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authorRussell King <rmk+kernel@arm.linux.org.uk>2014-03-19 20:15:46 +0000
committerRussell King <rmk+kernel@arm.linux.org.uk>2014-03-19 20:15:46 +0000
commit566b60c04ab230b8cc3845f964306f99504b18df (patch)
tree1897a526488c3496f4ffe5eebb39a1dd41ab731d /arch/x86/kernel/tsc_msr.c
parent3ba4cea21901d90d703b52e4a806fbafa86037a6 (diff)
parentc7edc9e326d53ca5ef9bed82de0740c6b107d55b (diff)
Merge branch 'uprobes-v7' of git://git.linaro.org/people/dave.long/linux into devel-stable
This patch series adds basic uprobes support to ARM. It is based on patches developed earlier by Rabin Vincent. That approach of adding hooks into the kprobes instruction parsing code was not well received. This approach separates the ARM instruction parsing code in kprobes out into a separate set of functions which can be used by both kprobes and uprobes. Both kprobes and uprobes then provide their own semantic action tables to process the results of the parsing.
Diffstat (limited to 'arch/x86/kernel/tsc_msr.c')
-rw-r--r--arch/x86/kernel/tsc_msr.c30
1 files changed, 15 insertions, 15 deletions
diff --git a/arch/x86/kernel/tsc_msr.c b/arch/x86/kernel/tsc_msr.c
index 8b5434f4389f..92ae6acac8a7 100644
--- a/arch/x86/kernel/tsc_msr.c
+++ b/arch/x86/kernel/tsc_msr.c
@@ -53,7 +53,7 @@ static struct freq_desc freq_desc_tables[] = {
/* TNG */
{ 6, 0x4a, 1, { 0, FREQ_100, FREQ_133, 0, 0, 0, 0, 0 } },
/* VLV2 */
- { 6, 0x37, 1, { 0, FREQ_100, FREQ_133, FREQ_166, 0, 0, 0, 0 } },
+ { 6, 0x37, 1, { FREQ_83, FREQ_100, FREQ_133, FREQ_166, 0, 0, 0, 0 } },
/* ANN */
{ 6, 0x5a, 1, { FREQ_83, FREQ_100, FREQ_133, FREQ_100, 0, 0, 0, 0 } },
};
@@ -77,21 +77,18 @@ static int match_cpu(u8 family, u8 model)
/*
* Do MSR calibration only for known/supported CPUs.
- * Return values:
- * -1: CPU is unknown/unsupported for MSR based calibration
- * 0: CPU is known/supported, but calibration failed
- * 1: CPU is known/supported, and calibration succeeded
+ *
+ * Returns the calibration value or 0 if MSR calibration failed.
*/
-int try_msr_calibrate_tsc(unsigned long *fast_calibrate)
+unsigned long try_msr_calibrate_tsc(void)
{
- int cpu_index;
u32 lo, hi, ratio, freq_id, freq;
+ unsigned long res;
+ int cpu_index;
cpu_index = match_cpu(boot_cpu_data.x86, boot_cpu_data.x86_model);
if (cpu_index < 0)
- return -1;
-
- *fast_calibrate = 0;
+ return 0;
if (freq_desc_tables[cpu_index].msr_plat) {
rdmsr(MSR_PLATFORM_INFO, lo, hi);
@@ -103,7 +100,7 @@ int try_msr_calibrate_tsc(unsigned long *fast_calibrate)
pr_info("Maximum core-clock to bus-clock ratio: 0x%x\n", ratio);
if (!ratio)
- return 0;
+ goto fail;
/* Get FSB FREQ ID */
rdmsr(MSR_FSB_FREQ, lo, hi);
@@ -112,16 +109,19 @@ int try_msr_calibrate_tsc(unsigned long *fast_calibrate)
pr_info("Resolved frequency ID: %u, frequency: %u KHz\n",
freq_id, freq);
if (!freq)
- return 0;
+ goto fail;
/* TSC frequency = maximum resolved freq * maximum resolved bus ratio */
- *fast_calibrate = freq * ratio;
- pr_info("TSC runs at %lu KHz\n", *fast_calibrate);
+ res = freq * ratio;
+ pr_info("TSC runs at %lu KHz\n", res);
#ifdef CONFIG_X86_LOCAL_APIC
lapic_timer_frequency = (freq * 1000) / HZ;
pr_info("lapic_timer_frequency = %d\n", lapic_timer_frequency);
#endif
+ return res;
- return 1;
+fail:
+ pr_warn("Fast TSC calibration using MSR failed\n");
+ return 0;
}