/*
* (c) 2003 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 : paul.devriendt@amd.com
*
* Based on the powernow-k7.c module written by Dave Jones.
* (C) 2003 Dave Jones <davej@codemonkey.ork.uk> on behalf of SuSE Labs
* Licensed under the terms of the GNU GPL License version 2.
* Based upon datasheets & sample CPUs kindly provided by AMD.
*
* 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", revision 3.03, available for download from www.amd.com
*
*/
#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 <asm/msr.h>
#include <asm/io.h>
#include <asm/delay.h>
#define PFX "powernow-k8: "
#define BFX PFX "BIOS error: "
#define VERSION "version 1.00.08a"
#include "powernow-k8.h"
#ifdef CONFIG_PREEMPT
#warning this driver has not been tested on a preempt system
#endif
static u32 vstable; /* voltage stabalization time, from PSB, units 20 us */
static u32 plllock; /* pll lock time, from PSB, units 1 us */
static u32 numps; /* number of p-states, from PSB */
static u32 rvo; /* ramp voltage offset, from PSB */
static u32 irt; /* isochronous relief time, from PSB */
static u32 vidmvs; /* usable value calculated from mvs, from PSB */
static u32 currvid; /* keep track of the current fid / vid */
static u32 currfid;
static struct cpufreq_frequency_table *powernow_table;
/*
The PSB table supplied by BIOS allows for the definition of the number of
p-states that can be used when running on a/c, and the number of p-states
that can be used when running on battery. This allows laptop manufacturers
to force the system to save power when running from battery. The relationship
is :
1 <= number_of_battery_p_states <= maximum_number_of_p_states
This driver does NOT have the support in it to detect transitions from
a/c power to battery power, and thus trigger the transition to a lower
p-state if required. This is because I need ACPI and the 2.6 kernel to do
this, and this is a 2.4 kernel driver. Check back for a new improved driver
for the 2.6 kernel soon.
This code therefore assumes it is on battery at all times, and thus
restricts performance to number_of_battery_p_states. For desktops,
number_of_battery_p_states == maximum_number_of_pstates,
so this is not actually a restriction.
*/
static u32 batps; /* limit on the number of p states when on battery */
/* - set by BIOS in the PSB/PST */
/* Return a frequency in MHz, given an input fid */
static u32 find_freq_from_fid(u32 fid)
{
return 800 + (fid * 100);
}
/* Return the vco fid for an input fid */
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 are actually just told the
* processor to transition a state, seeing this bit set is really bad news.
*/
static inline 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(void)
{
u32 lo, hi;
u32 i = 0;
lo = MSR_S_LO_CHANGE_PENDING;
while (lo & MSR_S_LO_CHANGE_PENDING) {
if (i++ > 0x1000000) {
printk(KERN_ERR PFX "detected change pending stuck\n");
return 1;
}
rdmsr(MSR_FIDVID_STATUS, lo, hi);
}
currvid = hi & MSR_S_HI_CURRENT_VID;
currfid = lo & MSR_S_LO_CURRENT_FID;
return 0;
}
/* the isochronous relief time */
static inline void
count_off_irt(void)
{
udelay((1 << irt) * 10);
return;
}
/* the voltage stabalization time */
static inline void
count_off_vst(void)
{
udelay(vstable * VST_UNITS_20US);
return;
}
/* write the new fid value along with the other control fields to the msr */
static int
write_new_fid(u32 fid)
{
u32 lo;
u32 savevid = currvid;
if ((fid & INVALID_FID_MASK) || (currvid & INVALID_VID_MASK)) {
printk(KERN_ERR PFX "internal error - overflow on fid write\n");
return 1;
}
lo = fid | (currvid << MSR_C_LO_VID_SHIFT) | MSR_C_LO_INIT_FID_VID;
dprintk(KERN_DEBUG PFX "writing fid %x, lo %x, hi %x\n",
fid, lo, plllock * PLL_LOCK_CONVERSION);
wrmsr(MSR_FIDVID_CTL, lo, plllock * PLL_LOCK_CONVERSION);
if (query_current_values_with_pending_wait())
return 1;
count_off_irt();
if (savevid != currvid) {
printk(KERN_ERR PFX
"vid changed on fid transition, save %x, currvid %x\n",
savevid, currvid);
return 1;
}
if (fid != currfid) {
printk(KERN_ERR PFX
"fid transition failed, fid %x, currfid %x\n",
fid, currfid);
return 1;
}
return 0;
}
/* Write a new vid to the hardware */
static int
write_new_vid(u32 vid)
{
u32 lo;
u32 savefid = currfid;
if ((currfid & INVALID_FID_MASK) || (vid & INVALID_VID_MASK)) {
printk(KERN_ERR PFX "internal error - overflow on vid write\n");
return 1;
}
lo = currfid | (vid << MSR_C_LO_VID_SHIFT) | MSR_C_LO_INIT_FID_VID;
dprintk(KERN_DEBUG PFX "writing vid %x, lo %x, hi %x\n",
vid, lo, STOP_GRANT_5NS);
wrmsr(MSR_FIDVID_CTL, lo, STOP_GRANT_5NS);
if (query_current_values_with_pending_wait()) {
return 1;
}
if (savefid != currfid) {
printk(KERN_ERR PFX
"fid changed on vid transition, save %x currfid %x\n",
savefid, currfid);
return 1;
}
if (vid != currvid) {
printk(KERN_ERR PFX
"vid transition failed, vid %x, currvid %x\n",
vid, 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 0x1f is off.
*/
static int
decrease_vid_code_by_step(u32 reqvid, u32 step)
{
if ((currvid - reqvid) > step)
reqvid = currvid - step;
if (write_new_vid(reqvid))
return 1;
count_off_vst();
return 0;
}
/* Change the fid and vid, by the 3 phases. */
static inline int
transition_fid_vid(u32 reqfid, u32 reqvid)
{
if (core_voltage_pre_transition(reqvid))
return 1;
if (core_frequency_transition(reqfid))
return 1;
if (core_voltage_post_transition(reqvid))
return 1;
if (query_current_values_with_pending_wait())
return 1;
if ((reqfid != currfid) || (reqvid != currvid)) {
printk(KERN_ERR PFX "failed: req 0x%x 0x%x, curr 0x%x 0x%x\n",
reqfid, reqvid, currfid, currvid);
return 1;
}
dprintk(KERN_INFO PFX
"transitioned: new fid 0x%x, vid 0x%x\n", currfid, currvid);
return 0;
}
/*
* Phase 1 - core voltage transition ... setup appropriate voltage for the
* fid transition.
*/
static inline int
core_voltage_pre_transition(u32 reqvid)
{
u32 rvosteps = rvo;
u32 savefid = currfid;
dprintk(KERN_DEBUG PFX
"ph1: start, currfid 0x%x, currvid 0x%x, reqvid 0x%x, rvo %x\n",
currfid, currvid, reqvid, rvo);
while (currvid > reqvid) {
dprintk(KERN_DEBUG PFX "ph1: curr 0x%x, requesting vid 0x%x\n",
currvid, reqvid);
if (decrease_vid_code_by_step(reqvid, vidmvs))
return 1;
}
while (rvosteps > 0) {
if (currvid == 0) {
rvosteps = 0;
} else {
dprintk(KERN_DEBUG PFX
"ph1: changing vid for rvo, requesting 0x%x\n",
currvid - 1);
if (decrease_vid_code_by_step(currvid - 1, 1))
return 1;
rvosteps--;
}
}
if (query_current_values_with_pending_wait())
return 1;
if (savefid != currfid) {
printk(KERN_ERR PFX "ph1 err, currfid changed 0x%x\n", currfid);
return 1;
}
dprintk(KERN_DEBUG PFX "ph1 complete, currfid 0x%x, currvid 0x%x\n",
currfid, currvid);
return 0;
}
/* Phase 2 - core frequency transition */
static inline int
core_frequency_transition(u32 reqfid)
{
u32 vcoreqfid;
u32 vcocurrfid;
u32 vcofiddiff;
u32 savevid = currvid;
if ((reqfid < HI_FID_TABLE_BOTTOM) && (currfid < HI_FID_TABLE_BOTTOM)) {
printk(KERN_ERR PFX "ph2 illegal lo-lo transition 0x%x 0x%x\n",
reqfid, currfid);
return 1;
}
if (currfid == reqfid) {
printk(KERN_ERR PFX "ph2 null fid transition 0x%x\n", currfid);
return 0;
}
dprintk(KERN_DEBUG PFX
"ph2 starting, currfid 0x%x, currvid 0x%x, reqfid 0x%x\n",
currfid, currvid, reqfid);
vcoreqfid = convert_fid_to_vco_fid(reqfid);
vcocurrfid = convert_fid_to_vco_fid(currfid);
vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
: vcoreqfid - vcocurrfid;
while (vcofiddiff > 2) {
if (reqfid > currfid) {
if (currfid > LO_FID_TABLE_TOP) {
if (write_new_fid(currfid + 2)) {
return 1;
}
} else {
if (write_new_fid
(2 + convert_fid_to_vco_fid(currfid))) {
return 1;
}
}
} else {
if (write_new_fid(currfid - 2))
return 1;
}
vcocurrfid = convert_fid_to_vco_fid(currfid);
vcofiddiff = vcocurrfid > vcoreqfid ? vcocurrfid - vcoreqfid
: vcoreqfid - vcocurrfid;
}
if (write_new_fid(reqfid))
return 1;
if (query_current_values_with_pending_wait())
return 1;
if (currfid != reqfid) {
printk(KERN_ERR PFX
"ph2 mismatch, failed fid transition, curr %x, req %x\n",
currfid, reqfid);
return 1;
}
if (savevid != currvid) {
printk(KERN_ERR PFX
"ph2 vid changed, save %x, curr %x\n", savevid,
currvid);
return 1;
}
dprintk(KERN_DEBUG PFX "ph2 complete, currfid 0x%x, currvid 0x%x\n",
currfid, currvid);
return 0;
}
/* Phase 3 - core voltage transition flow ... jump to the final vid. */
static inline int
core_voltage_post_transition(u32 reqvid)
{
u32 savefid = currfid;
u32 savereqvid = reqvid;
dprintk(KERN_DEBUG PFX "ph3 starting, currfid 0x%x, currvid 0x%x\n",
currfid, currvid);
if (reqvid != currvid) {
if (write_new_vid(reqvid))
return 1;
if (savefid != currfid) {
printk(KERN_ERR PFX
"ph3: bad fid change, save %x, curr %x\n",
savefid, currfid);
return 1;
}
if (currvid != reqvid) {
printk(KERN_ERR PFX
"ph3: failed vid transition\n, req %x, curr %x",
reqvid, currvid);
return 1;
}
}
if (query_current_values_with_pending_wait())
return 1;
if (savereqvid != currvid) {
dprintk(KERN_ERR PFX "ph3 failed, currvid 0x%x\n", currvid);
return 1;
}
if (savefid != currfid) {
dprintk(KERN_ERR PFX "ph3 failed, currfid changed 0x%x\n",
currfid);
return 1;
}
dprintk(KERN_DEBUG PFX "ph3 complete, currfid 0x%x, currvid 0x%x\n",
currfid, currvid);
return 0;
}
static inline int
check_supported_cpu(void)
{
struct cpuinfo_x86 *c = cpu_data;
u32 eax, ebx, ecx, edx;
if (num_online_cpus() != 1) {
printk(KERN_INFO PFX "multiprocessor systems not supported\n");
return 0;
}
if (c->x86_vendor != X86_VENDOR_AMD) {
#ifdef MODULE
printk(KERN_INFO PFX "Not an AMD processor\n");
#endif
return 0;
}
eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
if ((eax & CPUID_XFAM_MOD) == ATHLON64_XFAM_MOD) {
dprintk(KERN_DEBUG PFX "AMD Althon 64 Processor found\n");
if ((eax & CPUID_F1_STEP) < ATHLON64_REV_C0) {
printk(KERN_INFO PFX "Revision C0 or better "
"AMD Athlon 64 processor required\n");
return 0;
}
} else if ((eax & CPUID_XFAM_MOD) == OPTERON_XFAM_MOD) {
dprintk(KERN_DEBUG PFX "AMD Opteron Processor found\n");
} else {
printk(KERN_INFO PFX
"AMD Athlon 64 or AMD Opteron processor required\n");
return 0;
}
eax = cpuid_eax(CPUID_GET_MAX_CAPABILITIES);
if (eax < CPUID_FREQ_VOLT_CAPABILITIES) {
printk(KERN_INFO PFX
"No frequency change capabilities detected\n");
return 0;
}
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");
return 0;
}
printk(KERN_INFO PFX "Found AMD64 processor supporting PowerNow (" VERSION ")\n");
return 1;
}
static int check_pst_table(struct pst_s *pst, u8 maxvid)
{
unsigned int j;
u8 lastfid = 0xFF;
for (j = 0; j < 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 < rvo) { /* vid + rvo >= 0 */
printk(KERN_ERR PFX
"BIOS error - 0 vid exceeded with pstate %d\n",
j);
return -ENODEV;
}
if (pst[j].vid < maxvid + rvo) { /* vid + rvo >= maxvid */
printk(KERN_ERR PFX
"BIOS error - maxvid exceeded with pstate %d\n",
j);
return -ENODEV;
}
if ((pst[j].fid > MAX_FID)
|| (pst[j].fid & 1)
|| (pst[j].fid < HI_FID_TABLE_BOTTOM)){
printk(KERN_ERR PFX "fid %d invalid : 0x%x\n", j, pst[j].fid);
return -EINVAL;
}
if (pst[j].fid < lastfid)
lastfid = pst[j].fid;
}
if (lastfid & 1) {
printk(KERN_ERR PFX "lastfid invalid\n");
return -EINVAL;
}
if (lastfid > LO_FID_TABLE_TOP) {
printk(KERN_INFO PFX "first fid not from lo freq table\n");
}
return 0;
}
/* Find and validate the PSB/PST table in BIOS. */
static inline int
find_psb_table(void)
{
struct psb_s *psb;
struct pst_s *pst;
unsigned int i, j;
u32 mvs;
u8 maxvid;
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(KERN_DEBUG PFX "found PSB header at 0x%p\n", psb);
dprintk(KERN_DEBUG PFX "table vers: 0x%x\n", psb->tableversion);
if (psb->tableversion != PSB_VERSION_1_4) {
printk(KERN_INFO BFX "PSB table is not v1.4\n");
return -ENODEV;
}
dprintk(KERN_DEBUG PFX "flags: 0x%x\n", psb->flags1);
if (psb->flags1) {
printk(KERN_ERR BFX "unknown flags\n");
return -ENODEV;
}
vstable = psb->voltagestabilizationtime;
dprintk(KERN_DEBUG PFX "flags2: 0x%x\n", psb->flags2);
rvo = psb->flags2 & 3;
irt = ((psb->flags2) >> 2) & 3;
mvs = ((psb->flags2) >> 4) & 3;
vidmvs = 1 << mvs;
batps = ((psb->flags2) >> 6) & 3;
printk(KERN_INFO PFX "voltage stable in %d usec", vstable * 20);
if (batps)
printk(", only %d lowest states on battery", batps);
printk(", ramp voltage offset: %d", rvo);
printk(", isochronous relief time: %d", irt);
printk(", maximum voltage step: %d\n", mvs);
dprintk(KERN_DEBUG PFX "numpst: 0x%x\n", psb->numpst);
if (psb->numpst != 1) {
printk(KERN_ERR BFX "numpst must be 1\n");
return -ENODEV;
}
dprintk(KERN_DEBUG PFX "cpuid: 0x%x\n", psb->cpuid);
plllock = psb->plllocktime;
printk(KERN_INFO PFX "pll lock time: 0x%x, ", plllock);
maxvid = psb->maxvid;
printk("maxfid 0x%x (%d MHz), maxvid 0x%x\n",
psb->maxfid, find_freq_from_fid(psb->maxfid), maxvid);
numps = psb->numpstates;
if (numps < 2) {
printk(KERN_ERR BFX "no p states to transition\n");
return -ENODEV;
}
if (batps == 0) {
batps = numps;
} else if (batps > numps) {
printk(KERN_ERR BFX "batterypstates > numpstates\n");
batps = numps;
} else {
printk(KERN_ERR PFX
"Restricting operation to %d p-states\n", batps);
printk(KERN_ERR PFX
"Check for an updated driver to access all "
"%d p-states\n", numps);
}
if (numps <= 1) {
printk(KERN_ERR PFX "only 1 p-state to transition\n");
return -ENODEV;
}
pst = (struct pst_s *) (psb + 1);
if (check_pst_table(pst, maxvid))
return -EINVAL;
powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table) * (numps + 1)), GFP_KERNEL);
if (!powernow_table) {
printk(KERN_ERR PFX "powernow_table memory alloc failure\n");
return -ENOMEM;
}
for (j = 0; j < numps; j++) {
printk(KERN_INFO PFX " %d : fid 0x%x (%d MHz), vid 0x%x\n", j,
pst[j].fid, find_freq_from_fid(pst[j].fid), pst[j].vid);
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_freq_from_fid(pst[j].fid);
}
powernow_table[numps].frequency = CPUFREQ_TABLE_END;
powernow_table[numps].index = 0;
if (query_current_values_with_pending_wait()) {
kfree(powernow_table);
return -EIO;
}
printk(KERN_INFO PFX "currfid 0x%x (%d MHz), currvid 0x%x\n",
currfid, find_freq_from_fid(currfid), currvid);
for (j = 0; j < numps; j++)
if ((pst[j].fid==currfid) && (pst[j].vid==currvid))
return 0;
printk(KERN_ERR BFX "currfid/vid do not match PST, ignoring\n");
return 0;
}
printk(KERN_ERR BFX "no PSB\n");
return -ENODEV;
}
/* Take a frequency, and issue the fid/vid transition command */
static inline int
transition_frequency(unsigned int index)
{
u32 fid;
u32 vid;
int res;
struct cpufreq_freqs freqs;
/* 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 = powernow_table[index].index & 0xFF;
vid = (powernow_table[index].index & 0xFF00) >> 8;
dprintk(KERN_DEBUG PFX "table matched fid 0x%x, giving vid 0x%x\n",
fid, vid);
if (query_current_values_with_pending_wait())
return 1;
if ((currvid == vid) && (currfid == fid)) {
dprintk(KERN_DEBUG PFX
"target matches current values (fid 0x%x, vid 0x%x)\n",
fid, vid);
return 0;
}
if ((fid < HI_FID_TABLE_BOTTOM) && (currfid < HI_FID_TABLE_BOTTOM)) {
printk(KERN_ERR PFX
"ignoring illegal change in lo freq table-%x to %x\n",
currfid, fid);
return 1;
}
dprintk(KERN_DEBUG PFX "changing to fid 0x%x, vid 0x%x\n", fid, vid);
freqs.cpu = 0; /* only true because SMP not supported */
freqs.old = find_freq_from_fid(currfid);
freqs.new = find_freq_from_fid(fid);
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
res = transition_fid_vid(fid, vid);
freqs.new = find_freq_from_fid(currfid);
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)
{
u32 checkfid = currfid;
u32 checkvid = currvid;
unsigned int newstate;
if (pending_bit_stuck()) {
printk(KERN_ERR PFX "drv targ fail: change pending bit set\n");
return -EIO;
}
dprintk(KERN_DEBUG PFX "targ: %d kHz, min %d, max %d, relation %d\n",
targfreq, pol->min, pol->max, relation);
if (query_current_values_with_pending_wait())
return -EIO;
dprintk(KERN_DEBUG PFX "targ: curr fid 0x%x, vid 0x%x\n",
currfid, currvid);
if ((checkvid != currvid) || (checkfid != currfid)) {
printk(KERN_ERR PFX
"error - out of sync, fid 0x%x 0x%x, vid 0x%x 0x%x\n",
checkfid, currfid, checkvid, currvid);
}
if (cpufreq_frequency_table_target(pol, powernow_table, targfreq, relation, &newstate))
return -EINVAL;
if (transition_frequency(newstate))
{
printk(KERN_ERR PFX "transition frequency failed\n");
return 1;
}
pol->cur = 1000 * find_freq_from_fid(currfid);
return 0;
}
/* Driver entry point to verify the policy and range of frequencies */
static int
powernowk8_verify(struct cpufreq_policy *pol)
{
if (pending_bit_stuck()) {
printk(KERN_ERR PFX "failing verify, change pending bit set\n");
return -EIO;
}
return cpufreq_frequency_table_verify(pol, powernow_table);
}
/* per CPU init entry point to the driver */
static int __init
powernowk8_cpu_init(struct cpufreq_policy *pol)
{
if (pol->cpu != 0) {
printk(KERN_ERR PFX "init not cpu 0\n");
return -ENODEV;
}
pol->governor = CPUFREQ_DEFAULT_GOVERNOR;
/* Take a crude guess here.
* That guess was in microseconds, so multply with 1000 */
pol->cpuinfo.transition_latency = (((rvo + 8) * vstable * VST_UNITS_20US)
+ (3 * (1 << irt) * 10)) * 1000;
if (query_current_values_with_pending_wait())
return -EIO;
pol->cur = 1000 * find_freq_from_fid(currfid);
dprintk(KERN_DEBUG PFX "policy current frequency %d kHz\n", pol->cur);
/* min/max the cpu is capable of */
if (cpufreq_frequency_table_cpuinfo(pol, powernow_table)) {
printk(KERN_ERR PFX "invalid powernow_table\n");
kfree(powernow_table);
return -EINVAL;
}
printk(KERN_INFO PFX "cpu_init done, current fid 0x%x, vid 0x%x\n",
currfid, currvid);
return 0;
}
static int __exit powernowk8_cpu_exit (struct cpufreq_policy *pol)
{
if (pol->cpu != 0)
return -EINVAL;
if (powernow_table)
kfree(powernow_table);
return 0;
}
static struct cpufreq_driver cpufreq_amd64_driver = {
.verify = powernowk8_verify,
.target = powernowk8_target,
.init = powernowk8_cpu_init,
.exit = powernowk8_cpu_exit,
.name = "powernow-k8",
.owner = THIS_MODULE,
};
/* driver entry point for init */
static int __init
powernowk8_init(void)
{
int rc;
if (check_supported_cpu() == 0)
return -ENODEV;
rc = find_psb_table();
if (rc)
return rc;
if (pending_bit_stuck()) {
printk(KERN_ERR PFX "powernowk8_init fail, change pending bit set\n");
return -EIO;
}
return cpufreq_register_driver(&cpufreq_amd64_driver);
}
/* driver entry point for term */
static void __exit
powernowk8_exit(void)
{
dprintk(KERN_INFO PFX "powernowk8_exit\n");
cpufreq_unregister_driver(&cpufreq_amd64_driver);
}
MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com>");
MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
MODULE_LICENSE("GPL");
module_init(powernowk8_init);
module_exit(powernowk8_exit);
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