[CPUFREQ] Longhaul - Add voltage scaling to driver
Rename option "dont_scale_voltage" to "scale_voltage" because
don't will be default.
Use "pos" for calculating voltage. In this way driver don't need
to know mV value or low level value. Simply min U is one pos and
max U is second pos. All pos between these two are used.
Assume that min U is for min f and max U for max f. For frequency
between min and max calculate pos based on difference between
current frequency and min f.
Values in mobile VRM table changed to values from
C3-M datasheet.
Signed-off-by: Rafa³ Bilski <rafalbilski@interia.pl>
Signed-off-by: Dave Jones <davej@redhat.com>
diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
index 43bbf948..f5cc9f5 100644
--- a/arch/i386/kernel/cpu/cpufreq/longhaul.c
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -53,19 +53,26 @@
#define CPU_NEHEMIAH 5
static int cpu_model;
-static unsigned int numscales=16, numvscales;
+static unsigned int numscales=16;
static unsigned int fsb;
-static int minvid, maxvid;
+
+static struct mV_pos *vrm_mV_table;
+static unsigned char *mV_vrm_table;
+struct f_msr {
+ unsigned char vrm;
+};
+static struct f_msr f_msr_table[32];
+
+static unsigned int highest_speed, lowest_speed; /* kHz */
static unsigned int minmult, maxmult;
static int can_scale_voltage;
-static int vrmrev;
static struct acpi_processor *pr = NULL;
static struct acpi_processor_cx *cx = NULL;
-static int port22_en = 0;
+static int port22_en;
/* Module parameters */
-static int dont_scale_voltage;
-static int ignore_latency = 0;
+static int scale_voltage;
+static int ignore_latency;
#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "longhaul", msg)
@@ -73,7 +80,6 @@
/* Clock ratios multiplied by 10 */
static int clock_ratio[32];
static int eblcr_table[32];
-static int voltage_table[32];
static unsigned int highest_speed, lowest_speed; /* kHz */
static int longhaul_version;
static struct cpufreq_frequency_table *longhaul_table;
@@ -163,6 +169,11 @@
longhaul.bits.SoftBusRatio4 = (clock_ratio_index & 0x10) >> 4;
longhaul.bits.EnableSoftBusRatio = 1;
+ if (can_scale_voltage) {
+ longhaul.bits.SoftVID = f_msr_table[clock_ratio_index].vrm;
+ longhaul.bits.EnableSoftVID = 1;
+ }
+
/* Sync to timer tick */
safe_halt();
/* Change frequency on next halt or sleep */
@@ -454,53 +465,57 @@
static void __init longhaul_setup_voltagescaling(void)
{
union msr_longhaul longhaul;
+ struct mV_pos minvid, maxvid;
+ unsigned int j, speed, pos, kHz_step, numvscales;
- rdmsrl (MSR_VIA_LONGHAUL, longhaul.val);
-
- if (!(longhaul.bits.RevisionID & 1))
+ rdmsrl(MSR_VIA_LONGHAUL, longhaul.val);
+ if (!(longhaul.bits.RevisionID & 1)) {
+ printk(KERN_INFO PFX "Voltage scaling not supported by CPU.\n");
return;
+ }
- minvid = longhaul.bits.MinimumVID;
- maxvid = longhaul.bits.MaximumVID;
- vrmrev = longhaul.bits.VRMRev;
+ if (!longhaul.bits.VRMRev) {
+ printk (KERN_INFO PFX "VRM 8.5\n");
+ vrm_mV_table = &vrm85_mV[0];
+ mV_vrm_table = &mV_vrm85[0];
+ } else {
+ printk (KERN_INFO PFX "Mobile VRM\n");
+ vrm_mV_table = &mobilevrm_mV[0];
+ mV_vrm_table = &mV_mobilevrm[0];
+ }
- if (minvid == 0 || maxvid == 0) {
+ minvid = vrm_mV_table[longhaul.bits.MinimumVID];
+ maxvid = vrm_mV_table[longhaul.bits.MaximumVID];
+ numvscales = maxvid.pos - minvid.pos + 1;
+ kHz_step = (highest_speed - lowest_speed) / numvscales;
+
+ if (minvid.mV == 0 || maxvid.mV == 0 || minvid.mV > maxvid.mV) {
printk (KERN_INFO PFX "Bogus values Min:%d.%03d Max:%d.%03d. "
"Voltage scaling disabled.\n",
- minvid/1000, minvid%1000, maxvid/1000, maxvid%1000);
+ minvid.mV/1000, minvid.mV%1000, maxvid.mV/1000, maxvid.mV%1000);
return;
}
- if (minvid == maxvid) {
+ if (minvid.mV == maxvid.mV) {
printk (KERN_INFO PFX "Claims to support voltage scaling but min & max are "
"both %d.%03d. Voltage scaling disabled\n",
- maxvid/1000, maxvid%1000);
+ maxvid.mV/1000, maxvid.mV%1000);
return;
}
- if (vrmrev==0) {
- dprintk ("VRM 8.5\n");
- memcpy (voltage_table, vrm85scales, sizeof(voltage_table));
- numvscales = (voltage_table[maxvid]-voltage_table[minvid])/25;
- } else {
- dprintk ("Mobile VRM\n");
- memcpy (voltage_table, mobilevrmscales, sizeof(voltage_table));
- numvscales = (voltage_table[maxvid]-voltage_table[minvid])/5;
+ printk(KERN_INFO PFX "Max VID=%d.%03d Min VID=%d.%03d, %d possible voltage scales\n",
+ maxvid.mV/1000, maxvid.mV%1000,
+ minvid.mV/1000, minvid.mV%1000,
+ numvscales);
+
+ j = 0;
+ while (longhaul_table[j].frequency != CPUFREQ_TABLE_END) {
+ speed = longhaul_table[j].frequency;
+ pos = (speed - lowest_speed) / kHz_step + minvid.pos;
+ f_msr_table[longhaul_table[j].index].vrm = mV_vrm_table[pos];
+ j++;
}
- /* Current voltage isn't readable at first, so we need to
- set it to a known value. The spec says to use maxvid */
- longhaul.bits.RevisionKey = longhaul.bits.RevisionID; /* FIXME: This is bad. */
- longhaul.bits.EnableSoftVID = 1;
- longhaul.bits.SoftVID = maxvid;
- wrmsrl (MSR_VIA_LONGHAUL, longhaul.val);
-
- minvid = voltage_table[minvid];
- maxvid = voltage_table[maxvid];
-
- dprintk ("Min VID=%d.%03d Max VID=%d.%03d, %d possible voltage scales\n",
- maxvid/1000, maxvid%1000, minvid/1000, minvid%1000, numvscales);
-
can_scale_voltage = 1;
}
@@ -685,7 +700,7 @@
return ret;
if ((longhaul_version==TYPE_LONGHAUL_V2 || longhaul_version==TYPE_POWERSAVER) &&
- (dont_scale_voltage==0))
+ (scale_voltage != 0))
longhaul_setup_voltagescaling();
policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
@@ -773,8 +788,8 @@
kfree(longhaul_table);
}
-module_param (dont_scale_voltage, int, 0644);
-MODULE_PARM_DESC(dont_scale_voltage, "Don't scale voltage of processor");
+module_param (scale_voltage, int, 0644);
+MODULE_PARM_DESC(scale_voltage, "Scale voltage of processor");
module_param(ignore_latency, int, 0644);
MODULE_PARM_DESC(ignore_latency, "Skip ACPI C3 latency test");