*/
#include <linux/kernel.h>
-#include <linux/module.h>
+#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
/* See table 14 of p3_ds.pdf and table 22 of 29834003.pdf */
struct {
unsigned int ratio; /* Frequency Multiplier (x10) */
- u8 bitmap; /* power on configuration bits
- [27, 25:22] (in MSR 0x2a) */
+ u8 bitmap; /* power on configuration bits
+ [27, 25:22] (in MSR 0x2a) */
} msr_decode_mult [] = {
{ 30, 0x01 },
{ 35, 0x05 },
/* PIII(-M) FSB settings: see table b1-b of 24547206.pdf */
struct {
- unsigned int value; /* Front Side Bus speed in MHz */
- u8 bitmap; /* power on configuration bits [18: 19]
- (in MSR 0x2a) */
+ unsigned int value; /* Front Side Bus speed in MHz */
+ u8 bitmap; /* power on configuration bits [18: 19]
+ (in MSR 0x2a) */
} msr_decode_fsb [] = {
{ 66, 0x0 },
{ 100, 0x2 },
{ 0, 0xff}
};
- u32 msr_lo, msr_tmp;
- int i = 0, j = 0;
+ u32 msr_lo, msr_tmp;
+ int i = 0, j = 0;
/* read MSR 0x2a - we only need the low 32 bits */
rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_tmp);
static unsigned int pentiumM_get_frequency(void)
{
- u32 msr_lo, msr_tmp;
+ u32 msr_lo, msr_tmp;
rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_tmp);
dprintk("PM - MSR_IA32_EBL_CR_POWERON: 0x%x 0x%x\n", msr_lo, msr_tmp);
return (msr_tmp * 100 * 1000);
}
+static unsigned int pentium_core_get_frequency(void)
+{
+ u32 fsb = 0;
+ u32 msr_lo, msr_tmp;
+
+ rdmsr(MSR_FSB_FREQ, msr_lo, msr_tmp);
+ /* see table B-2 of 25366920.pdf */
+ switch (msr_lo & 0x07) {
+ case 5:
+ fsb = 100000;
+ break;
+ case 1:
+ fsb = 133333;
+ break;
+ case 3:
+ fsb = 166667;
+ break;
+ default:
+ printk(KERN_ERR "PCORE - MSR_FSB_FREQ undefined value");
+ }
+
+ rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_tmp);
+ dprintk("PCORE - MSR_IA32_EBL_CR_POWERON: 0x%x 0x%x\n", msr_lo, msr_tmp);
+
+ msr_tmp = (msr_lo >> 22) & 0x1f;
+ dprintk("bits 22-26 are 0x%x, speed is %u\n", msr_tmp, (msr_tmp * fsb));
+
+ return (msr_tmp * fsb);
+}
+
static unsigned int pentium4_get_frequency(void)
{
dprintk("P4 - MSR_EBC_FREQUENCY_ID: 0x%x 0x%x\n", msr_lo, msr_hi);
- /* decode the FSB: see IA-32 Intel (C) Architecture Software
+ /* decode the FSB: see IA-32 Intel (C) Architecture Software
* Developer's Manual, Volume 3: System Prgramming Guide,
* revision #12 in Table B-1: MSRs in the Pentium 4 and
* Intel Xeon Processors, on page B-4 and B-5.
printk(KERN_DEBUG "speedstep-lib: couldn't detect FSB speed. Please send an e-mail to <linux@brodo.de>\n");
/* Multiplier. */
- mult = msr_lo >> 24;
+ if (c->x86_model < 2)
+ mult = msr_lo >> 27;
+ else
+ mult = msr_lo >> 24;
dprintk("P4 - FSB %u kHz; Multiplier %u; Speed %u kHz\n", fsb, mult, (fsb * mult));
return (fsb * mult);
}
-
+
unsigned int speedstep_get_processor_frequency(unsigned int processor)
{
switch (processor) {
+ case SPEEDSTEP_PROCESSOR_PCORE:
+ return pentium_core_get_frequency();
case SPEEDSTEP_PROCESSOR_PM:
return pentiumM_get_frequency();
case SPEEDSTEP_PROCESSOR_P4D:
unsigned int speedstep_detect_processor (void)
{
struct cpuinfo_x86 *c = cpu_data;
- u32 ebx, msr_lo, msr_hi;
+ u32 ebx, msr_lo, msr_hi;
dprintk("x86: %x, model: %x\n", c->x86, c->x86_model);
- if ((c->x86_vendor != X86_VENDOR_INTEL) ||
+ if ((c->x86_vendor != X86_VENDOR_INTEL) ||
((c->x86 != 6) && (c->x86 != 0xF)))
return 0;
dprintk("ebx value is %x, x86_mask is %x\n", ebx, c->x86_mask);
switch (c->x86_mask) {
- case 4:
+ case 4:
/*
- * B-stepping [M-P4-M]
+ * B-stepping [M-P4-M]
* sample has ebx = 0x0f, production has 0x0e.
*/
if ((ebx == 0x0e) || (ebx == 0x0f))
return SPEEDSTEP_PROCESSOR_P4M;
break;
- case 7:
+ case 7:
/*
* C-stepping [M-P4-M]
* needs to have ebx=0x0e, else it's a celeron:
* also, M-P4M HTs have ebx=0x8, too
* For now, they are distinguished by the model_id string
*/
- if ((ebx == 0x0e) || (strstr(c->x86_model_id,"Mobile Intel(R) Pentium(R) 4") != NULL))
+ if ((ebx == 0x0e) || (strstr(c->x86_model_id,"Mobile Intel(R) Pentium(R) 4") != NULL))
return SPEEDSTEP_PROCESSOR_P4M;
break;
default:
switch (c->x86_model) {
case 0x0B: /* Intel PIII [Tualatin] */
- /* cpuid_ebx(1) is 0x04 for desktop PIII,
- 0x06 for mobile PIII-M */
+ /* cpuid_ebx(1) is 0x04 for desktop PIII, 0x06 for mobile PIII-M */
ebx = cpuid_ebx(0x00000001);
dprintk("ebx is %x\n", ebx);
return 0;
/* So far all PIII-M processors support SpeedStep. See
- * Intel's 24540640.pdf of June 2003
+ * Intel's 24540640.pdf of June 2003
*/
-
return SPEEDSTEP_PROCESSOR_PIII_T;
case 0x08: /* Intel PIII [Coppermine] */
unsigned int speedstep_get_freqs(unsigned int processor,
unsigned int *low_speed,
unsigned int *high_speed,
+ unsigned int *transition_latency,
void (*set_state) (unsigned int state))
{
unsigned int prev_speed;
unsigned int ret = 0;
unsigned long flags;
+ struct timeval tv1, tv2;
if ((!processor) || (!low_speed) || (!high_speed) || (!set_state))
return -EINVAL;
if (!prev_speed)
return -EIO;
- dprintk("previous seped is %u\n", prev_speed);
-
+ dprintk("previous speed is %u\n", prev_speed);
+
local_irq_save(flags);
/* switch to low state */
goto out;
}
- dprintk("low seped is %u\n", *low_speed);
+ dprintk("low speed is %u\n", *low_speed);
+
+ /* start latency measurement */
+ if (transition_latency)
+ do_gettimeofday(&tv1);
/* switch to high state */
set_state(SPEEDSTEP_HIGH);
+
+ /* end latency measurement */
+ if (transition_latency)
+ do_gettimeofday(&tv2);
+
*high_speed = speedstep_get_processor_frequency(processor);
if (!*high_speed) {
ret = -EIO;
goto out;
}
- dprintk("high seped is %u\n", *high_speed);
+ dprintk("high speed is %u\n", *high_speed);
if (*low_speed == *high_speed) {
ret = -ENODEV;
if (*high_speed != prev_speed)
set_state(SPEEDSTEP_LOW);
- out:
+ if (transition_latency) {
+ *transition_latency = (tv2.tv_sec - tv1.tv_sec) * USEC_PER_SEC +
+ tv2.tv_usec - tv1.tv_usec;
+ dprintk("transition latency is %u uSec\n", *transition_latency);
+
+ /* convert uSec to nSec and add 20% for safety reasons */
+ *transition_latency *= 1200;
+
+ /* check if the latency measurement is too high or too low
+ * and set it to a safe value (500uSec) in that case
+ */
+ if (*transition_latency > 10000000 || *transition_latency < 50000) {
+ printk (KERN_WARNING "speedstep: frequency transition measured seems out of "
+ "range (%u nSec), falling back to a safe one of %u nSec.\n",
+ *transition_latency, 500000);
+ *transition_latency = 500000;
+ }
+ }
+
+out:
local_irq_restore(flags);
return (ret);
}