diff options
Diffstat (limited to 'arch/x86/kernel/cpu/cpufreq/speedstep-lib.c')
| -rw-r--r-- | arch/x86/kernel/cpu/cpufreq/speedstep-lib.c | 34 |
1 files changed, 20 insertions, 14 deletions
diff --git a/arch/x86/kernel/cpu/cpufreq/speedstep-lib.c b/arch/x86/kernel/cpu/cpufreq/speedstep-lib.c index 55c696daa05c..2e3c6862657b 100644 --- a/arch/x86/kernel/cpu/cpufreq/speedstep-lib.c +++ b/arch/x86/kernel/cpu/cpufreq/speedstep-lib.c @@ -16,6 +16,7 @@ #include <linux/slab.h> #include <asm/msr.h> +#include <asm/tsc.h> #include "speedstep-lib.h" #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \ @@ -178,6 +179,15 @@ static unsigned int pentium4_get_frequency(void) u32 msr_lo, msr_hi, mult; unsigned int fsb = 0; unsigned int ret; + u8 fsb_code; + + /* Pentium 4 Model 0 and 1 do not have the Core Clock Frequency + * to System Bus Frequency Ratio Field in the Processor Frequency + * Configuration Register of the MSR. Therefore the current + * frequency cannot be calculated and has to be measured. + */ + if (c->x86_model < 2) + return cpu_khz; rdmsr(0x2c, msr_lo, msr_hi); @@ -188,21 +198,17 @@ static unsigned int pentium4_get_frequency(void) * 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_code = (msr_lo >> 16) & 0x7; + switch (fsb_code) { + case 0: 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; - } + break; + case 1: + fsb = 13333 * 10; + break; + case 2: + fsb = 200 * 1000; + break; } if (!fsb) |
