENDOR_ID_INTEL && + dev->device == PCI_DEVICE_ID_INTEL_82451NX) { + pr_info("Intel 450NX MMC detected. Write-combining disabled.\n"); + pci_dev_put(dev); + return 0; + } + pci_dev_put(dev); + } + return mtrr_if->have_wrcomb ? mtrr_if->have_wrcomb() : 0; +} + +static void __init init_table(void) +{ + int i, max; + + max = num_var_ranges; + for (i = 0; i < max; i++) + mtrr_usage_table[i] = 1; +} + +struct set_mtrr_data { + unsigned long smp_base; + unsigned long smp_size; + unsigned int smp_reg; + mtrr_type smp_type; +}; + +/** + * mtrr_rendezvous_handler - Work done in the synchronization handler. Executed + * by all the CPUs. + * @info: pointer to mtrr configuration data + * + * Returns nothing. + */ +static int mtrr_rendezvous_handler(void *info) +{ + struct set_mtrr_data *data = info; + + mtrr_if->set(data->smp_reg, data->smp_base, + data->smp_size, data->smp_type); + return 0; +} + +static inline int types_compatible(mtrr_type type1, mtrr_type type2) +{ + return type1 == MTRR_TYPE_UNCACHABLE || + type2 == MTRR_TYPE_UNCACHABLE || + (type1 == MTRR_TYPE_WRTHROUGH && type2 == MTRR_TYPE_WRBACK) || + (type1 == MTRR_TYPE_WRBACK && type2 == MTRR_TYPE_WRTHROUGH); +} + +/** + * set_mtrr - update mtrrs on all processors + * @reg: mtrr in question + * @base: mtrr base + * @size: mtrr size + * @type: mtrr type + * + * This is kinda tricky, but fortunately, Intel spelled it out for us cleanly: + * + * 1. Queue work to do the following on all processors: + * 2. Disable Interrupts + * 3. Wait for all procs to do so + * 4. Enter no-fill cache mode + * 5. Flush caches + * 6. Clear PGE bit + * 7. Flush all TLBs + * 8. Disable all range registers + * 9. Update the MTRRs + * 10. Enable all range registers + * 11. Flush all TLBs and caches again + * 12. Enter normal cache mode and reenable caching + * 13. Set PGE + * 14. Wait for buddies to catch up + * 15. Enable interrupts. + * + * What does that mean for us? Well, stop_machine() will ensure that + * the rendezvous handler is started on each CPU. And in lockstep they + * do the state transition of disabling interrupts, updating MTRR's + * (the CPU vendors may each do it differently, so we call mtrr_if->set() + * callback and let them take care of it.) and enabling interrupts. + * + * Note that the mechanism is the same for UP systems, too; all the SMP stuff + * becomes nops. + */ +static void set_mtrr(unsigned int reg, unsigned long base, unsigned long size, + mtrr_type type) +{ + struct set_mtrr_data data = { .smp_reg = reg, + .smp_base = base, + .smp_size = size, + .smp_type = type + }; + + stop_machine_cpuslocked(mtrr_rendezvous_handler, &data, cpu_online_mask); + + generic_rebuild_map(); +} + +/** + * mtrr_add_page - Add a memory type region + * @base: Physical base address of region in pages (in units of 4 kB!) + * @size: Physical size of region in pages (4 kB) + * @type: Type of MTRR desired + * @increment: If this is true do usage counting on the region + * + * Memory type region registers control the caching on newer Intel and + * non Intel processors. This function allows drivers to request an + * MTRR is added. The details and hardware specifics of each processor's + * implementation are hidden from the caller, but nevertheless the + * caller should expect to need to provide a power of two size on an + * equivalent power of two boundary. + * + * If the region cannot be added either because all regions are in use + * or the CPU cannot support it a negative value is returned. On success + * the register number for this entry is returned, but should be treated + * as a cookie only. + * + * On a multiprocessor machine the changes are made to all processors. + * This is required on x86 by the Intel processors. + * + * The available types are + * + * %MTRR_TYPE_UNCACHABLE - No caching + * + * %MTRR_TYPE_WRBACK - Write data back in bursts whenever + * + * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts + * + * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes + * + * BUGS: Needs a quiet flag for the cases where drivers do not mind + * failures and do not wish system log messages to be sent. + */ +int mtrr_add_page(unsigned long base, unsigned long size, + unsigned int type, bool increment) +{ + unsigned long lbase, lsize; + int i, replace, error; + mtrr_type ltype; + + if (!mtrr_enabled()) + return -ENXIO; + + error = mtrr_if->validate_add_page(base, size, type); + if (error) + return error; + + if (type >= MTRR_NUM_TYPES) { + pr_warn("type: %u invalid\n", type); + return -EINVAL; + } + + /* If the type is WC, check that this processor supports it */ + if ((type == MTRR_TYPE_WRCOMB) && !have_wrcomb()) { + pr_warn("your processor doesn't support write-combining\n"); + return -ENOSYS; + } + + if (!size) { + pr_warn("zero sized request\n"); + return -EINVAL; + } + + if ((base | (base + size - 1)) >> + (boot_cpu_data.x86_phys_bits - PAGE_SHIFT)) { + pr_warn("base or size exceeds the MTRR width\n"); + return -EINVAL; + } + + error = -EINVAL; + replace = -1; + + /* No CPU hotplug when we change MTRR entries */ + cpus_read_lock(); + + /* Search for existing MTRR */ + mutex_lock(&mtrr_mutex); + for (i = 0; i < num_var_ranges; ++i) { + mtrr_if->get(i, &lbase, &lsize, <ype); + if (!lsize || base > lbase + lsize - 1 || + base + size - 1 < lbase) + continue; + /* + * At this point we know there is some kind of + * overlap/enclosure + */ + if (base < lbase || base + size - 1 > lbase + lsize - 1) { + if (base <= lbase && + base + size - 1 >= lbase + lsize - 1) { + /* New region encloses an existing region */ + if (type == ltype) { + replace = replace == -1 ? i : -2; + continue; + } else if (types_compatible(type, ltype)) + continue; + } + pr_warn("0x%lx000,0x%lx000 overlaps existing 0x%lx000,0x%lx000\n", base, size, lbase, + lsize); + goto out; + } + /* New region is enclosed by an existing region */ + if (ltype != type) { + if (types_compatible(type, ltype)) + continue; + pr_warn("type mismatch for %lx000,%lx000 old: %s new: %s\n", + base, size, mtrr_attrib_to_str(ltype), + mtrr_attrib_to_str(type)); + goto out; + } + if (increment) + ++mtrr_usage_table[i]; + error = i; + goto out; + } + /* Search for an empty MTRR */ + i = mtrr_if->get_free_region(base, size, replace); + if (i >= 0) { + set_mtrr(i, base, size, type); + if (likely(replace < 0)) { + mtrr_usage_table[i] = 1; + } else { + mtrr_usage_table[i] = mtrr_usage_table[replace]; + if (increment) + mtrr_usage_table[i]++; + if (unlikely(replace != i)) { + set_mtrr(replace, 0, 0, 0); + mtrr_usage_table[replace] = 0; + } + } + } else { + pr_info("no more MTRRs available\n"); + } + error = i; + out: + mutex_unlock(&mtrr_mutex); + cpus_read_unlock(); + return error; +} + +static int mtrr_check(unsigned long base, unsigned long size) +{ + if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) { + pr_warn("size and base must be multiples of 4 kiB\n"); + Dprintk("size: 0x%lx base: 0x%lx\n", size, base); + dump_stack(); + return -1; + } + return 0; +} + +/** + * mtrr_add - Add a memory type region + * @base: Physical base address of region + * @size: Physical size of region + * @type: Type of MTRR desired + * @increment: If this is true do usage counting on the region + * + * Memory type region registers control the caching on newer Intel and + * non Intel processors. This function allows drivers to request an + * MTRR is added. The details and hardware specifics of each processor's + * implementation are hidden from the caller, but nevertheless the + * caller should expect to need to provide a power of two size on an + * equivalent power of two boundary. + * + * If the region cannot be added either because all regions are in use + * or the CPU cannot support it a negative value is returned. On success + * the register number for this entry is returned, but should be treated + * as a cookie only. + * + * On a multiprocessor machine the changes are made to all processors. + * This is required on x86 by the Intel processors. + * + * The available types are + * + * %MTRR_TYPE_UNCACHABLE - No caching + * + * %MTRR_TYPE_WRBACK - Write data back in bursts whenever + * + * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts + * + * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes + * + * BUGS: Needs a quiet flag for the cases where drivers do not mind + * failures and do not wish system log messages to be sent. + */ +int mtrr_add(unsigned long base, unsigned long size, unsigned int type, + bool increment) +{ + if (!mtrr_enabled()) + return -ENODEV; + if (mtrr_check(base, size)) + return -EINVAL; + return mtrr_add_page(base >> PAGE_SHIFT, size >> PAGE_SHIFT, type, + increment); +} + +/** + * mtrr_del_page - delete a memory type region + * @reg: Register returned by mtrr_add + * @base: Physical base address + * @size: Size of region + * + * If register is supplied then base and size are ignored. This is + * how drivers should call it. + * + * Releases an MTRR region. If the usage count drops to zero the + * register is freed and the region returns to default state. + * On success the register is returned, on failure a negative error + * code. + */ +int mtrr_del_page(int reg, unsigned long base, unsigned long size) +{ + int i, max; + mtrr_type ltype; + unsigned long lbase, lsize; + int error = -EINVAL; + + if (!mtrr_enabled()) + return -ENODEV; + + max = num_var_ranges; + /* No CPU hotplug when we change MTRR entries */ + cpus_read_lock(); + mutex_lock(&mtrr_mutex); + if (reg < 0) { + /* Search for existing MTRR */ + for (i = 0; i < max; ++i) { + mtrr_if->get(i, &lbase, &lsize, <ype); + if (lbase == base && lsize == size) { + reg = i; + break; + } + } + if (reg < 0) { + Dprintk("no MTRR for %lx000,%lx000 found\n", base, size); + goto out; + } + } + if (reg >= max) { + pr_warn("register: %d too big\n", reg); + goto out; + } + mtrr_if->get(reg, &lbase, &lsize, <ype); + if (lsize < 1) { + pr_warn("MTRR %d not used\n", reg); + goto out; + } + if (mtrr_usage_table[reg] < 1) { + pr_warn("reg: %d has count=0\n", reg); + goto out; + } + if (--mtrr_usage_table[reg] < 1) + set_mtrr(reg, 0, 0, 0); + error = reg; + out: + mutex_unlock(&mtrr_mutex); + cpus_read_unlock(); + return error; +} + +/** + * mtrr_del - delete a memory type region + * @reg: Register returned by mtrr_add + * @base: Physical base address + * @size: Size of region + * + * If register is supplied then base and size are ignored. This is + * how drivers should call it. + * + * Releases an MTRR region. If the usage count drops to zero the + * register is freed and the region returns to default state. + * On success the register is returned, on failure a negative error + * code. + */ +int mtrr_del(int reg, unsigned long base, unsigned long size) +{ + if (!mtrr_enabled()) + return -ENODEV; + if (mtrr_check(base, size)) + return -EINVAL; + return mtrr_del_page(reg, base >> PAGE_SHIFT, size >> PAGE_SHIFT); +} + +/** + * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable + * @base: Physical base address + * @size: Size of region + * + * If PAT is available, this does nothing. If PAT is unavailable, it + * attempts to add a WC MTRR covering size bytes starting at base and + * logs an error if this fails. + * + * The called should provide a power of two size on an equivalent + * power of two boundary. + * + * Drivers must store the return value to pass to mtrr_del_wc_if_needed, + * but drivers should not try to interpret that return value. + */ +int arch_phys_wc_add(unsigned long base, unsigned long size) +{ + int ret; + + if (pat_enabled() || !mtrr_enabled()) + return 0; /* Success! (We don't need to do anything.) */ + + ret = mtrr_add(base, size, MTRR_TYPE_WRCOMB, true); + if (ret < 0) { + pr_warn("Failed to add WC MTRR for [%p-%p]; performance may suffer.", + (void *)base, (void *)(base + size - 1)); + return ret; + } + return ret + MTRR_TO_PHYS_WC_OFFSET; +} +EXPORT_SYMBOL(arch_phys_wc_add); + +/* + * arch_phys_wc_del - undoes arch_phys_wc_add + * @handle: Return value from arch_phys_wc_add + * + * This cleans up after mtrr_add_wc_if_needed. + * + * The API guarantees that mtrr_del_wc_if_needed(error code) and + * mtrr_del_wc_if_needed(0) do nothing. + */ +void arch_phys_wc_del(int handle) +{ + if (handle >= 1) { + WARN_ON(handle < MTRR_TO_PHYS_WC_OFFSET); + mtrr_del(handle - MTRR_TO_PHYS_WC_OFFSET, 0, 0); + } +} +EXPORT_SYMBOL(arch_phys_wc_del); + +/* + * arch_phys_wc_index - translates arch_phys_wc_add's return value + * @handle: Return value from arch_phys_wc_add + * + * This will turn the return value from arch_phys_wc_add into an mtrr + * index suitable for debugging. + * + * Note: There is no legitimate use for this function, except possibly + * in printk line. Alas there is an illegitimate use in some ancient + * drm ioctls. + */ +int arch_phys_wc_index(int handle) +{ + if (handle < MTRR_TO_PHYS_WC_OFFSET) + return -1; + else + return handle - MTRR_TO_PHYS_WC_OFFSET; +} +EXPORT_SYMBOL_GPL(arch_phys_wc_index); + +int __initdata changed_by_mtrr_cleanup; + +/** + * mtrr_bp_init - initialize MTRRs on the boot CPU + * + * This needs to be called early; before any of the other CPUs are + * initialized (i.e. before smp_init()). + */ +void __init mtrr_bp_init(void) +{ + bool generic_mtrrs = cpu_feature_enabled(X86_FEATURE_MTRR); + const char *why = "(not available)"; + unsigned long config, dummy; + + phys_hi_rsvd = GENMASK(31, boot_cpu_data.x86_phys_bits - 32); + + if (!generic_mtrrs && mtrr_state.enabled) { + /* + * Software overwrite of MTRR state, only for generic case. + * Note that X86_FEATURE_MTRR has been reset in this case. + */ + init_table(); + mtrr_build_map(); + pr_info("MTRRs set to read-only\n"); + + return; + } + + if (generic_mtrrs) + mtrr_if = &generic_mtrr_ops; + else + mtrr_set_if(); + + if (mtrr_enabled()) { + /* Get the number of variable MTRR ranges. */ + if (mtrr_if == &generic_mtrr_ops) + rdmsr(MSR_MTRRcap, config, dummy); + else + config = mtrr_if->var_regs; + num_var_ranges = config & MTRR_CAP_VCNT; + + init_table(); + if (mtrr_if == &generic_mtrr_ops) { + /* BIOS may override */ + if (get_mtrr_state()) { + memory_caching_control |= CACHE_MTRR; + changed_by_mtrr_cleanup = mtrr_cleanup(); + mtrr_build_map(); + } else { + mtrr_if = NULL; + why = "by BIOS"; + } + } + } + + if (!mtrr_enabled()) + pr_info("MTRRs disabled %s\n", why); +} + +/** + * mtrr_save_state - Save current fixed-range MTRR state of the first + * cpu in cpu_online_mask. + */ +void mtrr_save_state(void) +{ + int first_cpu; + + if (!mtrr_enabled()) + return; + + first_cpu = cpumask_first(cpu_online_mask); + smp_call_function_single(first_cpu, mtrr_save_fixed_ranges, NULL, 1); +} + +static int __init mtrr_init_finalize(void) +{ + /* + * Map might exist if mtrr_overwrite_state() has been called or if + * mtrr_enabled() returns true. + */ + mtrr_copy_map(); + + if (!mtrr_enabled()) + return 0; + + if (memory_caching_control & CACHE_MTRR) { + if (!changed_by_mtrr_cleanup) + mtrr_state_warn(); + return 0; + } + + mtrr_register_syscore(); + + return 0; +} +subsys_initcall(mtrr_init_finalize); diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h new file mode 100644 index 0000000000..5655f253d9 --- /dev/null +++ b/arch/x86/kernel/cpu/mtrr/mtrr.h @@ -0,0 +1,94 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * local MTRR defines. + */ + +#include <linux/types.h> +#include <linux/stddef.h> + +#define MTRR_CHANGE_MASK_FIXED 0x01 +#define MTRR_CHANGE_MASK_VARIABLE 0x02 +#define MTRR_CHANGE_MASK_DEFTYPE 0x04 + +extern bool mtrr_debug; +#define Dprintk(x...) do { if (mtrr_debug) pr_info(x); } while (0) + +extern unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES]; + +struct mtrr_ops { + u32 var_regs; + void (*set)(unsigned int reg, unsigned long base, + unsigned long size, mtrr_type type); + void (*get)(unsigned int reg, unsigned long *base, + unsigned long *size, mtrr_type *type); + int (*get_free_region)(unsigned long base, unsigned long size, + int replace_reg); + int (*validate_add_page)(unsigned long base, unsigned long size, + unsigned int type); + int (*have_wrcomb)(void); +}; + +extern int generic_get_free_region(unsigned long base, unsigned long size, + int replace_reg); +extern int generic_validate_add_page(unsigned long base, unsigned long size, + unsigned int type); + +extern const struct mtrr_ops generic_mtrr_ops; + +extern int positive_have_wrcomb(void); + +/* library functions for processor-specific routines */ +struct set_mtrr_context { + unsigned long flags; + unsigned long cr4val; + u32 deftype_lo; + u32 deftype_hi; + u32 ccr3; +}; + +void set_mtrr_done(struct set_mtrr_context *ctxt); +void set_mtrr_cache_disable(struct set_mtrr_context *ctxt); +void set_mtrr_prepare_save(struct set_mtrr_context *ctxt); + +void fill_mtrr_var_range(unsigned int index, + u32 base_lo, u32 base_hi, u32 mask_lo, u32 mask_hi); +bool get_mtrr_state(void); + +extern const struct mtrr_ops *mtrr_if; +extern struct mutex mtrr_mutex; + +extern unsigned int num_var_ranges; +extern u64 mtrr_tom2; +extern struct mtrr_state_type mtrr_state; +extern u32 phys_hi_rsvd; + +void mtrr_state_warn(void); +const char *mtrr_attrib_to_str(int x); +void mtrr_wrmsr(unsigned, unsigned, unsigned); +#ifdef CONFIG_X86_32 +void mtrr_set_if(void); +void mtrr_register_syscore(void); +#else +static inline void mtrr_set_if(void) { } +static inline void mtrr_register_syscore(void) { } +#endif +void mtrr_build_map(void); +void mtrr_copy_map(void); + +/* CPU specific mtrr_ops vectors. */ +extern const struct mtrr_ops amd_mtrr_ops; +extern const struct mtrr_ops cyrix_mtrr_ops; +extern const struct mtrr_ops centaur_mtrr_ops; + +extern int changed_by_mtrr_cleanup; +extern int mtrr_cleanup(void); + +/* + * Must be used by code which uses mtrr_if to call platform-specific + * MTRR manipulation functions. + */ +static inline bool mtrr_enabled(void) +{ + return !!mtrr_if; +} +void generic_rebuild_map(void); |