diff options
Diffstat (limited to 'arch/x86_64')
-rw-r--r-- | arch/x86_64/kernel/apic.c | 2 | ||||
-rw-r--r-- | arch/x86_64/kernel/time.c | 58 | ||||
-rw-r--r-- | arch/x86_64/kernel/tsc.c | 12 | ||||
-rw-r--r-- | arch/x86_64/kernel/tsc_sync.c | 2 |
4 files changed, 64 insertions, 10 deletions
diff --git a/arch/x86_64/kernel/apic.c b/arch/x86_64/kernel/apic.c index bd3e45d47c37..3421f21b6c70 100644 --- a/arch/x86_64/kernel/apic.c +++ b/arch/x86_64/kernel/apic.c | |||
@@ -843,7 +843,7 @@ static int __init calibrate_APIC_clock(void) | |||
843 | } while ((tsc - tsc_start) < TICK_COUNT && | 843 | } while ((tsc - tsc_start) < TICK_COUNT && |
844 | (apic - apic_start) < TICK_COUNT); | 844 | (apic - apic_start) < TICK_COUNT); |
845 | 845 | ||
846 | result = (apic_start - apic) * 1000L * cpu_khz / | 846 | result = (apic_start - apic) * 1000L * tsc_khz / |
847 | (tsc - tsc_start); | 847 | (tsc - tsc_start); |
848 | } | 848 | } |
849 | printk("result %d\n", result); | 849 | printk("result %d\n", result); |
diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c index 811b8f987b50..5f862e216a42 100644 --- a/arch/x86_64/kernel/time.c +++ b/arch/x86_64/kernel/time.c | |||
@@ -43,6 +43,7 @@ | |||
43 | #include <asm/apic.h> | 43 | #include <asm/apic.h> |
44 | #include <asm/hpet.h> | 44 | #include <asm/hpet.h> |
45 | #include <asm/mpspec.h> | 45 | #include <asm/mpspec.h> |
46 | #include <asm/nmi.h> | ||
46 | 47 | ||
47 | static char *timename = NULL; | 48 | static char *timename = NULL; |
48 | 49 | ||
@@ -249,6 +250,51 @@ static unsigned long get_cmos_time(void) | |||
249 | return mktime(year, mon, day, hour, min, sec); | 250 | return mktime(year, mon, day, hour, min, sec); |
250 | } | 251 | } |
251 | 252 | ||
253 | /* calibrate_cpu is used on systems with fixed rate TSCs to determine | ||
254 | * processor frequency */ | ||
255 | #define TICK_COUNT 100000000 | ||
256 | static unsigned int __init tsc_calibrate_cpu_khz(void) | ||
257 | { | ||
258 | int tsc_start, tsc_now; | ||
259 | int i, no_ctr_free; | ||
260 | unsigned long evntsel3 = 0, pmc3 = 0, pmc_now = 0; | ||
261 | unsigned long flags; | ||
262 | |||
263 | for (i = 0; i < 4; i++) | ||
264 | if (avail_to_resrv_perfctr_nmi_bit(i)) | ||
265 | break; | ||
266 | no_ctr_free = (i == 4); | ||
267 | if (no_ctr_free) { | ||
268 | i = 3; | ||
269 | rdmsrl(MSR_K7_EVNTSEL3, evntsel3); | ||
270 | wrmsrl(MSR_K7_EVNTSEL3, 0); | ||
271 | rdmsrl(MSR_K7_PERFCTR3, pmc3); | ||
272 | } else { | ||
273 | reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i); | ||
274 | reserve_evntsel_nmi(MSR_K7_EVNTSEL0 + i); | ||
275 | } | ||
276 | local_irq_save(flags); | ||
277 | /* start meauring cycles, incrementing from 0 */ | ||
278 | wrmsrl(MSR_K7_PERFCTR0 + i, 0); | ||
279 | wrmsrl(MSR_K7_EVNTSEL0 + i, 1 << 22 | 3 << 16 | 0x76); | ||
280 | rdtscl(tsc_start); | ||
281 | do { | ||
282 | rdmsrl(MSR_K7_PERFCTR0 + i, pmc_now); | ||
283 | tsc_now = get_cycles_sync(); | ||
284 | } while ((tsc_now - tsc_start) < TICK_COUNT); | ||
285 | |||
286 | local_irq_restore(flags); | ||
287 | if (no_ctr_free) { | ||
288 | wrmsrl(MSR_K7_EVNTSEL3, 0); | ||
289 | wrmsrl(MSR_K7_PERFCTR3, pmc3); | ||
290 | wrmsrl(MSR_K7_EVNTSEL3, evntsel3); | ||
291 | } else { | ||
292 | release_perfctr_nmi(MSR_K7_PERFCTR0 + i); | ||
293 | release_evntsel_nmi(MSR_K7_EVNTSEL0 + i); | ||
294 | } | ||
295 | |||
296 | return pmc_now * tsc_khz / (tsc_now - tsc_start); | ||
297 | } | ||
252 | 298 | ||
253 | /* | 299 | /* |
254 | * pit_calibrate_tsc() uses the speaker output (channel 2) of | 300 | * pit_calibrate_tsc() uses the speaker output (channel 2) of |
@@ -336,14 +382,20 @@ void __init time_init(void) | |||
336 | if (hpet_use_timer) { | 382 | if (hpet_use_timer) { |
337 | /* set tick_nsec to use the proper rate for HPET */ | 383 | /* set tick_nsec to use the proper rate for HPET */ |
338 | tick_nsec = TICK_NSEC_HPET; | 384 | tick_nsec = TICK_NSEC_HPET; |
339 | cpu_khz = hpet_calibrate_tsc(); | 385 | tsc_khz = hpet_calibrate_tsc(); |
340 | timename = "HPET"; | 386 | timename = "HPET"; |
341 | } else { | 387 | } else { |
342 | pit_init(); | 388 | pit_init(); |
343 | cpu_khz = pit_calibrate_tsc(); | 389 | tsc_khz = pit_calibrate_tsc(); |
344 | timename = "PIT"; | 390 | timename = "PIT"; |
345 | } | 391 | } |
346 | 392 | ||
393 | cpu_khz = tsc_khz; | ||
394 | if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) && | ||
395 | boot_cpu_data.x86_vendor == X86_VENDOR_AMD && | ||
396 | boot_cpu_data.x86 == 16) | ||
397 | cpu_khz = tsc_calibrate_cpu_khz(); | ||
398 | |||
347 | if (unsynchronized_tsc()) | 399 | if (unsynchronized_tsc()) |
348 | mark_tsc_unstable(); | 400 | mark_tsc_unstable(); |
349 | 401 | ||
@@ -352,7 +404,7 @@ void __init time_init(void) | |||
352 | else | 404 | else |
353 | vgetcpu_mode = VGETCPU_LSL; | 405 | vgetcpu_mode = VGETCPU_LSL; |
354 | 406 | ||
355 | set_cyc2ns_scale(cpu_khz); | 407 | set_cyc2ns_scale(tsc_khz); |
356 | printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n", | 408 | printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n", |
357 | cpu_khz / 1000, cpu_khz % 1000); | 409 | cpu_khz / 1000, cpu_khz % 1000); |
358 | init_tsc_clocksource(); | 410 | init_tsc_clocksource(); |
diff --git a/arch/x86_64/kernel/tsc.c b/arch/x86_64/kernel/tsc.c index 1a0edbbffaa0..5c84992c676d 100644 --- a/arch/x86_64/kernel/tsc.c +++ b/arch/x86_64/kernel/tsc.c | |||
@@ -13,6 +13,8 @@ static int notsc __initdata = 0; | |||
13 | 13 | ||
14 | unsigned int cpu_khz; /* TSC clocks / usec, not used here */ | 14 | unsigned int cpu_khz; /* TSC clocks / usec, not used here */ |
15 | EXPORT_SYMBOL(cpu_khz); | 15 | EXPORT_SYMBOL(cpu_khz); |
16 | unsigned int tsc_khz; | ||
17 | EXPORT_SYMBOL(tsc_khz); | ||
16 | 18 | ||
17 | static unsigned int cyc2ns_scale __read_mostly; | 19 | static unsigned int cyc2ns_scale __read_mostly; |
18 | 20 | ||
@@ -77,7 +79,7 @@ static void handle_cpufreq_delayed_get(struct work_struct *v) | |||
77 | static unsigned int ref_freq = 0; | 79 | static unsigned int ref_freq = 0; |
78 | static unsigned long loops_per_jiffy_ref = 0; | 80 | static unsigned long loops_per_jiffy_ref = 0; |
79 | 81 | ||
80 | static unsigned long cpu_khz_ref = 0; | 82 | static unsigned long tsc_khz_ref = 0; |
81 | 83 | ||
82 | static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val, | 84 | static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val, |
83 | void *data) | 85 | void *data) |
@@ -99,7 +101,7 @@ static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val, | |||
99 | if (!ref_freq) { | 101 | if (!ref_freq) { |
100 | ref_freq = freq->old; | 102 | ref_freq = freq->old; |
101 | loops_per_jiffy_ref = *lpj; | 103 | loops_per_jiffy_ref = *lpj; |
102 | cpu_khz_ref = cpu_khz; | 104 | tsc_khz_ref = tsc_khz; |
103 | } | 105 | } |
104 | if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) || | 106 | if ((val == CPUFREQ_PRECHANGE && freq->old < freq->new) || |
105 | (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) || | 107 | (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) || |
@@ -107,12 +109,12 @@ static int time_cpufreq_notifier(struct notifier_block *nb, unsigned long val, | |||
107 | *lpj = | 109 | *lpj = |
108 | cpufreq_scale(loops_per_jiffy_ref, ref_freq, freq->new); | 110 | cpufreq_scale(loops_per_jiffy_ref, ref_freq, freq->new); |
109 | 111 | ||
110 | cpu_khz = cpufreq_scale(cpu_khz_ref, ref_freq, freq->new); | 112 | tsc_khz = cpufreq_scale(tsc_khz_ref, ref_freq, freq->new); |
111 | if (!(freq->flags & CPUFREQ_CONST_LOOPS)) | 113 | if (!(freq->flags & CPUFREQ_CONST_LOOPS)) |
112 | mark_tsc_unstable(); | 114 | mark_tsc_unstable(); |
113 | } | 115 | } |
114 | 116 | ||
115 | set_cyc2ns_scale(cpu_khz_ref); | 117 | set_cyc2ns_scale(tsc_khz_ref); |
116 | 118 | ||
117 | return 0; | 119 | return 0; |
118 | } | 120 | } |
@@ -213,7 +215,7 @@ EXPORT_SYMBOL_GPL(mark_tsc_unstable); | |||
213 | void __init init_tsc_clocksource(void) | 215 | void __init init_tsc_clocksource(void) |
214 | { | 216 | { |
215 | if (!notsc) { | 217 | if (!notsc) { |
216 | clocksource_tsc.mult = clocksource_khz2mult(cpu_khz, | 218 | clocksource_tsc.mult = clocksource_khz2mult(tsc_khz, |
217 | clocksource_tsc.shift); | 219 | clocksource_tsc.shift); |
218 | if (check_tsc_unstable()) | 220 | if (check_tsc_unstable()) |
219 | clocksource_tsc.rating = 0; | 221 | clocksource_tsc.rating = 0; |
diff --git a/arch/x86_64/kernel/tsc_sync.c b/arch/x86_64/kernel/tsc_sync.c index 014f0db45dfa..72d444dede9b 100644 --- a/arch/x86_64/kernel/tsc_sync.c +++ b/arch/x86_64/kernel/tsc_sync.c | |||
@@ -50,7 +50,7 @@ static __cpuinit void check_tsc_warp(void) | |||
50 | /* | 50 | /* |
51 | * The measurement runs for 20 msecs: | 51 | * The measurement runs for 20 msecs: |
52 | */ | 52 | */ |
53 | end = start + cpu_khz * 20ULL; | 53 | end = start + tsc_khz * 20ULL; |
54 | now = start; | 54 | now = start; |
55 | 55 | ||
56 | for (i = 0; ; i++) { | 56 | for (i = 0; ; i++) { |