--- /dev/null
+/*
+ * (C) 2001-2004 Dave Jones.
+ * (C) 2002 Padraig Brady. <padraig@antefacto.com>
+ *
+ * Licensed under the terms of the GNU GPL License version 2.
+ * Based upon datasheets & sample CPUs kindly provided by VIA.
+ *
+ * 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 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 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
+ * too well in practice so we don't even try to use this.
+ *
+ * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/cpufreq.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/timex.h>
+#include <linux/io.h>
+#include <linux/acpi.h>
+
+#include <asm/msr.h>
+#include <asm/cpu_device_id.h>
+#include <acpi/processor.h>
+
+#include "longhaul.h"
+
+#define PFX "longhaul: "
+
+#define TYPE_LONGHAUL_V1 1
+#define TYPE_LONGHAUL_V2 2
+#define TYPE_POWERSAVER 3
+
+#define CPU_SAMUEL 1
+#define CPU_SAMUEL2 2
+#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)
+
+static int cpu_model;
+static unsigned int numscales = 16;
+static unsigned int fsb;
+
+static const struct mV_pos *vrm_mV_table;
+static const unsigned char *mV_vrm_table;
+
+static unsigned int highest_speed, lowest_speed; /* kHz */
+static unsigned int minmult, maxmult;
+static int can_scale_voltage;
+static struct acpi_processor *pr;
+static struct acpi_processor_cx *cx;
+static u32 acpi_regs_addr;
+static u8 longhaul_flags;
+static unsigned int longhaul_index;
+
+/* Module parameters */
+static int scale_voltage;
+static int disable_acpi_c3;
+static int revid_errata;
+static int enable;
+
+/* Clock ratios multiplied by 10 */
+static int mults[32];
+static int eblcr[32];
+static int longhaul_version;
+static struct cpufreq_frequency_table *longhaul_table;
+
+static char speedbuffer[8];
+
+static char *print_speed(int speed)
+{
+ if (speed < 1000) {
+ snprintf(speedbuffer, sizeof(speedbuffer), "%dMHz", speed);
+ return speedbuffer;
+ }
+
+ if (speed%1000 == 0)
+ snprintf(speedbuffer, sizeof(speedbuffer),
+ "%dGHz", speed/1000);
+ else
+ snprintf(speedbuffer, sizeof(speedbuffer),
+ "%d.%dGHz", speed/1000, (speed%1000)/100);
+
+ return speedbuffer;
+}
+
+
+static unsigned int calc_speed(int mult)
+{
+ int khz;
+ khz = (mult/10)*fsb;
+ if (mult%10)
+ khz += fsb/2;
+ khz *= 1000;
+ return khz;
+}
+
+
+static int longhaul_get_cpu_mult(void)
+{
+ unsigned long invalue = 0, lo, hi;
+
+ rdmsr(MSR_IA32_EBL_CR_POWERON, lo, hi);
+ invalue = (lo & (1<<22|1<<23|1<<24|1<<25))>>22;
+ if (longhaul_version == TYPE_LONGHAUL_V2 ||
+ longhaul_version == TYPE_POWERSAVER) {
+ if (lo & (1<<27))
+ invalue += 16;
+ }
+ return eblcr[invalue];
+}
+
+/* For processor with BCR2 MSR */
+
+static void do_longhaul1(unsigned int mults_index)
+{
+ union msr_bcr2 bcr2;
+
+ rdmsrl(MSR_VIA_BCR2, bcr2.val);
+ /* Enable software clock multiplier */
+ bcr2.bits.ESOFTBF = 1;
+ bcr2.bits.CLOCKMUL = mults_index & 0xff;
+
+ /* Sync to timer tick */
+ safe_halt();
+ /* Change frequency on next halt or sleep */
+ wrmsrl(MSR_VIA_BCR2, bcr2.val);
+ /* Invoke transition */
+ ACPI_FLUSH_CPU_CACHE();
+ halt();
+
+ /* Disable software clock multiplier */
+ local_irq_disable();
+ rdmsrl(MSR_VIA_BCR2, bcr2.val);
+ bcr2.bits.ESOFTBF = 0;
+ wrmsrl(MSR_VIA_BCR2, bcr2.val);
+}
+
+/* For processor with Longhaul MSR */
+
+static void do_powersaver(int cx_address, unsigned int mults_index,
+ unsigned int dir)
+{
+ union msr_longhaul longhaul;
+ u32 t;
+
+ rdmsrl(MSR_VIA_LONGHAUL, longhaul.val);
+ /* Setup new frequency */
+ if (!revid_errata)
+ longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
+ else
+ longhaul.bits.RevisionKey = 0;
+ longhaul.bits.SoftBusRatio = mults_index & 0xf;
+ longhaul.bits.SoftBusRatio4 = (mults_index & 0x10) >> 4;
+ /* Setup new voltage */
+ if (can_scale_voltage)
+ longhaul.bits.SoftVID = (mults_index >> 8) & 0x1f;
+ /* Sync to timer tick */
+ safe_halt();
+ /* Raise voltage if necessary */
+ if (can_scale_voltage && dir) {
+ 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);
+ }
+
+ /* Change frequency on next halt or sleep */
+ longhaul.bits.EnableSoftBusRatio = 1;
+ wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
+ 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);
+ }
+ /* Disable bus ratio bit */
+ longhaul.bits.EnableSoftBusRatio = 0;
+ wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
+
+ /* Reduce voltage if necessary */
+ if (can_scale_voltage && !dir) {
+ 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_set_cpu_frequency()
+ * @mults_index : bitpattern of the new multiplier.
+ *
+ * Sets a new clock ratio.
+ */
+
+static int longhaul_setstate(struct cpufreq_policy *policy,
+ unsigned int table_index)
+{
+ unsigned int mults_index;
+ int speed, mult;
+ struct cpufreq_freqs freqs;
+ unsigned long flags;
+ unsigned int pic1_mask, pic2_mask;
+ u16 bm_status = 0;
+ u32 bm_timeout = 1000;
+ unsigned int dir = 0;
+
+ mults_index = longhaul_table[table_index].driver_data;
+ /* Safety precautions */
+ mult = mults[mults_index & 0x1f];
+ if (mult == -1)
+ return -EINVAL;
+
+ speed = calc_speed(mult);
+ if ((speed > highest_speed) || (speed < lowest_speed))
+ return -EINVAL;
+
+ /* Voltage transition before frequency transition? */
+ if (can_scale_voltage && longhaul_index < table_index)
+ dir = 1;
+
+ freqs.old = calc_speed(longhaul_get_cpu_mult());
+ freqs.new = speed;
+
+ pr_debug("Setting to FSB:%dMHz Mult:%d.%dx (%s)\n",
+ fsb, mult/10, mult%10, print_speed(speed/1000));
+retry_loop:
+ preempt_disable();
+ local_irq_save(flags);
+
+ pic2_mask = inb(0xA1);
+ pic1_mask = inb(0x21); /* works on C3. save mask. */
+ outb(0xFF, 0xA1); /* Overkill */
+ outb(0xFE, 0x21); /* TMR0 only */
+
+ /* Wait while PCI bus is busy. */
+ if (acpi_regs_addr && (longhaul_flags & USE_NORTHBRIDGE
+ || ((pr != NULL) && pr->flags.bm_control))) {
+ bm_status = inw(acpi_regs_addr);
+ bm_status &= 1 << 4;
+ while (bm_status && bm_timeout) {
+ outw(1 << 4, acpi_regs_addr);
+ bm_timeout--;
+ bm_status = inw(acpi_regs_addr);
+ bm_status &= 1 << 4;
+ }
+ }
+
+ if (longhaul_flags & USE_NORTHBRIDGE) {
+ /* Disable AGP and PCI arbiters */
+ outb(3, 0x22);
+ } else if ((pr != NULL) && pr->flags.bm_control) {
+ /* Disable bus master arbitration */
+ acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1);
+ }
+ switch (longhaul_version) {
+
+ /*
+ * Longhaul v1. (Samuel[C5A] and Samuel2 stepping 0[C5B])
+ * Software controlled multipliers only.
+ */
+ case TYPE_LONGHAUL_V1:
+ do_longhaul1(mults_index);
+ break;
+
+ /*
+ * Longhaul v2 appears in Samuel2 Steppings 1->7 [C5B] and Ezra [C5C]
+ *
+ * Longhaul v3 (aka Powersaver). (Ezra-T [C5M] & Nehemiah [C5N])
+ * 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 */
+ acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 0);
+ do_powersaver(cx->address, mults_index, dir);
+ } else {
+ do_powersaver(0, mults_index, dir);
+ }
+ break;
+ }
+
+ if (longhaul_flags & USE_NORTHBRIDGE) {
+ /* Enable arbiters */
+ outb(0, 0x22);
+ } else if ((pr != NULL) && pr->flags.bm_control) {
+ /* Enable bus master arbitration */
+ acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0);
+ }
+ outb(pic2_mask, 0xA1); /* restore mask */
+ outb(pic1_mask, 0x21);
+
+ local_irq_restore(flags);
+ preempt_enable();
+
+ freqs.new = calc_speed(longhaul_get_cpu_mult());
+ /* Check if requested frequency is set. */
+ if (unlikely(freqs.new != speed)) {
+ printk(KERN_INFO PFX "Failed to set requested frequency!\n");
+ /* Revision ID = 1 but processor is expecting revision key
+ * equal to 0. Jumpers at the bottom of processor will change
+ * multiplier and FSB, but will not change bits in Longhaul
+ * MSR nor enable voltage scaling. */
+ if (!revid_errata) {
+ printk(KERN_INFO PFX "Enabling \"Ignore Revision ID\" "
+ "option.\n");
+ revid_errata = 1;
+ msleep(200);
+ goto retry_loop;
+ }
+ /* Why ACPI C3 sometimes doesn't work is a mystery for me.
+ * But it does happen. Processor is entering ACPI C3 state,
+ * but it doesn't change frequency. I tried poking various
+ * bits in northbridge registers, but without success. */
+ if (longhaul_flags & USE_ACPI_C3) {
+ printk(KERN_INFO PFX "Disabling ACPI C3 support.\n");
+ longhaul_flags &= ~USE_ACPI_C3;
+ if (revid_errata) {
+ printk(KERN_INFO PFX "Disabling \"Ignore "
+ "Revision ID\" option.\n");
+ revid_errata = 0;
+ }
+ msleep(200);
+ goto retry_loop;
+ }
+ /* This shouldn't happen. Longhaul ver. 2 was reported not
+ * working on processors without voltage scaling, but with
+ * RevID = 1. RevID errata will make things right. Just
+ * to be 100% sure. */
+ if (longhaul_version == TYPE_LONGHAUL_V2) {
+ printk(KERN_INFO PFX "Switching to Longhaul ver. 1\n");
+ longhaul_version = TYPE_LONGHAUL_V1;
+ msleep(200);
+ goto retry_loop;
+ }
+ }
+
+ if (!bm_timeout) {
+ printk(KERN_INFO PFX "Warning: Timeout while waiting for "
+ "idle PCI bus.\n");
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+/*
+ * Centaur decided to make life a little more tricky.
+ * Only longhaul v1 is allowed to read EBLCR BSEL[0:1].
+ * Samuel2 and above have to try and guess what the FSB is.
+ * We do this by assuming we booted at maximum multiplier, and interpolate
+ * between that value multiplied by possible FSBs and cpu_mhz which
+ * was calculated at boot time. Really ugly, but no other way to do this.
+ */
+
+#define ROUNDING 0xf
+
+static int guess_fsb(int mult)
+{
+ int speed = cpu_khz / 1000;
+ int i;
+ int speeds[] = { 666, 1000, 1333, 2000 };
+ int f_max, f_min;
+
+ 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;
+}
+
+
+static int longhaul_get_ranges(void)
+{
+ unsigned int i, j, k = 0;
+ unsigned int ratio;
+ int mult;
+
+ /* 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 useful 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;
+ }
+
+ pr_debug("MinMult:%d.%dx MaxMult:%d.%dx\n",
+ minmult/10, minmult%10, maxmult/10, maxmult%10);
+
+ highest_speed = calc_speed(maxmult);
+ lowest_speed = calc_speed(minmult);
+ pr_debug("FSB:%dMHz Lowest speed: %s Highest speed:%s\n", fsb,
+ print_speed(lowest_speed/1000),
+ print_speed(highest_speed/1000));
+
+ if (lowest_speed == highest_speed) {
+ printk(KERN_INFO PFX "highestspeed == lowest, aborting.\n");
+ return -EINVAL;
+ }
+ if (lowest_speed > highest_speed) {
+ printk(KERN_INFO PFX "nonsense! lowest (%d > %d) !\n",
+ lowest_speed, highest_speed);
+ return -EINVAL;
+ }
+
+ longhaul_table = kzalloc((numscales + 1) * sizeof(*longhaul_table),
+ GFP_KERNEL);
+ if (!longhaul_table)
+ return -ENOMEM;
+
+ for (j = 0; j < numscales; j++) {
+ ratio = mults[j];
+ if (ratio == -1)
+ continue;
+ if (ratio > maxmult || ratio < minmult)
+ continue;
+ longhaul_table[k].frequency = calc_speed(ratio);
+ longhaul_table[k].driver_data = j;
+ k++;
+ }
+ if (k <= 1) {
+ kfree(longhaul_table);
+ return -ENODEV;
+ }
+ /* Sort */
+ for (j = 0; j < k - 1; j++) {
+ unsigned int min_f, min_i;
+ min_f = longhaul_table[j].frequency;
+ min_i = j;
+ for (i = j + 1; i < k; i++) {
+ if (longhaul_table[i].frequency < min_f) {
+ min_f = longhaul_table[i].frequency;
+ min_i = i;
+ }
+ }
+ if (min_i != j) {
+ swap(longhaul_table[j].frequency,
+ longhaul_table[min_i].frequency);
+ swap(longhaul_table[j].driver_data,
+ longhaul_table[min_i].driver_data);
+ }
+ }
+
+ longhaul_table[k].frequency = CPUFREQ_TABLE_END;
+
+ /* Find index we are running on */
+ for (j = 0; j < k; j++) {
+ if (mults[longhaul_table[j].driver_data & 0x1f] == mult) {
+ longhaul_index = j;
+ break;
+ }
+ }
+ return 0;
+}
+
+
+static void longhaul_setup_voltagescaling(void)
+{
+ struct cpufreq_frequency_table *freq_pos;
+ union msr_longhaul longhaul;
+ struct mV_pos minvid, maxvid, vid;
+ unsigned int j, speed, pos, kHz_step, numvscales;
+ int min_vid_speed;
+
+ rdmsrl(MSR_VIA_LONGHAUL, longhaul.val);
+ if (!(longhaul.bits.RevisionID & 1)) {
+ printk(KERN_INFO PFX "Voltage scaling not supported by CPU.\n");
+ return;
+ }
+
+ if (!longhaul.bits.VRMRev) {
+ printk(KERN_INFO PFX "VRM 8.5\n");
+ vrm_mV_table = &vrm85_mV[0];
+ 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];
+
+ if (minvid.mV == 0 || maxvid.mV == 0 || minvid.mV > maxvid.mV) {
+ printk(KERN_INFO PFX "Bogus values Min:%d.%03d Max:%d.%03d. "
+ "Voltage scaling disabled.\n",
+ minvid.mV/1000, minvid.mV%1000,
+ maxvid.mV/1000, maxvid.mV%1000);
+ return;
+ }
+
+ if (minvid.mV == maxvid.mV) {
+ printk(KERN_INFO PFX "Claims to support voltage scaling but "
+ "min & max are both %d.%03d. "
+ "Voltage scaling disabled\n",
+ maxvid.mV/1000, maxvid.mV%1000);
+ return;
+ }
+
+ /* 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[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;
+
+ cpufreq_for_each_entry(freq_pos, longhaul_table) {
+ speed = freq_pos->frequency;
+ if (speed > min_vid_speed)
+ pos = (speed - min_vid_speed) / kHz_step + minvid.pos;
+ else
+ pos = minvid.pos;
+ freq_pos->driver_data |= mV_vrm_table[pos] << 8;
+ vid = vrm_mV_table[mV_vrm_table[pos]];
+ printk(KERN_INFO PFX "f: %d kHz, index: %d, vid: %d mV\n",
+ speed, (int)(freq_pos - longhaul_table), vid.mV);
+ }
+
+ can_scale_voltage = 1;
+ printk(KERN_INFO PFX "Voltage scaling enabled.\n");
+}
+
+
+static int longhaul_target(struct cpufreq_policy *policy,
+ unsigned int table_index)
+{
+ unsigned int i;
+ unsigned int dir = 0;
+ u8 vid, current_vid;
+ int retval = 0;
+
+ if (!can_scale_voltage)
+ retval = longhaul_setstate(policy, table_index);
+ else {
+ /* On test system voltage transitions exceeding single
+ * step up or down were turning motherboard off. Both
+ * "ondemand" and "userspace" are unsafe. C7 is doing
+ * this in hardware, C3 is old and we need to do this
+ * in software. */
+ i = longhaul_index;
+ current_vid = (longhaul_table[longhaul_index].driver_data >> 8);
+ current_vid &= 0x1f;
+ if (table_index > longhaul_index)
+ dir = 1;
+ while (i != table_index) {
+ vid = (longhaul_table[i].driver_data >> 8) & 0x1f;
+ if (vid != current_vid) {
+ retval = longhaul_setstate(policy, i);
+ current_vid = vid;
+ msleep(200);
+ }
+ if (dir)
+ i++;
+ else
+ i--;
+ }
+ retval = longhaul_setstate(policy, table_index);
+ }
+
+ longhaul_index = table_index;
+ return retval;
+}
+
+
+static unsigned int longhaul_get(unsigned int cpu)
+{
+ if (cpu)
+ return 0;
+ return calc_speed(longhaul_get_cpu_mult());
+}
+
+static acpi_status longhaul_walk_callback(acpi_handle obj_handle,
+ u32 nesting_level,
+ void *context, void **return_value)
+{
+ struct acpi_device *d;
+
+ if (acpi_bus_get_device(obj_handle, &d))
+ return 0;
+
+ *return_value = acpi_driver_data(d);
+ return 1;
+}
+
+/* VIA don't support PM2 reg, but have something similar */
+static int enable_arbiter_disable(void)
+{
+ struct pci_dev *dev;
+ int status = 1;
+ int reg;
+ u8 pci_cmd;
+
+ /* Find PLE133 host bridge */
+ reg = 0x78;
+ dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8601_0,
+ NULL);
+ /* Find PM133/VT8605 host bridge */
+ if (dev == NULL)
+ dev = pci_get_device(PCI_VENDOR_ID_VIA,
+ PCI_DEVICE_ID_VIA_8605_0, NULL);
+ /* Find CLE266 host bridge */
+ if (dev == NULL) {
+ reg = 0x76;
+ dev = pci_get_device(PCI_VENDOR_ID_VIA,
+ PCI_DEVICE_ID_VIA_862X_0, NULL);
+ /* Find CN400 V-Link host bridge */
+ if (dev == NULL)
+ dev = pci_get_device(PCI_VENDOR_ID_VIA, 0x7259, NULL);
+ }
+ if (dev != NULL) {
+ /* Enable access to port 0x22 */
+ pci_read_config_byte(dev, reg, &pci_cmd);
+ 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");
+ status = 0;
+ }
+ }
+ pci_dev_put(dev);
+ return status;
+ }
+ return 0;
+}
+
+static int longhaul_setup_southbridge(void)
+{
+ struct pci_dev *dev;
+ u8 pci_cmd;
+
+ /* Find VT8235 southbridge */
+ dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235, NULL);
+ if (dev == NULL)
+ /* Find VT8237 southbridge */
+ dev = pci_get_device(PCI_VENDOR_ID_VIA,
+ PCI_DEVICE_ID_VIA_8237, 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);
+ /* Get address of ACPI registers block*/
+ pci_read_config_byte(dev, 0x81, &pci_cmd);
+ if (pci_cmd & 1 << 7) {
+ pci_read_config_dword(dev, 0x88, &acpi_regs_addr);
+ acpi_regs_addr &= 0xff00;
+ printk(KERN_INFO PFX "ACPI I/O at 0x%x\n",
+ acpi_regs_addr);
+ }
+
+ pci_dev_put(dev);
+ return 1;
+ }
+ return 0;
+}
+
+static int longhaul_cpu_init(struct cpufreq_policy *policy)
+{
+ struct cpuinfo_x86 *c = &cpu_data(0);
+ char *cpuname = NULL;
+ int ret;
+ u32 lo, hi;
+
+ /* Check what we have on this motherboard */
+ switch (c->x86_model) {
+ case 6:
+ cpu_model = CPU_SAMUEL;
+ cpuname = "C3 'Samuel' [C5A]";
+ longhaul_version = TYPE_LONGHAUL_V1;
+ memcpy(mults, samuel1_mults, sizeof(samuel1_mults));
+ memcpy(eblcr, samuel1_eblcr, sizeof(samuel1_eblcr));
+ break;
+
+ case 7:
+ 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(mults, samuel1_mults, sizeof(samuel1_mults));
+ memcpy(eblcr, 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]";
+ } else {
+ cpu_model = CPU_EZRA;
+ cpuname = "C3 'Ezra' [C5C]";
+ }
+ memcpy(mults, ezra_mults, sizeof(ezra_mults));
+ memcpy(eblcr, ezra_eblcr, sizeof(ezra_eblcr));
+ break;
+ }
+ break;
+
+ case 8:
+ cpu_model = CPU_EZRA_T;
+ cpuname = "C3 'Ezra-T' [C5M]";
+ longhaul_version = TYPE_POWERSAVER;
+ numscales = 32;
+ memcpy(mults, ezrat_mults, sizeof(ezrat_mults));
+ memcpy(eblcr, ezrat_eblcr, sizeof(ezrat_eblcr));
+ break;
+
+ case 9:
+ longhaul_version = TYPE_POWERSAVER;
+ numscales = 32;
+ memcpy(mults, nehemiah_mults, sizeof(nehemiah_mults));
+ memcpy(eblcr, nehemiah_eblcr, sizeof(nehemiah_eblcr));
+ switch (c->x86_mask) {
+ case 0 ... 1:
+ cpu_model = CPU_NEHEMIAH;
+ cpuname = "C3 'Nehemiah A' [C5XLOE]";
+ break;
+ case 2 ... 4:
+ cpu_model = CPU_NEHEMIAH;
+ cpuname = "C3 'Nehemiah B' [C5XLOH]";
+ break;
+ case 5 ... 15:
+ cpu_model = CPU_NEHEMIAH_C;
+ cpuname = "C3 'Nehemiah C' [C5P]";
+ break;
+ }
+ break;
+
+ default:
+ 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) {
+ case TYPE_LONGHAUL_V1:
+ case TYPE_LONGHAUL_V2:
+ printk(KERN_CONT "Longhaul v%d supported.\n", longhaul_version);
+ break;
+ case TYPE_POWERSAVER:
+ printk(KERN_CONT "Powersaver supported.\n");
+ break;
+ };
+
+ /* Doesn't hurt */
+ longhaul_setup_southbridge();
+
+ /* Find ACPI data for processor */
+ acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
+ ACPI_UINT32_MAX, &longhaul_walk_callback, NULL,
+ NULL, (void *)&pr);
+
+ /* Check ACPI support for C3 state */
+ if (pr != NULL && longhaul_version == TYPE_POWERSAVER) {
+ cx = &pr->power.states[ACPI_STATE_C3];
+ if (cx->address > 0 && cx->latency <= 1000)
+ longhaul_flags |= USE_ACPI_C3;
+ }
+ /* Disable if it isn't working */
+ if (disable_acpi_c3)
+ longhaul_flags &= ~USE_ACPI_C3;
+ /* Check if northbridge is friendly */
+ if (enable_arbiter_disable())
+ longhaul_flags |= USE_NORTHBRIDGE;
+
+ /* Check ACPI support for bus master arbiter disable */
+ if (!(longhaul_flags & USE_ACPI_C3
+ || longhaul_flags & USE_NORTHBRIDGE)
+ && ((pr == NULL) || !(pr->flags.bm_control))) {
+ printk(KERN_ERR PFX
+ "No ACPI support. Unsupported northbridge.\n");
+ return -ENODEV;
+ }
+
+ if (longhaul_flags & USE_NORTHBRIDGE)
+ printk(KERN_INFO PFX "Using northbridge support.\n");
+ if (longhaul_flags & USE_ACPI_C3)
+ printk(KERN_INFO PFX "Using ACPI support.\n");
+
+ ret = longhaul_get_ranges();
+ if (ret != 0)
+ return ret;
+
+ if ((longhaul_version != TYPE_LONGHAUL_V1) && (scale_voltage != 0))
+ longhaul_setup_voltagescaling();
+
+ policy->cpuinfo.transition_latency = 200000; /* nsec */
+
+ return cpufreq_table_validate_and_show(policy, longhaul_table);
+}
+
+static struct cpufreq_driver longhaul_driver = {
+ .verify = cpufreq_generic_frequency_table_verify,
+ .target_index = longhaul_target,
+ .get = longhaul_get,
+ .init = longhaul_cpu_init,
+ .name = "longhaul",
+ .attr = cpufreq_generic_attr,
+};
+
+static const struct x86_cpu_id longhaul_id[] = {
+ { X86_VENDOR_CENTAUR, 6 },
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, longhaul_id);
+
+static int __init longhaul_init(void)
+{
+ struct cpuinfo_x86 *c = &cpu_data(0);
+
+ if (!x86_match_cpu(longhaul_id))
+ return -ENODEV;
+
+ if (!enable) {
+ printk(KERN_ERR PFX "Option \"enable\" not set. Aborting.\n");
+ return -ENODEV;
+ }
+#ifdef CONFIG_SMP
+ if (num_online_cpus() > 1) {
+ printk(KERN_ERR PFX "More than 1 CPU detected, "
+ "longhaul disabled.\n");
+ return -ENODEV;
+ }
+#endif
+#ifdef CONFIG_X86_IO_APIC
+ if (cpu_has_apic) {
+ printk(KERN_ERR PFX "APIC detected. Longhaul is currently "
+ "broken in this configuration.\n");
+ return -ENODEV;
+ }
+#endif
+ switch (c->x86_model) {
+ case 6 ... 9:
+ return cpufreq_register_driver(&longhaul_driver);
+ case 10:
+ printk(KERN_ERR PFX "Use acpi-cpufreq driver for VIA C7\n");
+ default:
+ ;
+ }
+
+ return -ENODEV;
+}
+
+
+static void __exit longhaul_exit(void)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get(0);
+ int i;
+
+ for (i = 0; i < numscales; i++) {
+ if (mults[i] == maxmult) {
+ struct cpufreq_freqs freqs;
+
+ freqs.old = policy->cur;
+ freqs.new = longhaul_table[i].frequency;
+ freqs.flags = 0;
+
+ cpufreq_freq_transition_begin(policy, &freqs);
+ longhaul_setstate(policy, i);
+ cpufreq_freq_transition_end(policy, &freqs, 0);
+ break;
+ }
+ }
+
+ cpufreq_cpu_put(policy);
+ cpufreq_unregister_driver(&longhaul_driver);
+ kfree(longhaul_table);
+}
+
+/* Even if BIOS is exporting ACPI C3 state, and it is used
+ * with success when CPU is idle, this state doesn't
+ * trigger frequency transition in some cases. */
+module_param(disable_acpi_c3, int, 0644);
+MODULE_PARM_DESC(disable_acpi_c3, "Don't use ACPI C3 support");
+/* Change CPU voltage with frequency. Very useful to save
+ * power, but most VIA C3 processors aren't supporting it. */
+module_param(scale_voltage, int, 0644);
+MODULE_PARM_DESC(scale_voltage, "Scale voltage of processor");
+/* Force revision key to 0 for processors which doesn't
+ * support voltage scaling, but are introducing itself as
+ * such. */
+module_param(revid_errata, int, 0644);
+MODULE_PARM_DESC(revid_errata, "Ignore CPU Revision ID");
+/* By default driver is disabled to prevent incompatible
+ * system freeze. */
+module_param(enable, int, 0644);
+MODULE_PARM_DESC(enable, "Enable driver");
+
+MODULE_AUTHOR("Dave Jones");
+MODULE_DESCRIPTION("Longhaul driver for VIA Cyrix processors.");
+MODULE_LICENSE("GPL");
+
+late_initcall(longhaul_init);
+module_exit(longhaul_exit);
Code Review / kvmfornfv.git / blobdiff