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Bug #1359 » powernow.c

polachok, 05/10/2009 09:38 PM

 
/*
* Copyright (c) 2004 Martin V\xe9giard.
* Copyright (c) 2004-2005 Bruno Ducrot
* Copyright (c) 2004 FUKUDA Nobuhiko <nfukuda@spa.is.uec.ac.jp>
* Copyright (c) 2004, 2006 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Juan Romero Pardines and Martin Vegiard.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/* AMD POWERNOW K8 driver */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/sysctl.h>
#include <bus/isa/isa.h>
#include <machine/cpu.h>
#include <machine/pmap.h>
#include <machine/pc/bios.h>
#include <machine/cpufunc.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>

#define PN8_STA_MFID(x) (((x) >> 16) & 0x3f)
#define PN8_STA_MVID(x) (((x) >> 48) & 0x1f)
#define PN8_STA_SFID(x) (((x) >> 8) & 0x3f)

/*
* MSRs and bits used by PowerNow! technology
*/
#define MSR_AMDK7_FIDVID_CTL 0xc0010041
#define MSR_AMDK7_FIDVID_STATUS 0xc0010042
#define AMD_PN_FID_VID 0x06

#define BIOS_START 0xe0000
#define BIOS_LEN 0x20000
#define BIOS_STEP 16

#define PN8_PSB_VERSION 0x14
#define PN8_PSB_TO_RVO(x) ((x) & 0x03)
#define PN8_PSB_TO_IRT(x) (((x) >> 2) & 0x03)
#define PN8_PSB_TO_MVS(x) (((x) >> 4) & 0x03)
#define PN8_PSB_TO_BATT(x) (((x) >> 6) & 0x03)
/* Bitfields used by K8 */
#define PN8_CTR_FID(x) ((x) & 0x3f)
#define PN8_CTR_VID(x) (((x) & 0x1f) << 8)
#define PN8_CTR_PENDING(x) (((x) & 1) << 32)
#define PN8_STA_CFID(x) ((x) & 0x3f)
#define PN8_STA_SFID(x) (((x) >> 8) & 0x3f)
#define PN8_STA_MFID(x) (((x) >> 16) & 0x3f)
#define PN8_STA_PENDING(x) (((x) >> 31) & 0x01)
#define PN8_STA_CVID(x) (((x) >> 32) & 0x1f)
#define PN8_STA_SVID(x) (((x) >> 40) & 0x1f)
#define PN8_STA_MVID(x) (((x) >> 48) & 0x1f)
#define PN8_PLL_LOCK(x) ((x) * 1000/5)
#define WRITE_FIDVID(fid, vid, ctrl) \
wrmsr(MSR_AMDK7_FIDVID_CTL, \
(((ctrl) << 32) | (1ULL << 16) | ((vid) << 8) | (fid)))
#define COUNT_OFF_IRT(irt) DELAY(10 * (1 << (irt)))
#define COUNT_OFF_VST(vst) DELAY(20 * (vst))
#define FID_TO_VCO_FID(fid) \
(((fid) < 8) ? (8 + ((fid) << 1)) : (fid))

#define READ_PENDING_WAIT(status) \
do { \
(status) = rdmsr(MSR_AMDK7_FIDVID_STATUS); \
} while (PN8_STA_PENDING(status))
#define abs(x) ( x < 0 ? -x : x )

#define POWERNOW_MAX_STATES 16

struct k8pnow_state {
int freq;
uint8_t fid;
uint8_t vid;
};

struct k8pnow_cpu_state {
struct k8pnow_state state_table[POWERNOW_MAX_STATES];
unsigned int n_states;
unsigned int sgtc;
unsigned int vst;
unsigned int mvs;
unsigned int pll;
unsigned int rvo;
unsigned int irt;
int low;
};

struct psb_s {
char signature[10]; /* AMDK7PNOW! */
uint8_t version;
uint8_t flags;
uint16_t ttime; /* Min Settling time */
uint8_t reserved;
uint8_t n_pst;
};
struct pst_s {
uint32_t cpuid;
uint8_t pll;
uint8_t fid;
uint8_t vid;
uint8_t n_states;
};

static struct k8pnow_cpu_state *k8pnow_current_state = NULL;
int cpuspeed;

int
k8pnow_states(struct k8pnow_cpu_state *cstate, uint32_t cpusig,
unsigned int fid, unsigned int vid);
int
k8pnow_decode_pst(struct k8pnow_cpu_state *cstate, uint8_t *p);
/*
* Given a set of pair of fid/vid, and number of performance states,
* compute state_table via an insertion sort.
*/
int
k8pnow_decode_pst(struct k8pnow_cpu_state *cstate, uint8_t *p)
{
int i, j, n;
struct k8pnow_state state;
for (n = 0, i = 0; i < cstate->n_states; i++) {
state.fid = *p++;
state.vid = *p++;
/*
* The minimum supported frequency per the data sheet is 800MHz
* The maximum supported frequency is 5000MHz.
*/
state.freq = 800 + state.fid * 100;
j = n;
while (j > 0 && cstate->state_table[j - 1].freq > state.freq) {
memcpy(&cstate->state_table[j],
&cstate->state_table[j - 1],
sizeof(struct k8pnow_state));
--j;
}
memcpy(&cstate->state_table[j], &state,
sizeof(struct k8pnow_state));
n++;
}
return 1;
}

int
k8pnow_states(struct k8pnow_cpu_state *cstate, uint32_t cpusig,
unsigned int fid, unsigned int vid)
{
struct psb_s *psb;
struct pst_s *pst;
uint8_t *p;
int i;
for (p = (u_int8_t *)BIOS_PADDRTOVADDR(BIOS_START);
p < (u_int8_t *)BIOS_PADDRTOVADDR(BIOS_START + BIOS_LEN); p +=
BIOS_STEP) {
if (memcmp(p, "AMDK7PNOW!", 10) == 0) {
kprintf("K7PNOW label found\n");
psb = (struct psb_s *)p;
if (psb->version != PN8_PSB_VERSION)
return 0;
cstate->vst = psb->ttime;
cstate->rvo = PN8_PSB_TO_RVO(psb->reserved);
cstate->irt = PN8_PSB_TO_IRT(psb->reserved);
cstate->mvs = PN8_PSB_TO_MVS(psb->reserved);
cstate->low = PN8_PSB_TO_BATT(psb->reserved);
p+= sizeof(struct psb_s);
for (i = 0; i < psb->n_pst; ++i) {
pst = (struct pst_s *) p;
cstate->pll = pst->pll;
cstate->n_states = pst->n_states;
if (cpusig == pst->cpuid &&
pst->fid == fid && pst->vid == vid) {
return (k8pnow_decode_pst(cstate,
p+= sizeof (struct pst_s)));
}
p += sizeof(struct pst_s) + 2
* cstate->n_states;
}
}
}
return 0;
}

static int
k8_powernow_setperf(unsigned int freq)
{
unsigned int i;
uint64_t status;
uint32_t val;
int cfid, cvid, fid = 0, vid = 0;
int rvo;
struct k8pnow_cpu_state *cstate;
/*
* We dont do a k8pnow_read_pending_wait here, need to ensure that the
* change pending bit isn't stuck,
*/
status = rdmsr(MSR_AMDK7_FIDVID_STATUS);
if (PN8_STA_PENDING(status))
return 1;
cfid = PN8_STA_CFID(status);
cvid = PN8_STA_CVID(status);
cstate = k8pnow_current_state;
//kprintf("%s: cstate->n_states=%d\n", __func__, cstate->n_states);
for (i = 0; i < cstate->n_states; i++) {
if (cstate->state_table[i].freq >= freq) {
//kprintf("%s: freq=%d\n", __func__, freq);
fid = cstate->state_table[i].fid;
vid = cstate->state_table[i].vid;
//kprintf("%s: fid=%d vid=%d\n", __func__, fid, vid);
break;
}
}
if (fid == cfid && vid == cvid) {
cpuspeed = freq;
return 0;
}
/*
* Phase 1: Raise core voltage to requested VID if frequency is
* going up.
*/
while (cvid > vid) {
val = cvid - (1 << cstate->mvs);
WRITE_FIDVID(cfid, (val > 0) ? val : 0, 1ULL);
READ_PENDING_WAIT(status);
cvid = PN8_STA_CVID(status);
COUNT_OFF_VST(cstate->vst);
}

/* ... then raise to voltage + RVO (if required) */
for (rvo = cstate->rvo; rvo > 0 && cvid > 0; --rvo) {
/* XXX It's not clear from spec if we have to do that
* in 0.25 step or in MVS. Therefore do it as it's done
* under Linux */
WRITE_FIDVID(cfid, cvid - 1, 1ULL);
READ_PENDING_WAIT(status);
cvid = PN8_STA_CVID(status);
COUNT_OFF_VST(cstate->vst);
}
/* Phase 2: change to requested core frequency */
if (cfid != fid) {
uint32_t vco_fid, vco_cfid;
vco_fid = FID_TO_VCO_FID(fid);
vco_cfid = FID_TO_VCO_FID(cfid);
while (abs(vco_fid - vco_cfid) > 2) {
if (fid > cfid) {
if (cfid > 6)
val = cfid + 2;
else
val = FID_TO_VCO_FID(cfid) + 2;
} else
val = cfid - 2;
WRITE_FIDVID(val, cvid, (uint64_t)cstate->pll * 1000 / 5);
READ_PENDING_WAIT(status);
cfid = PN8_STA_CFID(status);
COUNT_OFF_IRT(cstate->irt);
vco_cfid = FID_TO_VCO_FID(cfid);
}
WRITE_FIDVID(fid, cvid, (uint64_t) cstate->pll * 1000 / 5);
READ_PENDING_WAIT(status);
cfid = PN8_STA_CFID(status);
COUNT_OFF_IRT(cstate->irt);
}
/* Phase 3: change to requested voltage */
if (cvid != vid) {
WRITE_FIDVID(cfid, vid, 1ULL);
READ_PENDING_WAIT(status);
cvid = PN8_STA_CVID(status);
COUNT_OFF_VST(cstate->vst);
}
if (cfid == fid || cvid == vid)
cpuspeed = cstate->state_table[i].freq;
return 0;
}

static int
powernow_sysctl_helper(SYSCTL_HANDLER_ARGS)
{
int fq, err = 0;
int i;
struct k8pnow_cpu_state *cstate;
struct k8pnow_state *state;
cstate = k8pnow_current_state;
if (req->newptr != NULL) {
err = SYSCTL_IN(req, &fq, sizeof(fq));
if (err)
return err;
if (fq != cpuspeed) {
for (i = cstate->n_states; i > 0; i--) {
state = &cstate->state_table[i-1];
if(fq == state->freq) {
k8_powernow_setperf(fq);
break;
}
}
}
} else {
err = SYSCTL_OUT(req, &cpuspeed, sizeof(cpuspeed));
}
return err;
}

static struct sysctl_ctx_list machdep_powernow_ctx;
static char freqs_available[80];

static int
powernow_init(void)
{
uint64_t status;
size_t len, freq_len;
uint32_t maxfid, maxvid, i;
struct k8pnow_cpu_state *cstate;
struct k8pnow_state *state;
const char *techname;
u_int32_t regs[4];
cpuspeed = 0;
struct sysctl_oid *oid, *leaf;
do_cpuid(0x80000000, regs);
if (regs[0] < 0x80000007)
return 1;
do_cpuid(0x80000007, regs);
if (!(regs[3] & AMD_PN_FID_VID))
return 2;
/* Extended CPUID signature value */
do_cpuid(0x80000001, regs);
cstate = kmalloc(sizeof(struct k8pnow_cpu_state), M_DEVBUF, M_WAITOK);
cstate->n_states = 0;

status = rdmsr(MSR_AMDK7_FIDVID_STATUS);
maxfid = PN8_STA_MFID(status);
maxvid = PN8_STA_MVID(status);

if (PN8_STA_SFID(status) != PN8_STA_MFID(status))
techname = "PowerNow!";
else
techname = "Cool`n'Quiet";

k8pnow_states(cstate, regs[0], maxfid, maxvid);

len = 0;
if (cstate->n_states) {
freq_len = cstate->n_states * (sizeof("9999 ")-1) + 1;
kprintf("%s speeds:",
techname);
for (i = cstate->n_states; i > 0; i--) {
state = &cstate->state_table[i-1];
kprintf(" %d", state->freq);
len += ksnprintf(freqs_available + len, freq_len - len, "%d%s",
state->freq,
i > 1 ? " " : "");

}
kprintf(" MHz\n");
k8pnow_current_state = cstate;
k8_powernow_setperf(cstate->state_table[0].freq);
} else {
kfree(cstate, M_DEVBUF);
kprintf("powernow: no power states found\n");
return 3;
}

/*
* Setup the sysctl sub-tree machdep.powernow.*
*/
oid = SYSCTL_ADD_NODE(&machdep_powernow_ctx,
SYSCTL_STATIC_CHILDREN(_machdep), OID_AUTO, "powernow",
CTLFLAG_RD, NULL, "");
if (oid == NULL)
return(EOPNOTSUPP);
oid = SYSCTL_ADD_NODE(&machdep_powernow_ctx, SYSCTL_CHILDREN(oid),
OID_AUTO, "frequency", CTLFLAG_RD, NULL, "");
if (oid == NULL)
return(EOPNOTSUPP);
leaf = SYSCTL_ADD_PROC(&machdep_powernow_ctx, SYSCTL_CHILDREN(oid),
OID_AUTO, "target", CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
powernow_sysctl_helper, "I",
"Target CPU frequency for AMD PowerNow!");
if (leaf == NULL)
return(EOPNOTSUPP);
leaf = SYSCTL_ADD_PROC(&machdep_powernow_ctx, SYSCTL_CHILDREN(oid),
OID_AUTO, "current", CTLTYPE_INT | CTLFLAG_RD, NULL, 0,
powernow_sysctl_helper, "I",
"Current CPU frequency for AMD PowerNow!");
if (leaf == NULL)
return(EOPNOTSUPP);
leaf = SYSCTL_ADD_STRING(&machdep_powernow_ctx, SYSCTL_CHILDREN(oid),
OID_AUTO, "available", CTLFLAG_RD, freqs_available,
sizeof(freqs_available),
"CPU frequencies supported by AMD PowerNow!");
if (leaf == NULL)
return(EOPNOTSUPP);
return(0);
}

static int
powernow_modevh(struct module *m, int what, void *arg __unused)
{
int error;

switch(what) {
case MOD_LOAD:
error = sysctl_ctx_init(&machdep_powernow_ctx);
if (error != 0)
break;
error = powernow_init();
break;
case MOD_UNLOAD:
if(k8pnow_current_state)
kfree(k8pnow_current_state, M_DEVBUF);
error = sysctl_ctx_free(&machdep_powernow_ctx);
break;
default:
error = EINVAL;
break;
}
return(error);
}
static moduledata_t powernow_mod = {
"powernow",
powernow_modevh,
NULL,
};

DECLARE_MODULE(powernow, powernow_mod, SI_BOOT2_KLD, SI_ORDER_ANY);
(5-5/6)