[PATCH][try 5] architectural pstate driver for powernow-k8

From: Mark Langsdorf
Date: Wed Oct 17 2007 - 17:52:30 EST

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This patch should apply cleanly to the 2.6.23-git7 kernel. It changes the
powernow-k8 driver code that deals with 3rd generation Opteron, Phenom,
and later processors to match the architectural pstate driver described
in the AMD64 Architecture Programmer's Manual Volume 2 Chapter 18. The
initial implementation of the hardware pstate driver for PowerNow!
used some processor-version specific features, and would not be
maintainable in the long term as the processor features changed.
This architectural driver should work on all future AMD processors.

Signed-off-by: Mark Langsdorf <mark.langsdorf@xxxxxxx>
Signed-off-by: Andreas Herrmann <andreas.herrmann3@xxxxxxx>

diff -urpN -X linux-2.6.23-git7/Documentation/dontdiff linux-2.6.23-git7/arch/x86/kernel/cpu/cpufreq/powernow-k8.c linux-2.6.23-apn-git7/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
--- linux-2.6.23-git7/arch/x86/kernel/cpu/cpufreq/powernow-k8.c 2007-10-15 11:20:39.000000000 -0500
+++ linux-2.6.23-apn-git7/arch/x86/kernel/cpu/cpufreq/powernow-k8.c 2007-10-15 16:20:00.000000000 -0500
@@ -46,7 +46,7 @@

#define PFX "powernow-k8: "
#define BFX PFX "BIOS error: "
-#define VERSION "version 2.00.00"
+#define VERSION "version 2.20.00"
#include "powernow-k8.h"

/* serialize freq changes */
@@ -73,33 +73,11 @@ static u32 find_khz_freq_from_fid(u32 fi
return 1000 * find_freq_from_fid(fid);
}

-/* Return a frequency in MHz, given an input fid and did */
-static u32 find_freq_from_fiddid(u32 fid, u32 did)
+static u32 find_khz_freq_from_pstate(struct cpufreq_frequency_table *data, u32 pstate)
{
- if (current_cpu_data.x86 == 0x10)
- return 100 * (fid + 0x10) >> did;
- else
- return 100 * (fid + 0x8) >> did;
-}
-
-static u32 find_khz_freq_from_fiddid(u32 fid, u32 did)
-{
- return 1000 * find_freq_from_fiddid(fid, did);
-}
-
-static u32 find_fid_from_pstate(u32 pstate)
-{
- u32 hi, lo;
- rdmsr(MSR_PSTATE_DEF_BASE + pstate, lo, hi);
- return lo & HW_PSTATE_FID_MASK;
+ return data[pstate].frequency;
}

-static u32 find_did_from_pstate(u32 pstate)
-{
- u32 hi, lo;
- rdmsr(MSR_PSTATE_DEF_BASE + pstate, lo, hi);
- return (lo & HW_PSTATE_DID_MASK) >> HW_PSTATE_DID_SHIFT;
-}

/* Return the vco fid for an input fid
*
@@ -142,9 +120,7 @@ static int query_current_values_with_pen
if (cpu_family == CPU_HW_PSTATE) {
rdmsr(MSR_PSTATE_STATUS, lo, hi);
i = lo & HW_PSTATE_MASK;
- rdmsr(MSR_PSTATE_DEF_BASE + i, lo, hi);
- data->currfid = lo & HW_PSTATE_FID_MASK;
- data->currdid = (lo & HW_PSTATE_DID_MASK) >> HW_PSTATE_DID_SHIFT;
+ data->currpstate = i;
return 0;
}
do {
@@ -295,7 +271,7 @@ static int decrease_vid_code_by_step(str
static int transition_pstate(struct powernow_k8_data *data, u32 pstate)
{
wrmsr(MSR_PSTATE_CTRL, pstate, 0);
- data->currfid = find_fid_from_pstate(pstate);
+ data->currpstate = pstate;
return 0;
}

@@ -845,17 +821,20 @@ err_out:
static int fill_powernow_table_pstate(struct powernow_k8_data *data, struct cpufreq_frequency_table *powernow_table)
{
int i;
+ u32 hi = 0, lo = 0;
+ rdmsr(MSR_PSTATE_CUR_LIMIT, hi, lo);
+ data->max_hw_pstate = (hi & HW_PSTATE_MAX_MASK) >> HW_PSTATE_MAX_SHIFT;

for (i = 0; i < data->acpi_data.state_count; i++) {
u32 index;
u32 hi = 0, lo = 0;
- u32 fid;
- u32 did;

index = data->acpi_data.states[i].control & HW_PSTATE_MASK;
- if (index > MAX_HW_PSTATE) {
+ if (index > data->max_hw_pstate) {
printk(KERN_ERR PFX "invalid pstate %d - bad value %d.\n", i, index);
printk(KERN_ERR PFX "Please report to BIOS manufacturer\n");
+ powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
+ continue;
}
rdmsr(MSR_PSTATE_DEF_BASE + index, lo, hi);
if (!(hi & HW_PSTATE_VALID_MASK)) {
@@ -864,22 +843,9 @@ static int fill_powernow_table_pstate(st
continue;
}

- fid = lo & HW_PSTATE_FID_MASK;
- did = (lo & HW_PSTATE_DID_MASK) >> HW_PSTATE_DID_SHIFT;
+ powernow_table[i].index = index;

- dprintk(" %d : fid 0x%x, did 0x%x\n", index, fid, did);
-
- powernow_table[i].index = index | (fid << HW_FID_INDEX_SHIFT) | (did << HW_DID_INDEX_SHIFT);
-
- powernow_table[i].frequency = find_khz_freq_from_fiddid(fid, did);
-
- 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[i].frequency = data->acpi_data.states[i].core_frequency * 1000;
}
return 0;
}
@@ -1020,22 +986,18 @@ static int transition_frequency_fidvid(s
/* Take a frequency, and issue the hardware pstate transition command */
static int transition_frequency_pstate(struct powernow_k8_data *data, unsigned int index)
{
- u32 fid = 0;
- u32 did = 0;
u32 pstate = 0;
int res, i;
struct cpufreq_freqs freqs;

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

- /* get fid did for hardware pstate transition */
+ /* get MSR index for hardware pstate transition */
pstate = index & HW_PSTATE_MASK;
- if (pstate > MAX_HW_PSTATE)
+ if (pstate > data->max_hw_pstate)
return 0;
- fid = (index & HW_FID_INDEX_MASK) >> HW_FID_INDEX_SHIFT;
- did = (index & HW_DID_INDEX_MASK) >> HW_DID_INDEX_SHIFT;
- freqs.old = find_khz_freq_from_fiddid(data->currfid, data->currdid);
- freqs.new = find_khz_freq_from_fiddid(fid, did);
+ freqs.old = find_khz_freq_from_pstate(data->powernow_table, data->currpstate);
+ freqs.new = find_khz_freq_from_pstate(data->powernow_table, pstate);

for_each_cpu_mask(i, *(data->available_cores)) {
freqs.cpu = i;
@@ -1043,9 +1005,7 @@ static int transition_frequency_pstate(s
}

res = transition_pstate(data, pstate);
- data->currfid = find_fid_from_pstate(pstate);
- data->currdid = find_did_from_pstate(pstate);
- freqs.new = find_khz_freq_from_fiddid(data->currfid, data->currdid);
+ freqs.new = find_khz_freq_from_pstate(data->powernow_table, pstate);

for_each_cpu_mask(i, *(data->available_cores)) {
freqs.cpu = i;
@@ -1090,10 +1050,7 @@ static int powernowk8_target(struct cpuf
if (query_current_values_with_pending_wait(data))
goto err_out;

- if (cpu_family == CPU_HW_PSTATE)
- dprintk("targ: curr fid 0x%x, did 0x%x\n",
- data->currfid, data->currdid);
- else {
+ if (cpu_family != CPU_HW_PSTATE) {
dprintk("targ: curr fid 0x%x, vid 0x%x\n",
data->currfid, data->currvid);

@@ -1124,7 +1081,7 @@ static int powernowk8_target(struct cpuf
mutex_unlock(&fidvid_mutex);

if (cpu_family == CPU_HW_PSTATE)
- pol->cur = find_khz_freq_from_fiddid(data->currfid, data->currdid);
+ pol->cur = find_khz_freq_from_pstate(data->powernow_table, newstate);
else
pol->cur = find_khz_freq_from_fid(data->currfid);
ret = 0;
@@ -1223,7 +1180,7 @@ static int __cpuinit powernowk8_cpu_init
+ (3 * (1 << data->irt) * 10)) * 1000;

if (cpu_family == CPU_HW_PSTATE)
- pol->cur = find_khz_freq_from_fiddid(data->currfid, data->currdid);
+ pol->cur = find_khz_freq_from_pstate(data->powernow_table, data->currpstate);
else
pol->cur = find_khz_freq_from_fid(data->currfid);
dprintk("policy current frequency %d kHz\n", pol->cur);
@@ -1240,8 +1197,7 @@ static int __cpuinit powernowk8_cpu_init
cpufreq_frequency_table_get_attr(data->powernow_table, pol->cpu);

if (cpu_family == CPU_HW_PSTATE)
- dprintk("cpu_init done, current fid 0x%x, did 0x%x\n",
- data->currfid, data->currdid);
+ dprintk("cpu_init done, current pstate 0x%x\n", data->currpstate);
else
dprintk("cpu_init done, current fid 0x%x, vid 0x%x\n",
data->currfid, data->currvid);
@@ -1297,7 +1253,7 @@ static unsigned int powernowk8_get (unsi
goto out;

if (cpu_family == CPU_HW_PSTATE)
- khz = find_khz_freq_from_fiddid(data->currfid, data->currdid);
+ khz = find_khz_freq_from_pstate(data->powernow_table, data->currpstate);
else
khz = find_khz_freq_from_fid(data->currfid);

diff -urpN -X linux-2.6.23-git7/Documentation/dontdiff linux-2.6.23-git7/arch/x86/kernel/cpu/cpufreq/powernow-k8.h linux-2.6.23-apn-git7/arch/x86/kernel/cpu/cpufreq/powernow-k8.h
--- linux-2.6.23-git7/arch/x86/kernel/cpu/cpufreq/powernow-k8.h 2007-10-15 11:20:39.000000000 -0500
+++ linux-2.6.23-apn-git7/arch/x86/kernel/cpu/cpufreq/powernow-k8.h 2007-10-15 11:27:44.000000000 -0500
@@ -10,6 +10,7 @@ struct powernow_k8_data {

u32 numps; /* number of p-states */
u32 batps; /* number of p-states supported on battery */
+ u32 max_hw_pstate; /* maximum legal hardware pstate */

/* these values are constant when the PSB is used to determine
* vid/fid pairings, but are modified during the ->target() call
@@ -21,8 +22,8 @@ struct powernow_k8_data {
u32 plllock; /* pll lock time, units 1 us */
u32 exttype; /* extended interface = 1 */

- /* keep track of the current fid / vid or did */
- u32 currvid, currfid, currdid;
+ /* keep track of the current fid / vid or pstate */
+ u32 currvid, currfid, currpstate;

/* the powernow_table includes all frequency and vid/fid pairings:
* fid are the lower 8 bits of the index, vid are the upper 8 bits.
@@ -87,23 +88,14 @@ struct powernow_k8_data {

/* Hardware Pstate _PSS and MSR definitions */
#define USE_HW_PSTATE 0x00000080
-#define HW_PSTATE_FID_MASK 0x0000003f
-#define HW_PSTATE_DID_MASK 0x000001c0
-#define HW_PSTATE_DID_SHIFT 6
#define HW_PSTATE_MASK 0x00000007
#define HW_PSTATE_VALID_MASK 0x80000000
-#define HW_FID_INDEX_SHIFT 8
-#define HW_FID_INDEX_MASK 0x0000ff00
-#define HW_DID_INDEX_SHIFT 16
-#define HW_DID_INDEX_MASK 0x00ff0000
-#define HW_WATTS_MASK 0xff
-#define HW_PWR_DVR_MASK 0x300
-#define HW_PWR_DVR_SHIFT 8
-#define HW_PWR_MAX_MULT 3
-#define MAX_HW_PSTATE 8 /* hw pstate supports up to 8 */
+#define HW_PSTATE_MAX_MASK 0x000000f0
+#define HW_PSTATE_MAX_SHIFT 4
#define MSR_PSTATE_DEF_BASE 0xc0010064 /* base of Pstate MSRs */
#define MSR_PSTATE_STATUS 0xc0010063 /* Pstate Status MSR */
#define MSR_PSTATE_CTRL 0xc0010062 /* Pstate control MSR */
+#define MSR_PSTATE_CUR_LIMIT 0xc0010061 /* pstate current limit MSR */

/* define the two driver architectures */
#define CPU_OPTERON 0

-
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Next message: Charles Hardin: "[PATCH] pfkey: sending an SADB_GET responds with an SADB_GET"
Previous message: Christian Borntraeger: "Re: [PATCH] rd: Mark ramdisk buffers heads dirty"
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