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Diffstat (limited to 'arch/i386/kernel/cpu/cpufreq/powernow-k7.c')
-rw-r--r--arch/i386/kernel/cpu/cpufreq/powernow-k7.c690
1 files changed, 690 insertions, 0 deletions
diff --git a/arch/i386/kernel/cpu/cpufreq/powernow-k7.c b/arch/i386/kernel/cpu/cpufreq/powernow-k7.c
new file mode 100644
index 00000000000..913f652623d
--- /dev/null
+++ b/arch/i386/kernel/cpu/cpufreq/powernow-k7.c
@@ -0,0 +1,690 @@
+/*
+ * AMD K7 Powernow driver.
+ * (C) 2003 Dave Jones <davej@codemonkey.org.uk> on behalf of SuSE Labs.
+ * (C) 2003-2004 Dave Jones <davej@redhat.com>
+ *
+ * Licensed under the terms of the GNU GPL License version 2.
+ * Based upon datasheets & sample CPUs kindly provided by AMD.
+ *
+ * Errata 5: Processor may fail to execute a FID/VID change in presence of interrupt.
+ * - We cli/sti on stepping A0 CPUs around the FID/VID transition.
+ * Errata 15: Processors with half frequency multipliers may hang upon wakeup from disconnect.
+ * - We disable half multipliers if ACPI is used on A0 stepping CPUs.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/cpufreq.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/dmi.h>
+
+#include <asm/msr.h>
+#include <asm/timex.h>
+#include <asm/io.h>
+#include <asm/system.h>
+
+#ifdef CONFIG_X86_POWERNOW_K7_ACPI
+#include <linux/acpi.h>
+#include <acpi/processor.h>
+#endif
+
+#include "powernow-k7.h"
+
+#define PFX "powernow: "
+
+
+struct psb_s {
+ u8 signature[10];
+ u8 tableversion;
+ u8 flags;
+ u16 settlingtime;
+ u8 reserved1;
+ u8 numpst;
+};
+
+struct pst_s {
+ u32 cpuid;
+ u8 fsbspeed;
+ u8 maxfid;
+ u8 startvid;
+ u8 numpstates;
+};
+
+#ifdef CONFIG_X86_POWERNOW_K7_ACPI
+union powernow_acpi_control_t {
+ struct {
+ unsigned long fid:5,
+ vid:5,
+ sgtc:20,
+ res1:2;
+ } bits;
+ unsigned long val;
+};
+#endif
+
+#ifdef CONFIG_CPU_FREQ_DEBUG
+/* divide by 1000 to get VCore voltage in V. */
+static int mobile_vid_table[32] = {
+ 2000, 1950, 1900, 1850, 1800, 1750, 1700, 1650,
+ 1600, 1550, 1500, 1450, 1400, 1350, 1300, 0,
+ 1275, 1250, 1225, 1200, 1175, 1150, 1125, 1100,
+ 1075, 1050, 1025, 1000, 975, 950, 925, 0,
+};
+#endif
+
+/* divide by 10 to get FID. */
+static int fid_codes[32] = {
+ 110, 115, 120, 125, 50, 55, 60, 65,
+ 70, 75, 80, 85, 90, 95, 100, 105,
+ 30, 190, 40, 200, 130, 135, 140, 210,
+ 150, 225, 160, 165, 170, 180, -1, -1,
+};
+
+/* This parameter is used in order to force ACPI instead of legacy method for
+ * configuration purpose.
+ */
+
+static int acpi_force;
+
+static struct cpufreq_frequency_table *powernow_table;
+
+static unsigned int can_scale_bus;
+static unsigned int can_scale_vid;
+static unsigned int minimum_speed=-1;
+static unsigned int maximum_speed;
+static unsigned int number_scales;
+static unsigned int fsb;
+static unsigned int latency;
+static char have_a0;
+
+#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "powernow-k7", msg)
+
+static int check_fsb(unsigned int fsbspeed)
+{
+ int delta;
+ unsigned int f = fsb / 1000;
+
+ delta = (fsbspeed > f) ? fsbspeed - f : f - fsbspeed;
+ return (delta < 5);
+}
+
+static int check_powernow(void)
+{
+ struct cpuinfo_x86 *c = cpu_data;
+ unsigned int maxei, eax, ebx, ecx, edx;
+
+ if ((c->x86_vendor != X86_VENDOR_AMD) || (c->x86 !=6)) {
+#ifdef MODULE
+ printk (KERN_INFO PFX "This module only works with AMD K7 CPUs\n");
+#endif
+ return 0;
+ }
+
+ /* Get maximum capabilities */
+ maxei = cpuid_eax (0x80000000);
+ if (maxei < 0x80000007) { /* Any powernow info ? */
+#ifdef MODULE
+ printk (KERN_INFO PFX "No powernow capabilities detected\n");
+#endif
+ return 0;
+ }
+
+ if ((c->x86_model == 6) && (c->x86_mask == 0)) {
+ printk (KERN_INFO PFX "K7 660[A0] core detected, enabling errata workarounds\n");
+ have_a0 = 1;
+ }
+
+ cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
+
+ /* Check we can actually do something before we say anything.*/
+ if (!(edx & (1 << 1 | 1 << 2)))
+ return 0;
+
+ printk (KERN_INFO PFX "PowerNOW! Technology present. Can scale: ");
+
+ if (edx & 1 << 1) {
+ printk ("frequency");
+ can_scale_bus=1;
+ }
+
+ if ((edx & (1 << 1 | 1 << 2)) == 0x6)
+ printk (" and ");
+
+ if (edx & 1 << 2) {
+ printk ("voltage");
+ can_scale_vid=1;
+ }
+
+ printk (".\n");
+ return 1;
+}
+
+
+static int get_ranges (unsigned char *pst)
+{
+ unsigned int j;
+ unsigned int speed;
+ u8 fid, vid;
+
+ powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table) * (number_scales + 1)), GFP_KERNEL);
+ if (!powernow_table)
+ return -ENOMEM;
+ memset(powernow_table, 0, (sizeof(struct cpufreq_frequency_table) * (number_scales + 1)));
+
+ for (j=0 ; j < number_scales; j++) {
+ fid = *pst++;
+
+ powernow_table[j].frequency = (fsb * fid_codes[fid]) / 10;
+ powernow_table[j].index = fid; /* lower 8 bits */
+
+ speed = powernow_table[j].frequency;
+
+ if ((fid_codes[fid] % 10)==5) {
+#ifdef CONFIG_X86_POWERNOW_K7_ACPI
+ if (have_a0 == 1)
+ powernow_table[j].frequency = CPUFREQ_ENTRY_INVALID;
+#endif
+ }
+
+ if (speed < minimum_speed)
+ minimum_speed = speed;
+ if (speed > maximum_speed)
+ maximum_speed = speed;
+
+ vid = *pst++;
+ powernow_table[j].index |= (vid << 8); /* upper 8 bits */
+
+ dprintk (" FID: 0x%x (%d.%dx [%dMHz]) "
+ "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
+ fid_codes[fid] % 10, speed/1000, vid,
+ mobile_vid_table[vid]/1000,
+ mobile_vid_table[vid]%1000);
+ }
+ powernow_table[number_scales].frequency = CPUFREQ_TABLE_END;
+ powernow_table[number_scales].index = 0;
+
+ return 0;
+}
+
+
+static void change_FID(int fid)
+{
+ union msr_fidvidctl fidvidctl;
+
+ rdmsrl (MSR_K7_FID_VID_CTL, fidvidctl.val);
+ if (fidvidctl.bits.FID != fid) {
+ fidvidctl.bits.SGTC = latency;
+ fidvidctl.bits.FID = fid;
+ fidvidctl.bits.VIDC = 0;
+ fidvidctl.bits.FIDC = 1;
+ wrmsrl (MSR_K7_FID_VID_CTL, fidvidctl.val);
+ }
+}
+
+
+static void change_VID(int vid)
+{
+ union msr_fidvidctl fidvidctl;
+
+ rdmsrl (MSR_K7_FID_VID_CTL, fidvidctl.val);
+ if (fidvidctl.bits.VID != vid) {
+ fidvidctl.bits.SGTC = latency;
+ fidvidctl.bits.VID = vid;
+ fidvidctl.bits.FIDC = 0;
+ fidvidctl.bits.VIDC = 1;
+ wrmsrl (MSR_K7_FID_VID_CTL, fidvidctl.val);
+ }
+}
+
+
+static void change_speed (unsigned int index)
+{
+ u8 fid, vid;
+ struct cpufreq_freqs freqs;
+ union msr_fidvidstatus fidvidstatus;
+ int cfid;
+
+ /* fid are the lower 8 bits of the index we stored into
+ * the cpufreq frequency table in powernow_decode_bios,
+ * vid are the upper 8 bits.
+ */
+
+ fid = powernow_table[index].index & 0xFF;
+ vid = (powernow_table[index].index & 0xFF00) >> 8;
+
+ freqs.cpu = 0;
+
+ rdmsrl (MSR_K7_FID_VID_STATUS, fidvidstatus.val);
+ cfid = fidvidstatus.bits.CFID;
+ freqs.old = fsb * fid_codes[cfid] / 10;
+
+ freqs.new = powernow_table[index].frequency;
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+ /* Now do the magic poking into the MSRs. */
+
+ if (have_a0 == 1) /* A0 errata 5 */
+ local_irq_disable();
+
+ if (freqs.old > freqs.new) {
+ /* Going down, so change FID first */
+ change_FID(fid);
+ change_VID(vid);
+ } else {
+ /* Going up, so change VID first */
+ change_VID(vid);
+ change_FID(fid);
+ }
+
+
+ if (have_a0 == 1)
+ local_irq_enable();
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+}
+
+
+#ifdef CONFIG_X86_POWERNOW_K7_ACPI
+
+static struct acpi_processor_performance *acpi_processor_perf;
+
+static int powernow_acpi_init(void)
+{
+ int i;
+ int retval = 0;
+ union powernow_acpi_control_t pc;
+
+ if (acpi_processor_perf != NULL && powernow_table != NULL) {
+ retval = -EINVAL;
+ goto err0;
+ }
+
+ acpi_processor_perf = kmalloc(sizeof(struct acpi_processor_performance),
+ GFP_KERNEL);
+
+ if (!acpi_processor_perf) {
+ retval = -ENOMEM;
+ goto err0;
+ }
+
+ memset(acpi_processor_perf, 0, sizeof(struct acpi_processor_performance));
+
+ if (acpi_processor_register_performance(acpi_processor_perf, 0)) {
+ retval = -EIO;
+ goto err1;
+ }
+
+ if (acpi_processor_perf->control_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) {
+ retval = -ENODEV;
+ goto err2;
+ }
+
+ if (acpi_processor_perf->status_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) {
+ retval = -ENODEV;
+ goto err2;
+ }
+
+ number_scales = acpi_processor_perf->state_count;
+
+ if (number_scales < 2) {
+ retval = -ENODEV;
+ goto err2;
+ }
+
+ powernow_table = kmalloc((number_scales + 1) * (sizeof(struct cpufreq_frequency_table)), GFP_KERNEL);
+ if (!powernow_table) {
+ retval = -ENOMEM;
+ goto err2;
+ }
+
+ memset(powernow_table, 0, ((number_scales + 1) * sizeof(struct cpufreq_frequency_table)));
+
+ pc.val = (unsigned long) acpi_processor_perf->states[0].control;
+ for (i = 0; i < number_scales; i++) {
+ u8 fid, vid;
+ unsigned int speed;
+
+ pc.val = (unsigned long) acpi_processor_perf->states[i].control;
+ dprintk ("acpi: P%d: %d MHz %d mW %d uS control %08x SGTC %d\n",
+ i,
+ (u32) acpi_processor_perf->states[i].core_frequency,
+ (u32) acpi_processor_perf->states[i].power,
+ (u32) acpi_processor_perf->states[i].transition_latency,
+ (u32) acpi_processor_perf->states[i].control,
+ pc.bits.sgtc);
+
+ vid = pc.bits.vid;
+ fid = pc.bits.fid;
+
+ powernow_table[i].frequency = fsb * fid_codes[fid] / 10;
+ powernow_table[i].index = fid; /* lower 8 bits */
+ powernow_table[i].index |= (vid << 8); /* upper 8 bits */
+
+ speed = powernow_table[i].frequency;
+
+ if ((fid_codes[fid] % 10)==5) {
+ if (have_a0 == 1)
+ powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
+ }
+
+ dprintk (" FID: 0x%x (%d.%dx [%dMHz]) "
+ "VID: 0x%x (%d.%03dV)\n", fid, fid_codes[fid] / 10,
+ fid_codes[fid] % 10, speed/1000, vid,
+ mobile_vid_table[vid]/1000,
+ mobile_vid_table[vid]%1000);
+
+ if (latency < pc.bits.sgtc)
+ latency = pc.bits.sgtc;
+
+ if (speed < minimum_speed)
+ minimum_speed = speed;
+ if (speed > maximum_speed)
+ maximum_speed = speed;
+ }
+
+ powernow_table[i].frequency = CPUFREQ_TABLE_END;
+ powernow_table[i].index = 0;
+
+ /* notify BIOS that we exist */
+ acpi_processor_notify_smm(THIS_MODULE);
+
+ return 0;
+
+err2:
+ acpi_processor_unregister_performance(acpi_processor_perf, 0);
+err1:
+ kfree(acpi_processor_perf);
+err0:
+ printk(KERN_WARNING PFX "ACPI perflib can not be used in this platform\n");
+ acpi_processor_perf = NULL;
+ return retval;
+}
+#else
+static int powernow_acpi_init(void)
+{
+ printk(KERN_INFO PFX "no support for ACPI processor found."
+ " Please recompile your kernel with ACPI processor\n");
+ return -EINVAL;
+}
+#endif
+
+static int powernow_decode_bios (int maxfid, int startvid)
+{
+ struct psb_s *psb;
+ struct pst_s *pst;
+ unsigned int i, j;
+ unsigned char *p;
+ unsigned int etuple;
+ unsigned int ret;
+
+ etuple = cpuid_eax(0x80000001);
+
+ for (i=0xC0000; i < 0xffff0 ; i+=16) {
+
+ p = phys_to_virt(i);
+
+ if (memcmp(p, "AMDK7PNOW!", 10) == 0){
+ dprintk ("Found PSB header at %p\n", p);
+ psb = (struct psb_s *) p;
+ dprintk ("Table version: 0x%x\n", psb->tableversion);
+ if (psb->tableversion != 0x12) {
+ printk (KERN_INFO PFX "Sorry, only v1.2 tables supported right now\n");
+ return -ENODEV;
+ }
+
+ dprintk ("Flags: 0x%x\n", psb->flags);
+ if ((psb->flags & 1)==0) {
+ dprintk ("Mobile voltage regulator\n");
+ } else {
+ dprintk ("Desktop voltage regulator\n");
+ }
+
+ latency = psb->settlingtime;
+ if (latency < 100) {
+ printk (KERN_INFO PFX "BIOS set settling time to %d microseconds."
+ "Should be at least 100. Correcting.\n", latency);
+ latency = 100;
+ }
+ dprintk ("Settling Time: %d microseconds.\n", psb->settlingtime);
+ dprintk ("Has %d PST tables. (Only dumping ones relevant to this CPU).\n", psb->numpst);
+
+ p += sizeof (struct psb_s);
+
+ pst = (struct pst_s *) p;
+
+ for (i = 0 ; i <psb->numpst; i++) {
+ pst = (struct pst_s *) p;
+ number_scales = pst->numpstates;
+
+ if ((etuple == pst->cpuid) && check_fsb(pst->fsbspeed) &&
+ (maxfid==pst->maxfid) && (startvid==pst->startvid))
+ {
+ dprintk ("PST:%d (@%p)\n", i, pst);
+ dprintk (" cpuid: 0x%x fsb: %d maxFID: 0x%x startvid: 0x%x\n",
+ pst->cpuid, pst->fsbspeed, pst->maxfid, pst->startvid);
+
+ ret = get_ranges ((char *) pst + sizeof (struct pst_s));
+ return ret;
+
+ } else {
+ p = (char *) pst + sizeof (struct pst_s);
+ for (j=0 ; j < number_scales; j++)
+ p+=2;
+ }
+ }
+ printk (KERN_INFO PFX "No PST tables match this cpuid (0x%x)\n", etuple);
+ printk (KERN_INFO PFX "This is indicative of a broken BIOS.\n");
+
+ return -EINVAL;
+ }
+ p++;
+ }
+
+ return -ENODEV;
+}
+
+
+static int powernow_target (struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ unsigned int newstate;
+
+ if (cpufreq_frequency_table_target(policy, powernow_table, target_freq, relation, &newstate))
+ return -EINVAL;
+
+ change_speed(newstate);
+
+ return 0;
+}
+
+
+static int powernow_verify (struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy, powernow_table);
+}
+
+/*
+ * We use the fact that the bus frequency is somehow
+ * a multiple of 100000/3 khz, then we compute sgtc according
+ * to this multiple.
+ * That way, we match more how AMD thinks all of that work.
+ * We will then get the same kind of behaviour already tested under
+ * the "well-known" other OS.
+ */
+static int __init fixup_sgtc(void)
+{
+ unsigned int sgtc;
+ unsigned int m;
+
+ m = fsb / 3333;
+ if ((m % 10) >= 5)
+ m += 5;
+
+ m /= 10;
+
+ sgtc = 100 * m * latency;
+ sgtc = sgtc / 3;
+ if (sgtc > 0xfffff) {
+ printk(KERN_WARNING PFX "SGTC too large %d\n", sgtc);
+ sgtc = 0xfffff;
+ }
+ return sgtc;
+}
+
+static unsigned int powernow_get(unsigned int cpu)
+{
+ union msr_fidvidstatus fidvidstatus;
+ unsigned int cfid;
+
+ if (cpu)
+ return 0;
+ rdmsrl (MSR_K7_FID_VID_STATUS, fidvidstatus.val);
+ cfid = fidvidstatus.bits.CFID;
+
+ return (fsb * fid_codes[cfid] / 10);
+}
+
+
+static int __init acer_cpufreq_pst(struct dmi_system_id *d)
+{
+ printk(KERN_WARNING "%s laptop with broken PST tables in BIOS detected.\n", d->ident);
+ printk(KERN_WARNING "You need to downgrade to 3A21 (09/09/2002), or try a newer BIOS than 3A71 (01/20/2003)\n");
+ printk(KERN_WARNING "cpufreq scaling has been disabled as a result of this.\n");
+ return 0;
+}
+
+/*
+ * Some Athlon laptops have really fucked PST tables.
+ * A BIOS update is all that can save them.
+ * Mention this, and disable cpufreq.
+ */
+static struct dmi_system_id __initdata powernow_dmi_table[] = {
+ {
+ .callback = acer_cpufreq_pst,
+ .ident = "Acer Aspire",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Insyde Software"),
+ DMI_MATCH(DMI_BIOS_VERSION, "3A71"),
+ },
+ },
+ { }
+};
+
+static int __init powernow_cpu_init (struct cpufreq_policy *policy)
+{
+ union msr_fidvidstatus fidvidstatus;
+ int result;
+
+ if (policy->cpu != 0)
+ return -ENODEV;
+
+ rdmsrl (MSR_K7_FID_VID_STATUS, fidvidstatus.val);
+
+ /* A K7 with powernow technology is set to max frequency by BIOS */
+ fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.MFID];
+ if (!fsb) {
+ printk(KERN_WARNING PFX "can not determine bus frequency\n");
+ return -EINVAL;
+ }
+ dprintk("FSB: %3d.%03d MHz\n", fsb/1000, fsb%1000);
+
+ if (dmi_check_system(powernow_dmi_table) || acpi_force) {
+ printk (KERN_INFO PFX "PSB/PST known to be broken. Trying ACPI instead\n");
+ result = powernow_acpi_init();
+ } else {
+ result = powernow_decode_bios(fidvidstatus.bits.MFID, fidvidstatus.bits.SVID);
+ if (result) {
+ printk (KERN_INFO PFX "Trying ACPI perflib\n");
+ maximum_speed = 0;
+ minimum_speed = -1;
+ latency = 0;
+ result = powernow_acpi_init();
+ if (result) {
+ printk (KERN_INFO PFX "ACPI and legacy methods failed\n");
+ printk (KERN_INFO PFX "See http://www.codemonkey.org.uk/projects/cpufreq/powernow-k7.shtml\n");
+ }
+ } else {
+ /* SGTC use the bus clock as timer */
+ latency = fixup_sgtc();
+ printk(KERN_INFO PFX "SGTC: %d\n", latency);
+ }
+ }
+
+ if (result)
+ return result;
+
+ printk (KERN_INFO PFX "Minimum speed %d MHz. Maximum speed %d MHz.\n",
+ minimum_speed/1000, maximum_speed/1000);
+
+ policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
+
+ policy->cpuinfo.transition_latency = cpufreq_scale(2000000UL, fsb, latency);
+
+ policy->cur = powernow_get(0);
+
+ cpufreq_frequency_table_get_attr(powernow_table, policy->cpu);
+
+ return cpufreq_frequency_table_cpuinfo(policy, powernow_table);
+}
+
+static int powernow_cpu_exit (struct cpufreq_policy *policy) {
+ cpufreq_frequency_table_put_attr(policy->cpu);
+
+#ifdef CONFIG_X86_POWERNOW_K7_ACPI
+ if (acpi_processor_perf) {
+ acpi_processor_unregister_performance(acpi_processor_perf, 0);
+ kfree(acpi_processor_perf);
+ }
+#endif
+
+ if (powernow_table)
+ kfree(powernow_table);
+
+ return 0;
+}
+
+static struct freq_attr* powernow_table_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static struct cpufreq_driver powernow_driver = {
+ .verify = powernow_verify,
+ .target = powernow_target,
+ .get = powernow_get,
+ .init = powernow_cpu_init,
+ .exit = powernow_cpu_exit,
+ .name = "powernow-k7",
+ .owner = THIS_MODULE,
+ .attr = powernow_table_attr,
+};
+
+static int __init powernow_init (void)
+{
+ if (check_powernow()==0)
+ return -ENODEV;
+ return cpufreq_register_driver(&powernow_driver);
+}
+
+
+static void __exit powernow_exit (void)
+{
+ cpufreq_unregister_driver(&powernow_driver);
+}
+
+module_param(acpi_force, int, 0444);
+MODULE_PARM_DESC(acpi_force, "Force ACPI to be used.");
+
+MODULE_AUTHOR ("Dave Jones <davej@codemonkey.org.uk>");
+MODULE_DESCRIPTION ("Powernow driver for AMD K7 processors.");
+MODULE_LICENSE ("GPL");
+
+late_initcall(powernow_init);
+module_exit(powernow_exit);
+
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-27 22:42:08 +0000