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Commit | Line | Data |
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5d0cf410 | 1 | #include <linux/clocksource.h> |
e9e2cdb4 | 2 | #include <linux/clockchips.h> |
28769149 | 3 | #include <linux/delay.h> |
5d0cf410 JS |
4 | #include <linux/errno.h> |
5 | #include <linux/hpet.h> | |
6 | #include <linux/init.h> | |
399afa4f ML |
7 | #include <linux/sysdev.h> |
8 | #include <linux/pm.h> | |
5d0cf410 | 9 | |
28769149 | 10 | #include <asm/fixmap.h> |
5d0cf410 | 11 | #include <asm/hpet.h> |
06a24dec | 12 | #include <asm/i8253.h> |
5d0cf410 JS |
13 | #include <asm/io.h> |
14 | ||
7f9f303a | 15 | #define HPET_MASK CLOCKSOURCE_MASK(32) |
5d0cf410 JS |
16 | #define HPET_SHIFT 22 |
17 | ||
b10db7f0 PM |
18 | /* FSEC = 10^-15 |
19 | NSEC = 10^-9 */ | |
6fd592da | 20 | #define FSEC_PER_NSEC 1000000L |
5d0cf410 | 21 | |
e9e2cdb4 TG |
22 | /* |
23 | * HPET address is set in acpi/boot.c, when an ACPI entry exists | |
24 | */ | |
25 | unsigned long hpet_address; | |
06a24dec | 26 | static void __iomem *hpet_virt_address; |
e9e2cdb4 | 27 | |
31c435d7 | 28 | unsigned long hpet_readl(unsigned long a) |
e9e2cdb4 TG |
29 | { |
30 | return readl(hpet_virt_address + a); | |
31 | } | |
32 | ||
33 | static inline void hpet_writel(unsigned long d, unsigned long a) | |
34 | { | |
35 | writel(d, hpet_virt_address + a); | |
36 | } | |
37 | ||
28769149 TG |
38 | #ifdef CONFIG_X86_64 |
39 | ||
40 | #include <asm/pgtable.h> | |
41 | ||
42 | static inline void hpet_set_mapping(void) | |
43 | { | |
44 | set_fixmap_nocache(FIX_HPET_BASE, hpet_address); | |
45 | __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE); | |
46 | hpet_virt_address = (void __iomem *)fix_to_virt(FIX_HPET_BASE); | |
47 | } | |
48 | ||
49 | static inline void hpet_clear_mapping(void) | |
50 | { | |
51 | hpet_virt_address = NULL; | |
52 | } | |
53 | ||
54 | #else | |
55 | ||
06a24dec TG |
56 | static inline void hpet_set_mapping(void) |
57 | { | |
58 | hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE); | |
59 | } | |
60 | ||
61 | static inline void hpet_clear_mapping(void) | |
62 | { | |
63 | iounmap(hpet_virt_address); | |
64 | hpet_virt_address = NULL; | |
65 | } | |
28769149 | 66 | #endif |
06a24dec | 67 | |
e9e2cdb4 TG |
68 | /* |
69 | * HPET command line enable / disable | |
70 | */ | |
71 | static int boot_hpet_disable; | |
b17530bd | 72 | int hpet_force_user; |
e9e2cdb4 TG |
73 | |
74 | static int __init hpet_setup(char* str) | |
75 | { | |
76 | if (str) { | |
77 | if (!strncmp("disable", str, 7)) | |
78 | boot_hpet_disable = 1; | |
b17530bd TG |
79 | if (!strncmp("force", str, 5)) |
80 | hpet_force_user = 1; | |
e9e2cdb4 TG |
81 | } |
82 | return 1; | |
83 | } | |
84 | __setup("hpet=", hpet_setup); | |
85 | ||
28769149 TG |
86 | static int __init disable_hpet(char *str) |
87 | { | |
88 | boot_hpet_disable = 1; | |
89 | return 1; | |
90 | } | |
91 | __setup("nohpet", disable_hpet); | |
92 | ||
e9e2cdb4 TG |
93 | static inline int is_hpet_capable(void) |
94 | { | |
95 | return (!boot_hpet_disable && hpet_address); | |
96 | } | |
97 | ||
98 | /* | |
99 | * HPET timer interrupt enable / disable | |
100 | */ | |
101 | static int hpet_legacy_int_enabled; | |
102 | ||
103 | /** | |
104 | * is_hpet_enabled - check whether the hpet timer interrupt is enabled | |
105 | */ | |
106 | int is_hpet_enabled(void) | |
107 | { | |
108 | return is_hpet_capable() && hpet_legacy_int_enabled; | |
109 | } | |
1bdbdaac | 110 | EXPORT_SYMBOL_GPL(is_hpet_enabled); |
e9e2cdb4 TG |
111 | |
112 | /* | |
113 | * When the hpet driver (/dev/hpet) is enabled, we need to reserve | |
114 | * timer 0 and timer 1 in case of RTC emulation. | |
115 | */ | |
116 | #ifdef CONFIG_HPET | |
117 | static void hpet_reserve_platform_timers(unsigned long id) | |
118 | { | |
119 | struct hpet __iomem *hpet = hpet_virt_address; | |
37a47db8 BR |
120 | struct hpet_timer __iomem *timer = &hpet->hpet_timers[2]; |
121 | unsigned int nrtimers, i; | |
e9e2cdb4 TG |
122 | struct hpet_data hd; |
123 | ||
124 | nrtimers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1; | |
125 | ||
126 | memset(&hd, 0, sizeof (hd)); | |
127 | hd.hd_phys_address = hpet_address; | |
06a24dec | 128 | hd.hd_address = hpet; |
e9e2cdb4 TG |
129 | hd.hd_nirqs = nrtimers; |
130 | hd.hd_flags = HPET_DATA_PLATFORM; | |
131 | hpet_reserve_timer(&hd, 0); | |
132 | ||
133 | #ifdef CONFIG_HPET_EMULATE_RTC | |
134 | hpet_reserve_timer(&hd, 1); | |
135 | #endif | |
5761d64b | 136 | |
e9e2cdb4 TG |
137 | hd.hd_irq[0] = HPET_LEGACY_8254; |
138 | hd.hd_irq[1] = HPET_LEGACY_RTC; | |
139 | ||
fc3fbc45 IM |
140 | for (i = 2; i < nrtimers; timer++, i++) { |
141 | hd.hd_irq[i] = (readl(&timer->hpet_config) & Tn_INT_ROUTE_CNF_MASK) >> | |
5761d64b | 142 | Tn_INT_ROUTE_CNF_SHIFT; |
fc3fbc45 | 143 | } |
5761d64b | 144 | |
e9e2cdb4 | 145 | hpet_alloc(&hd); |
5761d64b | 146 | |
e9e2cdb4 TG |
147 | } |
148 | #else | |
149 | static void hpet_reserve_platform_timers(unsigned long id) { } | |
150 | #endif | |
151 | ||
152 | /* | |
153 | * Common hpet info | |
154 | */ | |
155 | static unsigned long hpet_period; | |
156 | ||
610bf2f1 | 157 | static void hpet_legacy_set_mode(enum clock_event_mode mode, |
e9e2cdb4 | 158 | struct clock_event_device *evt); |
610bf2f1 | 159 | static int hpet_legacy_next_event(unsigned long delta, |
e9e2cdb4 TG |
160 | struct clock_event_device *evt); |
161 | ||
162 | /* | |
163 | * The hpet clock event device | |
164 | */ | |
165 | static struct clock_event_device hpet_clockevent = { | |
166 | .name = "hpet", | |
167 | .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, | |
610bf2f1 VP |
168 | .set_mode = hpet_legacy_set_mode, |
169 | .set_next_event = hpet_legacy_next_event, | |
e9e2cdb4 TG |
170 | .shift = 32, |
171 | .irq = 0, | |
59c69f2a | 172 | .rating = 50, |
e9e2cdb4 TG |
173 | }; |
174 | ||
175 | static void hpet_start_counter(void) | |
176 | { | |
177 | unsigned long cfg = hpet_readl(HPET_CFG); | |
178 | ||
179 | cfg &= ~HPET_CFG_ENABLE; | |
180 | hpet_writel(cfg, HPET_CFG); | |
181 | hpet_writel(0, HPET_COUNTER); | |
182 | hpet_writel(0, HPET_COUNTER + 4); | |
183 | cfg |= HPET_CFG_ENABLE; | |
184 | hpet_writel(cfg, HPET_CFG); | |
185 | } | |
186 | ||
59c69f2a VP |
187 | static void hpet_resume_device(void) |
188 | { | |
bfe0c1cc | 189 | force_hpet_resume(); |
59c69f2a VP |
190 | } |
191 | ||
192 | static void hpet_restart_counter(void) | |
193 | { | |
194 | hpet_resume_device(); | |
195 | hpet_start_counter(); | |
196 | } | |
197 | ||
610bf2f1 | 198 | static void hpet_enable_legacy_int(void) |
e9e2cdb4 TG |
199 | { |
200 | unsigned long cfg = hpet_readl(HPET_CFG); | |
201 | ||
202 | cfg |= HPET_CFG_LEGACY; | |
203 | hpet_writel(cfg, HPET_CFG); | |
204 | hpet_legacy_int_enabled = 1; | |
205 | } | |
206 | ||
610bf2f1 VP |
207 | static void hpet_legacy_clockevent_register(void) |
208 | { | |
610bf2f1 VP |
209 | /* Start HPET legacy interrupts */ |
210 | hpet_enable_legacy_int(); | |
211 | ||
212 | /* | |
6fd592da CM |
213 | * The mult factor is defined as (include/linux/clockchips.h) |
214 | * mult/2^shift = cyc/ns (in contrast to ns/cyc in clocksource.h) | |
215 | * hpet_period is in units of femtoseconds (per cycle), so | |
216 | * mult/2^shift = cyc/ns = 10^6/hpet_period | |
217 | * mult = (10^6 * 2^shift)/hpet_period | |
218 | * mult = (FSEC_PER_NSEC << hpet_clockevent.shift)/hpet_period | |
610bf2f1 | 219 | */ |
6fd592da CM |
220 | hpet_clockevent.mult = div_sc((unsigned long) FSEC_PER_NSEC, |
221 | hpet_period, hpet_clockevent.shift); | |
610bf2f1 VP |
222 | /* Calculate the min / max delta */ |
223 | hpet_clockevent.max_delta_ns = clockevent_delta2ns(0x7FFFFFFF, | |
224 | &hpet_clockevent); | |
225 | hpet_clockevent.min_delta_ns = clockevent_delta2ns(0x30, | |
226 | &hpet_clockevent); | |
227 | ||
228 | /* | |
229 | * Start hpet with the boot cpu mask and make it | |
230 | * global after the IO_APIC has been initialized. | |
231 | */ | |
232 | hpet_clockevent.cpumask = cpumask_of_cpu(smp_processor_id()); | |
233 | clockevents_register_device(&hpet_clockevent); | |
234 | global_clock_event = &hpet_clockevent; | |
235 | printk(KERN_DEBUG "hpet clockevent registered\n"); | |
236 | } | |
237 | ||
238 | static void hpet_legacy_set_mode(enum clock_event_mode mode, | |
e9e2cdb4 TG |
239 | struct clock_event_device *evt) |
240 | { | |
241 | unsigned long cfg, cmp, now; | |
242 | uint64_t delta; | |
243 | ||
244 | switch(mode) { | |
245 | case CLOCK_EVT_MODE_PERIODIC: | |
246 | delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * hpet_clockevent.mult; | |
247 | delta >>= hpet_clockevent.shift; | |
248 | now = hpet_readl(HPET_COUNTER); | |
249 | cmp = now + (unsigned long) delta; | |
250 | cfg = hpet_readl(HPET_T0_CFG); | |
251 | cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC | | |
252 | HPET_TN_SETVAL | HPET_TN_32BIT; | |
253 | hpet_writel(cfg, HPET_T0_CFG); | |
254 | /* | |
255 | * The first write after writing TN_SETVAL to the | |
256 | * config register sets the counter value, the second | |
257 | * write sets the period. | |
258 | */ | |
259 | hpet_writel(cmp, HPET_T0_CMP); | |
260 | udelay(1); | |
261 | hpet_writel((unsigned long) delta, HPET_T0_CMP); | |
262 | break; | |
263 | ||
264 | case CLOCK_EVT_MODE_ONESHOT: | |
265 | cfg = hpet_readl(HPET_T0_CFG); | |
266 | cfg &= ~HPET_TN_PERIODIC; | |
267 | cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; | |
268 | hpet_writel(cfg, HPET_T0_CFG); | |
269 | break; | |
270 | ||
271 | case CLOCK_EVT_MODE_UNUSED: | |
272 | case CLOCK_EVT_MODE_SHUTDOWN: | |
273 | cfg = hpet_readl(HPET_T0_CFG); | |
274 | cfg &= ~HPET_TN_ENABLE; | |
275 | hpet_writel(cfg, HPET_T0_CFG); | |
276 | break; | |
18de5bc4 TG |
277 | |
278 | case CLOCK_EVT_MODE_RESUME: | |
610bf2f1 | 279 | hpet_enable_legacy_int(); |
18de5bc4 | 280 | break; |
e9e2cdb4 TG |
281 | } |
282 | } | |
283 | ||
610bf2f1 | 284 | static int hpet_legacy_next_event(unsigned long delta, |
e9e2cdb4 TG |
285 | struct clock_event_device *evt) |
286 | { | |
287 | unsigned long cnt; | |
288 | ||
289 | cnt = hpet_readl(HPET_COUNTER); | |
290 | cnt += delta; | |
291 | hpet_writel(cnt, HPET_T0_CMP); | |
292 | ||
c7f6d15f | 293 | return ((long)(hpet_readl(HPET_COUNTER) - cnt ) > 0) ? -ETIME : 0; |
e9e2cdb4 TG |
294 | } |
295 | ||
6bb74df4 JS |
296 | /* |
297 | * Clock source related code | |
298 | */ | |
299 | static cycle_t read_hpet(void) | |
300 | { | |
301 | return (cycle_t)hpet_readl(HPET_COUNTER); | |
302 | } | |
303 | ||
28769149 TG |
304 | #ifdef CONFIG_X86_64 |
305 | static cycle_t __vsyscall_fn vread_hpet(void) | |
306 | { | |
307 | return readl((const void __iomem *)fix_to_virt(VSYSCALL_HPET) + 0xf0); | |
308 | } | |
309 | #endif | |
310 | ||
6bb74df4 JS |
311 | static struct clocksource clocksource_hpet = { |
312 | .name = "hpet", | |
313 | .rating = 250, | |
314 | .read = read_hpet, | |
315 | .mask = HPET_MASK, | |
316 | .shift = HPET_SHIFT, | |
317 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
59c69f2a | 318 | .resume = hpet_restart_counter, |
28769149 TG |
319 | #ifdef CONFIG_X86_64 |
320 | .vread = vread_hpet, | |
321 | #endif | |
6bb74df4 JS |
322 | }; |
323 | ||
610bf2f1 | 324 | static int hpet_clocksource_register(void) |
e9e2cdb4 | 325 | { |
6fd592da | 326 | u64 start, now; |
075bcd1f | 327 | cycle_t t1; |
e9e2cdb4 | 328 | |
e9e2cdb4 TG |
329 | /* Start the counter */ |
330 | hpet_start_counter(); | |
331 | ||
075bcd1f TG |
332 | /* Verify whether hpet counter works */ |
333 | t1 = read_hpet(); | |
334 | rdtscll(start); | |
335 | ||
336 | /* | |
337 | * We don't know the TSC frequency yet, but waiting for | |
338 | * 200000 TSC cycles is safe: | |
339 | * 4 GHz == 50us | |
340 | * 1 GHz == 200us | |
341 | */ | |
342 | do { | |
343 | rep_nop(); | |
344 | rdtscll(now); | |
345 | } while ((now - start) < 200000UL); | |
346 | ||
347 | if (t1 == read_hpet()) { | |
348 | printk(KERN_WARNING | |
349 | "HPET counter not counting. HPET disabled\n"); | |
610bf2f1 | 350 | return -ENODEV; |
075bcd1f TG |
351 | } |
352 | ||
6fd592da CM |
353 | /* |
354 | * The definition of mult is (include/linux/clocksource.h) | |
355 | * mult/2^shift = ns/cyc and hpet_period is in units of fsec/cyc | |
356 | * so we first need to convert hpet_period to ns/cyc units: | |
357 | * mult/2^shift = ns/cyc = hpet_period/10^6 | |
358 | * mult = (hpet_period * 2^shift)/10^6 | |
359 | * mult = (hpet_period << shift)/FSEC_PER_NSEC | |
6bb74df4 | 360 | */ |
6fd592da | 361 | clocksource_hpet.mult = div_sc(hpet_period, FSEC_PER_NSEC, HPET_SHIFT); |
6bb74df4 JS |
362 | |
363 | clocksource_register(&clocksource_hpet); | |
364 | ||
610bf2f1 VP |
365 | return 0; |
366 | } | |
367 | ||
b02a7f22 PM |
368 | /** |
369 | * hpet_enable - Try to setup the HPET timer. Returns 1 on success. | |
610bf2f1 VP |
370 | */ |
371 | int __init hpet_enable(void) | |
372 | { | |
373 | unsigned long id; | |
374 | ||
375 | if (!is_hpet_capable()) | |
376 | return 0; | |
377 | ||
378 | hpet_set_mapping(); | |
379 | ||
380 | /* | |
381 | * Read the period and check for a sane value: | |
382 | */ | |
383 | hpet_period = hpet_readl(HPET_PERIOD); | |
384 | if (hpet_period < HPET_MIN_PERIOD || hpet_period > HPET_MAX_PERIOD) | |
385 | goto out_nohpet; | |
386 | ||
387 | /* | |
388 | * Read the HPET ID register to retrieve the IRQ routing | |
389 | * information and the number of channels | |
390 | */ | |
391 | id = hpet_readl(HPET_ID); | |
392 | ||
393 | #ifdef CONFIG_HPET_EMULATE_RTC | |
394 | /* | |
395 | * The legacy routing mode needs at least two channels, tick timer | |
396 | * and the rtc emulation channel. | |
397 | */ | |
398 | if (!(id & HPET_ID_NUMBER)) | |
399 | goto out_nohpet; | |
400 | #endif | |
401 | ||
402 | if (hpet_clocksource_register()) | |
403 | goto out_nohpet; | |
404 | ||
e9e2cdb4 | 405 | if (id & HPET_ID_LEGSUP) { |
610bf2f1 | 406 | hpet_legacy_clockevent_register(); |
e9e2cdb4 TG |
407 | return 1; |
408 | } | |
409 | return 0; | |
5d0cf410 | 410 | |
e9e2cdb4 | 411 | out_nohpet: |
06a24dec | 412 | hpet_clear_mapping(); |
399afa4f | 413 | boot_hpet_disable = 1; |
e9e2cdb4 TG |
414 | return 0; |
415 | } | |
416 | ||
28769149 TG |
417 | /* |
418 | * Needs to be late, as the reserve_timer code calls kalloc ! | |
419 | * | |
420 | * Not a problem on i386 as hpet_enable is called from late_time_init, | |
421 | * but on x86_64 it is necessary ! | |
422 | */ | |
423 | static __init int hpet_late_init(void) | |
424 | { | |
59c69f2a | 425 | if (boot_hpet_disable) |
28769149 TG |
426 | return -ENODEV; |
427 | ||
59c69f2a VP |
428 | if (!hpet_address) { |
429 | if (!force_hpet_address) | |
430 | return -ENODEV; | |
431 | ||
432 | hpet_address = force_hpet_address; | |
433 | hpet_enable(); | |
434 | if (!hpet_virt_address) | |
435 | return -ENODEV; | |
436 | } | |
437 | ||
28769149 | 438 | hpet_reserve_platform_timers(hpet_readl(HPET_ID)); |
59c69f2a | 439 | |
28769149 TG |
440 | return 0; |
441 | } | |
442 | fs_initcall(hpet_late_init); | |
443 | ||
c86c7fbc OH |
444 | void hpet_disable(void) |
445 | { | |
446 | if (is_hpet_capable()) { | |
447 | unsigned long cfg = hpet_readl(HPET_CFG); | |
448 | ||
449 | if (hpet_legacy_int_enabled) { | |
450 | cfg &= ~HPET_CFG_LEGACY; | |
451 | hpet_legacy_int_enabled = 0; | |
452 | } | |
453 | cfg &= ~HPET_CFG_ENABLE; | |
454 | hpet_writel(cfg, HPET_CFG); | |
455 | } | |
456 | } | |
457 | ||
e9e2cdb4 TG |
458 | #ifdef CONFIG_HPET_EMULATE_RTC |
459 | ||
460 | /* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET | |
461 | * is enabled, we support RTC interrupt functionality in software. | |
462 | * RTC has 3 kinds of interrupts: | |
463 | * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock | |
464 | * is updated | |
465 | * 2) Alarm Interrupt - generate an interrupt at a specific time of day | |
466 | * 3) Periodic Interrupt - generate periodic interrupt, with frequencies | |
467 | * 2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2) | |
468 | * (1) and (2) above are implemented using polling at a frequency of | |
469 | * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt | |
470 | * overhead. (DEFAULT_RTC_INT_FREQ) | |
471 | * For (3), we use interrupts at 64Hz or user specified periodic | |
472 | * frequency, whichever is higher. | |
473 | */ | |
474 | #include <linux/mc146818rtc.h> | |
475 | #include <linux/rtc.h> | |
1bdbdaac | 476 | #include <asm/rtc.h> |
e9e2cdb4 TG |
477 | |
478 | #define DEFAULT_RTC_INT_FREQ 64 | |
479 | #define DEFAULT_RTC_SHIFT 6 | |
480 | #define RTC_NUM_INTS 1 | |
481 | ||
482 | static unsigned long hpet_rtc_flags; | |
483 | static unsigned long hpet_prev_update_sec; | |
484 | static struct rtc_time hpet_alarm_time; | |
485 | static unsigned long hpet_pie_count; | |
486 | static unsigned long hpet_t1_cmp; | |
487 | static unsigned long hpet_default_delta; | |
488 | static unsigned long hpet_pie_delta; | |
489 | static unsigned long hpet_pie_limit; | |
490 | ||
1bdbdaac BW |
491 | static rtc_irq_handler irq_handler; |
492 | ||
493 | /* | |
494 | * Registers a IRQ handler. | |
495 | */ | |
496 | int hpet_register_irq_handler(rtc_irq_handler handler) | |
497 | { | |
498 | if (!is_hpet_enabled()) | |
499 | return -ENODEV; | |
500 | if (irq_handler) | |
501 | return -EBUSY; | |
502 | ||
503 | irq_handler = handler; | |
504 | ||
505 | return 0; | |
506 | } | |
507 | EXPORT_SYMBOL_GPL(hpet_register_irq_handler); | |
508 | ||
509 | /* | |
510 | * Deregisters the IRQ handler registered with hpet_register_irq_handler() | |
511 | * and does cleanup. | |
512 | */ | |
513 | void hpet_unregister_irq_handler(rtc_irq_handler handler) | |
514 | { | |
515 | if (!is_hpet_enabled()) | |
516 | return; | |
517 | ||
518 | irq_handler = NULL; | |
519 | hpet_rtc_flags = 0; | |
520 | } | |
521 | EXPORT_SYMBOL_GPL(hpet_unregister_irq_handler); | |
522 | ||
e9e2cdb4 TG |
523 | /* |
524 | * Timer 1 for RTC emulation. We use one shot mode, as periodic mode | |
525 | * is not supported by all HPET implementations for timer 1. | |
526 | * | |
527 | * hpet_rtc_timer_init() is called when the rtc is initialized. | |
528 | */ | |
529 | int hpet_rtc_timer_init(void) | |
530 | { | |
531 | unsigned long cfg, cnt, delta, flags; | |
532 | ||
533 | if (!is_hpet_enabled()) | |
534 | return 0; | |
535 | ||
536 | if (!hpet_default_delta) { | |
537 | uint64_t clc; | |
538 | ||
539 | clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC; | |
540 | clc >>= hpet_clockevent.shift + DEFAULT_RTC_SHIFT; | |
541 | hpet_default_delta = (unsigned long) clc; | |
542 | } | |
543 | ||
544 | if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) | |
545 | delta = hpet_default_delta; | |
546 | else | |
547 | delta = hpet_pie_delta; | |
548 | ||
549 | local_irq_save(flags); | |
550 | ||
551 | cnt = delta + hpet_readl(HPET_COUNTER); | |
552 | hpet_writel(cnt, HPET_T1_CMP); | |
553 | hpet_t1_cmp = cnt; | |
554 | ||
555 | cfg = hpet_readl(HPET_T1_CFG); | |
556 | cfg &= ~HPET_TN_PERIODIC; | |
557 | cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; | |
558 | hpet_writel(cfg, HPET_T1_CFG); | |
559 | ||
560 | local_irq_restore(flags); | |
561 | ||
562 | return 1; | |
563 | } | |
1bdbdaac | 564 | EXPORT_SYMBOL_GPL(hpet_rtc_timer_init); |
e9e2cdb4 TG |
565 | |
566 | /* | |
567 | * The functions below are called from rtc driver. | |
568 | * Return 0 if HPET is not being used. | |
569 | * Otherwise do the necessary changes and return 1. | |
570 | */ | |
571 | int hpet_mask_rtc_irq_bit(unsigned long bit_mask) | |
572 | { | |
573 | if (!is_hpet_enabled()) | |
574 | return 0; | |
575 | ||
576 | hpet_rtc_flags &= ~bit_mask; | |
577 | return 1; | |
578 | } | |
1bdbdaac | 579 | EXPORT_SYMBOL_GPL(hpet_mask_rtc_irq_bit); |
e9e2cdb4 TG |
580 | |
581 | int hpet_set_rtc_irq_bit(unsigned long bit_mask) | |
582 | { | |
583 | unsigned long oldbits = hpet_rtc_flags; | |
584 | ||
585 | if (!is_hpet_enabled()) | |
586 | return 0; | |
587 | ||
588 | hpet_rtc_flags |= bit_mask; | |
589 | ||
590 | if (!oldbits) | |
591 | hpet_rtc_timer_init(); | |
592 | ||
593 | return 1; | |
594 | } | |
1bdbdaac | 595 | EXPORT_SYMBOL_GPL(hpet_set_rtc_irq_bit); |
e9e2cdb4 TG |
596 | |
597 | int hpet_set_alarm_time(unsigned char hrs, unsigned char min, | |
598 | unsigned char sec) | |
599 | { | |
600 | if (!is_hpet_enabled()) | |
601 | return 0; | |
602 | ||
603 | hpet_alarm_time.tm_hour = hrs; | |
604 | hpet_alarm_time.tm_min = min; | |
605 | hpet_alarm_time.tm_sec = sec; | |
606 | ||
607 | return 1; | |
608 | } | |
1bdbdaac | 609 | EXPORT_SYMBOL_GPL(hpet_set_alarm_time); |
e9e2cdb4 TG |
610 | |
611 | int hpet_set_periodic_freq(unsigned long freq) | |
612 | { | |
613 | uint64_t clc; | |
614 | ||
615 | if (!is_hpet_enabled()) | |
616 | return 0; | |
617 | ||
618 | if (freq <= DEFAULT_RTC_INT_FREQ) | |
619 | hpet_pie_limit = DEFAULT_RTC_INT_FREQ / freq; | |
620 | else { | |
621 | clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC; | |
622 | do_div(clc, freq); | |
623 | clc >>= hpet_clockevent.shift; | |
624 | hpet_pie_delta = (unsigned long) clc; | |
625 | } | |
626 | return 1; | |
627 | } | |
1bdbdaac | 628 | EXPORT_SYMBOL_GPL(hpet_set_periodic_freq); |
e9e2cdb4 TG |
629 | |
630 | int hpet_rtc_dropped_irq(void) | |
631 | { | |
632 | return is_hpet_enabled(); | |
633 | } | |
1bdbdaac | 634 | EXPORT_SYMBOL_GPL(hpet_rtc_dropped_irq); |
e9e2cdb4 TG |
635 | |
636 | static void hpet_rtc_timer_reinit(void) | |
637 | { | |
638 | unsigned long cfg, delta; | |
639 | int lost_ints = -1; | |
640 | ||
641 | if (unlikely(!hpet_rtc_flags)) { | |
642 | cfg = hpet_readl(HPET_T1_CFG); | |
643 | cfg &= ~HPET_TN_ENABLE; | |
644 | hpet_writel(cfg, HPET_T1_CFG); | |
645 | return; | |
646 | } | |
647 | ||
648 | if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) | |
649 | delta = hpet_default_delta; | |
650 | else | |
651 | delta = hpet_pie_delta; | |
652 | ||
653 | /* | |
654 | * Increment the comparator value until we are ahead of the | |
655 | * current count. | |
656 | */ | |
657 | do { | |
658 | hpet_t1_cmp += delta; | |
659 | hpet_writel(hpet_t1_cmp, HPET_T1_CMP); | |
660 | lost_ints++; | |
661 | } while ((long)(hpet_readl(HPET_COUNTER) - hpet_t1_cmp) > 0); | |
662 | ||
663 | if (lost_ints) { | |
664 | if (hpet_rtc_flags & RTC_PIE) | |
665 | hpet_pie_count += lost_ints; | |
666 | if (printk_ratelimit()) | |
667 | printk(KERN_WARNING "rtc: lost %d interrupts\n", | |
668 | lost_ints); | |
669 | } | |
670 | } | |
671 | ||
672 | irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) | |
673 | { | |
674 | struct rtc_time curr_time; | |
675 | unsigned long rtc_int_flag = 0; | |
676 | ||
677 | hpet_rtc_timer_reinit(); | |
1bdbdaac | 678 | memset(&curr_time, 0, sizeof(struct rtc_time)); |
e9e2cdb4 TG |
679 | |
680 | if (hpet_rtc_flags & (RTC_UIE | RTC_AIE)) | |
1bdbdaac | 681 | get_rtc_time(&curr_time); |
e9e2cdb4 TG |
682 | |
683 | if (hpet_rtc_flags & RTC_UIE && | |
684 | curr_time.tm_sec != hpet_prev_update_sec) { | |
685 | rtc_int_flag = RTC_UF; | |
686 | hpet_prev_update_sec = curr_time.tm_sec; | |
687 | } | |
688 | ||
689 | if (hpet_rtc_flags & RTC_PIE && | |
690 | ++hpet_pie_count >= hpet_pie_limit) { | |
691 | rtc_int_flag |= RTC_PF; | |
692 | hpet_pie_count = 0; | |
693 | } | |
694 | ||
8ee291f8 | 695 | if (hpet_rtc_flags & RTC_AIE && |
e9e2cdb4 TG |
696 | (curr_time.tm_sec == hpet_alarm_time.tm_sec) && |
697 | (curr_time.tm_min == hpet_alarm_time.tm_min) && | |
698 | (curr_time.tm_hour == hpet_alarm_time.tm_hour)) | |
699 | rtc_int_flag |= RTC_AF; | |
700 | ||
701 | if (rtc_int_flag) { | |
702 | rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8)); | |
1bdbdaac BW |
703 | if (irq_handler) |
704 | irq_handler(rtc_int_flag, dev_id); | |
e9e2cdb4 TG |
705 | } |
706 | return IRQ_HANDLED; | |
707 | } | |
1bdbdaac | 708 | EXPORT_SYMBOL_GPL(hpet_rtc_interrupt); |
e9e2cdb4 | 709 | #endif |