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-rw-r--r--arch/x86/kernel/time_64.c2
-rw-r--r--arch/x86/kernel/tsc_32.c5
-rw-r--r--include/linux/delay.h1
-rw-r--r--init/calibrate.c36
4 files changed, 27 insertions, 17 deletions
diff --git a/arch/x86/kernel/time_64.c b/arch/x86/kernel/time_64.c
index c737849e2ef7..12b4a71bd074 100644
--- a/arch/x86/kernel/time_64.c
+++ b/arch/x86/kernel/time_64.c
@@ -123,6 +123,8 @@ void __init time_init(void)
123 (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)) 123 (boot_cpu_data.x86_vendor == X86_VENDOR_AMD))
124 cpu_khz = calculate_cpu_khz(); 124 cpu_khz = calculate_cpu_khz();
125 125
126 lpj_tsc = ((unsigned long)tsc_khz * 1000)/HZ;
127
126 if (unsynchronized_tsc()) 128 if (unsynchronized_tsc())
127 mark_tsc_unstable("TSCs unsynchronized"); 129 mark_tsc_unstable("TSCs unsynchronized");
128 130
diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c
index 068759db63dd..be729035b30b 100644
--- a/arch/x86/kernel/tsc_32.c
+++ b/arch/x86/kernel/tsc_32.c
@@ -401,6 +401,7 @@ static inline void check_geode_tsc_reliable(void) { }
401void __init tsc_init(void) 401void __init tsc_init(void)
402{ 402{
403 int cpu; 403 int cpu;
404 u64 lpj;
404 405
405 if (!cpu_has_tsc || tsc_disabled) { 406 if (!cpu_has_tsc || tsc_disabled) {
406 /* Disable the TSC in case of !cpu_has_tsc */ 407 /* Disable the TSC in case of !cpu_has_tsc */
@@ -421,6 +422,10 @@ void __init tsc_init(void)
421 return; 422 return;
422 } 423 }
423 424
425 lpj = ((u64)tsc_khz * 1000);
426 do_div(lpj, HZ);
427 lpj_tsc = lpj;
428
424 printk("Detected %lu.%03lu MHz processor.\n", 429 printk("Detected %lu.%03lu MHz processor.\n",
425 (unsigned long)cpu_khz / 1000, 430 (unsigned long)cpu_khz / 1000,
426 (unsigned long)cpu_khz % 1000); 431 (unsigned long)cpu_khz % 1000);
diff --git a/include/linux/delay.h b/include/linux/delay.h
index 54552d21296e..01aec60590ab 100644
--- a/include/linux/delay.h
+++ b/include/linux/delay.h
@@ -41,6 +41,7 @@ static inline void ndelay(unsigned long x)
41#define ndelay(x) ndelay(x) 41#define ndelay(x) ndelay(x)
42#endif 42#endif
43 43
44extern unsigned long lpj_tsc;
44void calibrate_delay(void); 45void calibrate_delay(void);
45void msleep(unsigned int msecs); 46void msleep(unsigned int msecs);
46unsigned long msleep_interruptible(unsigned int msecs); 47unsigned long msleep_interruptible(unsigned int msecs);
diff --git a/init/calibrate.c b/init/calibrate.c
index ecb3822d4f70..86286974dada 100644
--- a/init/calibrate.c
+++ b/init/calibrate.c
@@ -8,7 +8,9 @@
8#include <linux/delay.h> 8#include <linux/delay.h>
9#include <linux/init.h> 9#include <linux/init.h>
10#include <linux/timex.h> 10#include <linux/timex.h>
11#include <linux/smp.h>
11 12
13unsigned long lpj_tsc;
12unsigned long preset_lpj; 14unsigned long preset_lpj;
13static int __init lpj_setup(char *str) 15static int __init lpj_setup(char *str)
14{ 16{
@@ -108,6 +110,10 @@ static unsigned long __cpuinit calibrate_delay_direct(void) {return 0;}
108 * This is the number of bits of precision for the loops_per_jiffy. Each 110 * This is the number of bits of precision for the loops_per_jiffy. Each
109 * bit takes on average 1.5/HZ seconds. This (like the original) is a little 111 * bit takes on average 1.5/HZ seconds. This (like the original) is a little
110 * better than 1% 112 * better than 1%
113 * For the boot cpu we can skip the delay calibration and assign it a value
114 * calculated based on the tsc frequency.
115 * For the rest of the CPUs we cannot assume that the tsc frequency is same as
116 * the cpu frequency, hence do the calibration for those.
111 */ 117 */
112#define LPS_PREC 8 118#define LPS_PREC 8
113 119
@@ -118,20 +124,20 @@ void __cpuinit calibrate_delay(void)
118 124
119 if (preset_lpj) { 125 if (preset_lpj) {
120 loops_per_jiffy = preset_lpj; 126 loops_per_jiffy = preset_lpj;
121 printk("Calibrating delay loop (skipped)... " 127 printk(KERN_INFO
122 "%lu.%02lu BogoMIPS preset\n", 128 "Calibrating delay loop (skipped) preset value.. ");
123 loops_per_jiffy/(500000/HZ), 129 } else if ((smp_processor_id() == 0) && lpj_tsc) {
124 (loops_per_jiffy/(5000/HZ)) % 100); 130 loops_per_jiffy = lpj_tsc;
131 printk(KERN_INFO
132 "Calibrating delay loop (skipped), "
133 "using tsc calculated value.. ");
125 } else if ((loops_per_jiffy = calibrate_delay_direct()) != 0) { 134 } else if ((loops_per_jiffy = calibrate_delay_direct()) != 0) {
126 printk("Calibrating delay using timer specific routine.. "); 135 printk(KERN_INFO
127 printk("%lu.%02lu BogoMIPS (lpj=%lu)\n", 136 "Calibrating delay using timer specific routine.. ");
128 loops_per_jiffy/(500000/HZ),
129 (loops_per_jiffy/(5000/HZ)) % 100,
130 loops_per_jiffy);
131 } else { 137 } else {
132 loops_per_jiffy = (1<<12); 138 loops_per_jiffy = (1<<12);
133 139
134 printk(KERN_DEBUG "Calibrating delay loop... "); 140 printk(KERN_INFO "Calibrating delay loop... ");
135 while ((loops_per_jiffy <<= 1) != 0) { 141 while ((loops_per_jiffy <<= 1) != 0) {
136 /* wait for "start of" clock tick */ 142 /* wait for "start of" clock tick */
137 ticks = jiffies; 143 ticks = jiffies;
@@ -161,12 +167,8 @@ void __cpuinit calibrate_delay(void)
161 if (jiffies != ticks) /* longer than 1 tick */ 167 if (jiffies != ticks) /* longer than 1 tick */
162 loops_per_jiffy &= ~loopbit; 168 loops_per_jiffy &= ~loopbit;
163 } 169 }
164
165 /* Round the value and print it */
166 printk("%lu.%02lu BogoMIPS (lpj=%lu)\n",
167 loops_per_jiffy/(500000/HZ),
168 (loops_per_jiffy/(5000/HZ)) % 100,
169 loops_per_jiffy);
170 } 170 }
171 171 printk(KERN_INFO "%lu.%02lu BogoMIPS (lpj=%lu)\n",
172 loops_per_jiffy/(500000/HZ),
173 (loops_per_jiffy/(5000/HZ)) % 100, loops_per_jiffy);
172} 174}