[CPUFREQ] p4-clockmod: add more CPUs

Several more Intel CPUs are now capable using the p4-clockmod cpufreq
driver. As it is of limited use most of the time, print a big bold warning
if a better cpufreq driver might be available.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Dave Jones <davej@redhat.com>

1 files changed, 32 insertions, 0 deletions

diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c b/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
index 4f46cac155c4..6623a564f6fd 100644
--- a/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
+++ b/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
@@ -123,6 +123,36 @@ static unsigned int pentiumM_get_frequency(void)
         return (msr_tmp * 100 * 1000);
 }
 
+static unsigned int pentium_core_get_frequency(void)
+{
+        u32 fsb = 0;
+        u32 msr_lo, msr_tmp;
+
+        rdmsr(MSR_FSB_FREQ, msr_lo, msr_tmp);
+        /* see table B-2 of 24547212.pdf */
+        switch (msr_lo & 0x07) {
+        case 5:
+                fsb = 400;
+                break;
+        case 1:
+                fsb = 533;
+                break;
+        case 3:
+                fsb = 667;
+                break;
+        default:
+                printk(KERN_ERR "PCORE - MSR_FSB_FREQ undefined value");
+        }
+
+        rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_tmp);
+        dprintk("PCORE - MSR_IA32_EBL_CR_POWERON: 0x%x 0x%x\n", msr_lo, msr_tmp);
+
+        msr_tmp = (msr_lo >> 22) & 0x1f;
+        dprintk("bits 22-26 are 0x%x, speed is %u\n", msr_tmp, (msr_tmp * fsb * 1000));
+
+        return (msr_tmp * fsb * 1000);
+}
+
 
 static unsigned int pentium4_get_frequency(void)
 {
@@ -174,6 +204,8 @@ static unsigned int pentium4_get_frequency(void)
 unsigned int speedstep_get_processor_frequency(unsigned int processor)
 {
         switch (processor) {
+        case SPEEDSTEP_PROCESSOR_PCORE:
+                return pentium_core_get_frequency();
         case SPEEDSTEP_PROCESSOR_PM:
                 return pentiumM_get_frequency();
         case SPEEDSTEP_PROCESSOR_P4D: