[CPUFREQ] Support for 533 MHz FSB in speedstep driver.

diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c b/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
index e3a75684f1d13f99328fc2df0060cb171692c0fc..927d3bebd6ff57dbd9ab155fd863ba7016435779 100644 (file)
--- a/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
+++ b/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
@@ -106,14 +106,45 @@ static unsigned int pentium3_get_frequency (unsigned int processor)
 
 static unsigned int pentium4_get_frequency(void)
 {
-       u32 msr_lo, msr_hi;
+       struct cpuinfo_x86 *c = &boot_cpu_data;
+       u32 msr_lo, msr_hi, mult;
+       unsigned int fsb = 0;
 
        rdmsr(0x2c, msr_lo, msr_hi);
 
        dprintk(KERN_DEBUG "speedstep-lib: P4 - MSR_EBC_FREQUENCY_ID: 0x%x 0x%x\n", msr_lo, msr_hi);
 
-       msr_lo >>= 24;
-       return (msr_lo * 100000);
+       /* decode the FSB: see IA-32 Intel (C) Architecture Software 
+        * Developer's Manual, Volume 3: System Prgramming Guide,
+        * revision #12 in Table B-1: MSRs in the Pentium 4 and
+        * Intel Xeon Processors, on page B-4 and B-5.
+        */
+       if (c->x86_model < 2)
+               fsb = 100 * 1000;
+       else {
+               u8 fsb_code = (msr_lo >> 16) & 0x7;
+               switch (fsb_code) {
+               case 0:
+                       fsb = 100 * 1000;
+                       break;
+               case 1:
+                       fsb = 13333 * 10;
+                       break;
+               case 2:
+                       fsb = 200 * 1000;
+                       break;
+               }
+       }
+
+       if (!fsb)
+               printk(KERN_DEBUG "speedstep-lib: couldn't detect FSB speed. Please send an e-mail to <linux@brodo.de>\n");
+
+       /* Multiplier. */
+       mult = msr_lo >> 24;
+
+       dprintk(KERN_DEBUG "speedstep-lib: P4 - FSB %u kHz; Multiplier %u\n", fsb, mult);
+
+       return (fsb * mult);
 }
 
  

diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-lib.h b/arch/i386/kernel/cpu/cpufreq/speedstep-lib.h
index 04951e0e65d17f53da1a4508ab2d8fc994010485..ff7521d0195d62fcc83f95af385492a5199275ff 100644 (file)
--- a/arch/i386/kernel/cpu/cpufreq/speedstep-lib.h
+++ b/arch/i386/kernel/cpu/cpufreq/speedstep-lib.h
@@ -15,7 +15,7 @@
 #define SPEEDSTEP_PROCESSOR_PIII_C_EARLY       0x00000001  /* Coppermine core */
 #define SPEEDSTEP_PROCESSOR_PIII_C             0x00000002  /* Coppermine core */
 #define SPEEDSTEP_PROCESSOR_PIII_T             0x00000003  /* Tualatin core */
-#define SPEEDSTEP_PROCESSOR_P4M                        0x00000004  /* P4-M with 100 MHz FSB */
+#define SPEEDSTEP_PROCESSOR_P4M                        0x00000004  /* P4-M  */
 
 /* speedstep states -- only two of them */