--- /dev/null
+/*
+ * (c) 2005 Advanced Micro Devices, Inc.
+ * Your use of this code is subject to the terms and conditions of the
+ * GNU general public license version 2. See "COPYING" or
+ * http://www.gnu.org/licenses/gpl.html
+ *
+ * Written by Jacob Shin - AMD, Inc.
+ *
+ * Support : jacob.shin@amd.com
+ *
+ * MC4_MISC0 DRAM ECC Error Threshold available under AMD K8 Rev F.
+ * MC4_MISC0 exists per physical processor.
+ *
+ */
+
+#include <linux/cpu.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kobject.h>
+#include <linux/notifier.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/sysdev.h>
+#include <linux/sysfs.h>
+#include <asm/apic.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
+#include <asm/percpu.h>
+
+#define PFX "mce_threshold: "
+#define VERSION "version 1.00.9"
+#define NR_BANKS 5
+#define THRESHOLD_MAX 0xFFF
+#define INT_TYPE_APIC 0x00020000
+#define MASK_VALID_HI 0x80000000
+#define MASK_LVTOFF_HI 0x00F00000
+#define MASK_COUNT_EN_HI 0x00080000
+#define MASK_INT_TYPE_HI 0x00060000
+#define MASK_OVERFLOW_HI 0x00010000
+#define MASK_ERR_COUNT_HI 0x00000FFF
+#define MASK_OVERFLOW 0x0001000000000000L
+
+struct threshold_bank {
+ unsigned int cpu;
+ u8 bank;
+ u8 interrupt_enable;
+ u16 threshold_limit;
+ struct kobject kobj;
+};
+
+static struct threshold_bank threshold_defaults = {
+ .interrupt_enable = 0,
+ .threshold_limit = THRESHOLD_MAX,
+};
+
+#ifdef CONFIG_SMP
+static unsigned char shared_bank[NR_BANKS] = {
+ 0, 0, 0, 0, 1
+};
+#endif
+
+static DEFINE_PER_CPU(unsigned char, bank_map); /* see which banks are on */
+
+/*
+ * CPU Initialization
+ */
+
+/* must be called with correct cpu affinity */
+static void threshold_restart_bank(struct threshold_bank *b,
+ int reset, u16 old_limit)
+{
+ u32 mci_misc_hi, mci_misc_lo;
+
+ rdmsr(MSR_IA32_MC0_MISC + b->bank * 4, mci_misc_lo, mci_misc_hi);
+
+ if (b->threshold_limit < (mci_misc_hi & THRESHOLD_MAX))
+ reset = 1; /* limit cannot be lower than err count */
+
+ if (reset) { /* reset err count and overflow bit */
+ mci_misc_hi =
+ (mci_misc_hi & ~(MASK_ERR_COUNT_HI | MASK_OVERFLOW_HI)) |
+ (THRESHOLD_MAX - b->threshold_limit);
+ } else if (old_limit) { /* change limit w/o reset */
+ int new_count = (mci_misc_hi & THRESHOLD_MAX) +
+ (old_limit - b->threshold_limit);
+ mci_misc_hi = (mci_misc_hi & ~MASK_ERR_COUNT_HI) |
+ (new_count & THRESHOLD_MAX);
+ }
+
+ b->interrupt_enable ?
+ (mci_misc_hi = (mci_misc_hi & ~MASK_INT_TYPE_HI) | INT_TYPE_APIC) :
+ (mci_misc_hi &= ~MASK_INT_TYPE_HI);
+
+ mci_misc_hi |= MASK_COUNT_EN_HI;
+ wrmsr(MSR_IA32_MC0_MISC + b->bank * 4, mci_misc_lo, mci_misc_hi);
+}
+
+void __cpuinit mce_amd_feature_init(struct cpuinfo_x86 *c)
+{
+ int bank;
+ u32 mci_misc_lo, mci_misc_hi;
+ unsigned int cpu = smp_processor_id();
+
+ for (bank = 0; bank < NR_BANKS; ++bank) {
+ rdmsr(MSR_IA32_MC0_MISC + bank * 4, mci_misc_lo, mci_misc_hi);
+
+ /* !valid, !counter present, bios locked */
+ if (!(mci_misc_hi & MASK_VALID_HI) ||
+ !(mci_misc_hi & MASK_VALID_HI >> 1) ||
+ (mci_misc_hi & MASK_VALID_HI >> 2))
+ continue;
+
+ per_cpu(bank_map, cpu) |= (1 << bank);
+
+#ifdef CONFIG_SMP
+ if (shared_bank[bank] && cpu_core_id[cpu])
+ continue;
+#endif
+
+ setup_threshold_lvt((mci_misc_hi & MASK_LVTOFF_HI) >> 20);
+ threshold_defaults.cpu = cpu;
+ threshold_defaults.bank = bank;
+ threshold_restart_bank(&threshold_defaults, 0, 0);
+ }
+}
+
+/*
+ * APIC Interrupt Handler
+ */
+
+/*
+ * threshold interrupt handler will service THRESHOLD_APIC_VECTOR.
+ * the interrupt goes off when error_count reaches threshold_limit.
+ * the handler will simply log mcelog w/ software defined bank number.
+ */
+asmlinkage void mce_threshold_interrupt(void)
+{
+ int bank;
+ struct mce m;
+
+ ack_APIC_irq();
+ irq_enter();
+
+ memset(&m, 0, sizeof(m));
+ rdtscll(m.tsc);
+ m.cpu = smp_processor_id();
+
+ /* assume first bank caused it */
+ for (bank = 0; bank < NR_BANKS; ++bank) {
+ m.bank = MCE_THRESHOLD_BASE + bank;
+ rdmsrl(MSR_IA32_MC0_MISC + bank * 4, m.misc);
+
+ if (m.misc & MASK_OVERFLOW) {
+ mce_log(&m);
+ goto out;
+ }
+ }
+ out:
+ irq_exit();
+}
+
+/*
+ * Sysfs Interface
+ */
+
+static struct sysdev_class threshold_sysclass = {
+ set_kset_name("threshold"),
+};
+
+static DEFINE_PER_CPU(struct sys_device, device_threshold);
+
+struct threshold_attr {
+ struct attribute attr;
+ ssize_t(*show) (struct threshold_bank *, char *);
+ ssize_t(*store) (struct threshold_bank *, const char *, size_t count);
+};
+
+static DEFINE_PER_CPU(struct threshold_bank *, threshold_banks[NR_BANKS]);
+
+static cpumask_t affinity_set(unsigned int cpu)
+{
+ cpumask_t oldmask = current->cpus_allowed;
+ cpumask_t newmask = CPU_MASK_NONE;
+ cpu_set(cpu, newmask);
+ set_cpus_allowed(current, newmask);
+ return oldmask;
+}
+
+static void affinity_restore(cpumask_t oldmask)
+{
+ set_cpus_allowed(current, oldmask);
+}
+
+#define SHOW_FIELDS(name) \
+ static ssize_t show_ ## name(struct threshold_bank * b, char *buf) \
+ { \
+ return sprintf(buf, "%lx\n", (unsigned long) b->name); \
+ }
+SHOW_FIELDS(interrupt_enable)
+SHOW_FIELDS(threshold_limit)
+
+static ssize_t store_interrupt_enable(struct threshold_bank *b,
+ const char *buf, size_t count)
+{
+ char *end;
+ cpumask_t oldmask;
+ unsigned long new = simple_strtoul(buf, &end, 0);
+ if (end == buf)
+ return -EINVAL;
+ b->interrupt_enable = !!new;
+
+ oldmask = affinity_set(b->cpu);
+ threshold_restart_bank(b, 0, 0);
+ affinity_restore(oldmask);
+
+ return end - buf;
+}
+
+static ssize_t store_threshold_limit(struct threshold_bank *b,
+ const char *buf, size_t count)
+{
+ char *end;
+ cpumask_t oldmask;
+ u16 old;
+ unsigned long new = simple_strtoul(buf, &end, 0);
+ if (end == buf)
+ return -EINVAL;
+ if (new > THRESHOLD_MAX)
+ new = THRESHOLD_MAX;
+ if (new < 1)
+ new = 1;
+ old = b->threshold_limit;
+ b->threshold_limit = new;
+
+ oldmask = affinity_set(b->cpu);
+ threshold_restart_bank(b, 0, old);
+ affinity_restore(oldmask);
+
+ return end - buf;
+}
+
+static ssize_t show_error_count(struct threshold_bank *b, char *buf)
+{
+ u32 high, low;
+ cpumask_t oldmask;
+ oldmask = affinity_set(b->cpu);
+ rdmsr(MSR_IA32_MC0_MISC + b->bank * 4, low, high); /* ignore low 32 */
+ affinity_restore(oldmask);
+ return sprintf(buf, "%x\n",
+ (high & 0xFFF) - (THRESHOLD_MAX - b->threshold_limit));
+}
+
+static ssize_t store_error_count(struct threshold_bank *b,
+ const char *buf, size_t count)
+{
+ cpumask_t oldmask;
+ oldmask = affinity_set(b->cpu);
+ threshold_restart_bank(b, 1, 0);
+ affinity_restore(oldmask);
+ return 1;
+}
+
+#define THRESHOLD_ATTR(_name,_mode,_show,_store) { \
+ .attr = {.name = __stringify(_name), .mode = _mode }, \
+ .show = _show, \
+ .store = _store, \
+};
+
+#define ATTR_FIELDS(name) \
+ static struct threshold_attr name = \
+ THRESHOLD_ATTR(name, 0644, show_## name, store_## name)
+
+ATTR_FIELDS(interrupt_enable);
+ATTR_FIELDS(threshold_limit);
+ATTR_FIELDS(error_count);
+
+static struct attribute *default_attrs[] = {
+ &interrupt_enable.attr,
+ &threshold_limit.attr,
+ &error_count.attr,
+ NULL
+};
+
+#define to_bank(k) container_of(k,struct threshold_bank,kobj)
+#define to_attr(a) container_of(a,struct threshold_attr,attr)
+
+static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+ struct threshold_bank *b = to_bank(kobj);
+ struct threshold_attr *a = to_attr(attr);
+ ssize_t ret;
+ ret = a->show ? a->show(b, buf) : -EIO;
+ return ret;
+}
+
+static ssize_t store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct threshold_bank *b = to_bank(kobj);
+ struct threshold_attr *a = to_attr(attr);
+ ssize_t ret;
+ ret = a->store ? a->store(b, buf, count) : -EIO;
+ return ret;
+}
+
+static struct sysfs_ops threshold_ops = {
+ .show = show,
+ .store = store,
+};
+
+static struct kobj_type threshold_ktype = {
+ .sysfs_ops = &threshold_ops,
+ .default_attrs = default_attrs,
+};
+
+/* symlinks sibling shared banks to first core. first core owns dir/files. */
+static __cpuinit int threshold_create_bank(unsigned int cpu, int bank)
+{
+ int err = 0;
+ struct threshold_bank *b = 0;
+
+#ifdef CONFIG_SMP
+ if (cpu_core_id[cpu] && shared_bank[bank]) { /* symlink */
+ char name[16];
+ unsigned lcpu = first_cpu(cpu_core_map[cpu]);
+ if (cpu_core_id[lcpu])
+ goto out; /* first core not up yet */
+
+ b = per_cpu(threshold_banks, lcpu)[bank];
+ if (!b)
+ goto out;
+ sprintf(name, "bank%i", bank);
+ err = sysfs_create_link(&per_cpu(device_threshold, cpu).kobj,
+ &b->kobj, name);
+ if (err)
+ goto out;
+ per_cpu(threshold_banks, cpu)[bank] = b;
+ goto out;
+ }
+#endif
+
+ b = kmalloc(sizeof(struct threshold_bank), GFP_KERNEL);
+ if (!b) {
+ err = -ENOMEM;
+ goto out;
+ }
+ memset(b, 0, sizeof(struct threshold_bank));
+
+ b->cpu = cpu;
+ b->bank = bank;
+ b->interrupt_enable = 0;
+ b->threshold_limit = THRESHOLD_MAX;
+ kobject_set_name(&b->kobj, "bank%i", bank);
+ b->kobj.parent = &per_cpu(device_threshold, cpu).kobj;
+ b->kobj.ktype = &threshold_ktype;
+
+ err = kobject_register(&b->kobj);
+ if (err) {
+ kfree(b);
+ goto out;
+ }
+ per_cpu(threshold_banks, cpu)[bank] = b;
+ out:
+ return err;
+}
+
+/* create dir/files for all valid threshold banks */
+static __cpuinit int threshold_create_device(unsigned int cpu)
+{
+ int bank;
+ int err = 0;
+
+ per_cpu(device_threshold, cpu).id = cpu;
+ per_cpu(device_threshold, cpu).cls = &threshold_sysclass;
+ err = sysdev_register(&per_cpu(device_threshold, cpu));
+ if (err)
+ goto out;
+
+ for (bank = 0; bank < NR_BANKS; ++bank) {
+ if (!(per_cpu(bank_map, cpu) & 1 << bank))
+ continue;
+ err = threshold_create_bank(cpu, bank);
+ if (err)
+ goto out;
+ }
+ out:
+ return err;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * let's be hotplug friendly.
+ * in case of multiple core processors, the first core always takes ownership
+ * of shared sysfs dir/files, and rest of the cores will be symlinked to it.
+ */
+
+/* cpu hotplug call removes all symlinks before first core dies */
+static __cpuinit void threshold_remove_bank(unsigned int cpu, int bank)
+{
+ struct threshold_bank *b;
+ char name[16];
+
+ b = per_cpu(threshold_banks, cpu)[bank];
+ if (!b)
+ return;
+ if (shared_bank[bank] && atomic_read(&b->kobj.kref.refcount) > 2) {
+ sprintf(name, "bank%i", bank);
+ sysfs_remove_link(&per_cpu(device_threshold, cpu).kobj, name);
+ per_cpu(threshold_banks, cpu)[bank] = 0;
+ } else {
+ kobject_unregister(&b->kobj);
+ kfree(per_cpu(threshold_banks, cpu)[bank]);
+ }
+}
+
+static __cpuinit void threshold_remove_device(unsigned int cpu)
+{
+ int bank;
+
+ for (bank = 0; bank < NR_BANKS; ++bank) {
+ if (!(per_cpu(bank_map, cpu) & 1 << bank))
+ continue;
+ threshold_remove_bank(cpu, bank);
+ }
+ sysdev_unregister(&per_cpu(device_threshold, cpu));
+}
+
+/* link all existing siblings when first core comes up */
+static __cpuinit int threshold_create_symlinks(unsigned int cpu)
+{
+ int bank, err = 0;
+ unsigned int lcpu = 0;
+
+ if (cpu_core_id[cpu])
+ return 0;
+ for_each_cpu_mask(lcpu, cpu_core_map[cpu]) {
+ if (lcpu == cpu)
+ continue;
+ for (bank = 0; bank < NR_BANKS; ++bank) {
+ if (!(per_cpu(bank_map, cpu) & 1 << bank))
+ continue;
+ if (!shared_bank[bank])
+ continue;
+ err = threshold_create_bank(lcpu, bank);
+ }
+ }
+ return err;
+}
+
+/* remove all symlinks before first core dies. */
+static __cpuinit void threshold_remove_symlinks(unsigned int cpu)
+{
+ int bank;
+ unsigned int lcpu = 0;
+ if (cpu_core_id[cpu])
+ return;
+ for_each_cpu_mask(lcpu, cpu_core_map[cpu]) {
+ if (lcpu == cpu)
+ continue;
+ for (bank = 0; bank < NR_BANKS; ++bank) {
+ if (!(per_cpu(bank_map, cpu) & 1 << bank))
+ continue;
+ if (!shared_bank[bank])
+ continue;
+ threshold_remove_bank(lcpu, bank);
+ }
+ }
+}
+#else /* !CONFIG_HOTPLUG_CPU */
+static __cpuinit void threshold_create_symlinks(unsigned int cpu)
+{
+}
+static __cpuinit void threshold_remove_symlinks(unsigned int cpu)
+{
+}
+static void threshold_remove_device(unsigned int cpu)
+{
+}
+#endif
+
+/* get notified when a cpu comes on/off */
+static __cpuinit int threshold_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ /* cpu was unsigned int to begin with */
+ unsigned int cpu = (unsigned long)hcpu;
+
+ if (cpu >= NR_CPUS)
+ goto out;
+
+ switch (action) {
+ case CPU_ONLINE:
+ threshold_create_device(cpu);
+ threshold_create_symlinks(cpu);
+ break;
+ case CPU_DOWN_PREPARE:
+ threshold_remove_symlinks(cpu);
+ break;
+ case CPU_DOWN_FAILED:
+ threshold_create_symlinks(cpu);
+ break;
+ case CPU_DEAD:
+ threshold_remove_device(cpu);
+ break;
+ default:
+ break;
+ }
+ out:
+ return NOTIFY_OK;
+}
+
+static struct notifier_block threshold_cpu_notifier = {
+ .notifier_call = threshold_cpu_callback,
+};
+
+static __init int threshold_init_device(void)
+{
+ int err;
+ int lcpu = 0;
+
+ err = sysdev_class_register(&threshold_sysclass);
+ if (err)
+ goto out;
+
+ /* to hit CPUs online before the notifier is up */
+ for_each_online_cpu(lcpu) {
+ err = threshold_create_device(lcpu);
+ if (err)
+ goto out;
+ }
+ register_cpu_notifier(&threshold_cpu_notifier);
+
+ out:
+ return err;
+}
+
+device_initcall(threshold_init_device);
projects / kernel / kernel-generic.git / commitdiff