--- /dev/null
+/* 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).
+*/
+
+#define DEBUG
+
+#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/module.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 <asm/processor.h>
+#include <asm/e820.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+#include <asm/pat.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];
+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];
+
+const struct mtrr_ops *mtrr_if;
+
+static void set_mtrr(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type);
+
+void 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)
+{
+ 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("mtrr: 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("mtrr: 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;
+}
+
+/* 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))
+ 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;
+
+ 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;
+
+ /*
+ * 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();
+ }
+ 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(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);
+}
+
+/**
+ * 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_if)
+ return -ENXIO;
+
+ error = mtrr_if->validate_add_page(base, size, type);
+ if (error)
+ return error;
+
+ if (type >= MTRR_NUM_TYPES) {
+ pr_warning("mtrr: 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_warning("mtrr: your processor doesn't support write-combining\n");
+ return -ENOSYS;
+ }
+
+ if (!size) {
+ pr_warning("mtrr: zero sized request\n");
+ return -EINVAL;
+ }
+
+ if ((base | (base + size - 1)) >>
+ (boot_cpu_data.x86_phys_bits - PAGE_SHIFT)) {
+ pr_warning("mtrr: base or size exceeds the MTRR width\n");
+ return -EINVAL;
+ }
+
+ error = -EINVAL;
+ replace = -1;
+
+ /* No CPU hotplug when we change MTRR entries */
+ get_online_cpus();
+
+ /* 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_warning("mtrr: 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_warning("mtrr: 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("mtrr: no more MTRRs available\n");
+ }
+ error = i;
+ out:
+ mutex_unlock(&mtrr_mutex);
+ put_online_cpus();
+ return error;
+}
+
+static int mtrr_check(unsigned long base, unsigned long size)
+{
+ if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) {
+ pr_warning("mtrr: size and base must be multiples of 4 kiB\n");
+ pr_debug("mtrr: 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_check(base, size))
+ return -EINVAL;
+ return mtrr_add_page(base >> PAGE_SHIFT, size >> PAGE_SHIFT, type,
+ increment);
+}
+EXPORT_SYMBOL(mtrr_add);
+
+/**
+ * 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_if)
+ return -ENXIO;
+
+ max = num_var_ranges;
+ /* No CPU hotplug when we change MTRR entries */
+ get_online_cpus();
+ 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) {
+ pr_debug("mtrr: no MTRR for %lx000,%lx000 found\n",
+ base, size);
+ goto out;
+ }
+ }
+ if (reg >= max) {
+ pr_warning("mtrr: register: %d too big\n", reg);
+ goto out;
+ }
+ mtrr_if->get(reg, &lbase, &lsize, <ype);
+ if (lsize < 1) {
+ pr_warning("mtrr: MTRR %d not used\n", reg);
+ goto out;
+ }
+ if (mtrr_usage_table[reg] < 1) {
+ pr_warning("mtrr: 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);
+ put_online_cpus();
+ 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_check(base, size))
+ return -EINVAL;
+ return mtrr_del_page(reg, base >> PAGE_SHIFT, size >> PAGE_SHIFT);
+}
+EXPORT_SYMBOL(mtrr_del);
+
+/**
+ * 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.
+ *
+ * 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)
+ 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);
+
+/*
+ * phys_wc_to_mtrr_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 phys_wc_to_mtrr_index(int handle)
+{
+ if (handle < MTRR_TO_PHYS_WC_OFFSET)
+ return -1;
+ else
+ return handle - MTRR_TO_PHYS_WC_OFFSET;
+}
+EXPORT_SYMBOL_GPL(phys_wc_to_mtrr_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
+ *
+ * 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();
+
+ phys_addr = 32;
+
+ if (cpu_has_mtrr) {
+ mtrr_if = &generic_mtrr_ops;
+ size_or_mask = SIZE_OR_MASK_BITS(36);
+ size_and_mask = 0x00f00000;
+ phys_addr = 36;
+
+ /*
+ * 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.
+ */
+ 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_mask == 0x3 ||
+ boot_cpu_data.x86_mask == 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;
+ }
+ }
+
+ if (mtrr_if) {
+ set_num_var_ranges();
+ init_table();
+ if (use_intel()) {
+ get_mtrr_state();
+
+ if (mtrr_cleanup(phys_addr)) {
+ changed_by_mtrr_cleanup = 1;
+ mtrr_if->set_all();
+ }
+ }
+ }
+}
+
+void mtrr_ap_init(void)
+{
+ 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 earily 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);
+}
+
+/**
+ * Save current fixed-range MTRR state of the first cpu in cpu_online_mask.
+ */
+void mtrr_save_state(void)
+{
+ int first_cpu;
+
+ get_online_cpus();
+ first_cpu = cpumask_first(cpu_online_mask);
+ smp_call_function_single(first_cpu, mtrr_save_fixed_ranges, NULL, 1);
+ put_online_cpus();
+}
+
+void set_mtrr_aps_delayed_init(void)
+{
+ if (!use_intel())
+ return;
+
+ mtrr_aps_delayed_init = true;
+}
+
+/*
+ * Delayed MTRR initialization for all AP's
+ */
+void mtrr_aps_init(void)
+{
+ if (!use_intel())
+ 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.
+ */
+ 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())
+ return;
+
+ mtrr_if->set_all();
+}
+
+static int __init mtrr_init_finialize(void)
+{
+ if (!mtrr_if)
+ return 0;
+
+ if (use_intel()) {
+ 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);
+
+ return 0;
+}
+subsys_initcall(mtrr_init_finialize);
Code Review / kvmfornfv.git / blobdiff