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;