ACPI: Discard invalid elements in _PSS package
[safe/jmp/linux-2.6] / arch / i386 / kernel / cpu / cpufreq / acpi-cpufreq.c
index 07fd97b..9ba2b69 100644 (file)
@@ -32,7 +32,6 @@
 #include <linux/sched.h>
 #include <linux/cpufreq.h>
 #include <linux/compiler.h>
-#include <linux/sched.h>       /* current */
 #include <linux/dmi.h>
 
 #include <linux/acpi.h>
@@ -51,7 +50,6 @@ MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
 MODULE_LICENSE("GPL");
 
-
 enum {
        UNDEFINED_CAPABLE = 0,
        SYSTEM_INTEL_MSR_CAPABLE,
@@ -59,97 +57,75 @@ enum {
 };
 
 #define INTEL_MSR_RANGE                (0xffff)
+#define CPUID_6_ECX_APERFMPERF_CAPABILITY      (0x1)
 
 struct acpi_cpufreq_data {
-       struct acpi_processor_performance       *acpi_data;
-       struct cpufreq_frequency_table          *freq_table;
-       unsigned int                            resume;
-       unsigned int                            cpu_feature;
+       struct acpi_processor_performance *acpi_data;
+       struct cpufreq_frequency_table *freq_table;
+       unsigned int max_freq;
+       unsigned int resume;
+       unsigned int cpu_feature;
 };
 
-static struct acpi_cpufreq_data        *drv_data[NR_CPUS];
-static struct acpi_processor_performance       *acpi_perf_data[NR_CPUS];
+static struct acpi_cpufreq_data *drv_data[NR_CPUS];
+static struct acpi_processor_performance *acpi_perf_data[NR_CPUS];
 
 static struct cpufreq_driver acpi_cpufreq_driver;
 
 static unsigned int acpi_pstate_strict;
 
-
 static int check_est_cpu(unsigned int cpuid)
 {
        struct cpuinfo_x86 *cpu = &cpu_data[cpuid];
 
        if (cpu->x86_vendor != X86_VENDOR_INTEL ||
-                       !cpu_has(cpu, X86_FEATURE_EST))
+           !cpu_has(cpu, X86_FEATURE_EST))
                return 0;
 
        return 1;
 }
 
-
 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
 {
-       struct acpi_processor_performance       *perf;
-       int                                     i;
+       struct acpi_processor_performance *perf;
+       int i;
 
        perf = data->acpi_data;
 
-       for (i = 0; i < perf->state_count; i++) {
+       for (i=0; i<perf->state_count; i++) {
                if (value == perf->states[i].status)
                        return data->freq_table[i].frequency;
        }
        return 0;
 }
 
-
 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
 {
        int i;
+       struct acpi_processor_performance *perf;
 
        msr &= INTEL_MSR_RANGE;
-       for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
-               if (msr == data->freq_table[i].index)
+       perf = data->acpi_data;
+
+       for (i=0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
+               if (msr == perf->states[data->freq_table[i].index].status)
                        return data->freq_table[i].frequency;
        }
        return data->freq_table[0].frequency;
 }
 
-
 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
 {
        switch (data->cpu_feature) {
-           case SYSTEM_INTEL_MSR_CAPABLE:
+       case SYSTEM_INTEL_MSR_CAPABLE:
                return extract_msr(val, data);
-           case SYSTEM_IO_CAPABLE:
+       case SYSTEM_IO_CAPABLE:
                return extract_io(val, data);
-           default:
+       default:
                return 0;
        }
 }
 
-static void wrport(u16 port, u8 bit_width, u32 value)
-{
-       if (bit_width <= 8) {
-               outb(value, port);
-       } else if (bit_width <= 16) {
-               outw(value, port);
-       } else if (bit_width <= 32) {
-               outl(value, port);
-       }
-}
-
-static void rdport(u16 port, u8 bit_width, u32 *ret)
-{
-       *ret = 0;
-       if (bit_width <= 8) {
-               *ret = inb(port);
-       } else if (bit_width <= 16) {
-               *ret = inw(port);
-       } else if (bit_width <= 32) {
-               *ret = inl(port);
-       }
-}
-
 struct msr_addr {
        u32 reg;
 };
@@ -176,13 +152,15 @@ static void do_drv_read(struct drv_cmd *cmd)
        u32 h;
 
        switch (cmd->type) {
-           case SYSTEM_INTEL_MSR_CAPABLE:
+       case SYSTEM_INTEL_MSR_CAPABLE:
                rdmsr(cmd->addr.msr.reg, cmd->val, h);
                break;
-           case SYSTEM_IO_CAPABLE:
-               rdport(cmd->addr.io.port, cmd->addr.io.bit_width, &cmd->val);
+       case SYSTEM_IO_CAPABLE:
+               acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
+                               &cmd->val,
+                               (u32)cmd->addr.io.bit_width);
                break;
-           default:
+       default:
                break;
        }
 }
@@ -192,32 +170,33 @@ static void do_drv_write(struct drv_cmd *cmd)
        u32 h = 0;
 
        switch (cmd->type) {
-           case SYSTEM_INTEL_MSR_CAPABLE:
+       case SYSTEM_INTEL_MSR_CAPABLE:
                wrmsr(cmd->addr.msr.reg, cmd->val, h);
                break;
-           case SYSTEM_IO_CAPABLE:
-               wrport(cmd->addr.io.port, cmd->addr.io.bit_width, cmd->val);
+       case SYSTEM_IO_CAPABLE:
+               acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
+                               cmd->val,
+                               (u32)cmd->addr.io.bit_width);
                break;
-           default:
+       default:
                break;
        }
 }
 
-static inline void drv_read(struct drv_cmd *cmd)
+static void drv_read(struct drv_cmd *cmd)
 {
-       cpumask_t       saved_mask = current->cpus_allowed;
+       cpumask_t saved_mask = current->cpus_allowed;
        cmd->val = 0;
 
        set_cpus_allowed(current, cmd->mask);
        do_drv_read(cmd);
        set_cpus_allowed(current, saved_mask);
-
 }
 
 static void drv_write(struct drv_cmd *cmd)
 {
-       cpumask_t       saved_mask = current->cpus_allowed;
-       unsigned int    i;
+       cpumask_t saved_mask = current->cpus_allowed;
+       unsigned int i;
 
        for_each_cpu_mask(i, cmd->mask) {
                set_cpus_allowed(current, cpumask_of_cpu(i));
@@ -230,8 +209,8 @@ static void drv_write(struct drv_cmd *cmd)
 
 static u32 get_cur_val(cpumask_t mask)
 {
-       struct acpi_processor_performance       *perf;
-       struct drv_cmd                          cmd;
+       struct acpi_processor_performance *perf;
+       struct drv_cmd cmd;
 
        if (unlikely(cpus_empty(mask)))
                return 0;
@@ -260,16 +239,107 @@ static u32 get_cur_val(cpumask_t mask)
        return cmd.val;
 }
 
+/*
+ * Return the measured active (C0) frequency on this CPU since last call
+ * to this function.
+ * Input: cpu number
+ * Return: Average CPU frequency in terms of max frequency (zero on error)
+ *
+ * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
+ * over a period of time, while CPU is in C0 state.
+ * IA32_MPERF counts at the rate of max advertised frequency
+ * IA32_APERF counts at the rate of actual CPU frequency
+ * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
+ * no meaning should be associated with absolute values of these MSRs.
+ */
+static unsigned int get_measured_perf(unsigned int cpu)
+{
+       union {
+               struct {
+                       u32 lo;
+                       u32 hi;
+               } split;
+               u64 whole;
+       } aperf_cur, mperf_cur;
+
+       cpumask_t saved_mask;
+       unsigned int perf_percent;
+       unsigned int retval;
+
+       saved_mask = current->cpus_allowed;
+       set_cpus_allowed(current, cpumask_of_cpu(cpu));
+       if (get_cpu() != cpu) {
+               /* We were not able to run on requested processor */
+               put_cpu();
+               return 0;
+       }
+
+       rdmsr(MSR_IA32_APERF, aperf_cur.split.lo, aperf_cur.split.hi);
+       rdmsr(MSR_IA32_MPERF, mperf_cur.split.lo, mperf_cur.split.hi);
+
+       wrmsr(MSR_IA32_APERF, 0,0);
+       wrmsr(MSR_IA32_MPERF, 0,0);
+
+#ifdef __i386__
+       /*
+        * We dont want to do 64 bit divide with 32 bit kernel
+        * Get an approximate value. Return failure in case we cannot get
+        * an approximate value.
+        */
+       if (unlikely(aperf_cur.split.hi || mperf_cur.split.hi)) {
+               int shift_count;
+               u32 h;
+
+               h = max_t(u32, aperf_cur.split.hi, mperf_cur.split.hi);
+               shift_count = fls(h);
+
+               aperf_cur.whole >>= shift_count;
+               mperf_cur.whole >>= shift_count;
+       }
+
+       if (((unsigned long)(-1) / 100) < aperf_cur.split.lo) {
+               int shift_count = 7;
+               aperf_cur.split.lo >>= shift_count;
+               mperf_cur.split.lo >>= shift_count;
+       }
+
+       if (aperf_cur.split.lo && mperf_cur.split.lo)
+               perf_percent = (aperf_cur.split.lo * 100) / mperf_cur.split.lo;
+       else
+               perf_percent = 0;
+
+#else
+       if (unlikely(((unsigned long)(-1) / 100) < aperf_cur.whole)) {
+               int shift_count = 7;
+               aperf_cur.whole >>= shift_count;
+               mperf_cur.whole >>= shift_count;
+       }
+
+       if (aperf_cur.whole && mperf_cur.whole)
+               perf_percent = (aperf_cur.whole * 100) / mperf_cur.whole;
+       else
+               perf_percent = 0;
+
+#endif
+
+       retval = drv_data[cpu]->max_freq * perf_percent / 100;
+
+       put_cpu();
+       set_cpus_allowed(current, saved_mask);
+
+       dprintk("cpu %d: performance percent %d\n", cpu, perf_percent);
+       return retval;
+}
+
 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 {
-       struct acpi_cpufreq_data                *data = drv_data[cpu];
-       unsigned int                            freq;
+       struct acpi_cpufreq_data *data = drv_data[cpu];
+       unsigned int freq;
 
        dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
 
        if (unlikely(data == NULL ||
-                    data->acpi_data == NULL ||
-                    data->freq_table == NULL)) {
+                    data->acpi_data == NULL || data->freq_table == NULL)) {
                return 0;
        }
 
@@ -280,12 +350,12 @@ static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 }
 
 static unsigned int check_freqs(cpumask_t mask, unsigned int freq,
-               struct acpi_cpufreq_data *data)
+                               struct acpi_cpufreq_data *data)
 {
-       unsigned int    cur_freq;
-       unsigned int    i;
+       unsigned int cur_freq;
+       unsigned int i;
 
-       for (i = 0; i < 100; i++) {
+       for (i=0; i<100; i++) {
                cur_freq = extract_freq(get_cur_val(mask), data);
                if (cur_freq == freq)
                        return 1;
@@ -295,34 +365,31 @@ static unsigned int check_freqs(cpumask_t mask, unsigned int freq,
 }
 
 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
-                               unsigned int target_freq,
-                               unsigned int relation)
+                              unsigned int target_freq, unsigned int relation)
 {
-       struct acpi_cpufreq_data                *data = drv_data[policy->cpu];
-       struct acpi_processor_performance       *perf;
-       struct cpufreq_freqs                    freqs;
-       cpumask_t                               online_policy_cpus;
-       struct drv_cmd                          cmd;
-       unsigned int                            msr;
-       unsigned int                            next_state = 0;
-       unsigned int                            next_perf_state = 0;
-       unsigned int                            i;
-       int                                     result = 0;
+       struct acpi_cpufreq_data *data = drv_data[policy->cpu];
+       struct acpi_processor_performance *perf;
+       struct cpufreq_freqs freqs;
+       cpumask_t online_policy_cpus;
+       struct drv_cmd cmd;
+       unsigned int msr;
+       unsigned int next_state = 0; /* Index into freq_table */
+       unsigned int next_perf_state = 0; /* Index into perf table */
+       unsigned int i;
+       int result = 0;
 
        dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
 
        if (unlikely(data == NULL ||
-                    data->acpi_data == NULL ||
-                    data->freq_table == NULL)) {
+            data->acpi_data == NULL || data->freq_table == NULL)) {
                return -ENODEV;
        }
 
        perf = data->acpi_data;
        result = cpufreq_frequency_table_target(policy,
-                                               data->freq_table,
-                                               target_freq,
-                                               relation,
-                                               &next_state);
+                                               data->freq_table,
+                                               target_freq,
+                                               relation, &next_state);
        if (unlikely(result))
                return -ENODEV;
 
@@ -333,36 +400,38 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy,
        online_policy_cpus = policy->cpus;
 #endif
 
-       cmd.val = get_cur_val(online_policy_cpus);
-       freqs.old = extract_freq(cmd.val, data);
-       freqs.new = data->freq_table[next_state].frequency;
        next_perf_state = data->freq_table[next_state].index;
-       if (freqs.new == freqs.old) {
+       if (perf->state == next_perf_state) {
                if (unlikely(data->resume)) {
-                       dprintk("Called after resume, resetting to P%d\n", next_perf_state);
+                       dprintk("Called after resume, resetting to P%d\n",
+                               next_perf_state);
                        data->resume = 0;
                } else {
-                       dprintk("Already at target state (P%d)\n", next_perf_state);
+                       dprintk("Already at target state (P%d)\n",
+                               next_perf_state);
                        return 0;
                }
        }
 
-       switch (data->cpu_feature) {
-           case SYSTEM_INTEL_MSR_CAPABLE:
-               cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
-               cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
-               msr = (u32) perf->states[next_perf_state].control & INTEL_MSR_RANGE;
-               cmd.val = (cmd.val & ~INTEL_MSR_RANGE) | msr;
-               break;
-           case SYSTEM_IO_CAPABLE:
-               cmd.type = SYSTEM_IO_CAPABLE;
-               cmd.addr.io.port = perf->control_register.address;
-               cmd.addr.io.bit_width = perf->control_register.bit_width;
-               cmd.val = (u32) perf->states[next_perf_state].control;
-               break;
-           default:
-               return -ENODEV;
-       }
+       switch (data->cpu_feature) {
+       case SYSTEM_INTEL_MSR_CAPABLE:
+               cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
+               cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
+               msr =
+                   (u32) perf->states[next_perf_state].
+                   control & INTEL_MSR_RANGE;
+               cmd.val = get_cur_val(online_policy_cpus);
+               cmd.val = (cmd.val & ~INTEL_MSR_RANGE) | msr;
+               break;
+       case SYSTEM_IO_CAPABLE:
+               cmd.type = SYSTEM_IO_CAPABLE;
+               cmd.addr.io.port = perf->control_register.address;
+               cmd.addr.io.bit_width = perf->control_register.bit_width;
+               cmd.val = (u32) perf->states[next_perf_state].control;
+               break;
+       default:
+               return -ENODEV;
+       }
 
        cpus_clear(cmd.mask);
 
@@ -371,6 +440,8 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy,
        else
                cpu_set(policy->cpu, cmd.mask);
 
+       freqs.old = perf->states[perf->state].core_frequency * 1000;
+       freqs.new = data->freq_table[next_state].frequency;
        for_each_cpu_mask(i, cmd.mask) {
                freqs.cpu = i;
                cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
@@ -381,7 +452,7 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy,
        if (acpi_pstate_strict) {
                if (!check_freqs(cmd.mask, freqs.new, data)) {
                        dprintk("acpi_cpufreq_target failed (%d)\n",
-                                       policy->cpu);
+                               policy->cpu);
                        return -EAGAIN;
                }
        }
@@ -395,10 +466,7 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy,
        return result;
 }
 
-
-static int
-acpi_cpufreq_verify (
-       struct cpufreq_policy   *policy)
+static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
 {
        struct acpi_cpufreq_data *data = drv_data[policy->cpu];
 
@@ -407,13 +475,10 @@ acpi_cpufreq_verify (
        return cpufreq_frequency_table_verify(policy, data->freq_table);
 }
 
-
 static unsigned long
-acpi_cpufreq_guess_freq (
-       struct acpi_cpufreq_data        *data,
-       unsigned int            cpu)
+acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 {
-       struct acpi_processor_performance       *perf = data->acpi_data;
+       struct acpi_processor_performance *perf = data->acpi_data;
 
        if (cpu_khz) {
                /* search the closest match to cpu_khz */
@@ -421,16 +486,16 @@ acpi_cpufreq_guess_freq (
                unsigned long freq;
                unsigned long freqn = perf->states[0].core_frequency * 1000;
 
-               for (i = 0; i < (perf->state_count - 1); i++) {
+               for (i=0; i<(perf->state_count-1); i++) {
                        freq = freqn;
                        freqn = perf->states[i+1].core_frequency * 1000;
                        if ((2 * cpu_khz) > (freqn + freq)) {
                                perf->state = i;
-                               return (freq);
+                               return freq;
                        }
                }
-               perf->state = perf->state_count - 1;
-               return (freqn);
+               perf->state = perf->state_count-1;
+               return freqn;
        } else {
                /* assume CPU is at P0... */
                perf->state = 0;
@@ -438,7 +503,6 @@ acpi_cpufreq_guess_freq (
        }
 }
 
-
 /*
  * acpi_cpufreq_early_init - initialize ACPI P-States library
  *
@@ -449,21 +513,21 @@ acpi_cpufreq_guess_freq (
  */
 static int acpi_cpufreq_early_init(void)
 {
-       struct acpi_processor_performance       *data;
-       cpumask_t                               covered;
-       unsigned int                            i, j;
+       struct acpi_processor_performance *data;
+       cpumask_t covered;
+       unsigned int i, j;
 
        dprintk("acpi_cpufreq_early_init\n");
 
        for_each_possible_cpu(i) {
-               data = kzalloc(sizeof(struct acpi_processor_performance), 
-                       GFP_KERNEL);
+               data = kzalloc(sizeof(struct acpi_processor_performance),
+                              GFP_KERNEL);
                if (!data) {
                        for_each_cpu_mask(j, covered) {
                                kfree(acpi_perf_data[j]);
                                acpi_perf_data[j] = NULL;
                        }
-                       return (-ENOMEM);
+                       return -ENOMEM;
                }
                acpi_perf_data[i] = data;
                cpu_set(i, covered);
@@ -474,6 +538,7 @@ static int acpi_cpufreq_early_init(void)
        return 0;
 }
 
+#ifdef CONFIG_SMP
 /*
  * Some BIOSes do SW_ANY coordination internally, either set it up in hw
  * or do it in BIOS firmware and won't inform about it to OS. If not
@@ -500,35 +565,32 @@ static struct dmi_system_id sw_any_bug_dmi_table[] = {
        },
        { }
 };
+#endif
 
-static int
-acpi_cpufreq_cpu_init (
-       struct cpufreq_policy   *policy)
+static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 {
-       unsigned int                    i;
-       unsigned int                    valid_states = 0;
-       unsigned int                    cpu = policy->cpu;
-       struct acpi_cpufreq_data        *data;
-       unsigned int                    l, h;
-       unsigned int                    result = 0;
-       struct cpuinfo_x86              *c = &cpu_data[policy->cpu];
-       struct acpi_processor_performance       *perf;
+       unsigned int i;
+       unsigned int valid_states = 0;
+       unsigned int cpu = policy->cpu;
+       struct acpi_cpufreq_data *data;
+       unsigned int result = 0;
+       struct cpuinfo_x86 *c = &cpu_data[policy->cpu];
+       struct acpi_processor_performance *perf;
 
        dprintk("acpi_cpufreq_cpu_init\n");
 
        if (!acpi_perf_data[cpu])
-               return (-ENODEV);
+               return -ENODEV;
 
        data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
        if (!data)
-               return (-ENOMEM);
+               return -ENOMEM;
 
        data->acpi_data = acpi_perf_data[cpu];
        drv_data[cpu] = data;
 
-       if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
+       if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
                acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
-       }
 
        result = acpi_processor_register_performance(data->acpi_data, cpu);
        if (result)
@@ -536,8 +598,9 @@ acpi_cpufreq_cpu_init (
 
        perf = data->acpi_data;
        policy->shared_type = perf->shared_type;
+
        /*
-        * Will let policy->cpus know about dependency only when software 
+        * Will let policy->cpus know about dependency only when software
         * coordination is required.
         */
        if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
@@ -566,11 +629,11 @@ acpi_cpufreq_cpu_init (
        }
 
        switch (perf->control_register.space_id) {
-           case ACPI_ADR_SPACE_SYSTEM_IO:
+       case ACPI_ADR_SPACE_SYSTEM_IO:
                dprintk("SYSTEM IO addr space\n");
                data->cpu_feature = SYSTEM_IO_CAPABLE;
                break;
-           case ACPI_ADR_SPACE_FIXED_HARDWARE:
+       case ACPI_ADR_SPACE_FIXED_HARDWARE:
                dprintk("HARDWARE addr space\n");
                if (!check_est_cpu(cpu)) {
                        result = -ENODEV;
@@ -578,14 +641,15 @@ acpi_cpufreq_cpu_init (
                }
                data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
                break;
-           default:
+       default:
                dprintk("Unknown addr space %d\n",
-                               (u32) (perf->control_register.space_id));
+                       (u32) (perf->control_register.space_id));
                result = -ENODEV;
                goto err_unreg;
        }
 
-       data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) * (perf->state_count + 1), GFP_KERNEL);
+       data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
+                   (perf->state_count+1), GFP_KERNEL);
        if (!data->freq_table) {
                result = -ENOMEM;
                goto err_unreg;
@@ -594,142 +658,141 @@ acpi_cpufreq_cpu_init (
        /* detect transition latency */
        policy->cpuinfo.transition_latency = 0;
        for (i=0; i<perf->state_count; i++) {
-               if ((perf->states[i].transition_latency * 1000) > policy->cpuinfo.transition_latency)
-                       policy->cpuinfo.transition_latency = perf->states[i].transition_latency * 1000;
+               if ((perf->states[i].transition_latency * 1000) >
+                   policy->cpuinfo.transition_latency)
+                       policy->cpuinfo.transition_latency =
+                           perf->states[i].transition_latency * 1000;
        }
        policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
 
+       data->max_freq = perf->states[0].core_frequency * 1000;
        /* table init */
-       for (i=0; i<perf->state_count; i++)
-       {
-               if ( i > 0 && perf->states[i].core_frequency ==
-                               perf->states[i - 1].core_frequency)
+       for (i=0; i<perf->state_count; i++) {
+               if (i>0 && perf->states[i].core_frequency >=
+                   data->freq_table[valid_states-1].frequency / 1000)
                        continue;
 
                data->freq_table[valid_states].index = i;
                data->freq_table[valid_states].frequency =
-                       perf->states[i].core_frequency * 1000;
+                   perf->states[i].core_frequency * 1000;
                valid_states++;
        }
-       data->freq_table[perf->state_count].frequency = CPUFREQ_TABLE_END;
+       data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
+       perf->state = 0;
 
        result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
-       if (result) {
+       if (result)
                goto err_freqfree;
-       }
 
-       switch (data->cpu_feature) {
-           case ACPI_ADR_SPACE_SYSTEM_IO:
+       switch (perf->control_register.space_id) {
+       case ACPI_ADR_SPACE_SYSTEM_IO:
                /* Current speed is unknown and not detectable by IO port */
                policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
                break;
-           case ACPI_ADR_SPACE_FIXED_HARDWARE:
-               get_cur_freq_on_cpu(cpu);
+       case ACPI_ADR_SPACE_FIXED_HARDWARE:
+               acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
+               policy->cur = get_cur_freq_on_cpu(cpu);
                break;
-           default:
+       default:
                break;
        }
 
        /* notify BIOS that we exist */
        acpi_processor_notify_smm(THIS_MODULE);
 
+       /* Check for APERF/MPERF support in hardware */
+       if (c->x86_vendor == X86_VENDOR_INTEL && c->cpuid_level >= 6) {
+               unsigned int ecx;
+               ecx = cpuid_ecx(6);
+               if (ecx & CPUID_6_ECX_APERFMPERF_CAPABILITY)
+                       acpi_cpufreq_driver.getavg = get_measured_perf;
+       }
+
        dprintk("CPU%u - ACPI performance management activated.\n", cpu);
        for (i = 0; i < perf->state_count; i++)
                dprintk("     %cP%d: %d MHz, %d mW, %d uS\n",
-                       (i == perf->state?'*':' '), i,
+                       (i == perf->state ? '*' : ' '), i,
                        (u32) perf->states[i].core_frequency,
                        (u32) perf->states[i].power,
                        (u32) perf->states[i].transition_latency);
 
        cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
-       
+
        /*
         * the first call to ->target() should result in us actually
         * writing something to the appropriate registers.
         */
        data->resume = 1;
-       
+
        return result;
 
- err_freqfree:
+err_freqfree:
        kfree(data->freq_table);
- err_unreg:
+err_unreg:
        acpi_processor_unregister_performance(perf, cpu);
- err_free:
+err_free:
        kfree(data);
        drv_data[cpu] = NULL;
 
-       return (result);
+       return result;
 }
 
-
-static int
-acpi_cpufreq_cpu_exit (
-       struct cpufreq_policy   *policy)
+static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 {
        struct acpi_cpufreq_data *data = drv_data[policy->cpu];
 
-
        dprintk("acpi_cpufreq_cpu_exit\n");
 
        if (data) {
                cpufreq_frequency_table_put_attr(policy->cpu);
                drv_data[policy->cpu] = NULL;
-               acpi_processor_unregister_performance(data->acpi_data, policy->cpu);
+               acpi_processor_unregister_performance(data->acpi_data,
+                                                     policy->cpu);
                kfree(data);
        }
 
-       return (0);
+       return 0;
 }
 
-static int
-acpi_cpufreq_resume (
-       struct cpufreq_policy   *policy)
+static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 {
        struct acpi_cpufreq_data *data = drv_data[policy->cpu];
 
-
        dprintk("acpi_cpufreq_resume\n");
 
        data->resume = 1;
 
-       return (0);
+       return 0;
 }
 
-
-static struct freq_attr* acpi_cpufreq_attr[] = {
+static struct freq_attr *acpi_cpufreq_attr[] = {
        &cpufreq_freq_attr_scaling_available_freqs,
        NULL,
 };
 
 static struct cpufreq_driver acpi_cpufreq_driver = {
-       .verify = acpi_cpufreq_verify,
-       .target = acpi_cpufreq_target,
-       .get    = get_cur_freq_on_cpu,
-       .init   = acpi_cpufreq_cpu_init,
-       .exit   = acpi_cpufreq_cpu_exit,
-       .resume = acpi_cpufreq_resume,
-       .name   = "acpi-cpufreq",
-       .owner  = THIS_MODULE,
-       .attr   = acpi_cpufreq_attr,
+       .verify = acpi_cpufreq_verify,
+       .target = acpi_cpufreq_target,
+       .init = acpi_cpufreq_cpu_init,
+       .exit = acpi_cpufreq_cpu_exit,
+       .resume = acpi_cpufreq_resume,
+       .name = "acpi-cpufreq",
+       .owner = THIS_MODULE,
+       .attr = acpi_cpufreq_attr,
 };
 
-
-static int __init
-acpi_cpufreq_init (void)
+static int __init acpi_cpufreq_init(void)
 {
        dprintk("acpi_cpufreq_init\n");
 
        acpi_cpufreq_early_init();
 
-       return cpufreq_register_driver(&acpi_cpufreq_driver);
+       return cpufreq_register_driver(&acpi_cpufreq_driver);
 }
 
-
-static void __exit
-acpi_cpufreq_exit (void)
+static void __exit acpi_cpufreq_exit(void)
 {
-       unsigned int    i;
+       unsigned int i;
        dprintk("acpi_cpufreq_exit\n");
 
        cpufreq_unregister_driver(&acpi_cpufreq_driver);
@@ -742,7 +805,9 @@ acpi_cpufreq_exit (void)
 }
 
 module_param(acpi_pstate_strict, uint, 0644);
-MODULE_PARM_DESC(acpi_pstate_strict, "value 0 or non-zero. non-zero -> strict ACPI checks are performed during frequency changes.");
+MODULE_PARM_DESC(acpi_pstate_strict,
+       "value 0 or non-zero. non-zero -> strict ACPI checks are "
+       "performed during frequency changes.");
 
 late_initcall(acpi_cpufreq_init);
 module_exit(acpi_cpufreq_exit);