aboutsummaryrefslogtreecommitdiffstats
path: root/arch/i386/kernel
diff options
context:
space:
mode:
Diffstat (limited to 'arch/i386/kernel')
-rw-r--r--arch/i386/kernel/hpet.c80
-rw-r--r--arch/i386/kernel/i8253.c2
-rw-r--r--arch/i386/kernel/setup.c1
-rw-r--r--arch/i386/kernel/time.c1
-rw-r--r--arch/i386/kernel/tsc.c83
5 files changed, 76 insertions, 91 deletions
diff --git a/arch/i386/kernel/hpet.c b/arch/i386/kernel/hpet.c
index e1006b7acc9e..f3ab61ee7498 100644
--- a/arch/i386/kernel/hpet.c
+++ b/arch/i386/kernel/hpet.c
@@ -201,12 +201,30 @@ static int hpet_next_event(unsigned long delta,
201} 201}
202 202
203/* 203/*
204 * Clock source related code
205 */
206static cycle_t read_hpet(void)
207{
208 return (cycle_t)hpet_readl(HPET_COUNTER);
209}
210
211static struct clocksource clocksource_hpet = {
212 .name = "hpet",
213 .rating = 250,
214 .read = read_hpet,
215 .mask = HPET_MASK,
216 .shift = HPET_SHIFT,
217 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
218};
219
220/*
204 * Try to setup the HPET timer 221 * Try to setup the HPET timer
205 */ 222 */
206int __init hpet_enable(void) 223int __init hpet_enable(void)
207{ 224{
208 unsigned long id; 225 unsigned long id;
209 uint64_t hpet_freq; 226 uint64_t hpet_freq;
227 u64 tmp;
210 228
211 if (!is_hpet_capable()) 229 if (!is_hpet_capable())
212 return 0; 230 return 0;
@@ -253,6 +271,25 @@ int __init hpet_enable(void)
253 /* Start the counter */ 271 /* Start the counter */
254 hpet_start_counter(); 272 hpet_start_counter();
255 273
274 /* Initialize and register HPET clocksource
275 *
276 * hpet period is in femto seconds per cycle
277 * so we need to convert this to ns/cyc units
278 * aproximated by mult/2^shift
279 *
280 * fsec/cyc * 1nsec/1000000fsec = nsec/cyc = mult/2^shift
281 * fsec/cyc * 1ns/1000000fsec * 2^shift = mult
282 * fsec/cyc * 2^shift * 1nsec/1000000fsec = mult
283 * (fsec/cyc << shift)/1000000 = mult
284 * (hpet_period << shift)/FSEC_PER_NSEC = mult
285 */
286 tmp = (u64)hpet_period << HPET_SHIFT;
287 do_div(tmp, FSEC_PER_NSEC);
288 clocksource_hpet.mult = (u32)tmp;
289
290 clocksource_register(&clocksource_hpet);
291
292
256 if (id & HPET_ID_LEGSUP) { 293 if (id & HPET_ID_LEGSUP) {
257 hpet_enable_int(); 294 hpet_enable_int();
258 hpet_reserve_platform_timers(id); 295 hpet_reserve_platform_timers(id);
@@ -273,49 +310,6 @@ out_nohpet:
273 return 0; 310 return 0;
274} 311}
275 312
276/*
277 * Clock source related code
278 */
279static cycle_t read_hpet(void)
280{
281 return (cycle_t)hpet_readl(HPET_COUNTER);
282}
283
284static struct clocksource clocksource_hpet = {
285 .name = "hpet",
286 .rating = 250,
287 .read = read_hpet,
288 .mask = HPET_MASK,
289 .shift = HPET_SHIFT,
290 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
291};
292
293static int __init init_hpet_clocksource(void)
294{
295 u64 tmp;
296
297 if (!hpet_virt_address)
298 return -ENODEV;
299
300 /*
301 * hpet period is in femto seconds per cycle
302 * so we need to convert this to ns/cyc units
303 * aproximated by mult/2^shift
304 *
305 * fsec/cyc * 1nsec/1000000fsec = nsec/cyc = mult/2^shift
306 * fsec/cyc * 1ns/1000000fsec * 2^shift = mult
307 * fsec/cyc * 2^shift * 1nsec/1000000fsec = mult
308 * (fsec/cyc << shift)/1000000 = mult
309 * (hpet_period << shift)/FSEC_PER_NSEC = mult
310 */
311 tmp = (u64)hpet_period << HPET_SHIFT;
312 do_div(tmp, FSEC_PER_NSEC);
313 clocksource_hpet.mult = (u32)tmp;
314
315 return clocksource_register(&clocksource_hpet);
316}
317
318module_init(init_hpet_clocksource);
319 313
320#ifdef CONFIG_HPET_EMULATE_RTC 314#ifdef CONFIG_HPET_EMULATE_RTC
321 315
diff --git a/arch/i386/kernel/i8253.c b/arch/i386/kernel/i8253.c
index a6bc7bb38834..5cbb776b3089 100644
--- a/arch/i386/kernel/i8253.c
+++ b/arch/i386/kernel/i8253.c
@@ -195,4 +195,4 @@ static int __init init_pit_clocksource(void)
195 clocksource_pit.mult = clocksource_hz2mult(CLOCK_TICK_RATE, 20); 195 clocksource_pit.mult = clocksource_hz2mult(CLOCK_TICK_RATE, 20);
196 return clocksource_register(&clocksource_pit); 196 return clocksource_register(&clocksource_pit);
197} 197}
198module_init(init_pit_clocksource); 198arch_initcall(init_pit_clocksource);
diff --git a/arch/i386/kernel/setup.c b/arch/i386/kernel/setup.c
index 122623dcc6e1..698c24fe482e 100644
--- a/arch/i386/kernel/setup.c
+++ b/arch/i386/kernel/setup.c
@@ -657,5 +657,4 @@ void __init setup_arch(char **cmdline_p)
657 conswitchp = &dummy_con; 657 conswitchp = &dummy_con;
658#endif 658#endif
659#endif 659#endif
660 tsc_init();
661} 660}
diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c
index ccd3734edb8f..94e5cb091104 100644
--- a/arch/i386/kernel/time.c
+++ b/arch/i386/kernel/time.c
@@ -279,5 +279,6 @@ void __init hpet_time_init(void)
279 */ 279 */
280void __init time_init(void) 280void __init time_init(void)
281{ 281{
282 tsc_init();
282 late_time_init = choose_time_init(); 283 late_time_init = choose_time_init();
283} 284}
diff --git a/arch/i386/kernel/tsc.c b/arch/i386/kernel/tsc.c
index 59222a04234b..875d8a6ecc02 100644
--- a/arch/i386/kernel/tsc.c
+++ b/arch/i386/kernel/tsc.c
@@ -184,34 +184,6 @@ int recalibrate_cpu_khz(void)
184 184
185EXPORT_SYMBOL(recalibrate_cpu_khz); 185EXPORT_SYMBOL(recalibrate_cpu_khz);
186 186
187void __init tsc_init(void)
188{
189 if (!cpu_has_tsc || tsc_disable)
190 goto out_no_tsc;
191
192 cpu_khz = calculate_cpu_khz();
193 tsc_khz = cpu_khz;
194
195 if (!cpu_khz)
196 goto out_no_tsc;
197
198 printk("Detected %lu.%03lu MHz processor.\n",
199 (unsigned long)cpu_khz / 1000,
200 (unsigned long)cpu_khz % 1000);
201
202 set_cyc2ns_scale(cpu_khz);
203 use_tsc_delay();
204 return;
205
206out_no_tsc:
207 /*
208 * Set the tsc_disable flag if there's no TSC support, this
209 * makes it a fast flag for the kernel to see whether it
210 * should be using the TSC.
211 */
212 tsc_disable = 1;
213}
214
215#ifdef CONFIG_CPU_FREQ 187#ifdef CONFIG_CPU_FREQ
216 188
217/* 189/*
@@ -381,28 +353,47 @@ static void __init check_geode_tsc_reliable(void)
381static inline void check_geode_tsc_reliable(void) { } 353static inline void check_geode_tsc_reliable(void) { }
382#endif 354#endif
383 355
384static int __init init_tsc_clocksource(void) 356
357void __init tsc_init(void)
385{ 358{
359 if (!cpu_has_tsc || tsc_disable)
360 goto out_no_tsc;
386 361
387 if (cpu_has_tsc && tsc_khz && !tsc_disable) { 362 cpu_khz = calculate_cpu_khz();
388 /* check blacklist */ 363 tsc_khz = cpu_khz;
389 dmi_check_system(bad_tsc_dmi_table);
390 364
391 unsynchronized_tsc(); 365 if (!cpu_khz)
392 check_geode_tsc_reliable(); 366 goto out_no_tsc;
393 current_tsc_khz = tsc_khz;
394 clocksource_tsc.mult = clocksource_khz2mult(current_tsc_khz,
395 clocksource_tsc.shift);
396 /* lower the rating if we already know its unstable: */
397 if (check_tsc_unstable()) {
398 clocksource_tsc.rating = 0;
399 clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS;
400 }
401 367
402 return clocksource_register(&clocksource_tsc); 368 printk("Detected %lu.%03lu MHz processor.\n",
369 (unsigned long)cpu_khz / 1000,
370 (unsigned long)cpu_khz % 1000);
371
372 set_cyc2ns_scale(cpu_khz);
373 use_tsc_delay();
374
375 /* Check and install the TSC clocksource */
376 dmi_check_system(bad_tsc_dmi_table);
377
378 unsynchronized_tsc();
379 check_geode_tsc_reliable();
380 current_tsc_khz = tsc_khz;
381 clocksource_tsc.mult = clocksource_khz2mult(current_tsc_khz,
382 clocksource_tsc.shift);
383 /* lower the rating if we already know its unstable: */
384 if (check_tsc_unstable()) {
385 clocksource_tsc.rating = 0;
386 clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS;
403 } 387 }
388 clocksource_register(&clocksource_tsc);
404 389
405 return 0; 390 return;
406}
407 391
408module_init(init_tsc_clocksource); 392out_no_tsc:
393 /*
394 * Set the tsc_disable flag if there's no TSC support, this
395 * makes it a fast flag for the kernel to see whether it
396 * should be using the TSC.
397 */
398 tsc_disable = 1;
399}