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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 | 38 | #ifdef CONFIG_X86_64 |
28769149 | 39 | #include <asm/pgtable.h> |
2387ce57 | 40 | #endif |
28769149 | 41 | |
06a24dec TG |
42 | static inline void hpet_set_mapping(void) |
43 | { | |
44 | hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE); | |
2387ce57 YL |
45 | #ifdef CONFIG_X86_64 |
46 | __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE); | |
47 | #endif | |
06a24dec TG |
48 | } |
49 | ||
50 | static inline void hpet_clear_mapping(void) | |
51 | { | |
52 | iounmap(hpet_virt_address); | |
53 | hpet_virt_address = NULL; | |
54 | } | |
55 | ||
e9e2cdb4 TG |
56 | /* |
57 | * HPET command line enable / disable | |
58 | */ | |
59 | static int boot_hpet_disable; | |
b17530bd | 60 | int hpet_force_user; |
e9e2cdb4 TG |
61 | |
62 | static int __init hpet_setup(char* str) | |
63 | { | |
64 | if (str) { | |
65 | if (!strncmp("disable", str, 7)) | |
66 | boot_hpet_disable = 1; | |
b17530bd TG |
67 | if (!strncmp("force", str, 5)) |
68 | hpet_force_user = 1; | |
e9e2cdb4 TG |
69 | } |
70 | return 1; | |
71 | } | |
72 | __setup("hpet=", hpet_setup); | |
73 | ||
28769149 TG |
74 | static int __init disable_hpet(char *str) |
75 | { | |
76 | boot_hpet_disable = 1; | |
77 | return 1; | |
78 | } | |
79 | __setup("nohpet", disable_hpet); | |
80 | ||
e9e2cdb4 TG |
81 | static inline int is_hpet_capable(void) |
82 | { | |
83 | return (!boot_hpet_disable && hpet_address); | |
84 | } | |
85 | ||
86 | /* | |
87 | * HPET timer interrupt enable / disable | |
88 | */ | |
89 | static int hpet_legacy_int_enabled; | |
90 | ||
91 | /** | |
92 | * is_hpet_enabled - check whether the hpet timer interrupt is enabled | |
93 | */ | |
94 | int is_hpet_enabled(void) | |
95 | { | |
96 | return is_hpet_capable() && hpet_legacy_int_enabled; | |
97 | } | |
1bdbdaac | 98 | EXPORT_SYMBOL_GPL(is_hpet_enabled); |
e9e2cdb4 TG |
99 | |
100 | /* | |
101 | * When the hpet driver (/dev/hpet) is enabled, we need to reserve | |
102 | * timer 0 and timer 1 in case of RTC emulation. | |
103 | */ | |
104 | #ifdef CONFIG_HPET | |
105 | static void hpet_reserve_platform_timers(unsigned long id) | |
106 | { | |
107 | struct hpet __iomem *hpet = hpet_virt_address; | |
37a47db8 BR |
108 | struct hpet_timer __iomem *timer = &hpet->hpet_timers[2]; |
109 | unsigned int nrtimers, i; | |
e9e2cdb4 TG |
110 | struct hpet_data hd; |
111 | ||
112 | nrtimers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1; | |
113 | ||
114 | memset(&hd, 0, sizeof (hd)); | |
115 | hd.hd_phys_address = hpet_address; | |
06a24dec | 116 | hd.hd_address = hpet; |
e9e2cdb4 TG |
117 | hd.hd_nirqs = nrtimers; |
118 | hd.hd_flags = HPET_DATA_PLATFORM; | |
119 | hpet_reserve_timer(&hd, 0); | |
120 | ||
121 | #ifdef CONFIG_HPET_EMULATE_RTC | |
122 | hpet_reserve_timer(&hd, 1); | |
123 | #endif | |
5761d64b | 124 | |
e9e2cdb4 TG |
125 | hd.hd_irq[0] = HPET_LEGACY_8254; |
126 | hd.hd_irq[1] = HPET_LEGACY_RTC; | |
127 | ||
fc3fbc45 IM |
128 | for (i = 2; i < nrtimers; timer++, i++) { |
129 | hd.hd_irq[i] = (readl(&timer->hpet_config) & Tn_INT_ROUTE_CNF_MASK) >> | |
5761d64b | 130 | Tn_INT_ROUTE_CNF_SHIFT; |
fc3fbc45 | 131 | } |
5761d64b | 132 | |
e9e2cdb4 | 133 | hpet_alloc(&hd); |
5761d64b | 134 | |
e9e2cdb4 TG |
135 | } |
136 | #else | |
137 | static void hpet_reserve_platform_timers(unsigned long id) { } | |
138 | #endif | |
139 | ||
140 | /* | |
141 | * Common hpet info | |
142 | */ | |
143 | static unsigned long hpet_period; | |
144 | ||
610bf2f1 | 145 | static void hpet_legacy_set_mode(enum clock_event_mode mode, |
e9e2cdb4 | 146 | struct clock_event_device *evt); |
610bf2f1 | 147 | static int hpet_legacy_next_event(unsigned long delta, |
e9e2cdb4 TG |
148 | struct clock_event_device *evt); |
149 | ||
150 | /* | |
151 | * The hpet clock event device | |
152 | */ | |
153 | static struct clock_event_device hpet_clockevent = { | |
154 | .name = "hpet", | |
155 | .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, | |
610bf2f1 VP |
156 | .set_mode = hpet_legacy_set_mode, |
157 | .set_next_event = hpet_legacy_next_event, | |
e9e2cdb4 TG |
158 | .shift = 32, |
159 | .irq = 0, | |
59c69f2a | 160 | .rating = 50, |
e9e2cdb4 TG |
161 | }; |
162 | ||
163 | static void hpet_start_counter(void) | |
164 | { | |
165 | unsigned long cfg = hpet_readl(HPET_CFG); | |
166 | ||
167 | cfg &= ~HPET_CFG_ENABLE; | |
168 | hpet_writel(cfg, HPET_CFG); | |
169 | hpet_writel(0, HPET_COUNTER); | |
170 | hpet_writel(0, HPET_COUNTER + 4); | |
171 | cfg |= HPET_CFG_ENABLE; | |
172 | hpet_writel(cfg, HPET_CFG); | |
173 | } | |
174 | ||
59c69f2a VP |
175 | static void hpet_resume_device(void) |
176 | { | |
bfe0c1cc | 177 | force_hpet_resume(); |
59c69f2a VP |
178 | } |
179 | ||
180 | static void hpet_restart_counter(void) | |
181 | { | |
182 | hpet_resume_device(); | |
183 | hpet_start_counter(); | |
184 | } | |
185 | ||
610bf2f1 | 186 | static void hpet_enable_legacy_int(void) |
e9e2cdb4 TG |
187 | { |
188 | unsigned long cfg = hpet_readl(HPET_CFG); | |
189 | ||
190 | cfg |= HPET_CFG_LEGACY; | |
191 | hpet_writel(cfg, HPET_CFG); | |
192 | hpet_legacy_int_enabled = 1; | |
193 | } | |
194 | ||
610bf2f1 VP |
195 | static void hpet_legacy_clockevent_register(void) |
196 | { | |
610bf2f1 VP |
197 | /* Start HPET legacy interrupts */ |
198 | hpet_enable_legacy_int(); | |
199 | ||
200 | /* | |
6fd592da CM |
201 | * The mult factor is defined as (include/linux/clockchips.h) |
202 | * mult/2^shift = cyc/ns (in contrast to ns/cyc in clocksource.h) | |
203 | * hpet_period is in units of femtoseconds (per cycle), so | |
204 | * mult/2^shift = cyc/ns = 10^6/hpet_period | |
205 | * mult = (10^6 * 2^shift)/hpet_period | |
206 | * mult = (FSEC_PER_NSEC << hpet_clockevent.shift)/hpet_period | |
610bf2f1 | 207 | */ |
6fd592da CM |
208 | hpet_clockevent.mult = div_sc((unsigned long) FSEC_PER_NSEC, |
209 | hpet_period, hpet_clockevent.shift); | |
610bf2f1 VP |
210 | /* Calculate the min / max delta */ |
211 | hpet_clockevent.max_delta_ns = clockevent_delta2ns(0x7FFFFFFF, | |
212 | &hpet_clockevent); | |
213 | hpet_clockevent.min_delta_ns = clockevent_delta2ns(0x30, | |
214 | &hpet_clockevent); | |
215 | ||
216 | /* | |
217 | * Start hpet with the boot cpu mask and make it | |
218 | * global after the IO_APIC has been initialized. | |
219 | */ | |
220 | hpet_clockevent.cpumask = cpumask_of_cpu(smp_processor_id()); | |
221 | clockevents_register_device(&hpet_clockevent); | |
222 | global_clock_event = &hpet_clockevent; | |
223 | printk(KERN_DEBUG "hpet clockevent registered\n"); | |
224 | } | |
225 | ||
226 | static void hpet_legacy_set_mode(enum clock_event_mode mode, | |
e9e2cdb4 TG |
227 | struct clock_event_device *evt) |
228 | { | |
229 | unsigned long cfg, cmp, now; | |
230 | uint64_t delta; | |
231 | ||
232 | switch(mode) { | |
233 | case CLOCK_EVT_MODE_PERIODIC: | |
234 | delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * hpet_clockevent.mult; | |
235 | delta >>= hpet_clockevent.shift; | |
236 | now = hpet_readl(HPET_COUNTER); | |
237 | cmp = now + (unsigned long) delta; | |
238 | cfg = hpet_readl(HPET_T0_CFG); | |
239 | cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC | | |
240 | HPET_TN_SETVAL | HPET_TN_32BIT; | |
241 | hpet_writel(cfg, HPET_T0_CFG); | |
242 | /* | |
243 | * The first write after writing TN_SETVAL to the | |
244 | * config register sets the counter value, the second | |
245 | * write sets the period. | |
246 | */ | |
247 | hpet_writel(cmp, HPET_T0_CMP); | |
248 | udelay(1); | |
249 | hpet_writel((unsigned long) delta, HPET_T0_CMP); | |
250 | break; | |
251 | ||
252 | case CLOCK_EVT_MODE_ONESHOT: | |
253 | cfg = hpet_readl(HPET_T0_CFG); | |
254 | cfg &= ~HPET_TN_PERIODIC; | |
255 | cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; | |
256 | hpet_writel(cfg, HPET_T0_CFG); | |
257 | break; | |
258 | ||
259 | case CLOCK_EVT_MODE_UNUSED: | |
260 | case CLOCK_EVT_MODE_SHUTDOWN: | |
261 | cfg = hpet_readl(HPET_T0_CFG); | |
262 | cfg &= ~HPET_TN_ENABLE; | |
263 | hpet_writel(cfg, HPET_T0_CFG); | |
264 | break; | |
18de5bc4 TG |
265 | |
266 | case CLOCK_EVT_MODE_RESUME: | |
610bf2f1 | 267 | hpet_enable_legacy_int(); |
18de5bc4 | 268 | break; |
e9e2cdb4 TG |
269 | } |
270 | } | |
271 | ||
610bf2f1 | 272 | static int hpet_legacy_next_event(unsigned long delta, |
e9e2cdb4 TG |
273 | struct clock_event_device *evt) |
274 | { | |
275 | unsigned long cnt; | |
276 | ||
277 | cnt = hpet_readl(HPET_COUNTER); | |
278 | cnt += delta; | |
279 | hpet_writel(cnt, HPET_T0_CMP); | |
280 | ||
c7f6d15f | 281 | return ((long)(hpet_readl(HPET_COUNTER) - cnt ) > 0) ? -ETIME : 0; |
e9e2cdb4 TG |
282 | } |
283 | ||
6bb74df4 JS |
284 | /* |
285 | * Clock source related code | |
286 | */ | |
287 | static cycle_t read_hpet(void) | |
288 | { | |
289 | return (cycle_t)hpet_readl(HPET_COUNTER); | |
290 | } | |
291 | ||
28769149 TG |
292 | #ifdef CONFIG_X86_64 |
293 | static cycle_t __vsyscall_fn vread_hpet(void) | |
294 | { | |
295 | return readl((const void __iomem *)fix_to_virt(VSYSCALL_HPET) + 0xf0); | |
296 | } | |
297 | #endif | |
298 | ||
6bb74df4 JS |
299 | static struct clocksource clocksource_hpet = { |
300 | .name = "hpet", | |
301 | .rating = 250, | |
302 | .read = read_hpet, | |
303 | .mask = HPET_MASK, | |
304 | .shift = HPET_SHIFT, | |
305 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
59c69f2a | 306 | .resume = hpet_restart_counter, |
28769149 TG |
307 | #ifdef CONFIG_X86_64 |
308 | .vread = vread_hpet, | |
309 | #endif | |
6bb74df4 JS |
310 | }; |
311 | ||
610bf2f1 | 312 | static int hpet_clocksource_register(void) |
e9e2cdb4 | 313 | { |
6fd592da | 314 | u64 start, now; |
075bcd1f | 315 | cycle_t t1; |
e9e2cdb4 | 316 | |
e9e2cdb4 TG |
317 | /* Start the counter */ |
318 | hpet_start_counter(); | |
319 | ||
075bcd1f TG |
320 | /* Verify whether hpet counter works */ |
321 | t1 = read_hpet(); | |
322 | rdtscll(start); | |
323 | ||
324 | /* | |
325 | * We don't know the TSC frequency yet, but waiting for | |
326 | * 200000 TSC cycles is safe: | |
327 | * 4 GHz == 50us | |
328 | * 1 GHz == 200us | |
329 | */ | |
330 | do { | |
331 | rep_nop(); | |
332 | rdtscll(now); | |
333 | } while ((now - start) < 200000UL); | |
334 | ||
335 | if (t1 == read_hpet()) { | |
336 | printk(KERN_WARNING | |
337 | "HPET counter not counting. HPET disabled\n"); | |
610bf2f1 | 338 | return -ENODEV; |
075bcd1f TG |
339 | } |
340 | ||
6fd592da CM |
341 | /* |
342 | * The definition of mult is (include/linux/clocksource.h) | |
343 | * mult/2^shift = ns/cyc and hpet_period is in units of fsec/cyc | |
344 | * so we first need to convert hpet_period to ns/cyc units: | |
345 | * mult/2^shift = ns/cyc = hpet_period/10^6 | |
346 | * mult = (hpet_period * 2^shift)/10^6 | |
347 | * mult = (hpet_period << shift)/FSEC_PER_NSEC | |
6bb74df4 | 348 | */ |
6fd592da | 349 | clocksource_hpet.mult = div_sc(hpet_period, FSEC_PER_NSEC, HPET_SHIFT); |
6bb74df4 JS |
350 | |
351 | clocksource_register(&clocksource_hpet); | |
352 | ||
610bf2f1 VP |
353 | return 0; |
354 | } | |
355 | ||
b02a7f22 PM |
356 | /** |
357 | * hpet_enable - Try to setup the HPET timer. Returns 1 on success. | |
610bf2f1 VP |
358 | */ |
359 | int __init hpet_enable(void) | |
360 | { | |
361 | unsigned long id; | |
a6825f1c | 362 | int i; |
610bf2f1 VP |
363 | |
364 | if (!is_hpet_capable()) | |
365 | return 0; | |
366 | ||
367 | hpet_set_mapping(); | |
368 | ||
369 | /* | |
370 | * Read the period and check for a sane value: | |
371 | */ | |
372 | hpet_period = hpet_readl(HPET_PERIOD); | |
a6825f1c TG |
373 | |
374 | /* | |
375 | * AMD SB700 based systems with spread spectrum enabled use a | |
376 | * SMM based HPET emulation to provide proper frequency | |
377 | * setting. The SMM code is initialized with the first HPET | |
378 | * register access and takes some time to complete. During | |
379 | * this time the config register reads 0xffffffff. We check | |
380 | * for max. 1000 loops whether the config register reads a non | |
381 | * 0xffffffff value to make sure that HPET is up and running | |
382 | * before we go further. A counting loop is safe, as the HPET | |
383 | * access takes thousands of CPU cycles. On non SB700 based | |
384 | * machines this check is only done once and has no side | |
385 | * effects. | |
386 | */ | |
387 | for (i = 0; hpet_readl(HPET_CFG) == 0xFFFFFFFF; i++) { | |
388 | if (i == 1000) { | |
389 | printk(KERN_WARNING | |
390 | "HPET config register value = 0xFFFFFFFF. " | |
391 | "Disabling HPET\n"); | |
392 | goto out_nohpet; | |
393 | } | |
394 | } | |
395 | ||
610bf2f1 VP |
396 | if (hpet_period < HPET_MIN_PERIOD || hpet_period > HPET_MAX_PERIOD) |
397 | goto out_nohpet; | |
398 | ||
399 | /* | |
400 | * Read the HPET ID register to retrieve the IRQ routing | |
401 | * information and the number of channels | |
402 | */ | |
403 | id = hpet_readl(HPET_ID); | |
404 | ||
405 | #ifdef CONFIG_HPET_EMULATE_RTC | |
406 | /* | |
407 | * The legacy routing mode needs at least two channels, tick timer | |
408 | * and the rtc emulation channel. | |
409 | */ | |
410 | if (!(id & HPET_ID_NUMBER)) | |
411 | goto out_nohpet; | |
412 | #endif | |
413 | ||
414 | if (hpet_clocksource_register()) | |
415 | goto out_nohpet; | |
416 | ||
e9e2cdb4 | 417 | if (id & HPET_ID_LEGSUP) { |
610bf2f1 | 418 | hpet_legacy_clockevent_register(); |
e9e2cdb4 TG |
419 | return 1; |
420 | } | |
421 | return 0; | |
5d0cf410 | 422 | |
e9e2cdb4 | 423 | out_nohpet: |
06a24dec | 424 | hpet_clear_mapping(); |
399afa4f | 425 | boot_hpet_disable = 1; |
e9e2cdb4 TG |
426 | return 0; |
427 | } | |
428 | ||
28769149 TG |
429 | /* |
430 | * Needs to be late, as the reserve_timer code calls kalloc ! | |
431 | * | |
432 | * Not a problem on i386 as hpet_enable is called from late_time_init, | |
433 | * but on x86_64 it is necessary ! | |
434 | */ | |
435 | static __init int hpet_late_init(void) | |
436 | { | |
59c69f2a | 437 | if (boot_hpet_disable) |
28769149 TG |
438 | return -ENODEV; |
439 | ||
59c69f2a VP |
440 | if (!hpet_address) { |
441 | if (!force_hpet_address) | |
442 | return -ENODEV; | |
443 | ||
444 | hpet_address = force_hpet_address; | |
445 | hpet_enable(); | |
446 | if (!hpet_virt_address) | |
447 | return -ENODEV; | |
448 | } | |
449 | ||
28769149 | 450 | hpet_reserve_platform_timers(hpet_readl(HPET_ID)); |
59c69f2a | 451 | |
28769149 TG |
452 | return 0; |
453 | } | |
454 | fs_initcall(hpet_late_init); | |
455 | ||
c86c7fbc OH |
456 | void hpet_disable(void) |
457 | { | |
458 | if (is_hpet_capable()) { | |
459 | unsigned long cfg = hpet_readl(HPET_CFG); | |
460 | ||
461 | if (hpet_legacy_int_enabled) { | |
462 | cfg &= ~HPET_CFG_LEGACY; | |
463 | hpet_legacy_int_enabled = 0; | |
464 | } | |
465 | cfg &= ~HPET_CFG_ENABLE; | |
466 | hpet_writel(cfg, HPET_CFG); | |
467 | } | |
468 | } | |
469 | ||
e9e2cdb4 TG |
470 | #ifdef CONFIG_HPET_EMULATE_RTC |
471 | ||
472 | /* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET | |
473 | * is enabled, we support RTC interrupt functionality in software. | |
474 | * RTC has 3 kinds of interrupts: | |
475 | * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock | |
476 | * is updated | |
477 | * 2) Alarm Interrupt - generate an interrupt at a specific time of day | |
478 | * 3) Periodic Interrupt - generate periodic interrupt, with frequencies | |
479 | * 2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2) | |
480 | * (1) and (2) above are implemented using polling at a frequency of | |
481 | * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt | |
482 | * overhead. (DEFAULT_RTC_INT_FREQ) | |
483 | * For (3), we use interrupts at 64Hz or user specified periodic | |
484 | * frequency, whichever is higher. | |
485 | */ | |
486 | #include <linux/mc146818rtc.h> | |
487 | #include <linux/rtc.h> | |
1bdbdaac | 488 | #include <asm/rtc.h> |
e9e2cdb4 TG |
489 | |
490 | #define DEFAULT_RTC_INT_FREQ 64 | |
491 | #define DEFAULT_RTC_SHIFT 6 | |
492 | #define RTC_NUM_INTS 1 | |
493 | ||
494 | static unsigned long hpet_rtc_flags; | |
7e2a31da | 495 | static int hpet_prev_update_sec; |
e9e2cdb4 TG |
496 | static struct rtc_time hpet_alarm_time; |
497 | static unsigned long hpet_pie_count; | |
498 | static unsigned long hpet_t1_cmp; | |
499 | static unsigned long hpet_default_delta; | |
500 | static unsigned long hpet_pie_delta; | |
501 | static unsigned long hpet_pie_limit; | |
502 | ||
1bdbdaac BW |
503 | static rtc_irq_handler irq_handler; |
504 | ||
505 | /* | |
506 | * Registers a IRQ handler. | |
507 | */ | |
508 | int hpet_register_irq_handler(rtc_irq_handler handler) | |
509 | { | |
510 | if (!is_hpet_enabled()) | |
511 | return -ENODEV; | |
512 | if (irq_handler) | |
513 | return -EBUSY; | |
514 | ||
515 | irq_handler = handler; | |
516 | ||
517 | return 0; | |
518 | } | |
519 | EXPORT_SYMBOL_GPL(hpet_register_irq_handler); | |
520 | ||
521 | /* | |
522 | * Deregisters the IRQ handler registered with hpet_register_irq_handler() | |
523 | * and does cleanup. | |
524 | */ | |
525 | void hpet_unregister_irq_handler(rtc_irq_handler handler) | |
526 | { | |
527 | if (!is_hpet_enabled()) | |
528 | return; | |
529 | ||
530 | irq_handler = NULL; | |
531 | hpet_rtc_flags = 0; | |
532 | } | |
533 | EXPORT_SYMBOL_GPL(hpet_unregister_irq_handler); | |
534 | ||
e9e2cdb4 TG |
535 | /* |
536 | * Timer 1 for RTC emulation. We use one shot mode, as periodic mode | |
537 | * is not supported by all HPET implementations for timer 1. | |
538 | * | |
539 | * hpet_rtc_timer_init() is called when the rtc is initialized. | |
540 | */ | |
541 | int hpet_rtc_timer_init(void) | |
542 | { | |
543 | unsigned long cfg, cnt, delta, flags; | |
544 | ||
545 | if (!is_hpet_enabled()) | |
546 | return 0; | |
547 | ||
548 | if (!hpet_default_delta) { | |
549 | uint64_t clc; | |
550 | ||
551 | clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC; | |
552 | clc >>= hpet_clockevent.shift + DEFAULT_RTC_SHIFT; | |
553 | hpet_default_delta = (unsigned long) clc; | |
554 | } | |
555 | ||
556 | if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) | |
557 | delta = hpet_default_delta; | |
558 | else | |
559 | delta = hpet_pie_delta; | |
560 | ||
561 | local_irq_save(flags); | |
562 | ||
563 | cnt = delta + hpet_readl(HPET_COUNTER); | |
564 | hpet_writel(cnt, HPET_T1_CMP); | |
565 | hpet_t1_cmp = cnt; | |
566 | ||
567 | cfg = hpet_readl(HPET_T1_CFG); | |
568 | cfg &= ~HPET_TN_PERIODIC; | |
569 | cfg |= HPET_TN_ENABLE | HPET_TN_32BIT; | |
570 | hpet_writel(cfg, HPET_T1_CFG); | |
571 | ||
572 | local_irq_restore(flags); | |
573 | ||
574 | return 1; | |
575 | } | |
1bdbdaac | 576 | EXPORT_SYMBOL_GPL(hpet_rtc_timer_init); |
e9e2cdb4 TG |
577 | |
578 | /* | |
579 | * The functions below are called from rtc driver. | |
580 | * Return 0 if HPET is not being used. | |
581 | * Otherwise do the necessary changes and return 1. | |
582 | */ | |
583 | int hpet_mask_rtc_irq_bit(unsigned long bit_mask) | |
584 | { | |
585 | if (!is_hpet_enabled()) | |
586 | return 0; | |
587 | ||
588 | hpet_rtc_flags &= ~bit_mask; | |
589 | return 1; | |
590 | } | |
1bdbdaac | 591 | EXPORT_SYMBOL_GPL(hpet_mask_rtc_irq_bit); |
e9e2cdb4 TG |
592 | |
593 | int hpet_set_rtc_irq_bit(unsigned long bit_mask) | |
594 | { | |
595 | unsigned long oldbits = hpet_rtc_flags; | |
596 | ||
597 | if (!is_hpet_enabled()) | |
598 | return 0; | |
599 | ||
600 | hpet_rtc_flags |= bit_mask; | |
601 | ||
7e2a31da DB |
602 | if ((bit_mask & RTC_UIE) && !(oldbits & RTC_UIE)) |
603 | hpet_prev_update_sec = -1; | |
604 | ||
e9e2cdb4 TG |
605 | if (!oldbits) |
606 | hpet_rtc_timer_init(); | |
607 | ||
608 | return 1; | |
609 | } | |
1bdbdaac | 610 | EXPORT_SYMBOL_GPL(hpet_set_rtc_irq_bit); |
e9e2cdb4 TG |
611 | |
612 | int hpet_set_alarm_time(unsigned char hrs, unsigned char min, | |
613 | unsigned char sec) | |
614 | { | |
615 | if (!is_hpet_enabled()) | |
616 | return 0; | |
617 | ||
618 | hpet_alarm_time.tm_hour = hrs; | |
619 | hpet_alarm_time.tm_min = min; | |
620 | hpet_alarm_time.tm_sec = sec; | |
621 | ||
622 | return 1; | |
623 | } | |
1bdbdaac | 624 | EXPORT_SYMBOL_GPL(hpet_set_alarm_time); |
e9e2cdb4 TG |
625 | |
626 | int hpet_set_periodic_freq(unsigned long freq) | |
627 | { | |
628 | uint64_t clc; | |
629 | ||
630 | if (!is_hpet_enabled()) | |
631 | return 0; | |
632 | ||
633 | if (freq <= DEFAULT_RTC_INT_FREQ) | |
634 | hpet_pie_limit = DEFAULT_RTC_INT_FREQ / freq; | |
635 | else { | |
636 | clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC; | |
637 | do_div(clc, freq); | |
638 | clc >>= hpet_clockevent.shift; | |
639 | hpet_pie_delta = (unsigned long) clc; | |
640 | } | |
641 | return 1; | |
642 | } | |
1bdbdaac | 643 | EXPORT_SYMBOL_GPL(hpet_set_periodic_freq); |
e9e2cdb4 TG |
644 | |
645 | int hpet_rtc_dropped_irq(void) | |
646 | { | |
647 | return is_hpet_enabled(); | |
648 | } | |
1bdbdaac | 649 | EXPORT_SYMBOL_GPL(hpet_rtc_dropped_irq); |
e9e2cdb4 TG |
650 | |
651 | static void hpet_rtc_timer_reinit(void) | |
652 | { | |
653 | unsigned long cfg, delta; | |
654 | int lost_ints = -1; | |
655 | ||
656 | if (unlikely(!hpet_rtc_flags)) { | |
657 | cfg = hpet_readl(HPET_T1_CFG); | |
658 | cfg &= ~HPET_TN_ENABLE; | |
659 | hpet_writel(cfg, HPET_T1_CFG); | |
660 | return; | |
661 | } | |
662 | ||
663 | if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit) | |
664 | delta = hpet_default_delta; | |
665 | else | |
666 | delta = hpet_pie_delta; | |
667 | ||
668 | /* | |
669 | * Increment the comparator value until we are ahead of the | |
670 | * current count. | |
671 | */ | |
672 | do { | |
673 | hpet_t1_cmp += delta; | |
674 | hpet_writel(hpet_t1_cmp, HPET_T1_CMP); | |
675 | lost_ints++; | |
676 | } while ((long)(hpet_readl(HPET_COUNTER) - hpet_t1_cmp) > 0); | |
677 | ||
678 | if (lost_ints) { | |
679 | if (hpet_rtc_flags & RTC_PIE) | |
680 | hpet_pie_count += lost_ints; | |
681 | if (printk_ratelimit()) | |
7e2a31da | 682 | printk(KERN_WARNING "hpet1: lost %d rtc interrupts\n", |
e9e2cdb4 TG |
683 | lost_ints); |
684 | } | |
685 | } | |
686 | ||
687 | irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id) | |
688 | { | |
689 | struct rtc_time curr_time; | |
690 | unsigned long rtc_int_flag = 0; | |
691 | ||
692 | hpet_rtc_timer_reinit(); | |
1bdbdaac | 693 | memset(&curr_time, 0, sizeof(struct rtc_time)); |
e9e2cdb4 TG |
694 | |
695 | if (hpet_rtc_flags & (RTC_UIE | RTC_AIE)) | |
1bdbdaac | 696 | get_rtc_time(&curr_time); |
e9e2cdb4 TG |
697 | |
698 | if (hpet_rtc_flags & RTC_UIE && | |
699 | curr_time.tm_sec != hpet_prev_update_sec) { | |
7e2a31da DB |
700 | if (hpet_prev_update_sec >= 0) |
701 | rtc_int_flag = RTC_UF; | |
e9e2cdb4 TG |
702 | hpet_prev_update_sec = curr_time.tm_sec; |
703 | } | |
704 | ||
705 | if (hpet_rtc_flags & RTC_PIE && | |
706 | ++hpet_pie_count >= hpet_pie_limit) { | |
707 | rtc_int_flag |= RTC_PF; | |
708 | hpet_pie_count = 0; | |
709 | } | |
710 | ||
8ee291f8 | 711 | if (hpet_rtc_flags & RTC_AIE && |
e9e2cdb4 TG |
712 | (curr_time.tm_sec == hpet_alarm_time.tm_sec) && |
713 | (curr_time.tm_min == hpet_alarm_time.tm_min) && | |
714 | (curr_time.tm_hour == hpet_alarm_time.tm_hour)) | |
715 | rtc_int_flag |= RTC_AF; | |
716 | ||
717 | if (rtc_int_flag) { | |
718 | rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8)); | |
1bdbdaac BW |
719 | if (irq_handler) |
720 | irq_handler(rtc_int_flag, dev_id); | |
e9e2cdb4 TG |
721 | } |
722 | return IRQ_HANDLED; | |
723 | } | |
1bdbdaac | 724 | EXPORT_SYMBOL_GPL(hpet_rtc_interrupt); |
e9e2cdb4 | 725 | #endif |