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Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq 

* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Longhaul - Redo Longhaul ver. 2
  [CPUFREQ] EPS - Correct 2nd brand test
  [CPUFREQ] Longhaul - Separate frequency and voltage transition
  [CPUFREQ] Longhaul - Models of Nehemiah
  [CPUFREQ] Whitespace fixup
  [CPUFREQ] Longhaul - Simplier minmult
  [CPUFREQ] CPU_FREQ_TABLE shouldn't be a def_tristate
  [CPUFREQ] ondemand governor use new cpufreq rwsem locking in work callback
  [CPUFREQ] ondemand governor restructure the work callback
  [CPUFREQ] Rewrite lock in cpufreq to eliminate cpufreq/hotplug related issues
  [CPUFREQ] Remove hotplug cpu crap
  [CPUFREQ] Enhanced PowerSaver driver
  [CPUFREQ] Longhaul - Add VT8235 support
  [CPUFREQ] Longhaul - Fix guess_fsb function
  [CPUFREQ] Longhaul - Remove duplicate tables
  [CPUFREQ] Longhaul - Introduce Nehemiah C
  [CPUFREQ] fix cpuinfo_cur_freq for CPU_HW_PSTATE
  [CPUFREQ] Longhaul - Remove "ignore_latency" option
This commit is contained in:
Linus Torvalds 2007-02-16 08:16:01 -08:00
Родитель 0187f221e9 2b8c0e1302
Коммит ef29498655
13 изменённых файлов: 796 добавлений и 408 удалений
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9
arch/i386/kernel/cpu/cpufreq/Kconfig
Просмотреть файл

@ -217,6 +217,15 @@ config X86_LONGHAUL
If in doubt, say N.
config X86_E_POWERSAVER
tristate "VIA C7 Enhanced PowerSaver (EXPERIMENTAL)"
select CPU_FREQ_TABLE
depends on EXPERIMENTAL
help
This adds the CPUFreq driver for VIA C7 processors.
If in doubt, say N.
comment "shared options"
config X86_ACPI_CPUFREQ_PROC_INTF

1
arch/i386/kernel/cpu/cpufreq/Makefile
Просмотреть файл

@ -2,6 +2,7 @@ obj-$(CONFIG_X86_POWERNOW_K6) += powernow-k6.o
obj-$(CONFIG_X86_POWERNOW_K7) += powernow-k7.o
obj-$(CONFIG_X86_POWERNOW_K8) += powernow-k8.o
obj-$(CONFIG_X86_LONGHAUL) += longhaul.o
obj-$(CONFIG_X86_E_POWERSAVER) += e_powersaver.o
obj-$(CONFIG_ELAN_CPUFREQ) += elanfreq.o
obj-$(CONFIG_SC520_CPUFREQ) += sc520_freq.o
obj-$(CONFIG_X86_LONGRUN) += longrun.o

334
arch/i386/kernel/cpu/cpufreq/e_powersaver.c Normal file
Просмотреть файл

@ -0,0 +1,334 @@
/*
* Based on documentation provided by Dave Jones. Thanks!
*
* Licensed under the terms of the GNU GPL License version 2.
*
* BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <asm/msr.h>
#include <asm/tsc.h>
#include <asm/timex.h>
#include <asm/io.h>
#include <asm/delay.h>
#define EPS_BRAND_C7M 0
#define EPS_BRAND_C7 1
#define EPS_BRAND_EDEN 2
#define EPS_BRAND_C3 3
struct eps_cpu_data {
u32 fsb;
struct cpufreq_frequency_table freq_table[];
};
static struct eps_cpu_data *eps_cpu[NR_CPUS];
static unsigned int eps_get(unsigned int cpu)
{
struct eps_cpu_data *centaur;
u32 lo, hi;
if (cpu)
return 0;
centaur = eps_cpu[cpu];
if (centaur == NULL)
return 0;
/* Return current frequency */
rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
return centaur->fsb * ((lo >> 8) & 0xff);
}
static int eps_set_state(struct eps_cpu_data *centaur,
unsigned int cpu,
u32 dest_state)
{
struct cpufreq_freqs freqs;
u32 lo, hi;
int err = 0;
int i;
freqs.old = eps_get(cpu);
freqs.new = centaur->fsb * ((dest_state >> 8) & 0xff);
freqs.cpu = cpu;
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
/* Wait while CPU is busy */
rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
i = 0;
while (lo & ((1 << 16) | (1 << 17))) {
udelay(16);
rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
i++;
if (unlikely(i > 64)) {
err = -ENODEV;
goto postchange;
}
}
/* Set new multiplier and voltage */
wrmsr(MSR_IA32_PERF_CTL, dest_state & 0xffff, 0);
/* Wait until transition end */
i = 0;
do {
udelay(16);
rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
i++;
if (unlikely(i > 64)) {
err = -ENODEV;
goto postchange;
}
} while (lo & ((1 << 16) | (1 << 17)));
/* Return current frequency */
postchange:
rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
freqs.new = centaur->fsb * ((lo >> 8) & 0xff);
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
return err;
}
static int eps_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
struct eps_cpu_data *centaur;
unsigned int newstate = 0;
unsigned int cpu = policy->cpu;
unsigned int dest_state;
int ret;
if (unlikely(eps_cpu[cpu] == NULL))
return -ENODEV;
centaur = eps_cpu[cpu];
if (unlikely(cpufreq_frequency_table_target(policy,
&eps_cpu[cpu]->freq_table[0],
target_freq,
relation,
&newstate))) {
return -EINVAL;
}
/* Make frequency transition */
dest_state = centaur->freq_table[newstate].index & 0xffff;
ret = eps_set_state(centaur, cpu, dest_state);
if (ret)
printk(KERN_ERR "eps: Timeout!\n");
return ret;
}
static int eps_verify(struct cpufreq_policy *policy)
{
return cpufreq_frequency_table_verify(policy,
&eps_cpu[policy->cpu]->freq_table[0]);
}
static int eps_cpu_init(struct cpufreq_policy *policy)
{
unsigned int i;
u32 lo, hi;
u64 val;
u8 current_multiplier, current_voltage;
u8 max_multiplier, max_voltage;
u8 min_multiplier, min_voltage;
u8 brand;
u32 fsb;
struct eps_cpu_data *centaur;
struct cpufreq_frequency_table *f_table;
int k, step, voltage;
int ret;
int states;
if (policy->cpu != 0)
return -ENODEV;
/* Check brand */
printk("eps: Detected VIA ");
rdmsr(0x1153, lo, hi);
brand = (((lo >> 2) ^ lo) >> 18) & 3;
switch(brand) {
case EPS_BRAND_C7M:
printk("C7-M\n");
break;
case EPS_BRAND_C7:
printk("C7\n");
break;
case EPS_BRAND_EDEN:
printk("Eden\n");
break;
case EPS_BRAND_C3:
printk("C3\n");
return -ENODEV;
break;
}
/* Enable Enhanced PowerSaver */
rdmsrl(MSR_IA32_MISC_ENABLE, val);
if (!(val & 1 << 16)) {
val |= 1 << 16;
wrmsrl(MSR_IA32_MISC_ENABLE, val);
/* Can be locked at 0 */
rdmsrl(MSR_IA32_MISC_ENABLE, val);
if (!(val & 1 << 16)) {
printk("eps: Can't enable Enhanced PowerSaver\n");
return -ENODEV;
}
}
/* Print voltage and multiplier */
rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
current_voltage = lo & 0xff;
printk("eps: Current voltage = %dmV\n", current_voltage * 16 + 700);
current_multiplier = (lo >> 8) & 0xff;
printk("eps: Current multiplier = %d\n", current_multiplier);
/* Print limits */
max_voltage = hi & 0xff;
printk("eps: Highest voltage = %dmV\n", max_voltage * 16 + 700);
max_multiplier = (hi >> 8) & 0xff;
printk("eps: Highest multiplier = %d\n", max_multiplier);
min_voltage = (hi >> 16) & 0xff;
printk("eps: Lowest voltage = %dmV\n", min_voltage * 16 + 700);
min_multiplier = (hi >> 24) & 0xff;
printk("eps: Lowest multiplier = %d\n", min_multiplier);
/* Sanity checks */
if (current_multiplier == 0 || max_multiplier == 0
|| min_multiplier == 0)
return -EINVAL;
if (current_multiplier > max_multiplier
|| max_multiplier <= min_multiplier)
return -EINVAL;
if (current_voltage > 0x1c || max_voltage > 0x1c)
return -EINVAL;
if (max_voltage < min_voltage)
return -EINVAL;
/* Calc FSB speed */
fsb = cpu_khz / current_multiplier;
/* Calc number of p-states supported */
if (brand == EPS_BRAND_C7M)
states = max_multiplier - min_multiplier + 1;
else
states = 2;
/* Allocate private data and frequency table for current cpu */
centaur = kzalloc(sizeof(struct eps_cpu_data)
+ (states + 1) * sizeof(struct cpufreq_frequency_table),
GFP_KERNEL);
if (!centaur)
return -ENOMEM;
eps_cpu[0] = centaur;
/* Copy basic values */
centaur->fsb = fsb;
/* Fill frequency and MSR value table */
f_table = &centaur->freq_table[0];
if (brand != EPS_BRAND_C7M) {
f_table[0].frequency = fsb * min_multiplier;
f_table[0].index = (min_multiplier << 8) | min_voltage;
f_table[1].frequency = fsb * max_multiplier;
f_table[1].index = (max_multiplier << 8) | max_voltage;
f_table[2].frequency = CPUFREQ_TABLE_END;
} else {
k = 0;
step = ((max_voltage - min_voltage) * 256)
/ (max_multiplier - min_multiplier);
for (i = min_multiplier; i <= max_multiplier; i++) {
voltage = (k * step) / 256 + min_voltage;
f_table[k].frequency = fsb * i;
f_table[k].index = (i << 8) | voltage;
k++;
}
f_table[k].frequency = CPUFREQ_TABLE_END;
}
policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
policy->cpuinfo.transition_latency = 140000; /* 844mV -> 700mV in ns */
policy->cur = fsb * current_multiplier;
ret = cpufreq_frequency_table_cpuinfo(policy, &centaur->freq_table[0]);
if (ret) {
kfree(centaur);
return ret;
}
cpufreq_frequency_table_get_attr(&centaur->freq_table[0], policy->cpu);
return 0;
}
static int eps_cpu_exit(struct cpufreq_policy *policy)
{
unsigned int cpu = policy->cpu;
struct eps_cpu_data *centaur;
u32 lo, hi;
if (eps_cpu[cpu] == NULL)
return -ENODEV;
centaur = eps_cpu[cpu];
/* Get max frequency */
rdmsr(MSR_IA32_PERF_STATUS, lo, hi);
/* Set max frequency */
eps_set_state(centaur, cpu, hi & 0xffff);
/* Bye */
cpufreq_frequency_table_put_attr(policy->cpu);
kfree(eps_cpu[cpu]);
eps_cpu[cpu] = NULL;
return 0;
}
static struct freq_attr* eps_attr[] = {
&cpufreq_freq_attr_scaling_available_freqs,
NULL,
};
static struct cpufreq_driver eps_driver = {
.verify = eps_verify,
.target = eps_target,
.init = eps_cpu_init,
.exit = eps_cpu_exit,
.get = eps_get,
.name = "e_powersaver",
.owner = THIS_MODULE,
.attr = eps_attr,
};
static int __init eps_init(void)
{
struct cpuinfo_x86 *c = cpu_data;
/* This driver will work only on Centaur C7 processors with
* Enhanced SpeedStep/PowerSaver registers */
if (c->x86_vendor != X86_VENDOR_CENTAUR
|| c->x86 != 6 || c->x86_model != 10)
return -ENODEV;
if (!cpu_has(c, X86_FEATURE_EST))
return -ENODEV;
if (cpufreq_register_driver(&eps_driver))
return -EINVAL;
return 0;
}
static void __exit eps_exit(void)
{
cpufreq_unregister_driver(&eps_driver);
}
MODULE_AUTHOR("Rafa³ Bilski <rafalbilski@interia.pl>");
MODULE_DESCRIPTION("Enhanced PowerSaver driver for VIA C7 CPU's.");
MODULE_LICENSE("GPL");
module_init(eps_init);
module_exit(eps_exit);

361
arch/i386/kernel/cpu/cpufreq/longhaul.c
Просмотреть файл

@ -8,12 +8,11 @@
* VIA have currently 3 different versions of Longhaul.
* Version 1 (Longhaul) uses the BCR2 MSR at 0x1147.
* It is present only in Samuel 1 (C5A), Samuel 2 (C5B) stepping 0.
* Version 2 of longhaul is the same as v1, but adds voltage scaling.
* Present in Samuel 2 (steppings 1-7 only) (C5B), and Ezra (C5C)
* voltage scaling support has currently been disabled in this driver
* until we have code that gets it right.
* Version 2 of longhaul is backward compatible with v1, but adds
* LONGHAUL MSR for purpose of both frequency and voltage scaling.
* Present in Samuel 2 (steppings 1-7 only) (C5B), and Ezra (C5C).
* Version 3 of longhaul got renamed to Powersaver and redesigned
* to use the POWERSAVER MSR at 0x110a.
* to use only the POWERSAVER MSR at 0x110a.
* It is present in Ezra-T (C5M), Nehemiah (C5X) and above.
* It's pretty much the same feature wise to longhaul v2, though
* there is provision for scaling FSB too, but this doesn't work
@ -51,10 +50,12 @@
#define CPU_EZRA 3
#define CPU_EZRA_T 4
#define CPU_NEHEMIAH 5
#define CPU_NEHEMIAH_C 6
/* Flags */
#define USE_ACPI_C3 (1 << 1)
#define USE_NORTHBRIDGE (1 << 2)
#define USE_VT8235 (1 << 3)
static int cpu_model;
static unsigned int numscales=16;
@ -63,7 +64,8 @@ static unsigned int fsb;
static struct mV_pos *vrm_mV_table;
static unsigned char *mV_vrm_table;
struct f_msr {
unsigned char vrm;
u8 vrm;
u8 pos;
};
static struct f_msr f_msr_table[32];
@ -73,10 +75,10 @@ static int can_scale_voltage;
static struct acpi_processor *pr = NULL;
static struct acpi_processor_cx *cx = NULL;
static u8 longhaul_flags;
static u8 longhaul_pos;
/* Module parameters */
static int scale_voltage;
static int ignore_latency;
#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "longhaul", msg)
@ -164,26 +166,47 @@ static void do_longhaul1(unsigned int clock_ratio_index)
static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
{
union msr_longhaul longhaul;
u8 dest_pos;
u32 t;
dest_pos = f_msr_table[clock_ratio_index].pos;
rdmsrl(MSR_VIA_LONGHAUL, longhaul.val);
/* Setup new frequency */
longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
longhaul.bits.SoftBusRatio = clock_ratio_index & 0xf;
longhaul.bits.SoftBusRatio4 = (clock_ratio_index & 0x10) >> 4;
longhaul.bits.EnableSoftBusRatio = 1;
if (can_scale_voltage) {
/* Setup new voltage */
if (can_scale_voltage)
longhaul.bits.SoftVID = f_msr_table[clock_ratio_index].vrm;
longhaul.bits.EnableSoftVID = 1;
}
/* Sync to timer tick */
safe_halt();
/* Raise voltage if necessary */
if (can_scale_voltage && longhaul_pos < dest_pos) {
longhaul.bits.EnableSoftVID = 1;
wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
/* Change voltage */
if (!cx_address) {
ACPI_FLUSH_CPU_CACHE();
halt();
} else {
ACPI_FLUSH_CPU_CACHE();
/* Invoke C3 */
inb(cx_address);
/* Dummy op - must do something useless after P_LVL3
* read */
t = inl(acpi_gbl_FADT.xpm_timer_block.address);
}
longhaul.bits.EnableSoftVID = 0;
wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
longhaul_pos = dest_pos;
}
/* Change frequency on next halt or sleep */
longhaul.bits.EnableSoftBusRatio = 1;
wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
if (!cx_address) {
ACPI_FLUSH_CPU_CACHE();
/* Invoke C1 */
halt();
} else {
ACPI_FLUSH_CPU_CACHE();
@ -193,12 +216,29 @@ static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
t = inl(acpi_gbl_FADT.xpm_timer_block.address);
}
/* Disable bus ratio bit */
local_irq_disable();
longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
longhaul.bits.EnableSoftBusRatio = 0;
longhaul.bits.EnableSoftBSEL = 0;
longhaul.bits.EnableSoftVID = 0;
wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
/* Reduce voltage if necessary */
if (can_scale_voltage && longhaul_pos > dest_pos) {
longhaul.bits.EnableSoftVID = 1;
wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
/* Change voltage */
if (!cx_address) {
ACPI_FLUSH_CPU_CACHE();
halt();
} else {
ACPI_FLUSH_CPU_CACHE();
/* Invoke C3 */
inb(cx_address);
/* Dummy op - must do something useless after P_LVL3
* read */
t = inl(acpi_gbl_FADT.xpm_timer_block.address);
}
longhaul.bits.EnableSoftVID = 0;
wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
longhaul_pos = dest_pos;
}
}
/**
@ -257,26 +297,19 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
/*
* Longhaul v1. (Samuel[C5A] and Samuel2 stepping 0[C5B])
* Software controlled multipliers only.
*
* *NB* Until we get voltage scaling working v1 & v2 are the same code.
* Longhaul v2 appears in Samuel2 Steppings 1->7 [C5b] and Ezra [C5C]
*/
case TYPE_LONGHAUL_V1:
case TYPE_LONGHAUL_V2:
do_longhaul1(clock_ratio_index);
break;
/*
* Longhaul v2 appears in Samuel2 Steppings 1->7 [C5B] and Ezra [C5C]
*
* Longhaul v3 (aka Powersaver). (Ezra-T [C5M] & Nehemiah [C5N])
* We can scale voltage with this too, but that's currently
* disabled until we come up with a decent 'match freq to voltage'
* algorithm.
* When we add voltage scaling, we will also need to do the
* voltage/freq setting in order depending on the direction
* of scaling (like we do in powernow-k7.c)
* Nehemiah can do FSB scaling too, but this has never been proven
* to work in practice.
*/
case TYPE_LONGHAUL_V2:
case TYPE_POWERSAVER:
if (longhaul_flags & USE_ACPI_C3) {
/* Don't allow wakeup */
@ -301,6 +334,7 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
local_irq_restore(flags);
preempt_enable();
freqs.new = calc_speed(longhaul_get_cpu_mult());
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
}
@ -315,31 +349,19 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
#define ROUNDING 0xf
static int _guess(int guess, int mult)
{
int target;
target = ((mult/10)*guess);
if (mult%10 != 0)
target += (guess/2);
target += ROUNDING/2;
target &= ~ROUNDING;
return target;
}
static int guess_fsb(int mult)
{
int speed = (cpu_khz/1000);
int speed = cpu_khz / 1000;
int i;
int speeds[] = { 66, 100, 133, 200 };
int speeds[] = { 666, 1000, 1333, 2000 };
int f_max, f_min;
speed += ROUNDING/2;
speed &= ~ROUNDING;
for (i=0; i<4; i++) {
if (_guess(speeds[i], mult) == speed)
return speeds[i];
for (i = 0; i < 4; i++) {
f_max = ((speeds[i] * mult) + 50) / 100;
f_max += (ROUNDING / 2);
f_min = f_max - ROUNDING;
if ((speed <= f_max) && (speed >= f_min))
return speeds[i] / 10;
}
return 0;
}
@ -347,67 +369,40 @@ static int guess_fsb(int mult)
static int __init longhaul_get_ranges(void)
{
unsigned long invalue;
unsigned int ezra_t_multipliers[32]= {
90, 30, 40, 100, 55, 35, 45, 95,
50, 70, 80, 60, 120, 75, 85, 65,
-1, 110, 120, -1, 135, 115, 125, 105,
130, 150, 160, 140, -1, 155, -1, 145 };
unsigned int j, k = 0;
union msr_longhaul longhaul;
int mult = 0;
int mult;
switch (longhaul_version) {
case TYPE_LONGHAUL_V1:
case TYPE_LONGHAUL_V2:
/* Ugh, Longhaul v1 didn't have the min/max MSRs.
Assume min=3.0x & max = whatever we booted at. */
minmult = 30;
maxmult = mult = longhaul_get_cpu_mult();
break;
case TYPE_POWERSAVER:
/* Ezra-T */
if (cpu_model==CPU_EZRA_T) {
minmult = 30;
rdmsrl (MSR_VIA_LONGHAUL, longhaul.val);
invalue = longhaul.bits.MaxMHzBR;
if (longhaul.bits.MaxMHzBR4)
invalue += 16;
maxmult = mult = ezra_t_multipliers[invalue];
break;
}
/* Nehemiah */
if (cpu_model==CPU_NEHEMIAH) {
rdmsrl (MSR_VIA_LONGHAUL, longhaul.val);
/*
* TODO: This code works, but raises a lot of questions.
* - Some Nehemiah's seem to have broken Min/MaxMHzBR's.
* We get around this by using a hardcoded multiplier of 4.0x
* for the minimimum speed, and the speed we booted up at for the max.
* This is done in longhaul_get_cpu_mult() by reading the EBLCR register.
* - According to some VIA documentation EBLCR is only
* in pre-Nehemiah C3s. How this still works is a mystery.
* We're possibly using something undocumented and unsupported,
* But it works, so we don't grumble.
*/
minmult=40;
maxmult = mult = longhaul_get_cpu_mult();
break;
}
/* Get current frequency */
mult = longhaul_get_cpu_mult();
if (mult == -1) {
printk(KERN_INFO PFX "Invalid (reserved) multiplier!\n");
return -EINVAL;
}
fsb = guess_fsb(mult);
if (fsb == 0) {
printk(KERN_INFO PFX "Invalid (reserved) FSB!\n");
return -EINVAL;
}
/* Get max multiplier - as we always did.
* Longhaul MSR is usefull only when voltage scaling is enabled.
* C3 is booting at max anyway. */
maxmult = mult;
/* Get min multiplier */
switch (cpu_model) {
case CPU_NEHEMIAH:
minmult = 50;
break;
case CPU_NEHEMIAH_C:
minmult = 40;
break;
default:
minmult = 30;
break;
}
dprintk ("MinMult:%d.%dx MaxMult:%d.%dx\n",
minmult/10, minmult%10, maxmult/10, maxmult%10);
if (fsb == 0) {
printk (KERN_INFO PFX "Invalid (reserved) FSB!\n");
return -EINVAL;
}
highest_speed = calc_speed(maxmult);
lowest_speed = calc_speed(minmult);
dprintk ("FSB:%dMHz Lowest speed: %s Highest speed:%s\n", fsb,
@ -455,6 +450,7 @@ static void __init longhaul_setup_voltagescaling(void)
union msr_longhaul longhaul;
struct mV_pos minvid, maxvid;
unsigned int j, speed, pos, kHz_step, numvscales;
int min_vid_speed;
rdmsrl(MSR_VIA_LONGHAUL, longhaul.val);
if (!(longhaul.bits.RevisionID & 1)) {
@ -468,14 +464,14 @@ static void __init longhaul_setup_voltagescaling(void)
mV_vrm_table = &mV_vrm85[0];
} else {
printk (KERN_INFO PFX "Mobile VRM\n");
if (cpu_model < CPU_NEHEMIAH)
return;
vrm_mV_table = &mobilevrm_mV[0];
mV_vrm_table = &mV_mobilevrm[0];
}
minvid = vrm_mV_table[longhaul.bits.MinimumVID];
maxvid = vrm_mV_table[longhaul.bits.MaximumVID];
numvscales = maxvid.pos - minvid.pos + 1;
kHz_step = (highest_speed - lowest_speed) / numvscales;
if (minvid.mV == 0 || maxvid.mV == 0 || minvid.mV > maxvid.mV) {
printk (KERN_INFO PFX "Bogus values Min:%d.%03d Max:%d.%03d. "
@ -491,20 +487,59 @@ static void __init longhaul_setup_voltagescaling(void)
return;
}
printk(KERN_INFO PFX "Max VID=%d.%03d Min VID=%d.%03d, %d possible voltage scales\n",
/* How many voltage steps */
numvscales = maxvid.pos - minvid.pos + 1;
printk(KERN_INFO PFX
"Max VID=%d.%03d "
"Min VID=%d.%03d, "
"%d possible voltage scales\n",
maxvid.mV/1000, maxvid.mV%1000,
minvid.mV/1000, minvid.mV%1000,
numvscales);
/* Calculate max frequency at min voltage */
j = longhaul.bits.MinMHzBR;
if (longhaul.bits.MinMHzBR4)
j += 16;
min_vid_speed = eblcr_table[j];
if (min_vid_speed == -1)
return;
switch (longhaul.bits.MinMHzFSB) {
case 0:
min_vid_speed *= 13333;
break;
case 1:
min_vid_speed *= 10000;
break;
case 3:
min_vid_speed *= 6666;
break;
default:
return;
break;
}
if (min_vid_speed >= highest_speed)
return;
/* Calculate kHz for one voltage step */
kHz_step = (highest_speed - min_vid_speed) / numvscales;
j = 0;
while (longhaul_table[j].frequency != CPUFREQ_TABLE_END) {
speed = longhaul_table[j].frequency;
pos = (speed - lowest_speed) / kHz_step + minvid.pos;
if (speed > min_vid_speed)
pos = (speed - min_vid_speed) / kHz_step + minvid.pos;
else
pos = minvid.pos;
f_msr_table[longhaul_table[j].index].vrm = mV_vrm_table[pos];
f_msr_table[longhaul_table[j].index].pos = pos;
j++;
}
longhaul_pos = maxvid.pos;
can_scale_voltage = 1;
printk(KERN_INFO PFX "Voltage scaling enabled. "
"Use of \"conservative\" governor is highly recommended.\n");
}
@ -573,20 +608,51 @@ static int enable_arbiter_disable(void)
if (dev != NULL) {
/* Enable access to port 0x22 */
pci_read_config_byte(dev, reg, &pci_cmd);
if ( !(pci_cmd & 1<<7) ) {
if (!(pci_cmd & 1<<7)) {
pci_cmd |= 1<<7;
pci_write_config_byte(dev, reg, pci_cmd);
pci_read_config_byte(dev, reg, &pci_cmd);
if (!(pci_cmd & 1<<7)) {
printk(KERN_ERR PFX
"Can't enable access to port 0x22.\n");
return 0;
}
}
return 1;
}
return 0;
}
static int longhaul_setup_vt8235(void)
{
struct pci_dev *dev;
u8 pci_cmd;
/* Find VT8235 southbridge */
dev = pci_find_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235, NULL);
if (dev != NULL) {
/* Set transition time to max */
pci_read_config_byte(dev, 0xec, &pci_cmd);
pci_cmd &= ~(1 << 2);
pci_write_config_byte(dev, 0xec, pci_cmd);
pci_read_config_byte(dev, 0xe4, &pci_cmd);
pci_cmd &= ~(1 << 7);
pci_write_config_byte(dev, 0xe4, pci_cmd);
pci_read_config_byte(dev, 0xe5, &pci_cmd);
pci_cmd |= 1 << 7;
pci_write_config_byte(dev, 0xe5, pci_cmd);
return 1;
}
return 0;
}
static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
{
struct cpuinfo_x86 *c = cpu_data;
char *cpuname=NULL;
int ret;
u32 lo, hi;
int vt8235_present;
/* Check what we have on this motherboard */
switch (c->x86_model) {
@ -599,16 +665,20 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
break;
case 7:
longhaul_version = TYPE_LONGHAUL_V1;
switch (c->x86_mask) {
case 0:
longhaul_version = TYPE_LONGHAUL_V1;
cpu_model = CPU_SAMUEL2;
cpuname = "C3 'Samuel 2' [C5B]";
/* Note, this is not a typo, early Samuel2's had Samuel1 ratios. */
memcpy (clock_ratio, samuel1_clock_ratio, sizeof(samuel1_clock_ratio));
memcpy (eblcr_table, samuel2_eblcr, sizeof(samuel2_eblcr));
/* Note, this is not a typo, early Samuel2's had
* Samuel1 ratios. */
memcpy(clock_ratio, samuel1_clock_ratio,
sizeof(samuel1_clock_ratio));
memcpy(eblcr_table, samuel2_eblcr,
sizeof(samuel2_eblcr));
break;
case 1 ... 15:
longhaul_version = TYPE_LONGHAUL_V2;
if (c->x86_mask < 8) {
cpu_model = CPU_SAMUEL2;
cpuname = "C3 'Samuel 2' [C5B]";
@ -616,8 +686,10 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
cpu_model = CPU_EZRA;
cpuname = "C3 'Ezra' [C5C]";
}
memcpy (clock_ratio, ezra_clock_ratio, sizeof(ezra_clock_ratio));
memcpy (eblcr_table, ezra_eblcr, sizeof(ezra_eblcr));
memcpy(clock_ratio, ezra_clock_ratio,
sizeof(ezra_clock_ratio));
memcpy(eblcr_table, ezra_eblcr,
sizeof(ezra_eblcr));
break;
}
break;
@ -632,24 +704,24 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
break;
case 9:
cpu_model = CPU_NEHEMIAH;
longhaul_version = TYPE_POWERSAVER;
numscales=32;
numscales = 32;
memcpy(clock_ratio,
nehemiah_clock_ratio,
sizeof(nehemiah_clock_ratio));
memcpy(eblcr_table, nehemiah_eblcr, sizeof(nehemiah_eblcr));
switch (c->x86_mask) {
case 0 ... 1:
cpuname = "C3 'Nehemiah A' [C5N]";
memcpy (clock_ratio, nehemiah_a_clock_ratio, sizeof(nehemiah_a_clock_ratio));
memcpy (eblcr_table, nehemiah_a_eblcr, sizeof(nehemiah_a_eblcr));
cpu_model = CPU_NEHEMIAH;
cpuname = "C3 'Nehemiah A' [C5XLOE]";
break;
case 2 ... 4:
cpuname = "C3 'Nehemiah B' [C5N]";
memcpy (clock_ratio, nehemiah_b_clock_ratio, sizeof(nehemiah_b_clock_ratio));
memcpy (eblcr_table, nehemiah_b_eblcr, sizeof(nehemiah_b_eblcr));
cpu_model = CPU_NEHEMIAH;
cpuname = "C3 'Nehemiah B' [C5XLOH]";
break;
case 5 ... 15:
cpuname = "C3 'Nehemiah C' [C5N]";
memcpy (clock_ratio, nehemiah_c_clock_ratio, sizeof(nehemiah_c_clock_ratio));
memcpy (eblcr_table, nehemiah_c_eblcr, sizeof(nehemiah_c_eblcr));
cpu_model = CPU_NEHEMIAH_C;
cpuname = "C3 'Nehemiah C' [C5P]";
break;
}
break;
@ -658,6 +730,13 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
cpuname = "Unknown";
break;
}
/* Check Longhaul ver. 2 */
if (longhaul_version == TYPE_LONGHAUL_V2) {
rdmsr(MSR_VIA_LONGHAUL, lo, hi);
if (lo == 0 && hi == 0)
/* Looks like MSR isn't present */
longhaul_version = TYPE_LONGHAUL_V1;
}
printk (KERN_INFO PFX "VIA %s CPU detected. ", cpuname);
switch (longhaul_version) {
@ -670,15 +749,18 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
break;
};
/* Doesn't hurt */
vt8235_present = longhaul_setup_vt8235();
/* Find ACPI data for processor */
acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX,
&longhaul_walk_callback, NULL, (void *)&pr);
acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX, &longhaul_walk_callback,
NULL, (void *)&pr);
/* Check ACPI support for C3 state */
if ((pr != NULL) && (longhaul_version == TYPE_POWERSAVER)) {
if (pr != NULL && longhaul_version != TYPE_LONGHAUL_V1) {
cx = &pr->power.states[ACPI_STATE_C3];
if (cx->address > 0 &&
(cx->latency <= 1000 || ignore_latency != 0) ) {
if (cx->address > 0 && cx->latency <= 1000) {
longhaul_flags |= USE_ACPI_C3;
goto print_support_type;
}
@ -688,8 +770,11 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
longhaul_flags |= USE_NORTHBRIDGE;
goto print_support_type;
}
/* No ACPI C3 or we can't use it */
/* Use VT8235 southbridge if present */
if (longhaul_version == TYPE_POWERSAVER && vt8235_present) {
longhaul_flags |= USE_VT8235;
goto print_support_type;
}
/* Check ACPI support for bus master arbiter disable */
if ((pr == NULL) || !(pr->flags.bm_control)) {
printk(KERN_ERR PFX
@ -698,18 +783,18 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
}
print_support_type:
if (!(longhaul_flags & USE_NORTHBRIDGE)) {
printk (KERN_INFO PFX "Using ACPI support.\n");
} else {
if (longhaul_flags & USE_NORTHBRIDGE)
printk (KERN_INFO PFX "Using northbridge support.\n");
}
else if (longhaul_flags & USE_VT8235)
printk (KERN_INFO PFX "Using VT8235 support.\n");
else
printk (KERN_INFO PFX "Using ACPI support.\n");
ret = longhaul_get_ranges();
if (ret != 0)
return ret;
if ((longhaul_version==TYPE_LONGHAUL_V2 || longhaul_version==TYPE_POWERSAVER) &&
(scale_voltage != 0))
if ((longhaul_version != TYPE_LONGHAUL_V1) && (scale_voltage != 0))
longhaul_setup_voltagescaling();
policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
@ -797,8 +882,6 @@ static void __exit longhaul_exit(void)
module_param (scale_voltage, int, 0644);
MODULE_PARM_DESC(scale_voltage, "Scale voltage of processor");
module_param(ignore_latency, int, 0644);
MODULE_PARM_DESC(ignore_latency, "Skip ACPI C3 latency test");
MODULE_AUTHOR ("Dave Jones <davej@codemonkey.org.uk>");
MODULE_DESCRIPTION ("Longhaul driver for VIA Cyrix processors.");

153
arch/i386/kernel/cpu/cpufreq/longhaul.h
Просмотреть файл

@ -235,49 +235,14 @@ static int __initdata ezrat_eblcr[32] = {
/*
* VIA C3 Nehemiah */
static int __initdata nehemiah_a_clock_ratio[32] = {
static int __initdata nehemiah_clock_ratio[32] = {
100, /* 0000 -> 10.0x */
160, /* 0001 -> 16.0x */
-1, /* 0010 -> RESERVED */
40, /* 0010 -> 4.0x */
90, /* 0011 -> 9.0x */
95, /* 0100 -> 9.5x */
-1, /* 0101 -> RESERVED */
-1, /* 0110 -> RESERVED */
55, /* 0111 -> 5.5x */
60, /* 1000 -> 6.0x */
70, /* 1001 -> 7.0x */
80, /* 1010 -> 8.0x */
50, /* 1011 -> 5.0x */
65, /* 1100 -> 6.5x */
75, /* 1101 -> 7.5x */
85, /* 1110 -> 8.5x */
120, /* 1111 -> 12.0x */
100, /* 0000 -> 10.0x */
-1, /* 0001 -> RESERVED */
120, /* 0010 -> 12.0x */
90, /* 0011 -> 9.0x */
105, /* 0100 -> 10.5x */
115, /* 0101 -> 11.5x */
125, /* 0110 -> 12.5x */
135, /* 0111 -> 13.5x */
140, /* 1000 -> 14.0x */
150, /* 1001 -> 15.0x */
160, /* 1010 -> 16.0x */
130, /* 1011 -> 13.0x */
145, /* 1100 -> 14.5x */
155, /* 1101 -> 15.5x */
-1, /* 1110 -> RESERVED (13.0x) */
120, /* 1111 -> 12.0x */
};
static int __initdata nehemiah_b_clock_ratio[32] = {
100, /* 0000 -> 10.0x */
160, /* 0001 -> 16.0x */
-1, /* 0010 -> RESERVED */
90, /* 0011 -> 9.0x */
95, /* 0100 -> 9.5x */
-1, /* 0101 -> RESERVED */
-1, /* 0110 -> RESERVED */
45, /* 0110 -> 4.5x */
55, /* 0111 -> 5.5x */
60, /* 1000 -> 6.0x */
70, /* 1001 -> 7.0x */
@ -305,84 +270,14 @@ static int __initdata nehemiah_b_clock_ratio[32] = {
120, /* 1111 -> 12.0x */
};
static int __initdata nehemiah_c_clock_ratio[32] = {
100, /* 0000 -> 10.0x */
160, /* 0001 -> 16.0x */
40, /* 0010 -> RESERVED */
90, /* 0011 -> 9.0x */
95, /* 0100 -> 9.5x */
-1, /* 0101 -> RESERVED */
45, /* 0110 -> RESERVED */
55, /* 0111 -> 5.5x */
60, /* 1000 -> 6.0x */
70, /* 1001 -> 7.0x */
80, /* 1010 -> 8.0x */
50, /* 1011 -> 5.0x */
65, /* 1100 -> 6.5x */
75, /* 1101 -> 7.5x */
85, /* 1110 -> 8.5x */
120, /* 1111 -> 12.0x */
100, /* 0000 -> 10.0x */
110, /* 0001 -> 11.0x */
120, /* 0010 -> 12.0x */
90, /* 0011 -> 9.0x */
105, /* 0100 -> 10.5x */
115, /* 0101 -> 11.5x */
125, /* 0110 -> 12.5x */
135, /* 0111 -> 13.5x */
140, /* 1000 -> 14.0x */
150, /* 1001 -> 15.0x */
160, /* 1010 -> 16.0x */
130, /* 1011 -> 13.0x */
145, /* 1100 -> 14.5x */
155, /* 1101 -> 15.5x */
-1, /* 1110 -> RESERVED (13.0x) */
120, /* 1111 -> 12.0x */
};
static int __initdata nehemiah_a_eblcr[32] = {
static int __initdata nehemiah_eblcr[32] = {
50, /* 0000 -> 5.0x */
160, /* 0001 -> 16.0x */
-1, /* 0010 -> RESERVED */
40, /* 0010 -> 4.0x */
100, /* 0011 -> 10.0x */
55, /* 0100 -> 5.5x */
-1, /* 0101 -> RESERVED */
-1, /* 0110 -> RESERVED */
95, /* 0111 -> 9.5x */
90, /* 1000 -> 9.0x */
70, /* 1001 -> 7.0x */
80, /* 1010 -> 8.0x */
60, /* 1011 -> 6.0x */
120, /* 1100 -> 12.0x */
75, /* 1101 -> 7.5x */
85, /* 1110 -> 8.5x */
65, /* 1111 -> 6.5x */
90, /* 0000 -> 9.0x */
-1, /* 0001 -> RESERVED */
120, /* 0010 -> 12.0x */
100, /* 0011 -> 10.0x */
135, /* 0100 -> 13.5x */
115, /* 0101 -> 11.5x */
125, /* 0110 -> 12.5x */
105, /* 0111 -> 10.5x */
130, /* 1000 -> 13.0x */
150, /* 1001 -> 15.0x */
160, /* 1010 -> 16.0x */
140, /* 1011 -> 14.0x */
120, /* 1100 -> 12.0x */
155, /* 1101 -> 15.5x */
-1, /* 1110 -> RESERVED (13.0x) */
145 /* 1111 -> 14.5x */
/* end of table */
};
static int __initdata nehemiah_b_eblcr[32] = {
50, /* 0000 -> 5.0x */
160, /* 0001 -> 16.0x */
-1, /* 0010 -> RESERVED */
100, /* 0011 -> 10.0x */
55, /* 0100 -> 5.5x */
-1, /* 0101 -> RESERVED */
-1, /* 0110 -> RESERVED */
45, /* 0110 -> 4.5x */
95, /* 0111 -> 9.5x */
90, /* 1000 -> 9.0x */
70, /* 1001 -> 7.0x */
@ -408,42 +303,6 @@ static int __initdata nehemiah_b_eblcr[32] = {
155, /* 1101 -> 15.5x */
-1, /* 1110 -> RESERVED (13.0x) */
145 /* 1111 -> 14.5x */
/* end of table */
};
static int __initdata nehemiah_c_eblcr[32] = {
50, /* 0000 -> 5.0x */
160, /* 0001 -> 16.0x */
40, /* 0010 -> RESERVED */
100, /* 0011 -> 10.0x */
55, /* 0100 -> 5.5x */
-1, /* 0101 -> RESERVED */
45, /* 0110 -> RESERVED */
95, /* 0111 -> 9.5x */
90, /* 1000 -> 9.0x */
70, /* 1001 -> 7.0x */
80, /* 1010 -> 8.0x */
60, /* 1011 -> 6.0x */
120, /* 1100 -> 12.0x */
75, /* 1101 -> 7.5x */
85, /* 1110 -> 8.5x */
65, /* 1111 -> 6.5x */
90, /* 0000 -> 9.0x */
110, /* 0001 -> 11.0x */
120, /* 0010 -> 12.0x */
100, /* 0011 -> 10.0x */
135, /* 0100 -> 13.5x */
115, /* 0101 -> 11.5x */
125, /* 0110 -> 12.5x */
105, /* 0111 -> 10.5x */
130, /* 1000 -> 13.0x */
150, /* 1001 -> 15.0x */
160, /* 1010 -> 16.0x */
140, /* 1011 -> 14.0x */
120, /* 1100 -> 12.0x */
155, /* 1101 -> 15.5x */
-1, /* 1110 -> RESERVED (13.0x) */
145 /* 1111 -> 14.5x */
/* end of table */
};
/*

6
arch/i386/kernel/cpu/cpufreq/powernow-k8.c
Просмотреть файл

@ -1289,7 +1289,11 @@ static unsigned int powernowk8_get (unsigned int cpu)
if (query_current_values_with_pending_wait(data))
goto out;
khz = find_khz_freq_from_fid(data->currfid);
if (cpu_family == CPU_HW_PSTATE)
khz = find_khz_freq_from_fiddid(data->currfid, data->currdid);
else
khz = find_khz_freq_from_fid(data->currfid);
out:
set_cpus_allowed(current, oldmask);

2
drivers/cpufreq/Kconfig
Просмотреть файл

@ -16,7 +16,7 @@ config CPU_FREQ
if CPU_FREQ
config CPU_FREQ_TABLE
def_tristate m
tristate
config CPU_FREQ_DEBUG
bool "Enable CPUfreq debugging"

258
drivers/cpufreq/cpufreq.c
Просмотреть файл

@ -41,8 +41,67 @@ static struct cpufreq_driver *cpufreq_driver;
static struct cpufreq_policy *cpufreq_cpu_data[NR_CPUS];
static DEFINE_SPINLOCK(cpufreq_driver_lock);
/*
* cpu_policy_rwsem is a per CPU reader-writer semaphore designed to cure
* all cpufreq/hotplug/workqueue/etc related lock issues.
*
* The rules for this semaphore:
* - Any routine that wants to read from the policy structure will
* do a down_read on this semaphore.
* - Any routine that will write to the policy structure and/or may take away
* the policy altogether (eg. CPU hotplug), will hold this lock in write
* mode before doing so.
*
* Additional rules:
* - All holders of the lock should check to make sure that the CPU they
* are concerned with are online after they get the lock.
* - Governor routines that can be called in cpufreq hotplug path should not
* take this sem as top level hotplug notifier handler takes this.
*/
static DEFINE_PER_CPU(int, policy_cpu);
static DEFINE_PER_CPU(struct rw_semaphore, cpu_policy_rwsem);
#define lock_policy_rwsem(mode, cpu) \
int lock_policy_rwsem_##mode \
(int cpu) \
{ \
int policy_cpu = per_cpu(policy_cpu, cpu); \
BUG_ON(policy_cpu == -1); \
down_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \
if (unlikely(!cpu_online(cpu))) { \
up_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \
return -1; \
} \
\
return 0; \
}
lock_policy_rwsem(read, cpu);
EXPORT_SYMBOL_GPL(lock_policy_rwsem_read);
lock_policy_rwsem(write, cpu);
EXPORT_SYMBOL_GPL(lock_policy_rwsem_write);
void unlock_policy_rwsem_read(int cpu)
{
int policy_cpu = per_cpu(policy_cpu, cpu);
BUG_ON(policy_cpu == -1);
up_read(&per_cpu(cpu_policy_rwsem, policy_cpu));
}
EXPORT_SYMBOL_GPL(unlock_policy_rwsem_read);
void unlock_policy_rwsem_write(int cpu)
{
int policy_cpu = per_cpu(policy_cpu, cpu);
BUG_ON(policy_cpu == -1);
up_write(&per_cpu(cpu_policy_rwsem, policy_cpu));
}
EXPORT_SYMBOL_GPL(unlock_policy_rwsem_write);
/* internal prototypes */
static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);
static unsigned int __cpufreq_get(unsigned int cpu);
static void handle_update(struct work_struct *work);
/**
@ -415,12 +474,8 @@ static ssize_t store_##file_name \
if (ret != 1) \
return -EINVAL; \
\
lock_cpu_hotplug(); \
mutex_lock(&policy->lock); \
ret = __cpufreq_set_policy(policy, &new_policy); \
policy->user_policy.object = policy->object; \
mutex_unlock(&policy->lock); \
unlock_cpu_hotplug(); \
\
return ret ? ret : count; \
}
@ -434,7 +489,7 @@ store_one(scaling_max_freq,max);
static ssize_t show_cpuinfo_cur_freq (struct cpufreq_policy * policy,
char *buf)
{
unsigned int cur_freq = cpufreq_get(policy->cpu);
unsigned int cur_freq = __cpufreq_get(policy->cpu);
if (!cur_freq)
return sprintf(buf, "<unknown>");
return sprintf(buf, "%u\n", cur_freq);
@ -479,18 +534,12 @@ static ssize_t store_scaling_governor (struct cpufreq_policy * policy,
&new_policy.governor))
return -EINVAL;
lock_cpu_hotplug();
/* Do not use cpufreq_set_policy here or the user_policy.max
will be wrongly overridden */
mutex_lock(&policy->lock);
ret = __cpufreq_set_policy(policy, &new_policy);
policy->user_policy.policy = policy->policy;
policy->user_policy.governor = policy->governor;
mutex_unlock(&policy->lock);
unlock_cpu_hotplug();
if (ret)
return ret;
@ -595,11 +644,17 @@ static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf)
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
if (lock_policy_rwsem_read(policy->cpu) < 0)
return -EINVAL;
if (fattr->show)
ret = fattr->show(policy, buf);
else
ret = -EIO;
unlock_policy_rwsem_read(policy->cpu);
cpufreq_cpu_put(policy);
return ret;
}
@ -613,11 +668,17 @@ static ssize_t store(struct kobject * kobj, struct attribute * attr,
policy = cpufreq_cpu_get(policy->cpu);
if (!policy)
return -EINVAL;
if (lock_policy_rwsem_write(policy->cpu) < 0)
return -EINVAL;
if (fattr->store)
ret = fattr->store(policy, buf, count);
else
ret = -EIO;
unlock_policy_rwsem_write(policy->cpu);
cpufreq_cpu_put(policy);
return ret;
}
@ -691,8 +752,10 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
policy->cpu = cpu;
policy->cpus = cpumask_of_cpu(cpu);
mutex_init(&policy->lock);
mutex_lock(&policy->lock);
/* Initially set CPU itself as the policy_cpu */
per_cpu(policy_cpu, cpu) = cpu;
lock_policy_rwsem_write(cpu);
init_completion(&policy->kobj_unregister);
INIT_WORK(&policy->update, handle_update);
@ -702,7 +765,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
ret = cpufreq_driver->init(policy);
if (ret) {
dprintk("initialization failed\n");
mutex_unlock(&policy->lock);
unlock_policy_rwsem_write(cpu);
goto err_out;
}
@ -716,6 +779,14 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
*/
managed_policy = cpufreq_cpu_get(j);
if (unlikely(managed_policy)) {
/* Set proper policy_cpu */
unlock_policy_rwsem_write(cpu);
per_cpu(policy_cpu, cpu) = managed_policy->cpu;
if (lock_policy_rwsem_write(cpu) < 0)
goto err_out_driver_exit;
spin_lock_irqsave(&cpufreq_driver_lock, flags);
managed_policy->cpus = policy->cpus;
cpufreq_cpu_data[cpu] = managed_policy;
@ -726,13 +797,13 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
&managed_policy->kobj,
"cpufreq");
if (ret) {
mutex_unlock(&policy->lock);
unlock_policy_rwsem_write(cpu);
goto err_out_driver_exit;
}
cpufreq_debug_enable_ratelimit();
mutex_unlock(&policy->lock);
ret = 0;
unlock_policy_rwsem_write(cpu);
goto err_out_driver_exit; /* call driver->exit() */
}
}
@ -746,7 +817,7 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
ret = kobject_register(&policy->kobj);
if (ret) {
mutex_unlock(&policy->lock);
unlock_policy_rwsem_write(cpu);
goto err_out_driver_exit;
}
/* set up files for this cpu device */
@ -761,8 +832,10 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
spin_lock_irqsave(&cpufreq_driver_lock, flags);
for_each_cpu_mask(j, policy->cpus)
for_each_cpu_mask(j, policy->cpus) {
cpufreq_cpu_data[j] = policy;
per_cpu(policy_cpu, j) = policy->cpu;
}
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
/* symlink affected CPUs */
@ -778,14 +851,14 @@ static int cpufreq_add_dev (struct sys_device * sys_dev)
ret = sysfs_create_link(&cpu_sys_dev->kobj, &policy->kobj,
"cpufreq");
if (ret) {
mutex_unlock(&policy->lock);
unlock_policy_rwsem_write(cpu);
goto err_out_unregister;
}
}
policy->governor = NULL; /* to assure that the starting sequence is
* run in cpufreq_set_policy */
mutex_unlock(&policy->lock);
unlock_policy_rwsem_write(cpu);
/* set default policy */
ret = cpufreq_set_policy(&new_policy);
@ -826,11 +899,13 @@ module_out:
/**
* cpufreq_remove_dev - remove a CPU device
* __cpufreq_remove_dev - remove a CPU device
*
* Removes the cpufreq interface for a CPU device.
* Caller should already have policy_rwsem in write mode for this CPU.
* This routine frees the rwsem before returning.
*/
static int cpufreq_remove_dev (struct sys_device * sys_dev)
static int __cpufreq_remove_dev (struct sys_device * sys_dev)
{
unsigned int cpu = sys_dev->id;
unsigned long flags;
@ -849,6 +924,7 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
if (!data) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
cpufreq_debug_enable_ratelimit();
unlock_policy_rwsem_write(cpu);
return -EINVAL;
}
cpufreq_cpu_data[cpu] = NULL;
@ -865,6 +941,7 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
sysfs_remove_link(&sys_dev->kobj, "cpufreq");
cpufreq_cpu_put(data);
cpufreq_debug_enable_ratelimit();
unlock_policy_rwsem_write(cpu);
return 0;
}
#endif
@ -873,6 +950,7 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
if (!kobject_get(&data->kobj)) {
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
cpufreq_debug_enable_ratelimit();
unlock_policy_rwsem_write(cpu);
return -EFAULT;
}
@ -906,10 +984,10 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
#endif
mutex_lock(&data->lock);
if (cpufreq_driver->target)
__cpufreq_governor(data, CPUFREQ_GOV_STOP);
mutex_unlock(&data->lock);
unlock_policy_rwsem_write(cpu);
kobject_unregister(&data->kobj);
@ -933,6 +1011,18 @@ static int cpufreq_remove_dev (struct sys_device * sys_dev)
}
static int cpufreq_remove_dev (struct sys_device * sys_dev)
{
unsigned int cpu = sys_dev->id;
int retval;
if (unlikely(lock_policy_rwsem_write(cpu)))
BUG();
retval = __cpufreq_remove_dev(sys_dev);
return retval;
}
static void handle_update(struct work_struct *work)
{
struct cpufreq_policy *policy =
@ -980,9 +1070,12 @@ unsigned int cpufreq_quick_get(unsigned int cpu)
unsigned int ret_freq = 0;
if (policy) {
mutex_lock(&policy->lock);
if (unlikely(lock_policy_rwsem_read(cpu)))
return ret_freq;
ret_freq = policy->cur;
mutex_unlock(&policy->lock);
unlock_policy_rwsem_read(cpu);
cpufreq_cpu_put(policy);
}
@ -991,24 +1084,13 @@ unsigned int cpufreq_quick_get(unsigned int cpu)
EXPORT_SYMBOL(cpufreq_quick_get);
/**
* cpufreq_get - get the current CPU frequency (in kHz)
* @cpu: CPU number
*
* Get the CPU current (static) CPU frequency
*/
unsigned int cpufreq_get(unsigned int cpu)
static unsigned int __cpufreq_get(unsigned int cpu)
{
struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
struct cpufreq_policy *policy = cpufreq_cpu_data[cpu];
unsigned int ret_freq = 0;
if (!policy)
return 0;
if (!cpufreq_driver->get)
goto out;
mutex_lock(&policy->lock);
return (ret_freq);
ret_freq = cpufreq_driver->get(cpu);
@ -1022,11 +1104,33 @@ unsigned int cpufreq_get(unsigned int cpu)
}
}
mutex_unlock(&policy->lock);
return (ret_freq);
}
out:
/**
* cpufreq_get - get the current CPU frequency (in kHz)
* @cpu: CPU number
*
* Get the CPU current (static) CPU frequency
*/
unsigned int cpufreq_get(unsigned int cpu)
{
unsigned int ret_freq = 0;
struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
if (!policy)
goto out;
if (unlikely(lock_policy_rwsem_read(cpu)))
goto out_policy;
ret_freq = __cpufreq_get(cpu);
unlock_policy_rwsem_read(cpu);
out_policy:
cpufreq_cpu_put(policy);
out:
return (ret_freq);
}
EXPORT_SYMBOL(cpufreq_get);
@ -1278,7 +1382,6 @@ EXPORT_SYMBOL(cpufreq_unregister_notifier);
*********************************************************************/
/* Must be called with lock_cpu_hotplug held */
int __cpufreq_driver_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
@ -1304,20 +1407,19 @@ int cpufreq_driver_target(struct cpufreq_policy *policy,
if (!policy)
return -EINVAL;
lock_cpu_hotplug();
mutex_lock(&policy->lock);
if (unlikely(lock_policy_rwsem_write(policy->cpu)))
return -EINVAL;
ret = __cpufreq_driver_target(policy, target_freq, relation);
mutex_unlock(&policy->lock);
unlock_cpu_hotplug();
unlock_policy_rwsem_write(policy->cpu);
cpufreq_cpu_put(policy);
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_target);
int cpufreq_driver_getavg(struct cpufreq_policy *policy)
int __cpufreq_driver_getavg(struct cpufreq_policy *policy)
{
int ret = 0;
@ -1325,20 +1427,15 @@ int cpufreq_driver_getavg(struct cpufreq_policy *policy)
if (!policy)
return -EINVAL;
mutex_lock(&policy->lock);
if (cpu_online(policy->cpu) && cpufreq_driver->getavg)
ret = cpufreq_driver->getavg(policy->cpu);
mutex_unlock(&policy->lock);
cpufreq_cpu_put(policy);
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_driver_getavg);
EXPORT_SYMBOL_GPL(__cpufreq_driver_getavg);
/*
* Locking: Must be called with the lock_cpu_hotplug() lock held
* when "event" is CPUFREQ_GOV_LIMITS
*/
@ -1420,9 +1517,7 @@ int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
if (!cpu_policy)
return -EINVAL;
mutex_lock(&cpu_policy->lock);
memcpy(policy, cpu_policy, sizeof(struct cpufreq_policy));
mutex_unlock(&cpu_policy->lock);
cpufreq_cpu_put(cpu_policy);
return 0;
@ -1433,7 +1528,6 @@ EXPORT_SYMBOL(cpufreq_get_policy);
/*
* data : current policy.
* policy : policy to be set.
* Locking: Must be called with the lock_cpu_hotplug() lock held
*/
static int __cpufreq_set_policy(struct cpufreq_policy *data,
struct cpufreq_policy *policy)
@ -1539,10 +1633,9 @@ int cpufreq_set_policy(struct cpufreq_policy *policy)
if (!data)
return -EINVAL;
lock_cpu_hotplug();
if (unlikely(lock_policy_rwsem_write(policy->cpu)))
return -EINVAL;
/* lock this CPU */
mutex_lock(&data->lock);
ret = __cpufreq_set_policy(data, policy);
data->user_policy.min = data->min;
@ -1550,9 +1643,8 @@ int cpufreq_set_policy(struct cpufreq_policy *policy)
data->user_policy.policy = data->policy;
data->user_policy.governor = data->governor;
mutex_unlock(&data->lock);
unlock_policy_rwsem_write(policy->cpu);
unlock_cpu_hotplug();
cpufreq_cpu_put(data);
return ret;
@ -1576,8 +1668,8 @@ int cpufreq_update_policy(unsigned int cpu)
if (!data)
return -ENODEV;
lock_cpu_hotplug();
mutex_lock(&data->lock);
if (unlikely(lock_policy_rwsem_write(cpu)))
return -EINVAL;
dprintk("updating policy for CPU %u\n", cpu);
memcpy(&policy, data, sizeof(struct cpufreq_policy));
@ -1602,8 +1694,8 @@ int cpufreq_update_policy(unsigned int cpu)
ret = __cpufreq_set_policy(data, &policy);
mutex_unlock(&data->lock);
unlock_cpu_hotplug();
unlock_policy_rwsem_write(cpu);
cpufreq_cpu_put(data);
return ret;
}
@ -1613,31 +1705,28 @@ static int cpufreq_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
struct cpufreq_policy *policy;
struct sys_device *sys_dev;
struct cpufreq_policy *policy;
sys_dev = get_cpu_sysdev(cpu);
if (sys_dev) {
switch (action) {
case CPU_ONLINE:
cpufreq_add_dev(sys_dev);
break;
case CPU_DOWN_PREPARE:
/*
* We attempt to put this cpu in lowest frequency
* possible before going down. This will permit
* hardware-managed P-State to switch other related
* threads to min or higher speeds if possible.
*/
if (unlikely(lock_policy_rwsem_write(cpu)))
BUG();
policy = cpufreq_cpu_data[cpu];
if (policy) {
cpufreq_driver_target(policy, policy->min,
__cpufreq_driver_target(policy, policy->min,
CPUFREQ_RELATION_H);
}
__cpufreq_remove_dev(sys_dev);
break;
case CPU_DEAD:
cpufreq_remove_dev(sys_dev);
case CPU_DOWN_FAILED:
cpufreq_add_dev(sys_dev);
break;
}
}
@ -1751,3 +1840,16 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver)
return 0;
}
EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
static int __init cpufreq_core_init(void)
{
int cpu;
for_each_possible_cpu(cpu) {
per_cpu(policy_cpu, cpu) = -1;
init_rwsem(&per_cpu(cpu_policy_rwsem, cpu));
}
return 0;
}
core_initcall(cpufreq_core_init);

2
drivers/cpufreq/cpufreq_conservative.c
Просмотреть файл

@ -429,14 +429,12 @@ static void dbs_check_cpu(int cpu)
static void do_dbs_timer(struct work_struct *work)
{
int i;
lock_cpu_hotplug();
mutex_lock(&dbs_mutex);
for_each_online_cpu(i)
dbs_check_cpu(i);
schedule_delayed_work(&dbs_work,
usecs_to_jiffies(dbs_tuners_ins.sampling_rate));
mutex_unlock(&dbs_mutex);
unlock_cpu_hotplug();
}
static inline void dbs_timer_init(void)

64
drivers/cpufreq/cpufreq_ondemand.c
Просмотреть файл

@ -52,19 +52,20 @@ static unsigned int def_sampling_rate;
static void do_dbs_timer(struct work_struct *work);
/* Sampling types */
enum dbs_sample {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE};
enum {DBS_NORMAL_SAMPLE, DBS_SUB_SAMPLE};
struct cpu_dbs_info_s {
cputime64_t prev_cpu_idle;
cputime64_t prev_cpu_wall;
struct cpufreq_policy *cur_policy;
struct delayed_work work;
enum dbs_sample sample_type;
unsigned int enable;
struct cpufreq_frequency_table *freq_table;
unsigned int freq_lo;
unsigned int freq_lo_jiffies;
unsigned int freq_hi_jiffies;
int cpu;
unsigned int enable:1,
sample_type:1;
};
static DEFINE_PER_CPU(struct cpu_dbs_info_s, cpu_dbs_info);
@ -402,7 +403,7 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
if (load < (dbs_tuners_ins.up_threshold - 10)) {
unsigned int freq_next, freq_cur;
freq_cur = cpufreq_driver_getavg(policy);
freq_cur = __cpufreq_driver_getavg(policy);
if (!freq_cur)
freq_cur = policy->cur;
@ -423,9 +424,11 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
static void do_dbs_timer(struct work_struct *work)
{
unsigned int cpu = smp_processor_id();
struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
enum dbs_sample sample_type = dbs_info->sample_type;
struct cpu_dbs_info_s *dbs_info =
container_of(work, struct cpu_dbs_info_s, work.work);
unsigned int cpu = dbs_info->cpu;
int sample_type = dbs_info->sample_type;
/* We want all CPUs to do sampling nearly on same jiffy */
int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
@ -434,15 +437,19 @@ static void do_dbs_timer(struct work_struct *work)
delay -= jiffies % delay;
if (!dbs_info->enable)
if (lock_policy_rwsem_write(cpu) < 0)
return;
if (!dbs_info->enable) {
unlock_policy_rwsem_write(cpu);
return;
}
/* Common NORMAL_SAMPLE setup */
dbs_info->sample_type = DBS_NORMAL_SAMPLE;
if (!dbs_tuners_ins.powersave_bias ||
sample_type == DBS_NORMAL_SAMPLE) {
lock_cpu_hotplug();
dbs_check_cpu(dbs_info);
unlock_cpu_hotplug();
if (dbs_info->freq_lo) {
/* Setup timer for SUB_SAMPLE */
dbs_info->sample_type = DBS_SUB_SAMPLE;
@ -454,26 +461,27 @@ static void do_dbs_timer(struct work_struct *work)
CPUFREQ_RELATION_H);
}
queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay);
unlock_policy_rwsem_write(cpu);
}
static inline void dbs_timer_init(unsigned int cpu)
static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info)
{
struct cpu_dbs_info_s *dbs_info = &per_cpu(cpu_dbs_info, cpu);
/* We want all CPUs to do sampling nearly on same jiffy */
int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
delay -= jiffies % delay;
dbs_info->enable = 1;
ondemand_powersave_bias_init();
INIT_DELAYED_WORK_NAR(&dbs_info->work, do_dbs_timer);
dbs_info->sample_type = DBS_NORMAL_SAMPLE;
queue_delayed_work_on(cpu, kondemand_wq, &dbs_info->work, delay);
INIT_DELAYED_WORK_NAR(&dbs_info->work, do_dbs_timer);
queue_delayed_work_on(dbs_info->cpu, kondemand_wq, &dbs_info->work,
delay);
}
static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info)
{
dbs_info->enable = 0;
cancel_delayed_work(&dbs_info->work);
flush_workqueue(kondemand_wq);
}
static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
@ -502,21 +510,9 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
mutex_lock(&dbs_mutex);
dbs_enable++;
if (dbs_enable == 1) {
kondemand_wq = create_workqueue("kondemand");
if (!kondemand_wq) {
printk(KERN_ERR
"Creation of kondemand failed\n");
dbs_enable--;
mutex_unlock(&dbs_mutex);
return -ENOSPC;
}
}
rc = sysfs_create_group(&policy->kobj, &dbs_attr_group);
if (rc) {
if (dbs_enable == 1)
destroy_workqueue(kondemand_wq);
dbs_enable--;
mutex_unlock(&dbs_mutex);
return rc;
@ -530,7 +526,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j);
j_dbs_info->prev_cpu_wall = get_jiffies_64();
}
this_dbs_info->enable = 1;
this_dbs_info->cpu = cpu;
/*
* Start the timerschedule work, when this governor
* is used for first time
@ -550,7 +546,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
dbs_tuners_ins.sampling_rate = def_sampling_rate;
}
dbs_timer_init(policy->cpu);
dbs_timer_init(this_dbs_info);
mutex_unlock(&dbs_mutex);
break;
@ -560,9 +556,6 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
dbs_timer_exit(this_dbs_info);
sysfs_remove_group(&policy->kobj, &dbs_attr_group);
dbs_enable--;
if (dbs_enable == 0)
destroy_workqueue(kondemand_wq);
mutex_unlock(&dbs_mutex);
break;
@ -591,12 +584,18 @@ static struct cpufreq_governor cpufreq_gov_dbs = {
static int __init cpufreq_gov_dbs_init(void)
{
kondemand_wq = create_workqueue("kondemand");
if (!kondemand_wq) {
printk(KERN_ERR "Creation of kondemand failed\n");
return -EFAULT;
}
return cpufreq_register_governor(&cpufreq_gov_dbs);
}
static void __exit cpufreq_gov_dbs_exit(void)
{
cpufreq_unregister_governor(&cpufreq_gov_dbs);
destroy_workqueue(kondemand_wq);
}
@ -608,3 +607,4 @@ MODULE_LICENSE("GPL");
module_init(cpufreq_gov_dbs_init);
module_exit(cpufreq_gov_dbs_exit);

2
drivers/cpufreq/cpufreq_stats.c
Просмотреть файл

@ -370,12 +370,10 @@ __exit cpufreq_stats_exit(void)
cpufreq_unregister_notifier(&notifier_trans_block,
CPUFREQ_TRANSITION_NOTIFIER);
unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
lock_cpu_hotplug();
for_each_online_cpu(cpu) {
cpufreq_stat_cpu_callback(&cpufreq_stat_cpu_notifier,
CPU_DEAD, (void *)(long)cpu);
}
unlock_cpu_hotplug();
}
MODULE_AUTHOR ("Zou Nan hai <nanhai.zou@intel.com>");

2
drivers/cpufreq/cpufreq_userspace.c
Просмотреть файл

@ -71,7 +71,6 @@ static int cpufreq_set(unsigned int freq, struct cpufreq_policy *policy)
dprintk("cpufreq_set for cpu %u, freq %u kHz\n", policy->cpu, freq);
lock_cpu_hotplug();
mutex_lock(&userspace_mutex);
if (!cpu_is_managed[policy->cpu])
goto err;
@ -94,7 +93,6 @@ static int cpufreq_set(unsigned int freq, struct cpufreq_policy *policy)
err:
mutex_unlock(&userspace_mutex);
unlock_cpu_hotplug();
return ret;
}

10
include/linux/cpufreq.h
Просмотреть файл

@ -84,9 +84,6 @@ struct cpufreq_policy {
unsigned int policy; /* see above */
struct cpufreq_governor *governor; /* see below */
struct mutex lock; /* CPU ->setpolicy or ->target may
only be called once a time */
struct work_struct update; /* if update_policy() needs to be
* called, but you're in IRQ context */
@ -172,11 +169,16 @@ extern int __cpufreq_driver_target(struct cpufreq_policy *policy,
unsigned int relation);
extern int cpufreq_driver_getavg(struct cpufreq_policy *policy);
extern int __cpufreq_driver_getavg(struct cpufreq_policy *policy);
int cpufreq_register_governor(struct cpufreq_governor *governor);
void cpufreq_unregister_governor(struct cpufreq_governor *governor);
int lock_policy_rwsem_read(int cpu);
int lock_policy_rwsem_write(int cpu);
void unlock_policy_rwsem_read(int cpu);
void unlock_policy_rwsem_write(int cpu);
/*********************************************************************
* CPUFREQ DRIVER INTERFACE *