[PATCH 3.13 106/212] intel_pstate: Set turbo VID for BayTrail

From: Kamal Mostafa
Date: Tue Jun 17 2014 - 18:40:05 EST


3.13.11.4 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Dirk Brandewie <dirk.j.brandewie@xxxxxxxxx>

commit 21855ff5bcbdd075e1c99772827a84912ab083dd upstream.

A documentation update exposed that there is a separate set of VID
values that must be used in the turbo/boost P state range. Add
enumerating and setting the correct VID for P states in the turbo
range.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@xxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/cpufreq/intel_pstate.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index b687df8..bbfb81f 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -37,6 +37,7 @@
#define BYT_RATIOS 0x66a
#define BYT_VIDS 0x66b
#define BYT_TURBO_RATIOS 0x66c
+#define BYT_TURBO_VIDS 0x66d


#define FRAC_BITS 8
@@ -68,8 +69,9 @@ struct pstate_data {
};

struct vid_data {
- int32_t min;
- int32_t max;
+ int min;
+ int max;
+ int turbo;
int32_t ratio;
};

@@ -359,14 +361,14 @@ static int byt_get_min_pstate(void)
{
u64 value;
rdmsrl(BYT_RATIOS, value);
- return (value >> 8) & 0xFF;
+ return (value >> 8) & 0x3F;
}

static int byt_get_max_pstate(void)
{
u64 value;
rdmsrl(BYT_RATIOS, value);
- return (value >> 16) & 0xFF;
+ return (value >> 16) & 0x3F;
}

static int byt_get_turbo_pstate(void)
@@ -393,6 +395,9 @@ static void byt_set_pstate(struct cpudata *cpudata, int pstate)
vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
vid = fp_toint(vid_fp);

+ if (pstate > cpudata->pstate.max_pstate)
+ vid = cpudata->vid.turbo;
+
val |= vid;

wrmsrl(MSR_IA32_PERF_CTL, val);
@@ -402,13 +407,17 @@ static void byt_get_vid(struct cpudata *cpudata)
{
u64 value;

+
rdmsrl(BYT_VIDS, value);
- cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
- cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
+ cpudata->vid.min = int_tofp((value >> 8) & 0x3f);
+ cpudata->vid.max = int_tofp((value >> 16) & 0x3f);
cpudata->vid.ratio = div_fp(
cpudata->vid.max - cpudata->vid.min,
int_tofp(cpudata->pstate.max_pstate -
cpudata->pstate.min_pstate));
+
+ rdmsrl(BYT_TURBO_VIDS, value);
+ cpudata->vid.turbo = value & 0x7f;
}


--
1.9.1

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