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-rw-r--r--arch/x86/kernel/cpu/mtrr/mtrr.c386
1 files changed, 66 insertions, 320 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c
index a76694bffe86..4b3d492afe17 100644
--- a/arch/x86/kernel/cpu/mtrr/mtrr.c
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.c
@@ -1,22 +1,9 @@
+// SPDX-License-Identifier: LGPL-2.0+
/* 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.
@@ -46,6 +33,7 @@
#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>
@@ -54,36 +42,22 @@
#include "mtrr.h"
+static_assert(X86_MEMTYPE_UC == MTRR_TYPE_UNCACHABLE);
+static_assert(X86_MEMTYPE_WC == MTRR_TYPE_WRCOMB);
+static_assert(X86_MEMTYPE_WT == MTRR_TYPE_WRTHROUGH);
+static_assert(X86_MEMTYPE_WP == MTRR_TYPE_WRPROT);
+static_assert(X86_MEMTYPE_WB == MTRR_TYPE_WRBACK);
+
/* arch_phys_wc_add returns an MTRR register index plus this offset. */
#define MTRR_TO_PHYS_WC_OFFSET 1000
u32 num_var_ranges;
-static bool __mtrr_enabled;
-
-static bool mtrr_enabled(void)
-{
- return __mtrr_enabled;
-}
unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES];
-static DEFINE_MUTEX(mtrr_mutex);
-
-u64 size_or_mask, size_and_mask;
-static bool mtrr_aps_delayed_init;
-
-static const struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM] __ro_after_init;
+DEFINE_MUTEX(mtrr_mutex);
const struct mtrr_ops *mtrr_if;
-static void set_mtrr(unsigned int reg, unsigned long base,
- unsigned long size, mtrr_type type);
-
-void __init set_mtrr_ops(const struct mtrr_ops *ops)
-{
- if (ops->vendor && ops->vendor < X86_VENDOR_NUM)
- mtrr_ops[ops->vendor] = ops;
-}
-
/* Returns non-zero if we have the write-combining memory type */
static int have_wrcomb(void)
{
@@ -118,21 +92,6 @@ static int have_wrcomb(void)
return mtrr_if->have_wrcomb ? mtrr_if->have_wrcomb() : 0;
}
-/* This function returns the number of variable MTRRs */
-static void __init set_num_var_ranges(void)
-{
- unsigned long config = 0, dummy;
-
- if (use_intel())
- rdmsr(MSR_MTRRcap, config, dummy);
- else if (is_cpu(AMD) || is_cpu(HYGON))
- config = 2;
- else if (is_cpu(CYRIX) || is_cpu(CENTAUR))
- config = 8;
-
- num_var_ranges = config & 0xff;
-}
-
static void __init init_table(void)
{
int i, max;
@@ -160,25 +119,8 @@ static int mtrr_rendezvous_handler(void *info)
{
struct set_mtrr_data *data = info;
- /*
- * We use this same function to initialize the mtrrs during boot,
- * resume, runtime cpu online and on an explicit request to set a
- * specific MTRR.
- *
- * During boot or suspend, the state of the boot cpu's mtrrs has been
- * saved, and we want to replicate that across all the cpus that come
- * online (either at the end of boot or resume or during a runtime cpu
- * online). If we're doing that, @reg is set to something special and on
- * all the cpu's we do mtrr_if->set_all() (On the logical cpu that
- * started the boot/resume sequence, this might be a duplicate
- * set_all()).
- */
- if (data->smp_reg != ~0U) {
- mtrr_if->set(data->smp_reg, data->smp_base,
- data->smp_size, data->smp_type);
- } else if (mtrr_aps_delayed_init || !cpu_online(smp_processor_id())) {
- mtrr_if->set_all();
- }
+ mtrr_if->set(data->smp_reg, data->smp_base,
+ data->smp_size, data->smp_type);
return 0;
}
@@ -224,20 +166,8 @@ static inline int types_compatible(mtrr_type type1, mtrr_type type2)
* 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(mtrr_rendezvous_handler, &data, cpu_online_mask);
-}
-
-static void set_mtrr_cpuslocked(unsigned int reg, unsigned long base,
- unsigned long size, mtrr_type type)
+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,
@@ -246,19 +176,8 @@ static void set_mtrr_cpuslocked(unsigned int reg, unsigned long base,
};
stop_machine_cpuslocked(mtrr_rendezvous_handler, &data, cpu_online_mask);
-}
-
-static void set_mtrr_from_inactive_cpu(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_from_inactive_cpu(mtrr_rendezvous_handler, &data,
- cpu_callout_mask);
+ generic_rebuild_map();
}
/**
@@ -336,7 +255,7 @@ int mtrr_add_page(unsigned long base, unsigned long size,
replace = -1;
/* No CPU hotplug when we change MTRR entries */
- get_online_cpus();
+ cpus_read_lock();
/* Search for existing MTRR */
mutex_lock(&mtrr_mutex);
@@ -380,7 +299,7 @@ int mtrr_add_page(unsigned long base, unsigned long size,
/* Search for an empty MTRR */
i = mtrr_if->get_free_region(base, size, replace);
if (i >= 0) {
- set_mtrr_cpuslocked(i, base, size, type);
+ set_mtrr(i, base, size, type);
if (likely(replace < 0)) {
mtrr_usage_table[i] = 1;
} else {
@@ -388,7 +307,7 @@ int mtrr_add_page(unsigned long base, unsigned long size,
if (increment)
mtrr_usage_table[i]++;
if (unlikely(replace != i)) {
- set_mtrr_cpuslocked(replace, 0, 0, 0);
+ set_mtrr(replace, 0, 0, 0);
mtrr_usage_table[replace] = 0;
}
}
@@ -398,7 +317,7 @@ int mtrr_add_page(unsigned long base, unsigned long size,
error = i;
out:
mutex_unlock(&mtrr_mutex);
- put_online_cpus();
+ cpus_read_unlock();
return error;
}
@@ -406,7 +325,7 @@ 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");
- pr_debug("size: 0x%lx base: 0x%lx\n", size, base);
+ Dprintk("size: 0x%lx base: 0x%lx\n", size, base);
dump_stack();
return -1;
}
@@ -485,7 +404,7 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size)
max = num_var_ranges;
/* No CPU hotplug when we change MTRR entries */
- get_online_cpus();
+ cpus_read_lock();
mutex_lock(&mtrr_mutex);
if (reg < 0) {
/* Search for existing MTRR */
@@ -497,8 +416,7 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size)
}
}
if (reg < 0) {
- pr_debug("no MTRR for %lx000,%lx000 found\n",
- base, size);
+ Dprintk("no MTRR for %lx000,%lx000 found\n", base, size);
goto out;
}
}
@@ -516,11 +434,11 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size)
goto out;
}
if (--mtrr_usage_table[reg] < 1)
- set_mtrr_cpuslocked(reg, 0, 0, 0);
+ set_mtrr(reg, 0, 0, 0);
error = reg;
out:
mutex_unlock(&mtrr_mutex);
- put_online_cpus();
+ cpus_read_unlock();
return error;
}
@@ -617,195 +535,63 @@ int arch_phys_wc_index(int handle)
}
EXPORT_SYMBOL_GPL(arch_phys_wc_index);
-/*
- * HACK ALERT!
- * These should be called implicitly, but we can't yet until all the initcall
- * stuff is done...
- */
-static void __init init_ifs(void)
-{
-#ifndef CONFIG_X86_64
- amd_init_mtrr();
- cyrix_init_mtrr();
- centaur_init_mtrr();
-#endif
-}
-
-/* The suspend/resume methods are only for CPU without MTRR. CPU using generic
- * MTRR driver doesn't require this
- */
-struct mtrr_value {
- mtrr_type ltype;
- unsigned long lbase;
- unsigned long lsize;
-};
-
-static struct mtrr_value mtrr_value[MTRR_MAX_VAR_RANGES];
-
-static int mtrr_save(void)
-{
- int i;
-
- 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) {
- set_mtrr(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,
-};
-
int __initdata changed_by_mtrr_cleanup;
-#define SIZE_OR_MASK_BITS(n) (~((1ULL << ((n) - PAGE_SHIFT)) - 1))
/**
- * mtrr_bp_init - initialize mtrrs on the boot CPU
+ * 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)
{
- u32 phys_addr;
-
- init_ifs();
+ bool generic_mtrrs = cpu_feature_enabled(X86_FEATURE_MTRR);
+ const char *why = "(not available)";
+ unsigned long config, dummy;
- phys_addr = 32;
-
- if (boot_cpu_has(X86_FEATURE_MTRR)) {
- mtrr_if = &generic_mtrr_ops;
- size_or_mask = SIZE_OR_MASK_BITS(36);
- size_and_mask = 0x00f00000;
- phys_addr = 36;
+ phys_hi_rsvd = GENMASK(31, boot_cpu_data.x86_phys_bits - 32);
+ if (!generic_mtrrs && mtrr_state.enabled) {
/*
- * This is an AMD specific MSR, but we assume(hope?) that
- * Intel will implement it too when they extend the address
- * bus of the Xeon.
+ * Software overwrite of MTRR state, only for generic case.
+ * Note that X86_FEATURE_MTRR has been reset in this case.
*/
- if (cpuid_eax(0x80000000) >= 0x80000008) {
- phys_addr = cpuid_eax(0x80000008) & 0xff;
- /* CPUID workaround for Intel 0F33/0F34 CPU */
- if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
- boot_cpu_data.x86 == 0xF &&
- boot_cpu_data.x86_model == 0x3 &&
- (boot_cpu_data.x86_stepping == 0x3 ||
- boot_cpu_data.x86_stepping == 0x4))
- phys_addr = 36;
-
- size_or_mask = SIZE_OR_MASK_BITS(phys_addr);
- size_and_mask = ~size_or_mask & 0xfffff00000ULL;
- } else if (boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR &&
- boot_cpu_data.x86 == 6) {
- /*
- * VIA C* family have Intel style MTRRs,
- * but don't support PAE
- */
- size_or_mask = SIZE_OR_MASK_BITS(32);
- size_and_mask = 0;
- phys_addr = 32;
- }
- } else {
- switch (boot_cpu_data.x86_vendor) {
- case X86_VENDOR_AMD:
- if (cpu_feature_enabled(X86_FEATURE_K6_MTRR)) {
- /* Pre-Athlon (K6) AMD CPU MTRRs */
- mtrr_if = mtrr_ops[X86_VENDOR_AMD];
- size_or_mask = SIZE_OR_MASK_BITS(32);
- size_and_mask = 0;
- }
- break;
- case X86_VENDOR_CENTAUR:
- if (cpu_feature_enabled(X86_FEATURE_CENTAUR_MCR)) {
- mtrr_if = mtrr_ops[X86_VENDOR_CENTAUR];
- size_or_mask = SIZE_OR_MASK_BITS(32);
- size_and_mask = 0;
- }
- break;
- case X86_VENDOR_CYRIX:
- if (cpu_feature_enabled(X86_FEATURE_CYRIX_ARR)) {
- mtrr_if = mtrr_ops[X86_VENDOR_CYRIX];
- size_or_mask = SIZE_OR_MASK_BITS(32);
- size_and_mask = 0;
- }
- break;
- default:
- break;
- }
+ init_table();
+ mtrr_build_map();
+ pr_info("MTRRs set to read-only\n");
+
+ return;
}
- if (mtrr_if) {
- __mtrr_enabled = true;
- set_num_var_ranges();
- init_table();
- if (use_intel()) {
- /* BIOS may override */
- __mtrr_enabled = get_mtrr_state();
+ if (generic_mtrrs)
+ mtrr_if = &generic_mtrr_ops;
+ else
+ mtrr_set_if();
- if (mtrr_enabled())
- mtrr_bp_pat_init();
+ 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;
- if (mtrr_cleanup(phys_addr)) {
- changed_by_mtrr_cleanup = 1;
- mtrr_if->set_all();
+ 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("Disabled\n");
-
- /*
- * PAT initialization relies on MTRR's rendezvous handler.
- * Skip PAT init until the handler can initialize both
- * features independently.
- */
- pat_disable("MTRRs disabled, skipping PAT initialization too.");
- }
-}
-
-void mtrr_ap_init(void)
-{
if (!mtrr_enabled())
- return;
-
- if (!use_intel() || mtrr_aps_delayed_init)
- return;
-
- /*
- * Ideally we should hold mtrr_mutex here to avoid mtrr entries
- * changed, but this routine will be called in cpu boot time,
- * holding the lock breaks it.
- *
- * This routine is called in two cases:
- *
- * 1. very early time of software resume, when there absolutely
- * isn't mtrr entry changes;
- *
- * 2. cpu hotadd time. We let mtrr_add/del_page hold cpuhotplug
- * lock to prevent mtrr entry changes
- */
- set_mtrr_from_inactive_cpu(~0U, 0, 0, 0);
+ pr_info("MTRRs disabled %s\n", why);
}
/**
@@ -816,72 +602,32 @@ void mtrr_save_state(void)
{
int first_cpu;
- if (!mtrr_enabled())
+ if (!mtrr_enabled() || !mtrr_state.have_fixed)
return;
first_cpu = cpumask_first(cpu_online_mask);
smp_call_function_single(first_cpu, mtrr_save_fixed_ranges, NULL, 1);
}
-void set_mtrr_aps_delayed_init(void)
+static int __init mtrr_init_finalize(void)
{
- if (!mtrr_enabled())
- return;
- if (!use_intel())
- return;
-
- mtrr_aps_delayed_init = true;
-}
-
-/*
- * Delayed MTRR initialization for all AP's
- */
-void mtrr_aps_init(void)
-{
- if (!use_intel() || !mtrr_enabled())
- return;
-
/*
- * Check if someone has requested the delay of AP MTRR initialization,
- * by doing set_mtrr_aps_delayed_init(), prior to this point. If not,
- * then we are done.
+ * Map might exist if guest_force_mtrr_state() has been called or if
+ * mtrr_enabled() returns true.
*/
- if (!mtrr_aps_delayed_init)
- return;
-
- set_mtrr(~0U, 0, 0, 0);
- mtrr_aps_delayed_init = false;
-}
-
-void mtrr_bp_restore(void)
-{
- if (!use_intel() || !mtrr_enabled())
- return;
-
- mtrr_if->set_all();
-}
+ mtrr_copy_map();
-static int __init mtrr_init_finialize(void)
-{
if (!mtrr_enabled())
return 0;
- if (use_intel()) {
+ if (memory_caching_control & CACHE_MTRR) {
if (!changed_by_mtrr_cleanup)
mtrr_state_warn();
return 0;
}
- /*
- * 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);
+ mtrr_register_syscore();
return 0;
}
-subsys_initcall(mtrr_init_finialize);
+subsys_initcall(mtrr_init_finalize);