[CPUFREQ] speedstep cleanups.

From Dominik Brodowski.

- separate functions which might be useful for speedstep-piix4,
  speedstep-via or speedstep-bios into a new speedstep-lib.c.
- clean up speedstep-ich as it will only be used for ICH-based chipsets
  in future.   
- remove now-obsolete speedstep_coppermine parameter

Documentation/cpu-freq/user-guide.txt

@@ -56,19 +56,15 @@ AMD mobile K6-3+
 AMD mobile Duron
 AMD mobile Athlon
 Cyrix Media GXm
-Intel mobile PIII [*] and Intel mobile PIII-M on certain chipsets
+Intel mobile PIII and Intel mobile PIII-M on certain chipsets
 Intel Pentium 4, Intel Xeon
 Intel Pentium M (Centrino)
 National Semiconductors Geode GX
 Transmeta Crusoe
 VIA Cyrix 3 / C3
-various processors on some ACPI 2.0-compatible systems [**]
+various processors on some ACPI 2.0-compatible systems [*]
 
-[*] only certain Intel mobile PIII processors are supported. If you
-know that you own a speedstep-capable processor, pass the option
-"speedstep_coppermine=1" to the module speedstep.o
-
-[**] Only if "ACPI Processor Performance States" are available
+[*] Only if "ACPI Processor Performance States" are available
 to the ACPI<->BIOS interface.
 
 

arch/i386/kernel/cpu/cpufreq/Kconfig

@@ -123,6 +123,11 @@ config X86_SPEEDSTEP_CENTRINO
 	  
 	  If in doubt, say N.
 
+config X86_SPEEDSTEP_LIB
+       tristate
+       depends on X86_SPEEDSTEP_ICH
+       default X86_SPEEDSTEP_ICH
+
 config X86_P4_CLOCKMOD
 	tristate "Intel Pentium 4 clock modulation"
 	depends on CPU_FREQ_TABLE

arch/i386/kernel/cpu/cpufreq/Makefile

@@ -8,6 +8,7 @@ obj-$(CONFIG_X86_GX_SUSPMOD)    += gx-suspmod.o
 obj-$(CONFIG_X86_ACPI_CPUFREQ)	+= acpi.o
 obj-$(CONFIG_X86_SPEEDSTEP_ICH)	+= speedstep-ich.o
 obj-$(CONFIG_X86_SPEEDSTEP_CENTRINO) += speedstep-centrino.o
+obj-$(CONFIG_X86_SPEEDSTEP_LIB) += speedstep-lib.o
 
 ifdef CONFIG_X86_ACPI_CPUFREQ
   ifdef CONFIG_ACPI_DEBUG

arch/i386/kernel/cpu/cpufreq/speedstep-lib.c

+/*
+ * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
+ *
+ *  Licensed under the terms of the GNU GPL License version 2.
+ *
+ *  Library for common functions for Intel SpeedStep v.1 and v.2 support
+ *
+ *  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/pci.h>
+#include <linux/slab.h>
+
+#include <asm/msr.h>
+#include "speedstep-lib.h"
+
+
+/* DEBUG
+ *   Define it if you want verbose debug output, e.g. for bug reporting
+ */
+//#define SPEEDSTEP_DEBUG
+
+#ifdef SPEEDSTEP_DEBUG
+#define dprintk(msg...) printk(msg)
+#else
+#define dprintk(msg...) do { } while(0)
+#endif
+
+/*********************************************************************
+ *                   GET PROCESSOR CORE SPEED IN KHZ                 *
+ *********************************************************************/
+
+static unsigned int pentium3_get_frequency (unsigned int processor)
+{
+        /* 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) */
+	} msr_decode_mult [] = {
+		{ 30, 0x01 },
+		{ 35, 0x05 },
+		{ 40, 0x02 },
+		{ 45, 0x06 },
+		{ 50, 0x00 },
+		{ 55, 0x04 },
+		{ 60, 0x0b },
+		{ 65, 0x0f },
+		{ 70, 0x09 },
+		{ 75, 0x0d },
+		{ 80, 0x0a },
+		{ 85, 0x26 },
+		{ 90, 0x20 },
+		{ 100, 0x2b },
+		{ 0, 0xff }     /* error or unknown value */
+	};
+
+	/* 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) */
+	} msr_decode_fsb [] = {
+		{  66, 0x0 },
+		{ 100, 0x2 },
+		{ 133, 0x1 },
+		{   0, 0xff}
+	};
+
+	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);
+	dprintk(KERN_DEBUG "speedstep-lib: P3 - MSR_IA32_EBL_CR_POWERON: 0x%x 0x%x\n", msr_lo, msr_tmp);
+	msr_tmp = msr_lo;
+
+	/* decode the FSB */
+	msr_tmp &= 0x00c0000;
+	msr_tmp >>= 18;
+	while (msr_tmp != msr_decode_fsb[i].bitmap) {
+		if (msr_decode_fsb[i].bitmap == 0xff)
+			return 0;
+		i++;
+	}
+
+	/* decode the multiplier */
+	if (processor == SPEEDSTEP_PROCESSOR_PIII_C_EARLY)
+		msr_lo &= 0x03c00000;
+	else
+		msr_lo &= 0x0bc00000;
+	msr_lo >>= 22;
+	while (msr_lo != msr_decode_mult[j].bitmap) {
+		if (msr_decode_mult[j].bitmap == 0xff)
+			return 0;
+		j++;
+	}
+
+	return (msr_decode_mult[j].ratio * msr_decode_fsb[i].value * 100);
+}
+
+
+static unsigned int pentium4_get_frequency(void)
+{
+	u32 msr_lo, msr_hi;
+
+	rdmsr(0x2c, msr_lo, msr_hi);
+
+	dprintk(KERN_DEBUG "speedstep-lib: P4 - MSR_EBC_FREQUENCY_ID: 0x%x 0x%x\n", msr_lo, msr_hi);
+
+	msr_lo >>= 24;
+	return (msr_lo * 100000);
+}
+
+ 
+unsigned int speedstep_get_processor_frequency(unsigned int processor)
+{
+	switch (processor) {
+	case SPEEDSTEP_PROCESSOR_P4M:
+		return pentium4_get_frequency();
+	case SPEEDSTEP_PROCESSOR_PIII_T:
+	case SPEEDSTEP_PROCESSOR_PIII_C:
+	case SPEEDSTEP_PROCESSOR_PIII_C_EARLY:
+		return pentium3_get_frequency(processor);
+	default:
+		return 0;
+	};
+	return 0;
+}
+EXPORT_SYMBOL_GPL(speedstep_get_processor_frequency);
+
+
+/*********************************************************************
+ *                 DETECT SPEEDSTEP-CAPABLE PROCESSOR                *
+ *********************************************************************/
+
+unsigned int speedstep_detect_processor (void)
+{
+	struct cpuinfo_x86 *c = cpu_data;
+	u32			ebx, msr_lo, msr_hi;
+
+	if ((c->x86_vendor != X86_VENDOR_INTEL) || 
+	    ((c->x86 != 6) && (c->x86 != 0xF)))
+		return 0;
+
+	if (c->x86 == 0xF) {
+		/* Intel Pentium 4 Mobile P4-M */
+		if (c->x86_model != 2)
+			return 0;
+
+		if ((c->x86_mask != 4) && (c->x86_mask != 7))
+			return 0;
+
+		ebx = cpuid_ebx(0x00000001);
+		ebx &= 0x000000FF;
+		if ((ebx != 0x0e) && (ebx != 0x0f))
+			return 0;
+
+		return SPEEDSTEP_PROCESSOR_P4M;
+	}
+
+	switch (c->x86_model) {
+	case 0x0B: /* Intel PIII [Tualatin] */
+		/* cpuid_ebx(1) is 0x04 for desktop PIII, 
+		                   0x06 for mobile PIII-M */
+		ebx = cpuid_ebx(0x00000001);
+
+		ebx &= 0x000000FF;
+		if (ebx != 0x06)
+			return 0;
+
+		/* So far all PIII-M processors support SpeedStep. See
+		 * Intel's 24540640.pdf of June 2003 
+		 */
+
+		return SPEEDSTEP_PROCESSOR_PIII_T;
+
+	case 0x08: /* Intel PIII [Coppermine] */
+
+		/* all mobile PIII Coppermines have FSB 100 MHz
+		 * ==> sort out a few desktop PIIIs. */
+		rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_hi);
+		dprintk(KERN_DEBUG "cpufreq: Coppermine: MSR_IA32_EBL_CR_POWERON is 0x%x, 0x%x\n", msr_lo, msr_hi);
+		msr_lo &= 0x00c0000;
+		if (msr_lo != 0x0080000)
+			return 0;
+
+		/*
+		 * If the processor is a mobile version,
+		 * platform ID has bit 50 set
+		 * it has SpeedStep technology if either
+		 * bit 56 or 57 is set
+		 */
+		rdmsr(MSR_IA32_PLATFORM_ID, msr_lo, msr_hi);
+		dprintk(KERN_DEBUG "cpufreq: Coppermine: MSR_IA32_PLATFORM ID is 0x%x, 0x%x\n", msr_lo, msr_hi);
+		if ((msr_hi & (1<<18)) && (msr_hi & (3<<24))) {
+			if (c->x86_mask == 0x01)
+				return SPEEDSTEP_PROCESSOR_PIII_C_EARLY;
+			else
+				return SPEEDSTEP_PROCESSOR_PIII_C;
+		}
+
+	default:
+		return 0;
+	}
+}
+EXPORT_SYMBOL_GPL(speedstep_detect_processor);
+
+
+/*********************************************************************
+ *                     DETECT SPEEDSTEP SPEEDS                       *
+ *********************************************************************/
+
+unsigned int speedstep_get_freqs(unsigned int processor,
+				  unsigned int *low_speed,
+				  unsigned int *high_speed,
+				  void (*set_state) (unsigned int state,
+						     unsigned int notify)
+				 )
+{
+	unsigned int prev_speed;
+	unsigned int ret = 0;
+	unsigned long flags;
+
+	if ((!processor) || (!low_speed) || (!high_speed) || (!set_state))
+		return EINVAL;
+
+	/* get current speed */
+	prev_speed = speedstep_get_processor_frequency(processor);
+	if (!prev_speed)
+		return EIO;
+	
+	local_irq_save(flags);
+
+	/* switch to low state */
+	set_state(SPEEDSTEP_LOW, 0);
+	*low_speed = speedstep_get_processor_frequency(processor);
+	if (!*low_speed) {
+		ret = EIO;
+		goto out;
+	}
+
+	/* switch to high state */
+	set_state(SPEEDSTEP_HIGH, 0);
+	*high_speed = speedstep_get_processor_frequency(processor);
+	if (!*high_speed) {
+		ret = EIO;
+		goto out;
+	}
+
+	if (*low_speed == *high_speed) {
+		ret = ENODEV;
+		goto out;
+	}
+
+	/* switch to previous state, if necessary */
+	if (*high_speed != prev_speed)
+		set_state(SPEEDSTEP_LOW, 0);
+
+ out:
+	local_irq_restore(flags);
+	return (ret);
+}
+EXPORT_SYMBOL_GPL(speedstep_get_freqs);
+
+MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>");
+MODULE_DESCRIPTION ("Library for Intel SpeedStep 1 or 2 cpufreq drivers.");
+MODULE_LICENSE ("GPL");

arch/i386/kernel/cpu/cpufreq/speedstep-lib.h

+/*
+ * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
+ *
+ *  Licensed under the terms of the GNU GPL License version 2.
+ *
+ *  Library for common functions for Intel SpeedStep v.1 and v.2 support
+ *
+ *  BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*
+ */
+
+
+
+/* processors */
+
+#define SPEEDSTEP_PROCESSOR_PIII_C_EARLY	0x00000001  /* Coppermine core */
+#define SPEEDSTEP_PROCESSOR_PIII_C		0x00000002  /* Coppermine core */
+#define SPEEDSTEP_PROCESSOR_PIII_T 		0x00000003  /* Tualatin core */
+#define SPEEDSTEP_PROCESSOR_P4M			0x00000004  /* P4-M with 100 MHz FSB */
+
+/* speedstep states -- only two of them */
+
+#define SPEEDSTEP_HIGH                  0x00000000
+#define SPEEDSTEP_LOW                   0x00000001
+
+
+/* detect a speedstep-capable processor */
+extern unsigned int speedstep_detect_processor (void);
+
+/* detect the current speed (in khz) of the processor */
+extern unsigned int speedstep_get_processor_frequency(unsigned int processor);
+
+
+/* detect the low and high speeds of the processor. The callback 
+ * set_state"'s first argument is either SPEEDSTEP_HIGH or 
+ * SPEEDSTEP_LOW; the second argument is zero so that no 
+ * cpufreq_notify_transition calls are initiated.
+ */
+extern unsigned int speedstep_get_freqs(unsigned int processor,
+	  unsigned int *low_speed,
+	  unsigned int *high_speed,
+	  void (*set_state) (unsigned int state, unsigned int notify));