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Diffstat (limited to 'arch/i386/kernel/cpu/cpufreq/longhaul.c')
-rw-r--r--arch/i386/kernel/cpu/cpufreq/longhaul.c53
1 files changed, 31 insertions, 22 deletions
diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
index fa5cac255c16..b59878a0d9b3 100644
--- a/arch/i386/kernel/cpu/cpufreq/longhaul.c
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -8,12 +8,11 @@
* VIA have currently 3 different versions of Longhaul.
* Version 1 (Longhaul) uses the BCR2 MSR at 0x1147.
* It is present only in Samuel 1 (C5A), Samuel 2 (C5B) stepping 0.
- * Version 2 of longhaul is the same as v1, but adds voltage scaling.
- * Present in Samuel 2 (steppings 1-7 only) (C5B), and Ezra (C5C)
- * voltage scaling support has currently been disabled in this driver
- * until we have code that gets it right.
+ * Version 2 of longhaul is backward compatible with v1, but adds
+ * LONGHAUL MSR for purpose of both frequency and voltage scaling.
+ * Present in Samuel 2 (steppings 1-7 only) (C5B), and Ezra (C5C).
* Version 3 of longhaul got renamed to Powersaver and redesigned
- * to use the POWERSAVER MSR at 0x110a.
+ * to use only the POWERSAVER MSR at 0x110a.
* It is present in Ezra-T (C5M), Nehemiah (C5X) and above.
* It's pretty much the same feature wise to longhaul v2, though
* there is provision for scaling FSB too, but this doesn't work
@@ -298,26 +297,19 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
/*
* Longhaul v1. (Samuel[C5A] and Samuel2 stepping 0[C5B])
* Software controlled multipliers only.
- *
- * *NB* Until we get voltage scaling working v1 & v2 are the same code.
- * Longhaul v2 appears in Samuel2 Steppings 1->7 [C5b] and Ezra [C5C]
*/
case TYPE_LONGHAUL_V1:
- case TYPE_LONGHAUL_V2:
do_longhaul1(clock_ratio_index);
break;
/*
+ * Longhaul v2 appears in Samuel2 Steppings 1->7 [C5B] and Ezra [C5C]
+ *
* Longhaul v3 (aka Powersaver). (Ezra-T [C5M] & Nehemiah [C5N])
- * We can scale voltage with this too, but that's currently
- * disabled until we come up with a decent 'match freq to voltage'
- * algorithm.
- * When we add voltage scaling, we will also need to do the
- * voltage/freq setting in order depending on the direction
- * of scaling (like we do in powernow-k7.c)
* Nehemiah can do FSB scaling too, but this has never been proven
* to work in practice.
*/
+ case TYPE_LONGHAUL_V2:
case TYPE_POWERSAVER:
if (longhaul_flags & USE_ACPI_C3) {
/* Don't allow wakeup */
@@ -342,6 +334,7 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
local_irq_restore(flags);
preempt_enable();
+ freqs.new = calc_speed(longhaul_get_cpu_mult());
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
}
@@ -471,6 +464,8 @@ static void __init longhaul_setup_voltagescaling(void)
mV_vrm_table = &mV_vrm85[0];
} else {
printk (KERN_INFO PFX "Mobile VRM\n");
+ if (cpu_model < CPU_NEHEMIAH)
+ return;
vrm_mV_table = &mobilevrm_mV[0];
mV_vrm_table = &mV_mobilevrm[0];
}
@@ -656,6 +651,7 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
struct cpuinfo_x86 *c = cpu_data;
char *cpuname=NULL;
int ret;
+ u32 lo, hi;
int vt8235_present;
/* Check what we have on this motherboard */
@@ -669,16 +665,20 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
break;
case 7:
- longhaul_version = TYPE_LONGHAUL_V1;
switch (c->x86_mask) {
case 0:
+ longhaul_version = TYPE_LONGHAUL_V1;
cpu_model = CPU_SAMUEL2;
cpuname = "C3 'Samuel 2' [C5B]";
- /* Note, this is not a typo, early Samuel2's had Samuel1 ratios. */
- memcpy (clock_ratio, samuel1_clock_ratio, sizeof(samuel1_clock_ratio));
- memcpy (eblcr_table, samuel2_eblcr, sizeof(samuel2_eblcr));
+ /* Note, this is not a typo, early Samuel2's had
+ * Samuel1 ratios. */
+ memcpy(clock_ratio, samuel1_clock_ratio,
+ sizeof(samuel1_clock_ratio));
+ memcpy(eblcr_table, samuel2_eblcr,
+ sizeof(samuel2_eblcr));
break;
case 1 ... 15:
+ longhaul_version = TYPE_LONGHAUL_V2;
if (c->x86_mask < 8) {
cpu_model = CPU_SAMUEL2;
cpuname = "C3 'Samuel 2' [C5B]";
@@ -686,8 +686,10 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
cpu_model = CPU_EZRA;
cpuname = "C3 'Ezra' [C5C]";
}
- memcpy (clock_ratio, ezra_clock_ratio, sizeof(ezra_clock_ratio));
- memcpy (eblcr_table, ezra_eblcr, sizeof(ezra_eblcr));
+ memcpy(clock_ratio, ezra_clock_ratio,
+ sizeof(ezra_clock_ratio));
+ memcpy(eblcr_table, ezra_eblcr,
+ sizeof(ezra_eblcr));
break;
}
break;
@@ -728,6 +730,13 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
cpuname = "Unknown";
break;
}
+ /* Check Longhaul ver. 2 */
+ if (longhaul_version == TYPE_LONGHAUL_V2) {
+ rdmsr(MSR_VIA_LONGHAUL, lo, hi);
+ if (lo == 0 && hi == 0)
+ /* Looks like MSR isn't present */
+ longhaul_version = TYPE_LONGHAUL_V1;
+ }
printk (KERN_INFO PFX "VIA %s CPU detected. ", cpuname);
switch (longhaul_version) {
@@ -749,7 +758,7 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
NULL, (void *)&pr);
/* Check ACPI support for C3 state */
- if (pr != NULL && longhaul_version == TYPE_POWERSAVER) {
+ if (pr != NULL && longhaul_version != TYPE_LONGHAUL_V1) {
cx = &pr->power.states[ACPI_STATE_C3];
if (cx->address > 0 && cx->latency <= 1000) {
longhaul_flags |= USE_ACPI_C3;
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