diff options
Diffstat (limited to 'arch/x86/kernel/cpu/mtrr/main.c')
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/main.c | 455 |
1 files changed, 242 insertions, 213 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 8fc248b5aea..7af0f88a416 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -25,43 +25,48 @@ 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: + 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/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/cpu.h> -#include <linux/mutex.h> -#include <linux/sort.h> +#include <asm/processor.h> #include <asm/e820.h> #include <asm/mtrr.h> -#include <asm/uaccess.h> -#include <asm/processor.h> #include <asm/msr.h> -#include <asm/kvm_para.h> + #include "mtrr.h" -u32 num_var_ranges = 0; +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 struct mtrr_ops * mtrr_ops[X86_VENDOR_NUM] = {}; +static struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM]; -struct mtrr_ops * mtrr_if = NULL; +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(struct mtrr_ops * ops) +void set_mtrr_ops(struct mtrr_ops *ops) { if (ops->vendor && ops->vendor < X86_VENDOR_NUM) mtrr_ops[ops->vendor] = ops; @@ -72,30 +77,36 @@ static int have_wrcomb(void) { struct pci_dev *dev; u8 rev; - - if ((dev = pci_get_class(PCI_CLASS_BRIDGE_HOST << 8, NULL)) != NULL) { - /* ServerWorks LE chipsets < rev 6 have problems with write-combining - Don't allow it and leave room for other chipsets to be tagged */ + + 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) { pci_read_config_byte(dev, PCI_CLASS_REVISION, &rev); if (rev <= 5) { - printk(KERN_INFO "mtrr: Serverworks LE rev < 6 detected. Write-combining disabled.\n"); + 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 */ + /* + * 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) { - printk(KERN_INFO "mtrr: Intel 450NX MMC detected. Write-combining disabled.\n"); + 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); + } + return mtrr_if->have_wrcomb ? mtrr_if->have_wrcomb() : 0; } /* This function returns the number of variable MTRRs */ @@ -103,12 +114,13 @@ static void __init set_num_var_ranges(void) { unsigned long config = 0, dummy; - if (use_intel()) { + if (use_intel()) rdmsr(MSR_MTRRcap, config, dummy); - } else if (is_cpu(AMD)) + else if (is_cpu(AMD)) config = 2; else if (is_cpu(CYRIX) || is_cpu(CENTAUR)) config = 8; + num_var_ranges = config & 0xff; } @@ -130,10 +142,12 @@ struct set_mtrr_data { mtrr_type smp_type; }; +/** + * ipi_handler - Synchronisation handler. Executed by "other" CPUs. + * + * Returns nothing. + */ static void ipi_handler(void *info) -/* [SUMMARY] Synchronisation handler. Executed by "other" CPUs. - [RETURNS] Nothing. -*/ { #ifdef CONFIG_SMP struct set_mtrr_data *data = info; @@ -142,18 +156,19 @@ static void ipi_handler(void *info) local_irq_save(flags); atomic_dec(&data->count); - while(!atomic_read(&data->gate)) + while (!atomic_read(&data->gate)) cpu_relax(); /* The master has cleared me to execute */ - if (data->smp_reg != ~0U) - mtrr_if->set(data->smp_reg, data->smp_base, + if (data->smp_reg != ~0U) { + mtrr_if->set(data->smp_reg, data->smp_base, data->smp_size, data->smp_type); - else + } else { mtrr_if->set_all(); + } atomic_dec(&data->count); - while(atomic_read(&data->gate)) + while (atomic_read(&data->gate)) cpu_relax(); atomic_dec(&data->count); @@ -161,7 +176,8 @@ static void ipi_handler(void *info) #endif } -static inline int types_compatible(mtrr_type type1, mtrr_type type2) { +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) || @@ -176,10 +192,10 @@ static inline int types_compatible(mtrr_type type1, mtrr_type type2) { * @type: mtrr type * * This is kinda tricky, but fortunately, Intel spelled it out for us cleanly: - * + * * 1. Send IPI to do the following: * 2. Disable Interrupts - * 3. Wait for all procs to do so + * 3. Wait for all procs to do so * 4. Enter no-fill cache mode * 5. Flush caches * 6. Clear PGE bit @@ -189,26 +205,27 @@ static inline int types_compatible(mtrr_type type1, mtrr_type type2) { * 10. Enable all range registers * 11. Flush all TLBs and caches again * 12. Enter normal cache mode and reenable caching - * 13. Set PGE + * 13. Set PGE * 14. Wait for buddies to catch up * 15. Enable interrupts. - * + * * What does that mean for us? Well, first we set data.count to the number * of CPUs. As each CPU disables interrupts, it'll decrement it once. We wait * until it hits 0 and proceed. We set the data.gate flag and reset data.count. - * Meanwhile, they are waiting for that flag to be set. Once it's set, each - * CPU goes through the transition of updating MTRRs. The CPU vendors may each do it - * differently, so we call mtrr_if->set() callback and let them take care of it. - * When they're done, they again decrement data->count and wait for data.gate to - * be reset. - * When we finish, we wait for data.count to hit 0 and toggle the data.gate flag. + * Meanwhile, they are waiting for that flag to be set. Once it's set, each + * CPU goes through the transition of updating MTRRs. + * The CPU vendors may each do it differently, + * so we call mtrr_if->set() callback and let them take care of it. + * When they're done, they again decrement data->count and wait for data.gate + * to be reset. + * When we finish, we wait for data.count to hit 0 and toggle the data.gate flag * Everyone then enables interrupts and we all continue on. * * 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) +static void +set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type type) { struct set_mtrr_data data; unsigned long flags; @@ -218,121 +235,122 @@ static void set_mtrr(unsigned int reg, unsigned long base, data.smp_size = size; data.smp_type = type; atomic_set(&data.count, num_booting_cpus() - 1); - /* make sure data.count is visible before unleashing other CPUs */ + + /* Make sure data.count is visible before unleashing other CPUs */ smp_wmb(); - atomic_set(&data.gate,0); + atomic_set(&data.gate, 0); - /* Start the ball rolling on other CPUs */ + /* Start the ball rolling on other CPUs */ if (smp_call_function(ipi_handler, &data, 0) != 0) panic("mtrr: timed out waiting for other CPUs\n"); local_irq_save(flags); - while(atomic_read(&data.count)) + while (atomic_read(&data.count)) cpu_relax(); - /* ok, reset count and toggle gate */ + /* Ok, reset count and toggle gate */ atomic_set(&data.count, num_booting_cpus() - 1); smp_wmb(); - atomic_set(&data.gate,1); + atomic_set(&data.gate, 1); - /* do our MTRR business */ + /* Do our MTRR business */ - /* HACK! + /* + * HACK! * We use this same function to initialize the mtrrs on boot. * The state of the boot cpu's mtrrs has been saved, and we want - * to replicate across all the APs. + * to replicate across all the APs. * If we're doing that @reg is set to something special... */ - if (reg != ~0U) - mtrr_if->set(reg,base,size,type); + if (reg != ~0U) + mtrr_if->set(reg, base, size, type); - /* wait for the others */ - while(atomic_read(&data.count)) + /* Wait for the others */ + while (atomic_read(&data.count)) cpu_relax(); atomic_set(&data.count, num_booting_cpus() - 1); smp_wmb(); - atomic_set(&data.gate,0); + atomic_set(&data.gate, 0); /* * Wait here for everyone to have seen the gate change * So we're the last ones to touch 'data' */ - while(atomic_read(&data.count)) + while (atomic_read(&data.count)) cpu_relax(); local_irq_restore(flags); } /** - * 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 + * 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. + * 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. + * 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. + * On a multiprocessor machine the changes are made to all processors. + * This is required on x86 by the Intel processors. * - * The available types are + * The available types are * - * %MTRR_TYPE_UNCACHABLE - No caching + * %MTRR_TYPE_UNCACHABLE - No caching * - * %MTRR_TYPE_WRBACK - Write data back in bursts whenever + * %MTRR_TYPE_WRBACK - Write data back in bursts whenever * - * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts + * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts * - * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes + * %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. + * 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, +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; - unsigned long lbase, lsize; if (!mtrr_if) return -ENXIO; - - if ((error = mtrr_if->validate_add_page(base,size,type))) + + error = mtrr_if->validate_add_page(base, size, type); + if (error) return error; if (type >= MTRR_NUM_TYPES) { - printk(KERN_WARNING "mtrr: type: %u invalid\n", type); + pr_warning("mtrr: type: %u invalid\n", type); return -EINVAL; } - /* If the type is WC, check that this processor supports it */ + /* If the type is WC, check that this processor supports it */ if ((type == MTRR_TYPE_WRCOMB) && !have_wrcomb()) { - printk(KERN_WARNING - "mtrr: your processor doesn't support write-combining\n"); + pr_warning("mtrr: your processor doesn't support write-combining\n"); return -ENOSYS; } if (!size) { - printk(KERN_WARNING "mtrr: zero sized request\n"); + pr_warning("mtrr: zero sized request\n"); return -EINVAL; } if (base & size_or_mask || size & size_or_mask) { - printk(KERN_WARNING "mtrr: base or size exceeds the MTRR width\n"); + pr_warning("mtrr: base or size exceeds the MTRR width\n"); return -EINVAL; } @@ -341,36 +359,40 @@ int mtrr_add_page(unsigned long base, unsigned long size, /* No CPU hotplug when we change MTRR entries */ get_online_cpus(); - /* Search for existing MTRR */ + + /* 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) + if (!lsize || base > lbase + lsize - 1 || + base + size - 1 < lbase) continue; - /* At this point we know there is some kind of overlap/enclosure */ + /* + * 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) { + 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)) + } else if (types_compatible(type, ltype)) continue; } - printk(KERN_WARNING - "mtrr: 0x%lx000,0x%lx000 overlaps existing" - " 0x%lx000,0x%lx000\n", base, size, lbase, - lsize); + 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 */ + /* New region is enclosed by an existing region */ if (ltype != type) { if (types_compatible(type, ltype)) continue; - printk (KERN_WARNING "mtrr: type mismatch for %lx000,%lx000 old: %s new: %s\n", - base, size, mtrr_attrib_to_str(ltype), - mtrr_attrib_to_str(type)); + 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) @@ -378,7 +400,7 @@ int mtrr_add_page(unsigned long base, unsigned long size, error = i; goto out; } - /* Search for an empty MTRR */ + /* Search for an empty MTRR */ i = mtrr_if->get_free_region(base, size, replace); if (i >= 0) { set_mtrr(i, base, size, type); @@ -393,8 +415,9 @@ int mtrr_add_page(unsigned long base, unsigned long size, mtrr_usage_table[replace] = 0; } } - } else - printk(KERN_INFO "mtrr: no more MTRRs available\n"); + } else { + pr_info("mtrr: no more MTRRs available\n"); + } error = i; out: mutex_unlock(&mtrr_mutex); @@ -405,10 +428,8 @@ int mtrr_add_page(unsigned long base, unsigned long size, static int mtrr_check(unsigned long base, unsigned long size) { if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) { - printk(KERN_WARNING - "mtrr: size and base must be multiples of 4 kiB\n"); - printk(KERN_DEBUG - "mtrr: size: 0x%lx base: 0x%lx\n", size, base); + 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; } @@ -416,66 +437,64 @@ static int mtrr_check(unsigned long base, unsigned long size) } /** - * 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 + * 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. + * 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. + * 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. + * On a multiprocessor machine the changes are made to all processors. + * This is required on x86 by the Intel processors. * - * The available types are + * The available types are * - * %MTRR_TYPE_UNCACHABLE - No caching + * %MTRR_TYPE_UNCACHABLE - No caching * - * %MTRR_TYPE_WRBACK - Write data back in bursts whenever + * %MTRR_TYPE_WRBACK - Write data back in bursts whenever * - * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts + * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts * - * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes + * %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. + * 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) +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 + * 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. + * 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. + * 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; @@ -500,22 +519,22 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size) } } if (reg < 0) { - printk(KERN_DEBUG "mtrr: no MTRR for %lx000,%lx000 found\n", base, - size); + pr_debug("mtrr: no MTRR for %lx000,%lx000 found\n", + base, size); goto out; } } if (reg >= max) { - printk(KERN_WARNING "mtrr: register: %d too big\n", reg); + pr_warning("mtrr: register: %d too big\n", reg); goto out; } mtrr_if->get(reg, &lbase, &lsize, <ype); if (lsize < 1) { - printk(KERN_WARNING "mtrr: MTRR %d not used\n", reg); + pr_warning("mtrr: MTRR %d not used\n", reg); goto out; } if (mtrr_usage_table[reg] < 1) { - printk(KERN_WARNING "mtrr: reg: %d has count=0\n", reg); + pr_warning("mtrr: reg: %d has count=0\n", reg); goto out; } if (--mtrr_usage_table[reg] < 1) @@ -526,33 +545,31 @@ int mtrr_del_page(int reg, unsigned long base, unsigned long size) 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 + * 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. + * 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. + * 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) +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_add); EXPORT_SYMBOL(mtrr_del); -/* HACK ALERT! +/* + * HACK ALERT! * These should be called implicitly, but we can't yet until all the initcall * stuff is done... */ @@ -576,29 +593,28 @@ struct mtrr_value { static struct mtrr_value mtrr_value[MTRR_MAX_VAR_RANGES]; -static int mtrr_save(struct sys_device * sysdev, pm_message_t state) +static int mtrr_save(struct sys_device *sysdev, pm_message_t state) { 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); + mtrr_if->get(i, &mtrr_value[i].lbase, + &mtrr_value[i].lsize, + &mtrr_value[i].ltype); } return 0; } -static int mtrr_restore(struct sys_device * sysdev) +static int mtrr_restore(struct sys_device *sysdev) { 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); + if (mtrr_value[i].lsize) { + set_mtrr(i, mtrr_value[i].lbase, + mtrr_value[i].lsize, + mtrr_value[i].ltype); + } } return 0; } @@ -615,26 +631,29 @@ 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 + * 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 = 0xff000000; /* 36 bits */ + size_or_mask = 0xff000000; /* 36 bits */ size_and_mask = 0x00f00000; phys_addr = 36; - /* This is an AMD specific MSR, but we assume(hope?) that - Intel will implement it to when they extend the address - bus of the Xeon. */ + /* + * This is an AMD specific MSR, but we assume(hope?) that + * Intel will implement it to 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 */ @@ -649,9 +668,11 @@ void __init mtrr_bp_init(void) 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 = 0xfff00000; /* 32 bits */ + /* + * VIA C* family have Intel style MTRRs, + * but don't support PAE + */ + size_or_mask = 0xfff00000; /* 32 bits */ size_and_mask = 0; phys_addr = 32; } @@ -694,7 +715,6 @@ void __init mtrr_bp_init(void) changed_by_mtrr_cleanup = 1; mtrr_if->set_all(); } - } } } @@ -706,12 +726,17 @@ void mtrr_ap_init(void) if (!mtrr_if || !use_intel()) 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 + * 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 */ local_irq_save(flags); @@ -732,19 +757,23 @@ static int __init mtrr_init_finialize(void) { if (!mtrr_if) return 0; + if (use_intel()) { if (!changed_by_mtrr_cleanup) mtrr_state_warn(); - } else { - /* The CPUs haven't MTRR and seem 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. - */ - sysdev_driver_register(&cpu_sysdev_class, - &mtrr_sysdev_driver); + 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. + */ + sysdev_driver_register(&cpu_sysdev_class, &mtrr_sysdev_driver); + return 0; } subsys_initcall(mtrr_init_finialize); |