[PATCH] sem2mutex: misc static one-file mutexes

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / i386 / kernel / cpu / cpufreq / powernow-k8.c

/*
 *   (c) 2003, 2004, 2005 Advanced Micro Devices, Inc.
 *  Your use of this code is subject to the terms and conditions of the
 *  GNU general public license version 2. See "COPYING" or
 *  http://www.gnu.org/licenses/gpl.html
 *
 *  Support : mark.langsdorf@amd.com
 *
 *  Based on the powernow-k7.c module written by Dave Jones.
 *  (C) 2003 Dave Jones <davej@codemonkey.org.uk> on behalf of SuSE Labs
 *  (C) 2004 Dominik Brodowski <linux@brodo.de>
 *  (C) 2004 Pavel Machek <pavel@suse.cz>
 *  Licensed under the terms of the GNU GPL License version 2.
 *  Based upon datasheets & sample CPUs kindly provided by AMD.
 *
 *  Valuable input gratefully received from Dave Jones, Pavel Machek,
 *  Dominik Brodowski, and others.
 *  Originally developed by Paul Devriendt.
 *  Processor information obtained from Chapter 9 (Power and Thermal Management)
 *  of the "BIOS and Kernel Developer's Guide for the AMD Athlon 64 and AMD
 *  Opteron Processors" available for download from www.amd.com
 *
 *  Tables for specific CPUs can be infrerred from
 *     http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/30430.pdf
 */

#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/cpumask.h>
#include <linux/sched.h>        /* for current / set_cpus_allowed() */

#include <asm/msr.h>
#include <asm/io.h>
#include <asm/delay.h>

#ifdef CONFIG_X86_POWERNOW_K8_ACPI
#include <linux/acpi.h>
#include <linux/mutex.h>
#include <acpi/processor.h>
#endif

#define PFX "powernow-k8: "
#define BFX PFX "BIOS error: "
#define VERSION "version 1.60.1"
#include "powernow-k8.h"

/* serialize freq changes  */
static DEFINE_MUTEX(fidvid_mutex);

static struct powernow_k8_data *powernow_data[NR_CPUS];

#ifndef CONFIG_SMP
static cpumask_t cpu_core_map[1] = { CPU_MASK_ALL };
#endif

/* Return a frequency in MHz, given an input fid */
static u32 find_freq_from_fid(u32 fid)
{
        return 800 + (fid * 100);
}

/* Return a frequency in KHz, given an input fid */
static u32 find_khz_freq_from_fid(u32 fid)
{
        return 1000 * find_freq_from_fid(fid);
}

/* Return a voltage in miliVolts, given an input vid */
static u32 find_millivolts_from_vid(struct powernow_k8_data *data, u32 vid)
{
        return 1550-vid*25;
}

/* Return the vco fid for an input fid
 *
 * Each "low" fid has corresponding "high" fid, and you can get to "low" fids
 * only from corresponding high fids. This returns "high" fid corresponding to
 * "low" one.
 */
static u32 convert_fid_to_vco_fid(u32 fid)
{
        if (fid < HI_FID_TABLE_BOTTOM)
                return 8 + (2 * fid);
        else
                return fid;
}

/*
 * Return 1 if the pending bit is set. Unless we just instructed the processor
 * to transition to a new state, seeing this bit set is really bad news.
 */
static int pending_bit_stuck(void)
{
        u32 lo, hi;

        rdmsr(MSR_FIDVID_STATUS, lo, hi);
        return lo & MSR_S_LO_CHANGE_PENDING ? 1 : 0;
}

/*
 * Update the global current fid / vid values from the status msr.
 * Returns 1 on error.
 */
static int query_current_values_with_pending_wait(struct powernow_k8_data *data)
{
        u32 lo, hi;
        u32 i = 0;

        do {
                if (i++ > 10000) {
                        dprintk("detected change pending stuck\n");
                        return 1;
                }
                rdmsr(MSR_FIDVID_STATUS, lo, hi);
        } while (lo & MSR_S_LO_CHANGE_PENDING);

        data->currvid = hi & MSR_S_HI_CURRENT_VID;
        data->currfid = lo & MSR_S_LO_CURRENT_FID;

        return 0;
}

/* the isochronous relief time */
static void count_off_irt(struct powernow_k8_data *data)
{
        udelay((1 << data->irt) * 10);
        return;
}

/* the voltage stabalization time */
static void count_off_vst(struct powernow_k8_data *data)
{
        udelay(data->vstable * VST_UNITS_20US);
        return;
}

/* need to init the control msr to a safe value (for each cpu) */
static void fidvid_msr_init(void)
{
        u32 lo, hi;
        u8 fid, vid;

        rdmsr(MSR_FIDVID_STATUS, lo, hi);
        vid = hi & MSR_S_HI_CURRENT_VID;
        fid = lo & MSR_S_LO_CURRENT_FID;
        lo = fid | (vid << MSR_C_LO_VID_SHIFT);
        hi = MSR_C_HI_STP_GNT_BENIGN;
        dprintk("cpu%d, init lo 0x%x, hi 0x%x\n", smp_processor_id(), lo, hi);
        wrmsr(MSR_FIDVID_CTL, lo, hi);
}


/* write the new fid value along with the other control fields to the msr */
static int write_new_fid(struct powernow_k8_data *data, u32 fid)
{
        u32 lo;
        u32 savevid = data->currvid;
        u32 i = 0;

        if ((fid & INVALID_FID_MASK) || (data->currvid & INVALID_VID_MASK)) {
                printk(KERN_ERR PFX "internal error - overflow on fid write\n");
                return 1;
        }

        lo = fid | (data->currvid << MSR_C_LO_VID_SHIFT) | MSR_C_LO_INIT_FID_VID;

        dprintk("writing fid 0x%x, lo 0x%x, hi 0x%x\n",
                fid, lo, data->plllock * PLL_LOCK_CONVERSION);

        do {
                wrmsr(MSR_FIDVID_CTL, lo, data->plllock * PLL_LOCK_CONVERSION);
                if (i++ > 100) {
                        printk(KERN_ERR PFX "internal error - pending bit very stuck - no further pstate changes possible\n");
                        return 1;
                }
        } while (query_current_values_with_pending_wait(data));

        count_off_irt(data);

        if (savevid != data->currvid) {
                printk(KERN_ERR PFX "vid change on fid trans, old 0x%x, new 0x%x\n",
                       savevid, data->currvid);
                return 1;
        }

        if (fid != data->currfid) {
                printk(KERN_ERR PFX "fid trans failed, fid 0x%x, curr 0x%x\n", fid,
                        data->currfid);
                return 1;
        }

        return 0;
}

/* Write a new vid to the hardware */
static int write_new_vid(struct powernow_k8_data *data, u32 vid)
{
        u32 lo;
        u32 savefid = data->currfid;
        int i = 0;

        if ((data->currfid & INVALID_FID_MASK) || (vid & INVALID_VID_MASK)) {
                printk(KERN_ERR PFX "internal error - overflow on vid write\n");
                return 1;
        }

        lo = data->currfid | (vid << MSR_C_LO_VID_SHIFT) | MSR_C_LO_INIT_FID_VID;

        dprintk("writing vid 0x%x, lo 0x%x, hi 0x%x\n",
                vid, lo, STOP_GRANT_5NS);

        do {
                wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
                if (i++ > 100) {
                        printk(KERN_ERR PFX "internal error - pending bit very stuck - no further pstate changes possible\n");
                        return 1;
                }
        } while (query_current_values_with_pending_wait(data));

        if (savefid != data->currfid) {
                printk(KERN_ERR PFX "fid changed on vid trans, old 0x%x new 0x%x\n",
                       savefid, data->currfid);
                return 1;
        }

        if (vid != data->currvid) {
                printk(KERN_ERR PFX "vid trans failed, vid 0x%x, curr 0x%x\n", vid,
                                data->currvid);
                return 1;
        }

        return 0;
}

/*
 * Reduce the vid by the max of step or reqvid.
 * Decreasing vid codes represent increasing voltages:
 * vid of 0 is 1.550V, vid of 0x1e is 0.800V, vid of VID_OFF is off.
 */
static int decrease_vid_code_by_step(struct powernow_k8_data *data, u32 reqvid, u32 step)
{
        if ((data->currvid - reqvid) > step)
                reqvid = data->currvid - step;

        if (write_new_vid(data, reqvid))
                return 1;

        count_off_vst(data);

        return 0;
}

/* Change the fid and vid, by the 3 phases. */
static int transition_fid_vid(struct powernow_k8_data *data, u32 reqfid, u32 reqvid)
{
        if (core_voltage_pre_transition(data, reqvid))
                return 1;

        if (core_frequency_transition(data, reqfid))
                return 1;

        if (core_voltage_post_transition(data, reqvid))
                return 1;

        if (query_current_values_with_pending_wait(data))
                return 1;

        if ((reqfid != data->currfid) || (reqvid != data->currvid)) {
                printk(KERN_ERR PFX "failed (cpu%d): req 0x%x 0x%x, curr 0x%x 0x%x\n",
                                smp_processor_id(),
                                reqfid, reqvid, data->currfid, data->currvid);
                return 1;
        }

        dprintk("transitioned (cpu%d): new fid 0x%x, vid 0x%x\n",
                smp_processor_id(), data->currfid, data->currvid);

        return 0;
}

/* Phase 1 - core voltage transition ... setup voltage */
static int core_voltage_pre_transition(struct powernow_k8_data *data, u32 reqvid)
{
        u32 rvosteps = data->rvo;
        u32 savefid = data->currfid;
        u32 maxvid, lo;

        dprintk("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, reqvid 0x%x, rvo 0x%x\n",
                smp_processor_id(),
                data->currfid, data->currvid, reqvid, data->rvo);

        rdmsr(MSR_FIDVID_STATUS, lo, maxvid);
        maxvid = 0x1f & (maxvid >> 16);
        dprintk("ph1 maxvid=0x%x\n", maxvid);
        if (reqvid < maxvid) /* lower numbers are higher voltages */
                reqvid = maxvid;

        while (data->currvid > reqvid) {
                dprintk("ph1: curr 0x%x, req vid 0x%x\n",
                        data->currvid, reqvid);
                if (decrease_vid_code_by_step(data, reqvid, data->vidmvs))
                        return 1;
        }

        while ((rvosteps > 0) && ((data->rvo + data->currvid) > reqvid)) {
                if (data->currvid == maxvid) {
                        rvosteps = 0;
                } else {
                        dprintk("ph1: changing vid for rvo, req 0x%x\n",
                                data->currvid - 1);
                        if (decrease_vid_code_by_step(data, data->currvid - 1, 1))
                                return 1;
                        rvosteps--;
                }
        }

        if (query_current_values_with_pending_wait(data))
                return 1;

        if (savefid != data->currfid) {
                printk(KERN_ERR PFX "ph1 err, currfid changed 0x%x\n", data->currfid);
                return 1;
        }

        dprintk("ph1 complete, currfid 0x%x, currvid 0x%x\n",
                data->currfid, data->currvid);

        return 0;
}

/* Phase 2 - core frequency transition */
static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid)
{
        u32 vcoreqfid, vcocurrfid, vcofiddiff, fid_interval, savevid = data->currvid;

        if ((reqfid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
                printk(KERN_ERR PFX "ph2: illegal lo-lo transition 0x%x 0x%x\n",
                        reqfid, data->currfid);
                return 1;
        }

        if (data->currfid == reqfid) {
                printk(KERN_ERR PFX "ph2 null fid transition 0x%x\n", data->currfid);
                return 0;
        }

        dprintk("ph2 (cpu%d): starting, currfid 0x%x, currvid 0x%x, reqfid 0x%x\n",
                smp_processor_id(),
                data->currfid, data->currvid, reqfid);

        vcoreqfid = convert_fid_to_vco_fid(reqfid);
        vcocurrfid = convert_fid_to_vco_fid(data->currfid);
        vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
            : vcoreqfid - vcocurrfid;

        while (vcofiddiff > 2) {
                (data->currfid & 1) ? (fid_interval = 1) : (fid_interval = 2);

                if (reqfid > data->currfid) {
                        if (data->currfid > LO_FID_TABLE_TOP) {
                                if (write_new_fid(data, data->currfid + fid_interval)) {
                                        return 1;
                                }
                        } else {
                                if (write_new_fid
                                    (data, 2 + convert_fid_to_vco_fid(data->currfid))) {
                                        return 1;
                                }
                        }
                } else {
                        if (write_new_fid(data, data->currfid - fid_interval))
                                return 1;
                }

                vcocurrfid = convert_fid_to_vco_fid(data->currfid);
                vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
                    : vcoreqfid - vcocurrfid;
        }

        if (write_new_fid(data, reqfid))
                return 1;

        if (query_current_values_with_pending_wait(data))
                return 1;

        if (data->currfid != reqfid) {
                printk(KERN_ERR PFX
                        "ph2: mismatch, failed fid transition, curr 0x%x, req 0x%x\n",
                        data->currfid, reqfid);
                return 1;
        }

        if (savevid != data->currvid) {
                printk(KERN_ERR PFX "ph2: vid changed, save 0x%x, curr 0x%x\n",
                        savevid, data->currvid);
                return 1;
        }

        dprintk("ph2 complete, currfid 0x%x, currvid 0x%x\n",
                data->currfid, data->currvid);

        return 0;
}

/* Phase 3 - core voltage transition flow ... jump to the final vid. */
static int core_voltage_post_transition(struct powernow_k8_data *data, u32 reqvid)
{
        u32 savefid = data->currfid;
        u32 savereqvid = reqvid;

        dprintk("ph3 (cpu%d): starting, currfid 0x%x, currvid 0x%x\n",
                smp_processor_id(),
                data->currfid, data->currvid);

        if (reqvid != data->currvid) {
                if (write_new_vid(data, reqvid))
                        return 1;

                if (savefid != data->currfid) {
                        printk(KERN_ERR PFX
                               "ph3: bad fid change, save 0x%x, curr 0x%x\n",
                               savefid, data->currfid);
                        return 1;
                }

                if (data->currvid != reqvid) {
                        printk(KERN_ERR PFX
                               "ph3: failed vid transition\n, req 0x%x, curr 0x%x",
                               reqvid, data->currvid);
                        return 1;
                }
        }

        if (query_current_values_with_pending_wait(data))
                return 1;

        if (savereqvid != data->currvid) {
                dprintk("ph3 failed, currvid 0x%x\n", data->currvid);
                return 1;
        }

        if (savefid != data->currfid) {
                dprintk("ph3 failed, currfid changed 0x%x\n",
                        data->currfid);
                return 1;
        }

        dprintk("ph3 complete, currfid 0x%x, currvid 0x%x\n",
                data->currfid, data->currvid);

        return 0;
}

static int check_supported_cpu(unsigned int cpu)
{
        cpumask_t oldmask = CPU_MASK_ALL;
        u32 eax, ebx, ecx, edx;
        unsigned int rc = 0;

        oldmask = current->cpus_allowed;
        set_cpus_allowed(current, cpumask_of_cpu(cpu));

        if (smp_processor_id() != cpu) {
                printk(KERN_ERR PFX "limiting to cpu %u failed\n", cpu);
                goto out;
        }

        if (current_cpu_data.x86_vendor != X86_VENDOR_AMD)
                goto out;

        eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
        if ((eax & CPUID_XFAM) != CPUID_XFAM_K8)
                goto out;

        if (((eax & CPUID_USE_XFAM_XMOD) != CPUID_USE_XFAM_XMOD) ||
            ((eax & CPUID_XMOD) > CPUID_XMOD_REV_G)) {
                printk(KERN_INFO PFX "Processor cpuid %x not supported\n", eax);
                goto out;
        }

        eax = cpuid_eax(CPUID_GET_MAX_CAPABILITIES);
        if (eax < CPUID_FREQ_VOLT_CAPABILITIES) {
                printk(KERN_INFO PFX
                       "No frequency change capabilities detected\n");
                goto out;
        }

        cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
        if ((edx & P_STATE_TRANSITION_CAPABLE) != P_STATE_TRANSITION_CAPABLE) {
                printk(KERN_INFO PFX "Power state transitions not supported\n");
                goto out;
        }

        rc = 1;

out:
        set_cpus_allowed(current, oldmask);
        return rc;
}

static int check_pst_table(struct powernow_k8_data *data, struct pst_s *pst, u8 maxvid)
{
        unsigned int j;
        u8 lastfid = 0xff;

        for (j = 0; j < data->numps; j++) {
                if (pst[j].vid > LEAST_VID) {
                        printk(KERN_ERR PFX "vid %d invalid : 0x%x\n", j, pst[j].vid);
                        return -EINVAL;
                }
                if (pst[j].vid < data->rvo) {   /* vid + rvo >= 0 */
                        printk(KERN_ERR BFX "0 vid exceeded with pstate %d\n", j);
                        return -ENODEV;
                }
                if (pst[j].vid < maxvid + data->rvo) {  /* vid + rvo >= maxvid */
                        printk(KERN_ERR BFX "maxvid exceeded with pstate %d\n", j);
                        return -ENODEV;
                }
                if (pst[j].fid > MAX_FID) {
                        printk(KERN_ERR BFX "maxfid exceeded with pstate %d\n", j);
                        return -ENODEV;
                }
                if (j && (pst[j].fid < HI_FID_TABLE_BOTTOM)) {
                        /* Only first fid is allowed to be in "low" range */
                        printk(KERN_ERR BFX "two low fids - %d : 0x%x\n", j, pst[j].fid);
                        return -EINVAL;
                }
                if (pst[j].fid < lastfid)
                        lastfid = pst[j].fid;
        }
        if (lastfid & 1) {
                printk(KERN_ERR BFX "lastfid invalid\n");
                return -EINVAL;
        }
        if (lastfid > LO_FID_TABLE_TOP)
                printk(KERN_INFO BFX  "first fid not from lo freq table\n");

        return 0;
}

static void print_basics(struct powernow_k8_data *data)
{
        int j;
        for (j = 0; j < data->numps; j++) {
                if (data->powernow_table[j].frequency != CPUFREQ_ENTRY_INVALID)
                        printk(KERN_INFO PFX "   %d : fid 0x%x (%d MHz), vid 0x%x (%d mV)\n", j,
                                data->powernow_table[j].index & 0xff,
                                data->powernow_table[j].frequency/1000,
                                data->powernow_table[j].index >> 8,
                                find_millivolts_from_vid(data, data->powernow_table[j].index >> 8));
        }
        if (data->batps)
                printk(KERN_INFO PFX "Only %d pstates on battery\n", data->batps);
}

static int fill_powernow_table(struct powernow_k8_data *data, struct pst_s *pst, u8 maxvid)
{
        struct cpufreq_frequency_table *powernow_table;
        unsigned int j;

        if (data->batps) {    /* use ACPI support to get full speed on mains power */
                printk(KERN_WARNING PFX "Only %d pstates usable (use ACPI driver for full range\n", data->batps);
                data->numps = data->batps;
        }

        for ( j=1; j<data->numps; j++ ) {
                if (pst[j-1].fid >= pst[j].fid) {
                        printk(KERN_ERR PFX "PST out of sequence\n");
                        return -EINVAL;
                }
        }

        if (data->numps < 2) {
                printk(KERN_ERR PFX "no p states to transition\n");
                return -ENODEV;
        }

        if (check_pst_table(data, pst, maxvid))
                return -EINVAL;

        powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
                * (data->numps + 1)), GFP_KERNEL);
        if (!powernow_table) {
                printk(KERN_ERR PFX "powernow_table memory alloc failure\n");
                return -ENOMEM;
        }

        for (j = 0; j < data->numps; j++) {
                powernow_table[j].index = pst[j].fid; /* lower 8 bits */
                powernow_table[j].index |= (pst[j].vid << 8); /* upper 8 bits */
                powernow_table[j].frequency = find_khz_freq_from_fid(pst[j].fid);
        }
        powernow_table[data->numps].frequency = CPUFREQ_TABLE_END;
        powernow_table[data->numps].index = 0;

        if (query_current_values_with_pending_wait(data)) {
                kfree(powernow_table);
                return -EIO;
        }

        dprintk("cfid 0x%x, cvid 0x%x\n", data->currfid, data->currvid);
        data->powernow_table = powernow_table;
        print_basics(data);

        for (j = 0; j < data->numps; j++)
                if ((pst[j].fid==data->currfid) && (pst[j].vid==data->currvid))
                        return 0;

        dprintk("currfid/vid do not match PST, ignoring\n");
        return 0;
}

/* Find and validate the PSB/PST table in BIOS. */
static int find_psb_table(struct powernow_k8_data *data)
{
        struct psb_s *psb;
        unsigned int i;
        u32 mvs;
        u8 maxvid;
        u32 cpst = 0;
        u32 thiscpuid;

        for (i = 0xc0000; i < 0xffff0; i += 0x10) {
                /* Scan BIOS looking for the signature. */
                /* It can not be at ffff0 - it is too big. */

                psb = phys_to_virt(i);
                if (memcmp(psb, PSB_ID_STRING, PSB_ID_STRING_LEN) != 0)
                        continue;

                dprintk("found PSB header at 0x%p\n", psb);

                dprintk("table vers: 0x%x\n", psb->tableversion);
                if (psb->tableversion != PSB_VERSION_1_4) {
                        printk(KERN_ERR BFX "PSB table is not v1.4\n");
                        return -ENODEV;
                }

                dprintk("flags: 0x%x\n", psb->flags1);
                if (psb->flags1) {
                        printk(KERN_ERR BFX "unknown flags\n");
                        return -ENODEV;
                }

                data->vstable = psb->vstable;
                dprintk("voltage stabilization time: %d(*20us)\n", data->vstable);

                dprintk("flags2: 0x%x\n", psb->flags2);
                data->rvo = psb->flags2 & 3;
                data->irt = ((psb->flags2) >> 2) & 3;
                mvs = ((psb->flags2) >> 4) & 3;
                data->vidmvs = 1 << mvs;
                data->batps = ((psb->flags2) >> 6) & 3;

                dprintk("ramp voltage offset: %d\n", data->rvo);
                dprintk("isochronous relief time: %d\n", data->irt);
                dprintk("maximum voltage step: %d - 0x%x\n", mvs, data->vidmvs);

                dprintk("numpst: 0x%x\n", psb->num_tables);
                cpst = psb->num_tables;
                if ((psb->cpuid == 0x00000fc0) || (psb->cpuid == 0x00000fe0) ){
                        thiscpuid = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
                        if ((thiscpuid == 0x00000fc0) || (thiscpuid == 0x00000fe0) ) {
                                cpst = 1;
                        }
                }
                if (cpst != 1) {
                        printk(KERN_ERR BFX "numpst must be 1\n");
                        return -ENODEV;
                }

                data->plllock = psb->plllocktime;
                dprintk("plllocktime: 0x%x (units 1us)\n", psb->plllocktime);
                dprintk("maxfid: 0x%x\n", psb->maxfid);
                dprintk("maxvid: 0x%x\n", psb->maxvid);
                maxvid = psb->maxvid;

                data->numps = psb->numps;
                dprintk("numpstates: 0x%x\n", data->numps);
                return fill_powernow_table(data, (struct pst_s *)(psb+1), maxvid);
        }
        /*
         * If you see this message, complain to BIOS manufacturer. If
         * he tells you "we do not support Linux" or some similar
         * nonsense, remember that Windows 2000 uses the same legacy
         * mechanism that the old Linux PSB driver uses. Tell them it
         * is broken with Windows 2000.
         *
         * The reference to the AMD documentation is chapter 9 in the
         * BIOS and Kernel Developer's Guide, which is available on
         * www.amd.com
         */
        printk(KERN_ERR PFX "BIOS error - no PSB or ACPI _PSS objects\n");
        return -ENODEV;
}

#ifdef CONFIG_X86_POWERNOW_K8_ACPI
static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index)
{
        if (!data->acpi_data.state_count)
                return;

        data->irt = (data->acpi_data.states[index].control >> IRT_SHIFT) & IRT_MASK;
        data->rvo = (data->acpi_data.states[index].control >> RVO_SHIFT) & RVO_MASK;
        data->exttype = (data->acpi_data.states[index].control >> EXT_TYPE_SHIFT) & EXT_TYPE_MASK;
        data->plllock = (data->acpi_data.states[index].control >> PLL_L_SHIFT) & PLL_L_MASK;
        data->vidmvs = 1 << ((data->acpi_data.states[index].control >> MVS_SHIFT) & MVS_MASK);
        data->vstable = (data->acpi_data.states[index].control >> VST_SHIFT) & VST_MASK;
}

static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
{
        int i;
        int cntlofreq = 0;
        struct cpufreq_frequency_table *powernow_table;

        if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
                dprintk("register performance failed: bad ACPI data\n");
                return -EIO;
        }

        /* verify the data contained in the ACPI structures */
        if (data->acpi_data.state_count <= 1) {
                dprintk("No ACPI P-States\n");
                goto err_out;
        }

        if ((data->acpi_data.control_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) ||
                (data->acpi_data.status_register.space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
                dprintk("Invalid control/status registers (%x - %x)\n",
                        data->acpi_data.control_register.space_id,
                        data->acpi_data.status_register.space_id);
                goto err_out;
        }

        /* fill in data->powernow_table */
        powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table)
                * (data->acpi_data.state_count + 1)), GFP_KERNEL);
        if (!powernow_table) {
                dprintk("powernow_table memory alloc failure\n");
                goto err_out;
        }

        for (i = 0; i < data->acpi_data.state_count; i++) {
                u32 fid;
                u32 vid;

                if (data->exttype) {
                        fid = data->acpi_data.states[i].status & FID_MASK;
                        vid = (data->acpi_data.states[i].status >> VID_SHIFT) & VID_MASK;
                } else {
                        fid = data->acpi_data.states[i].control & FID_MASK;
                        vid = (data->acpi_data.states[i].control >> VID_SHIFT) & VID_MASK;
                }

                dprintk("   %d : fid 0x%x, vid 0x%x\n", i, fid, vid);

                powernow_table[i].index = fid; /* lower 8 bits */
                powernow_table[i].index |= (vid << 8); /* upper 8 bits */
                powernow_table[i].frequency = find_khz_freq_from_fid(fid);

                /* verify frequency is OK */
                if ((powernow_table[i].frequency > (MAX_FREQ * 1000)) ||
                        (powernow_table[i].frequency < (MIN_FREQ * 1000))) {
                        dprintk("invalid freq %u kHz, ignoring\n", powernow_table[i].frequency);
                        powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
                        continue;
                }

                /* verify voltage is OK - BIOSs are using "off" to indicate invalid */
                if (vid == VID_OFF) {
                        dprintk("invalid vid %u, ignoring\n", vid);
                        powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
                        continue;
                }

                /* verify only 1 entry from the lo frequency table */
                if (fid < HI_FID_TABLE_BOTTOM) {
                        if (cntlofreq) {
                                /* if both entries are the same, ignore this one ... */
                                if ((powernow_table[i].frequency != powernow_table[cntlofreq].frequency) ||
                                    (powernow_table[i].index != powernow_table[cntlofreq].index)) {
                                        printk(KERN_ERR PFX "Too many lo freq table entries\n");
                                        goto err_out_mem;
                                }

                                dprintk("double low frequency table entry, ignoring it.\n");
                                powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
                                continue;
                        } else
                                cntlofreq = i;
                }

                if (powernow_table[i].frequency != (data->acpi_data.states[i].core_frequency * 1000)) {
                        printk(KERN_INFO PFX "invalid freq entries %u kHz vs. %u kHz\n",
                                powernow_table[i].frequency,
                                (unsigned int) (data->acpi_data.states[i].core_frequency * 1000));
                        powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
                        continue;
                }
        }

        powernow_table[data->acpi_data.state_count].frequency = CPUFREQ_TABLE_END;
        powernow_table[data->acpi_data.state_count].index = 0;
        data->powernow_table = powernow_table;

        /* fill in data */
        data->numps = data->acpi_data.state_count;
        print_basics(data);
        powernow_k8_acpi_pst_values(data, 0);

        /* notify BIOS that we exist */
        acpi_processor_notify_smm(THIS_MODULE);

        return 0;

err_out_mem:
        kfree(powernow_table);

err_out:
        acpi_processor_unregister_performance(&data->acpi_data, data->cpu);

        /* data->acpi_data.state_count informs us at ->exit() whether ACPI was used */
        data->acpi_data.state_count = 0;

        return -ENODEV;
}

static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data)
{
        if (data->acpi_data.state_count)
                acpi_processor_unregister_performance(&data->acpi_data, data->cpu);
}

#else
static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data) { return -ENODEV; }
static void powernow_k8_cpu_exit_acpi(struct powernow_k8_data *data) { return; }
static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index) { return; }
#endif /* CONFIG_X86_POWERNOW_K8_ACPI */

/* Take a frequency, and issue the fid/vid transition command */
static int transition_frequency(struct powernow_k8_data *data, unsigned int index)
{
        u32 fid;
        u32 vid;
        int res, i;
        struct cpufreq_freqs freqs;

        dprintk("cpu %d transition to index %u\n", smp_processor_id(), index);

        /* fid are the lower 8 bits of the index we stored into
         * the cpufreq frequency table in find_psb_table, vid are
         * the upper 8 bits.
         */

        fid = data->powernow_table[index].index & 0xFF;
        vid = (data->powernow_table[index].index & 0xFF00) >> 8;

        dprintk("table matched fid 0x%x, giving vid 0x%x\n", fid, vid);

        if (query_current_values_with_pending_wait(data))
                return 1;

        if ((data->currvid == vid) && (data->currfid == fid)) {
                dprintk("target matches current values (fid 0x%x, vid 0x%x)\n",
                        fid, vid);
                return 0;
        }

        if ((fid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
                printk(KERN_ERR PFX
                       "ignoring illegal change in lo freq table-%x to 0x%x\n",
                       data->currfid, fid);
                return 1;
        }

        dprintk("cpu %d, changing to fid 0x%x, vid 0x%x\n",
                smp_processor_id(), fid, vid);

        freqs.cpu = data->cpu;
        freqs.old = find_khz_freq_from_fid(data->currfid);
        freqs.new = find_khz_freq_from_fid(fid);
        for_each_cpu_mask(i, cpu_core_map[data->cpu]) {
                freqs.cpu = i;
                cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
        }

        res = transition_fid_vid(data, fid, vid);

        freqs.new = find_khz_freq_from_fid(data->currfid);
        for_each_cpu_mask(i, cpu_core_map[data->cpu]) {
                freqs.cpu = i;
                cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
        }
        return res;
}

/* Driver entry point to switch to the target frequency */
static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsigned relation)
{
        cpumask_t oldmask = CPU_MASK_ALL;
        struct powernow_k8_data *data = powernow_data[pol->cpu];
        u32 checkfid = data->currfid;
        u32 checkvid = data->currvid;
        unsigned int newstate;
        int ret = -EIO;

        /* only run on specific CPU from here on */
        oldmask = current->cpus_allowed;
        set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));

        if (smp_processor_id() != pol->cpu) {
                printk(KERN_ERR PFX "limiting to cpu %u failed\n", pol->cpu);
                goto err_out;
        }

        if (pending_bit_stuck()) {
                printk(KERN_ERR PFX "failing targ, change pending bit set\n");
                goto err_out;
        }

        dprintk("targ: cpu %d, %d kHz, min %d, max %d, relation %d\n",
                pol->cpu, targfreq, pol->min, pol->max, relation);

        if (query_current_values_with_pending_wait(data)) {
                ret = -EIO;
                goto err_out;
        }

        dprintk("targ: curr fid 0x%x, vid 0x%x\n",
                data->currfid, data->currvid);

        if ((checkvid != data->currvid) || (checkfid != data->currfid)) {
                printk(KERN_INFO PFX
                        "error - out of sync, fix 0x%x 0x%x, vid 0x%x 0x%x\n",
                        checkfid, data->currfid, checkvid, data->currvid);
        }

        if (cpufreq_frequency_table_target(pol, data->powernow_table, targfreq, relation, &newstate))
                goto err_out;

        mutex_lock(&fidvid_mutex);

        powernow_k8_acpi_pst_values(data, newstate);

        if (transition_frequency(data, newstate)) {
                printk(KERN_ERR PFX "transition frequency failed\n");
                ret = 1;
                mutex_unlock(&fidvid_mutex);
                goto err_out;
        }
        mutex_unlock(&fidvid_mutex);

        pol->cur = find_khz_freq_from_fid(data->currfid);
        ret = 0;

err_out:
        set_cpus_allowed(current, oldmask);
        return ret;
}

/* Driver entry point to verify the policy and range of frequencies */
static int powernowk8_verify(struct cpufreq_policy *pol)
{
        struct powernow_k8_data *data = powernow_data[pol->cpu];

        return cpufreq_frequency_table_verify(pol, data->powernow_table);
}

/* per CPU init entry point to the driver */
static int __cpuinit powernowk8_cpu_init(struct cpufreq_policy *pol)
{
        struct powernow_k8_data *data;
        cpumask_t oldmask = CPU_MASK_ALL;
        int rc, i;

        if (!cpu_online(pol->cpu))
                return -ENODEV;

        if (!check_supported_cpu(pol->cpu))
                return -ENODEV;

        data = kzalloc(sizeof(struct powernow_k8_data), GFP_KERNEL);
        if (!data) {
                printk(KERN_ERR PFX "unable to alloc powernow_k8_data");
                return -ENOMEM;
        }

        data->cpu = pol->cpu;

        if (powernow_k8_cpu_init_acpi(data)) {
                /*
                 * Use the PSB BIOS structure. This is only availabe on
                 * an UP version, and is deprecated by AMD.
                 */

                if ((num_online_cpus() != 1) || (num_possible_cpus() != 1)) {
                        printk(KERN_ERR PFX "MP systems not supported by PSB BIOS structure\n");
                        kfree(data);
                        return -ENODEV;
                }
                if (pol->cpu != 0) {
                        printk(KERN_ERR PFX "init not cpu 0\n");
                        kfree(data);
                        return -ENODEV;
                }
                rc = find_psb_table(data);
                if (rc) {
                        kfree(data);
                        return -ENODEV;
                }
        }

        /* only run on specific CPU from here on */
        oldmask = current->cpus_allowed;
        set_cpus_allowed(current, cpumask_of_cpu(pol->cpu));

        if (smp_processor_id() != pol->cpu) {
                printk(KERN_ERR PFX "limiting to cpu %u failed\n", pol->cpu);
                goto err_out;
        }

        if (pending_bit_stuck()) {
                printk(KERN_ERR PFX "failing init, change pending bit set\n");
                goto err_out;
        }

        if (query_current_values_with_pending_wait(data))
                goto err_out;

        fidvid_msr_init();

        /* run on any CPU again */
        set_cpus_allowed(current, oldmask);

        pol->governor = CPUFREQ_DEFAULT_GOVERNOR;
        pol->cpus = cpu_core_map[pol->cpu];

        /* Take a crude guess here.
         * That guess was in microseconds, so multiply with 1000 */
        pol->cpuinfo.transition_latency = (((data->rvo + 8) * data->vstable * VST_UNITS_20US)
            + (3 * (1 << data->irt) * 10)) * 1000;

        pol->cur = find_khz_freq_from_fid(data->currfid);
        dprintk("policy current frequency %d kHz\n", pol->cur);

        /* min/max the cpu is capable of */
        if (cpufreq_frequency_table_cpuinfo(pol, data->powernow_table)) {
                printk(KERN_ERR PFX "invalid powernow_table\n");
                powernow_k8_cpu_exit_acpi(data);
                kfree(data->powernow_table);
                kfree(data);
                return -EINVAL;
        }

        cpufreq_frequency_table_get_attr(data->powernow_table, pol->cpu);

        printk("cpu_init done, current fid 0x%x, vid 0x%x\n",
               data->currfid, data->currvid);

        for_each_cpu_mask(i, cpu_core_map[pol->cpu])
                powernow_data[i] = data;

        return 0;

err_out:
        set_cpus_allowed(current, oldmask);
        powernow_k8_cpu_exit_acpi(data);

        kfree(data);
        return -ENODEV;
}

static int __devexit powernowk8_cpu_exit (struct cpufreq_policy *pol)
{
        struct powernow_k8_data *data = powernow_data[pol->cpu];

        if (!data)
                return -EINVAL;

        powernow_k8_cpu_exit_acpi(data);

        cpufreq_frequency_table_put_attr(pol->cpu);

        kfree(data->powernow_table);
        kfree(data);

        return 0;
}

static unsigned int powernowk8_get (unsigned int cpu)
{
        struct powernow_k8_data *data = powernow_data[cpu];
        cpumask_t oldmask = current->cpus_allowed;
        unsigned int khz = 0;

        set_cpus_allowed(current, cpumask_of_cpu(cpu));
        if (smp_processor_id() != cpu) {
                printk(KERN_ERR PFX "limiting to CPU %d failed in powernowk8_get\n", cpu);
                set_cpus_allowed(current, oldmask);
                return 0;
        }

        if (query_current_values_with_pending_wait(data))
                goto out;

        khz = find_khz_freq_from_fid(data->currfid);

out:
        set_cpus_allowed(current, oldmask);
        return khz;
}

static struct freq_attr* powernow_k8_attr[] = {
        &cpufreq_freq_attr_scaling_available_freqs,
        NULL,
};

static struct cpufreq_driver cpufreq_amd64_driver = {
        .verify = powernowk8_verify,
        .target = powernowk8_target,
        .init = powernowk8_cpu_init,
        .exit = __devexit_p(powernowk8_cpu_exit),
        .get = powernowk8_get,
        .name = "powernow-k8",
        .owner = THIS_MODULE,
        .attr = powernow_k8_attr,
};

/* driver entry point for init */
static int __cpuinit powernowk8_init(void)
{
        unsigned int i, supported_cpus = 0;

        for_each_online_cpu(i) {
                if (check_supported_cpu(i))
                        supported_cpus++;
        }

        if (supported_cpus == num_online_cpus()) {
                printk(KERN_INFO PFX "Found %d AMD Athlon 64 / Opteron "
                        "processors (" VERSION ")\n", supported_cpus);
                return cpufreq_register_driver(&cpufreq_amd64_driver);
        }

        return -ENODEV;
}

/* driver entry point for term */
static void __exit powernowk8_exit(void)
{
        dprintk("exit\n");

        cpufreq_unregister_driver(&cpufreq_amd64_driver);
}

MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com> and Mark Langsdorf <mark.langsdorf@amd.com>");
MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
MODULE_LICENSE("GPL");

late_initcall(powernowk8_init);
module_exit(powernowk8_exit);