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Diffstat (limited to 'arch/x86/kernel/cpu/cpufreq/powernow-k8.c')
-rw-r--r--arch/x86/kernel/cpu/cpufreq/powernow-k8.c169
1 files changed, 159 insertions, 10 deletions
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
index b6215b9798e..6f3dc8fbbfd 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
@@ -1,6 +1,5 @@
-
/*
- * (c) 2003-2006 Advanced Micro Devices, Inc.
+ * (c) 2003-2010 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
@@ -46,6 +45,7 @@
#define PFX "powernow-k8: "
#define VERSION "version 2.20.00"
#include "powernow-k8.h"
+#include "mperf.h"
/* serialize freq changes */
static DEFINE_MUTEX(fidvid_mutex);
@@ -54,6 +54,12 @@ static DEFINE_PER_CPU(struct powernow_k8_data *, powernow_data);
static int cpu_family = CPU_OPTERON;
+/* core performance boost */
+static bool cpb_capable, cpb_enabled;
+static struct msr __percpu *msrs;
+
+static struct cpufreq_driver cpufreq_amd64_driver;
+
#ifndef CONFIG_SMP
static inline const struct cpumask *cpu_core_mask(int cpu)
{
@@ -1249,6 +1255,7 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol)
struct powernow_k8_data *data;
struct init_on_cpu init_on_cpu;
int rc;
+ struct cpuinfo_x86 *c = &cpu_data(pol->cpu);
if (!cpu_online(pol->cpu))
return -ENODEV;
@@ -1323,6 +1330,10 @@ static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol)
return -EINVAL;
}
+ /* Check for APERF/MPERF support in hardware */
+ if (cpu_has(c, X86_FEATURE_APERFMPERF))
+ cpufreq_amd64_driver.getavg = cpufreq_get_measured_perf;
+
cpufreq_frequency_table_get_attr(data->powernow_table, pol->cpu);
if (cpu_family == CPU_HW_PSTATE)
@@ -1394,8 +1405,77 @@ out:
return khz;
}
+static void _cpb_toggle_msrs(bool t)
+{
+ int cpu;
+
+ get_online_cpus();
+
+ rdmsr_on_cpus(cpu_online_mask, MSR_K7_HWCR, msrs);
+
+ for_each_cpu(cpu, cpu_online_mask) {
+ struct msr *reg = per_cpu_ptr(msrs, cpu);
+ if (t)
+ reg->l &= ~BIT(25);
+ else
+ reg->l |= BIT(25);
+ }
+ wrmsr_on_cpus(cpu_online_mask, MSR_K7_HWCR, msrs);
+
+ put_online_cpus();
+}
+
+/*
+ * Switch on/off core performance boosting.
+ *
+ * 0=disable
+ * 1=enable.
+ */
+static void cpb_toggle(bool t)
+{
+ if (!cpb_capable)
+ return;
+
+ if (t && !cpb_enabled) {
+ cpb_enabled = true;
+ _cpb_toggle_msrs(t);
+ printk(KERN_INFO PFX "Core Boosting enabled.\n");
+ } else if (!t && cpb_enabled) {
+ cpb_enabled = false;
+ _cpb_toggle_msrs(t);
+ printk(KERN_INFO PFX "Core Boosting disabled.\n");
+ }
+}
+
+static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
+ size_t count)
+{
+ int ret = -EINVAL;
+ unsigned long val = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (!ret && (val == 0 || val == 1) && cpb_capable)
+ cpb_toggle(val);
+ else
+ return -EINVAL;
+
+ return count;
+}
+
+static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
+{
+ return sprintf(buf, "%u\n", cpb_enabled);
+}
+
+#define define_one_rw(_name) \
+static struct freq_attr _name = \
+__ATTR(_name, 0644, show_##_name, store_##_name)
+
+define_one_rw(cpb);
+
static struct freq_attr *powernow_k8_attr[] = {
&cpufreq_freq_attr_scaling_available_freqs,
+ &cpb,
NULL,
};
@@ -1411,10 +1491,51 @@ static struct cpufreq_driver cpufreq_amd64_driver = {
.attr = powernow_k8_attr,
};
+/*
+ * Clear the boost-disable flag on the CPU_DOWN path so that this cpu
+ * cannot block the remaining ones from boosting. On the CPU_UP path we
+ * simply keep the boost-disable flag in sync with the current global
+ * state.
+ */
+static int __cpuinit cpb_notify(struct notifier_block *nb, unsigned long action,
+ void *hcpu)
+{
+ unsigned cpu = (long)hcpu;
+ u32 lo, hi;
+
+ switch (action) {
+ case CPU_UP_PREPARE:
+ case CPU_UP_PREPARE_FROZEN:
+
+ if (!cpb_enabled) {
+ rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
+ lo |= BIT(25);
+ wrmsr_on_cpu(cpu, MSR_K7_HWCR, lo, hi);
+ }
+ break;
+
+ case CPU_DOWN_PREPARE:
+ case CPU_DOWN_PREPARE_FROZEN:
+ rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
+ lo &= ~BIT(25);
+ wrmsr_on_cpu(cpu, MSR_K7_HWCR, lo, hi);
+ break;
+
+ default:
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata cpb_nb = {
+ .notifier_call = cpb_notify,
+};
+
/* driver entry point for init */
static int __cpuinit powernowk8_init(void)
{
- unsigned int i, supported_cpus = 0;
+ unsigned int i, supported_cpus = 0, cpu;
for_each_online_cpu(i) {
int rc;
@@ -1423,15 +1544,36 @@ static int __cpuinit powernowk8_init(void)
supported_cpus++;
}
- if (supported_cpus == num_online_cpus()) {
- printk(KERN_INFO PFX "Found %d %s "
- "processors (%d cpu cores) (" VERSION ")\n",
- num_online_nodes(),
- boot_cpu_data.x86_model_id, supported_cpus);
- return cpufreq_register_driver(&cpufreq_amd64_driver);
+ if (supported_cpus != num_online_cpus())
+ return -ENODEV;
+
+ printk(KERN_INFO PFX "Found %d %s (%d cpu cores) (" VERSION ")\n",
+ num_online_nodes(), boot_cpu_data.x86_model_id, supported_cpus);
+
+ if (boot_cpu_has(X86_FEATURE_CPB)) {
+
+ cpb_capable = true;
+
+ register_cpu_notifier(&cpb_nb);
+
+ msrs = msrs_alloc();
+ if (!msrs) {
+ printk(KERN_ERR "%s: Error allocating msrs!\n", __func__);
+ return -ENOMEM;
+ }
+
+ rdmsr_on_cpus(cpu_online_mask, MSR_K7_HWCR, msrs);
+
+ for_each_cpu(cpu, cpu_online_mask) {
+ struct msr *reg = per_cpu_ptr(msrs, cpu);
+ cpb_enabled |= !(!!(reg->l & BIT(25)));
+ }
+
+ printk(KERN_INFO PFX "Core Performance Boosting: %s.\n",
+ (cpb_enabled ? "on" : "off"));
}
- return -ENODEV;
+ return cpufreq_register_driver(&cpufreq_amd64_driver);
}
/* driver entry point for term */
@@ -1439,6 +1581,13 @@ static void __exit powernowk8_exit(void)
{
dprintk("exit\n");
+ if (boot_cpu_has(X86_FEATURE_CPB)) {
+ msrs_free(msrs);
+ msrs = NULL;
+
+ unregister_cpu_notifier(&cpb_nb);
+ }
+
cpufreq_unregister_driver(&cpufreq_amd64_driver);
}