Commit | Line | Data |
---|---|---|
7837699f SY |
1 | /* |
2 | * 8253/8254 interval timer emulation | |
3 | * | |
4 | * Copyright (c) 2003-2004 Fabrice Bellard | |
5 | * Copyright (c) 2006 Intel Corporation | |
6 | * Copyright (c) 2007 Keir Fraser, XenSource Inc | |
7 | * Copyright (c) 2008 Intel Corporation | |
9611c187 | 8 | * Copyright 2009 Red Hat, Inc. and/or its affiliates. |
7837699f SY |
9 | * |
10 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
11 | * of this software and associated documentation files (the "Software"), to deal | |
12 | * in the Software without restriction, including without limitation the rights | |
13 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
14 | * copies of the Software, and to permit persons to whom the Software is | |
15 | * furnished to do so, subject to the following conditions: | |
16 | * | |
17 | * The above copyright notice and this permission notice shall be included in | |
18 | * all copies or substantial portions of the Software. | |
19 | * | |
20 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
21 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
22 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
23 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
24 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
25 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
26 | * THE SOFTWARE. | |
27 | * | |
28 | * Authors: | |
29 | * Sheng Yang <sheng.yang@intel.com> | |
30 | * Based on QEMU and Xen. | |
31 | */ | |
32 | ||
a78d9626 JP |
33 | #define pr_fmt(fmt) "pit: " fmt |
34 | ||
7837699f | 35 | #include <linux/kvm_host.h> |
5a0e3ad6 | 36 | #include <linux/slab.h> |
7837699f | 37 | |
49df6397 | 38 | #include "ioapic.h" |
7837699f SY |
39 | #include "irq.h" |
40 | #include "i8254.h" | |
9ed96e87 | 41 | #include "x86.h" |
7837699f SY |
42 | |
43 | #ifndef CONFIG_X86_64 | |
6f6d6a1a | 44 | #define mod_64(x, y) ((x) - (y) * div64_u64(x, y)) |
7837699f SY |
45 | #else |
46 | #define mod_64(x, y) ((x) % (y)) | |
47 | #endif | |
48 | ||
49 | #define RW_STATE_LSB 1 | |
50 | #define RW_STATE_MSB 2 | |
51 | #define RW_STATE_WORD0 3 | |
52 | #define RW_STATE_WORD1 4 | |
53 | ||
54 | /* Compute with 96 bit intermediate result: (a*b)/c */ | |
55 | static u64 muldiv64(u64 a, u32 b, u32 c) | |
56 | { | |
57 | union { | |
58 | u64 ll; | |
59 | struct { | |
60 | u32 low, high; | |
61 | } l; | |
62 | } u, res; | |
63 | u64 rl, rh; | |
64 | ||
65 | u.ll = a; | |
66 | rl = (u64)u.l.low * (u64)b; | |
67 | rh = (u64)u.l.high * (u64)b; | |
68 | rh += (rl >> 32); | |
6f6d6a1a RZ |
69 | res.l.high = div64_u64(rh, c); |
70 | res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c); | |
7837699f SY |
71 | return res.ll; |
72 | } | |
73 | ||
09edea72 | 74 | static void pit_set_gate(struct kvm_pit *pit, int channel, u32 val) |
7837699f | 75 | { |
09edea72 | 76 | struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; |
7837699f | 77 | |
7837699f SY |
78 | switch (c->mode) { |
79 | default: | |
80 | case 0: | |
81 | case 4: | |
82 | /* XXX: just disable/enable counting */ | |
83 | break; | |
84 | case 1: | |
85 | case 2: | |
86 | case 3: | |
87 | case 5: | |
88 | /* Restart counting on rising edge. */ | |
89 | if (c->gate < val) | |
90 | c->count_load_time = ktime_get(); | |
91 | break; | |
92 | } | |
93 | ||
94 | c->gate = val; | |
95 | } | |
96 | ||
09edea72 | 97 | static int pit_get_gate(struct kvm_pit *pit, int channel) |
7837699f | 98 | { |
09edea72 | 99 | return pit->pit_state.channels[channel].gate; |
7837699f SY |
100 | } |
101 | ||
09edea72 | 102 | static s64 __kpit_elapsed(struct kvm_pit *pit) |
fd668423 MT |
103 | { |
104 | s64 elapsed; | |
105 | ktime_t remaining; | |
09edea72 | 106 | struct kvm_kpit_state *ps = &pit->pit_state; |
fd668423 | 107 | |
26ef1924 | 108 | if (!ps->period) |
0ff77873 MT |
109 | return 0; |
110 | ||
ede2ccc5 MT |
111 | /* |
112 | * The Counter does not stop when it reaches zero. In | |
113 | * Modes 0, 1, 4, and 5 the Counter ``wraps around'' to | |
114 | * the highest count, either FFFF hex for binary counting | |
115 | * or 9999 for BCD counting, and continues counting. | |
116 | * Modes 2 and 3 are periodic; the Counter reloads | |
117 | * itself with the initial count and continues counting | |
118 | * from there. | |
119 | */ | |
26ef1924 AK |
120 | remaining = hrtimer_get_remaining(&ps->timer); |
121 | elapsed = ps->period - ktime_to_ns(remaining); | |
fd668423 MT |
122 | |
123 | return elapsed; | |
124 | } | |
125 | ||
09edea72 | 126 | static s64 kpit_elapsed(struct kvm_pit *pit, struct kvm_kpit_channel_state *c, |
fd668423 MT |
127 | int channel) |
128 | { | |
129 | if (channel == 0) | |
09edea72 | 130 | return __kpit_elapsed(pit); |
fd668423 MT |
131 | |
132 | return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time)); | |
133 | } | |
134 | ||
09edea72 | 135 | static int pit_get_count(struct kvm_pit *pit, int channel) |
7837699f | 136 | { |
09edea72 | 137 | struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; |
7837699f SY |
138 | s64 d, t; |
139 | int counter; | |
140 | ||
09edea72 | 141 | t = kpit_elapsed(pit, c, channel); |
7837699f SY |
142 | d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC); |
143 | ||
144 | switch (c->mode) { | |
145 | case 0: | |
146 | case 1: | |
147 | case 4: | |
148 | case 5: | |
149 | counter = (c->count - d) & 0xffff; | |
150 | break; | |
151 | case 3: | |
152 | /* XXX: may be incorrect for odd counts */ | |
153 | counter = c->count - (mod_64((2 * d), c->count)); | |
154 | break; | |
155 | default: | |
156 | counter = c->count - mod_64(d, c->count); | |
157 | break; | |
158 | } | |
159 | return counter; | |
160 | } | |
161 | ||
09edea72 | 162 | static int pit_get_out(struct kvm_pit *pit, int channel) |
7837699f | 163 | { |
09edea72 | 164 | struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; |
7837699f SY |
165 | s64 d, t; |
166 | int out; | |
167 | ||
09edea72 | 168 | t = kpit_elapsed(pit, c, channel); |
7837699f SY |
169 | d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC); |
170 | ||
171 | switch (c->mode) { | |
172 | default: | |
173 | case 0: | |
174 | out = (d >= c->count); | |
175 | break; | |
176 | case 1: | |
177 | out = (d < c->count); | |
178 | break; | |
179 | case 2: | |
180 | out = ((mod_64(d, c->count) == 0) && (d != 0)); | |
181 | break; | |
182 | case 3: | |
183 | out = (mod_64(d, c->count) < ((c->count + 1) >> 1)); | |
184 | break; | |
185 | case 4: | |
186 | case 5: | |
187 | out = (d == c->count); | |
188 | break; | |
189 | } | |
190 | ||
191 | return out; | |
192 | } | |
193 | ||
09edea72 | 194 | static void pit_latch_count(struct kvm_pit *pit, int channel) |
7837699f | 195 | { |
09edea72 | 196 | struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; |
7837699f | 197 | |
7837699f | 198 | if (!c->count_latched) { |
09edea72 | 199 | c->latched_count = pit_get_count(pit, channel); |
7837699f SY |
200 | c->count_latched = c->rw_mode; |
201 | } | |
202 | } | |
203 | ||
09edea72 | 204 | static void pit_latch_status(struct kvm_pit *pit, int channel) |
7837699f | 205 | { |
09edea72 | 206 | struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; |
7837699f | 207 | |
7837699f SY |
208 | if (!c->status_latched) { |
209 | /* TODO: Return NULL COUNT (bit 6). */ | |
09edea72 | 210 | c->status = ((pit_get_out(pit, channel) << 7) | |
7837699f SY |
211 | (c->rw_mode << 4) | |
212 | (c->mode << 1) | | |
213 | c->bcd); | |
214 | c->status_latched = 1; | |
215 | } | |
216 | } | |
217 | ||
ee032c99 | 218 | static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) |
3cf57fed MT |
219 | { |
220 | struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state, | |
221 | irq_ack_notifier); | |
33572ac0 | 222 | |
ddf54503 RK |
223 | atomic_set(&ps->irq_ack, 1); |
224 | /* irq_ack should be set before pending is read. Order accesses with | |
225 | * inc(pending) in pit_timer_fn and xchg(irq_ack, 0) in pit_do_work. | |
226 | */ | |
227 | smp_mb(); | |
71474e2f | 228 | if (atomic_dec_if_positive(&ps->pending) > 0) |
b6ddf05f | 229 | queue_kthread_work(&ps->pit->worker, &ps->pit->expired); |
3cf57fed MT |
230 | } |
231 | ||
2f599714 MT |
232 | void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu) |
233 | { | |
234 | struct kvm_pit *pit = vcpu->kvm->arch.vpit; | |
235 | struct hrtimer *timer; | |
236 | ||
c5af89b6 | 237 | if (!kvm_vcpu_is_bsp(vcpu) || !pit) |
2f599714 MT |
238 | return; |
239 | ||
26ef1924 | 240 | timer = &pit->pit_state.timer; |
2febc839 | 241 | mutex_lock(&pit->pit_state.lock); |
2f599714 | 242 | if (hrtimer_cancel(timer)) |
beb20d52 | 243 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS); |
2febc839 | 244 | mutex_unlock(&pit->pit_state.lock); |
2f599714 MT |
245 | } |
246 | ||
33572ac0 | 247 | static void destroy_pit_timer(struct kvm_pit *pit) |
7837699f | 248 | { |
26ef1924 | 249 | hrtimer_cancel(&pit->pit_state.timer); |
b6ddf05f | 250 | flush_kthread_work(&pit->expired); |
7837699f SY |
251 | } |
252 | ||
b6ddf05f | 253 | static void pit_do_work(struct kthread_work *work) |
33572ac0 CL |
254 | { |
255 | struct kvm_pit *pit = container_of(work, struct kvm_pit, expired); | |
256 | struct kvm *kvm = pit->kvm; | |
257 | struct kvm_vcpu *vcpu; | |
258 | int i; | |
259 | struct kvm_kpit_state *ps = &pit->pit_state; | |
33572ac0 | 260 | |
ddf54503 RK |
261 | if (ps->reinject && !atomic_xchg(&ps->irq_ack, 0)) |
262 | return; | |
263 | ||
264 | kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1, false); | |
265 | kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0, false); | |
266 | ||
267 | /* | |
268 | * Provides NMI watchdog support via Virtual Wire mode. | |
269 | * The route is: PIT -> LVT0 in NMI mode. | |
270 | * | |
271 | * Note: Our Virtual Wire implementation does not follow | |
272 | * the MP specification. We propagate a PIT interrupt to all | |
273 | * VCPUs and only when LVT0 is in NMI mode. The interrupt can | |
274 | * also be simultaneously delivered through PIC and IOAPIC. | |
33572ac0 | 275 | */ |
ddf54503 RK |
276 | if (atomic_read(&kvm->arch.vapics_in_nmi_mode) > 0) |
277 | kvm_for_each_vcpu(i, vcpu, kvm) | |
278 | kvm_apic_nmi_wd_deliver(vcpu); | |
33572ac0 CL |
279 | } |
280 | ||
281 | static enum hrtimer_restart pit_timer_fn(struct hrtimer *data) | |
282 | { | |
26ef1924 AK |
283 | struct kvm_kpit_state *ps = container_of(data, struct kvm_kpit_state, timer); |
284 | struct kvm_pit *pt = ps->kvm->arch.vpit; | |
33572ac0 | 285 | |
7dd0fdff | 286 | if (ps->reinject) |
26ef1924 | 287 | atomic_inc(&ps->pending); |
7dd0fdff RK |
288 | |
289 | queue_kthread_work(&pt->worker, &pt->expired); | |
33572ac0 | 290 | |
26ef1924 AK |
291 | if (ps->is_periodic) { |
292 | hrtimer_add_expires_ns(&ps->timer, ps->period); | |
33572ac0 CL |
293 | return HRTIMER_RESTART; |
294 | } else | |
295 | return HRTIMER_NORESTART; | |
296 | } | |
297 | ||
fd700a00 RK |
298 | static inline void kvm_pit_reset_reinject(struct kvm_pit *pit) |
299 | { | |
300 | atomic_set(&pit->pit_state.pending, 0); | |
ddf54503 | 301 | atomic_set(&pit->pit_state.irq_ack, 1); |
fd700a00 RK |
302 | } |
303 | ||
71474e2f RK |
304 | void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject) |
305 | { | |
306 | struct kvm_kpit_state *ps = &pit->pit_state; | |
307 | struct kvm *kvm = pit->kvm; | |
308 | ||
309 | if (ps->reinject == reinject) | |
310 | return; | |
311 | ||
312 | if (reinject) { | |
313 | /* The initial state is preserved while ps->reinject == 0. */ | |
314 | kvm_pit_reset_reinject(pit); | |
315 | kvm_register_irq_ack_notifier(kvm, &ps->irq_ack_notifier); | |
316 | kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); | |
317 | } else { | |
318 | kvm_unregister_irq_ack_notifier(kvm, &ps->irq_ack_notifier); | |
319 | kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier); | |
320 | } | |
321 | ||
322 | ps->reinject = reinject; | |
323 | } | |
324 | ||
09edea72 | 325 | static void create_pit_timer(struct kvm_pit *pit, u32 val, int is_period) |
7837699f | 326 | { |
09edea72 RK |
327 | struct kvm_kpit_state *ps = &pit->pit_state; |
328 | struct kvm *kvm = pit->kvm; | |
7837699f SY |
329 | s64 interval; |
330 | ||
49df6397 SR |
331 | if (!ioapic_in_kernel(kvm) || |
332 | ps->flags & KVM_PIT_FLAGS_HPET_LEGACY) | |
0924ab2c JK |
333 | return; |
334 | ||
7837699f SY |
335 | interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ); |
336 | ||
a78d9626 | 337 | pr_debug("create pit timer, interval is %llu nsec\n", interval); |
7837699f SY |
338 | |
339 | /* TODO The new value only affected after the retriggered */ | |
26ef1924 | 340 | hrtimer_cancel(&ps->timer); |
b6ddf05f | 341 | flush_kthread_work(&ps->pit->expired); |
26ef1924 | 342 | ps->period = interval; |
d3c7b77d MT |
343 | ps->is_periodic = is_period; |
344 | ||
26ef1924 | 345 | ps->timer.function = pit_timer_fn; |
09edea72 | 346 | ps->kvm = pit->kvm; |
d3c7b77d | 347 | |
09edea72 | 348 | kvm_pit_reset_reinject(pit); |
7837699f | 349 | |
9ed96e87 MT |
350 | /* |
351 | * Do not allow the guest to program periodic timers with small | |
352 | * interval, since the hrtimers are not throttled by the host | |
353 | * scheduler. | |
354 | */ | |
355 | if (ps->is_periodic) { | |
356 | s64 min_period = min_timer_period_us * 1000LL; | |
357 | ||
358 | if (ps->period < min_period) { | |
359 | pr_info_ratelimited( | |
360 | "kvm: requested %lld ns " | |
361 | "i8254 timer period limited to %lld ns\n", | |
362 | ps->period, min_period); | |
363 | ps->period = min_period; | |
364 | } | |
365 | } | |
366 | ||
26ef1924 | 367 | hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval), |
7837699f SY |
368 | HRTIMER_MODE_ABS); |
369 | } | |
370 | ||
09edea72 | 371 | static void pit_load_count(struct kvm_pit *pit, int channel, u32 val) |
7837699f | 372 | { |
09edea72 | 373 | struct kvm_kpit_state *ps = &pit->pit_state; |
7837699f | 374 | |
a78d9626 | 375 | pr_debug("load_count val is %d, channel is %d\n", val, channel); |
7837699f SY |
376 | |
377 | /* | |
ede2ccc5 MT |
378 | * The largest possible initial count is 0; this is equivalent |
379 | * to 216 for binary counting and 104 for BCD counting. | |
7837699f SY |
380 | */ |
381 | if (val == 0) | |
382 | val = 0x10000; | |
383 | ||
7837699f SY |
384 | ps->channels[channel].count = val; |
385 | ||
fd668423 MT |
386 | if (channel != 0) { |
387 | ps->channels[channel].count_load_time = ktime_get(); | |
7837699f | 388 | return; |
fd668423 | 389 | } |
7837699f SY |
390 | |
391 | /* Two types of timer | |
392 | * mode 1 is one shot, mode 2 is period, otherwise del timer */ | |
393 | switch (ps->channels[0].mode) { | |
ede2ccc5 | 394 | case 0: |
7837699f | 395 | case 1: |
ece15bab MT |
396 | /* FIXME: enhance mode 4 precision */ |
397 | case 4: | |
09edea72 | 398 | create_pit_timer(pit, val, 0); |
7837699f SY |
399 | break; |
400 | case 2: | |
f6975545 | 401 | case 3: |
09edea72 | 402 | create_pit_timer(pit, val, 1); |
7837699f SY |
403 | break; |
404 | default: | |
09edea72 | 405 | destroy_pit_timer(pit); |
7837699f SY |
406 | } |
407 | } | |
408 | ||
09edea72 RK |
409 | void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val, |
410 | int hpet_legacy_start) | |
e0f63cb9 | 411 | { |
e9f42757 | 412 | u8 saved_mode; |
b69d920f | 413 | |
09edea72 | 414 | WARN_ON_ONCE(!mutex_is_locked(&pit->pit_state.lock)); |
b69d920f | 415 | |
e9f42757 BK |
416 | if (hpet_legacy_start) { |
417 | /* save existing mode for later reenablement */ | |
e5e57e7a | 418 | WARN_ON(channel != 0); |
09edea72 RK |
419 | saved_mode = pit->pit_state.channels[0].mode; |
420 | pit->pit_state.channels[0].mode = 0xff; /* disable timer */ | |
421 | pit_load_count(pit, channel, val); | |
422 | pit->pit_state.channels[0].mode = saved_mode; | |
e9f42757 | 423 | } else { |
09edea72 | 424 | pit_load_count(pit, channel, val); |
e9f42757 | 425 | } |
e0f63cb9 SY |
426 | } |
427 | ||
d76685c4 GH |
428 | static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev) |
429 | { | |
430 | return container_of(dev, struct kvm_pit, dev); | |
431 | } | |
432 | ||
433 | static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev) | |
434 | { | |
435 | return container_of(dev, struct kvm_pit, speaker_dev); | |
436 | } | |
437 | ||
bda9020e MT |
438 | static inline int pit_in_range(gpa_t addr) |
439 | { | |
440 | return ((addr >= KVM_PIT_BASE_ADDRESS) && | |
441 | (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH)); | |
442 | } | |
443 | ||
e32edf4f NN |
444 | static int pit_ioport_write(struct kvm_vcpu *vcpu, |
445 | struct kvm_io_device *this, | |
bda9020e | 446 | gpa_t addr, int len, const void *data) |
7837699f | 447 | { |
d76685c4 | 448 | struct kvm_pit *pit = dev_to_pit(this); |
7837699f | 449 | struct kvm_kpit_state *pit_state = &pit->pit_state; |
7837699f SY |
450 | int channel, access; |
451 | struct kvm_kpit_channel_state *s; | |
452 | u32 val = *(u32 *) data; | |
bda9020e MT |
453 | if (!pit_in_range(addr)) |
454 | return -EOPNOTSUPP; | |
7837699f SY |
455 | |
456 | val &= 0xff; | |
457 | addr &= KVM_PIT_CHANNEL_MASK; | |
458 | ||
459 | mutex_lock(&pit_state->lock); | |
460 | ||
461 | if (val != 0) | |
a78d9626 JP |
462 | pr_debug("write addr is 0x%x, len is %d, val is 0x%x\n", |
463 | (unsigned int)addr, len, val); | |
7837699f SY |
464 | |
465 | if (addr == 3) { | |
466 | channel = val >> 6; | |
467 | if (channel == 3) { | |
468 | /* Read-Back Command. */ | |
469 | for (channel = 0; channel < 3; channel++) { | |
470 | s = &pit_state->channels[channel]; | |
471 | if (val & (2 << channel)) { | |
472 | if (!(val & 0x20)) | |
09edea72 | 473 | pit_latch_count(pit, channel); |
7837699f | 474 | if (!(val & 0x10)) |
09edea72 | 475 | pit_latch_status(pit, channel); |
7837699f SY |
476 | } |
477 | } | |
478 | } else { | |
479 | /* Select Counter <channel>. */ | |
480 | s = &pit_state->channels[channel]; | |
481 | access = (val >> 4) & KVM_PIT_CHANNEL_MASK; | |
482 | if (access == 0) { | |
09edea72 | 483 | pit_latch_count(pit, channel); |
7837699f SY |
484 | } else { |
485 | s->rw_mode = access; | |
486 | s->read_state = access; | |
487 | s->write_state = access; | |
488 | s->mode = (val >> 1) & 7; | |
489 | if (s->mode > 5) | |
490 | s->mode -= 4; | |
491 | s->bcd = val & 1; | |
492 | } | |
493 | } | |
494 | } else { | |
495 | /* Write Count. */ | |
496 | s = &pit_state->channels[addr]; | |
497 | switch (s->write_state) { | |
498 | default: | |
499 | case RW_STATE_LSB: | |
09edea72 | 500 | pit_load_count(pit, addr, val); |
7837699f SY |
501 | break; |
502 | case RW_STATE_MSB: | |
09edea72 | 503 | pit_load_count(pit, addr, val << 8); |
7837699f SY |
504 | break; |
505 | case RW_STATE_WORD0: | |
506 | s->write_latch = val; | |
507 | s->write_state = RW_STATE_WORD1; | |
508 | break; | |
509 | case RW_STATE_WORD1: | |
09edea72 | 510 | pit_load_count(pit, addr, s->write_latch | (val << 8)); |
7837699f SY |
511 | s->write_state = RW_STATE_WORD0; |
512 | break; | |
513 | } | |
514 | } | |
515 | ||
516 | mutex_unlock(&pit_state->lock); | |
bda9020e | 517 | return 0; |
7837699f SY |
518 | } |
519 | ||
e32edf4f NN |
520 | static int pit_ioport_read(struct kvm_vcpu *vcpu, |
521 | struct kvm_io_device *this, | |
bda9020e | 522 | gpa_t addr, int len, void *data) |
7837699f | 523 | { |
d76685c4 | 524 | struct kvm_pit *pit = dev_to_pit(this); |
7837699f | 525 | struct kvm_kpit_state *pit_state = &pit->pit_state; |
7837699f SY |
526 | int ret, count; |
527 | struct kvm_kpit_channel_state *s; | |
bda9020e MT |
528 | if (!pit_in_range(addr)) |
529 | return -EOPNOTSUPP; | |
7837699f SY |
530 | |
531 | addr &= KVM_PIT_CHANNEL_MASK; | |
ee73f656 MT |
532 | if (addr == 3) |
533 | return 0; | |
534 | ||
7837699f SY |
535 | s = &pit_state->channels[addr]; |
536 | ||
537 | mutex_lock(&pit_state->lock); | |
538 | ||
539 | if (s->status_latched) { | |
540 | s->status_latched = 0; | |
541 | ret = s->status; | |
542 | } else if (s->count_latched) { | |
543 | switch (s->count_latched) { | |
544 | default: | |
545 | case RW_STATE_LSB: | |
546 | ret = s->latched_count & 0xff; | |
547 | s->count_latched = 0; | |
548 | break; | |
549 | case RW_STATE_MSB: | |
550 | ret = s->latched_count >> 8; | |
551 | s->count_latched = 0; | |
552 | break; | |
553 | case RW_STATE_WORD0: | |
554 | ret = s->latched_count & 0xff; | |
555 | s->count_latched = RW_STATE_MSB; | |
556 | break; | |
557 | } | |
558 | } else { | |
559 | switch (s->read_state) { | |
560 | default: | |
561 | case RW_STATE_LSB: | |
09edea72 | 562 | count = pit_get_count(pit, addr); |
7837699f SY |
563 | ret = count & 0xff; |
564 | break; | |
565 | case RW_STATE_MSB: | |
09edea72 | 566 | count = pit_get_count(pit, addr); |
7837699f SY |
567 | ret = (count >> 8) & 0xff; |
568 | break; | |
569 | case RW_STATE_WORD0: | |
09edea72 | 570 | count = pit_get_count(pit, addr); |
7837699f SY |
571 | ret = count & 0xff; |
572 | s->read_state = RW_STATE_WORD1; | |
573 | break; | |
574 | case RW_STATE_WORD1: | |
09edea72 | 575 | count = pit_get_count(pit, addr); |
7837699f SY |
576 | ret = (count >> 8) & 0xff; |
577 | s->read_state = RW_STATE_WORD0; | |
578 | break; | |
579 | } | |
580 | } | |
581 | ||
582 | if (len > sizeof(ret)) | |
583 | len = sizeof(ret); | |
584 | memcpy(data, (char *)&ret, len); | |
585 | ||
586 | mutex_unlock(&pit_state->lock); | |
bda9020e | 587 | return 0; |
7837699f SY |
588 | } |
589 | ||
e32edf4f NN |
590 | static int speaker_ioport_write(struct kvm_vcpu *vcpu, |
591 | struct kvm_io_device *this, | |
bda9020e | 592 | gpa_t addr, int len, const void *data) |
7837699f | 593 | { |
d76685c4 | 594 | struct kvm_pit *pit = speaker_to_pit(this); |
7837699f | 595 | struct kvm_kpit_state *pit_state = &pit->pit_state; |
7837699f | 596 | u32 val = *(u32 *) data; |
bda9020e MT |
597 | if (addr != KVM_SPEAKER_BASE_ADDRESS) |
598 | return -EOPNOTSUPP; | |
7837699f SY |
599 | |
600 | mutex_lock(&pit_state->lock); | |
601 | pit_state->speaker_data_on = (val >> 1) & 1; | |
09edea72 | 602 | pit_set_gate(pit, 2, val & 1); |
7837699f | 603 | mutex_unlock(&pit_state->lock); |
bda9020e | 604 | return 0; |
7837699f SY |
605 | } |
606 | ||
e32edf4f NN |
607 | static int speaker_ioport_read(struct kvm_vcpu *vcpu, |
608 | struct kvm_io_device *this, | |
609 | gpa_t addr, int len, void *data) | |
7837699f | 610 | { |
d76685c4 | 611 | struct kvm_pit *pit = speaker_to_pit(this); |
7837699f | 612 | struct kvm_kpit_state *pit_state = &pit->pit_state; |
7837699f SY |
613 | unsigned int refresh_clock; |
614 | int ret; | |
bda9020e MT |
615 | if (addr != KVM_SPEAKER_BASE_ADDRESS) |
616 | return -EOPNOTSUPP; | |
7837699f SY |
617 | |
618 | /* Refresh clock toggles at about 15us. We approximate as 2^14ns. */ | |
619 | refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1; | |
620 | ||
621 | mutex_lock(&pit_state->lock); | |
09edea72 RK |
622 | ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(pit, 2) | |
623 | (pit_get_out(pit, 2) << 5) | (refresh_clock << 4)); | |
7837699f SY |
624 | if (len > sizeof(ret)) |
625 | len = sizeof(ret); | |
626 | memcpy(data, (char *)&ret, len); | |
627 | mutex_unlock(&pit_state->lock); | |
bda9020e | 628 | return 0; |
7837699f SY |
629 | } |
630 | ||
b39c90b6 | 631 | static void kvm_pit_reset(struct kvm_pit *pit) |
7837699f SY |
632 | { |
633 | int i; | |
308b0f23 SY |
634 | struct kvm_kpit_channel_state *c; |
635 | ||
e9f42757 | 636 | pit->pit_state.flags = 0; |
308b0f23 SY |
637 | for (i = 0; i < 3; i++) { |
638 | c = &pit->pit_state.channels[i]; | |
639 | c->mode = 0xff; | |
640 | c->gate = (i != 2); | |
09edea72 | 641 | pit_load_count(pit, i, 0); |
308b0f23 | 642 | } |
308b0f23 | 643 | |
fd700a00 | 644 | kvm_pit_reset_reinject(pit); |
308b0f23 SY |
645 | } |
646 | ||
4780c659 AK |
647 | static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) |
648 | { | |
649 | struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier); | |
650 | ||
fd700a00 RK |
651 | if (!mask) |
652 | kvm_pit_reset_reinject(pit); | |
4780c659 AK |
653 | } |
654 | ||
d76685c4 GH |
655 | static const struct kvm_io_device_ops pit_dev_ops = { |
656 | .read = pit_ioport_read, | |
657 | .write = pit_ioport_write, | |
d76685c4 GH |
658 | }; |
659 | ||
660 | static const struct kvm_io_device_ops speaker_dev_ops = { | |
661 | .read = speaker_ioport_read, | |
662 | .write = speaker_ioport_write, | |
d76685c4 GH |
663 | }; |
664 | ||
79fac95e | 665 | /* Caller must hold slots_lock */ |
c5ff41ce | 666 | struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) |
308b0f23 | 667 | { |
7837699f SY |
668 | struct kvm_pit *pit; |
669 | struct kvm_kpit_state *pit_state; | |
b6ddf05f JK |
670 | struct pid *pid; |
671 | pid_t pid_nr; | |
090b7aff | 672 | int ret; |
7837699f SY |
673 | |
674 | pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL); | |
675 | if (!pit) | |
676 | return NULL; | |
677 | ||
5550af4d | 678 | pit->irq_source_id = kvm_request_irq_source_id(kvm); |
10d24821 RK |
679 | if (pit->irq_source_id < 0) |
680 | goto fail_request; | |
5550af4d | 681 | |
7837699f | 682 | mutex_init(&pit->pit_state.lock); |
33572ac0 | 683 | |
b6ddf05f JK |
684 | pid = get_pid(task_tgid(current)); |
685 | pid_nr = pid_vnr(pid); | |
686 | put_pid(pid); | |
687 | ||
688 | init_kthread_worker(&pit->worker); | |
689 | pit->worker_task = kthread_run(kthread_worker_fn, &pit->worker, | |
690 | "kvm-pit/%d", pid_nr); | |
10d24821 RK |
691 | if (IS_ERR(pit->worker_task)) |
692 | goto fail_kthread; | |
693 | ||
b6ddf05f | 694 | init_kthread_work(&pit->expired, pit_do_work); |
7837699f | 695 | |
7837699f SY |
696 | pit->kvm = kvm; |
697 | ||
698 | pit_state = &pit->pit_state; | |
699 | pit_state->pit = pit; | |
26ef1924 | 700 | hrtimer_init(&pit_state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); |
71474e2f | 701 | |
3cf57fed MT |
702 | pit_state->irq_ack_notifier.gsi = 0; |
703 | pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq; | |
71474e2f | 704 | pit->mask_notifier.func = pit_mask_notifer; |
7837699f | 705 | |
308b0f23 | 706 | kvm_pit_reset(pit); |
7837699f | 707 | |
71474e2f | 708 | kvm_pit_set_reinject(pit, true); |
4780c659 | 709 | |
6b66ac1a | 710 | kvm_iodevice_init(&pit->dev, &pit_dev_ops); |
743eeb0b SL |
711 | ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS, |
712 | KVM_PIT_MEM_LENGTH, &pit->dev); | |
090b7aff | 713 | if (ret < 0) |
10d24821 | 714 | goto fail_register_pit; |
6b66ac1a GH |
715 | |
716 | if (flags & KVM_PIT_SPEAKER_DUMMY) { | |
717 | kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); | |
e93f8a0f | 718 | ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, |
743eeb0b SL |
719 | KVM_SPEAKER_BASE_ADDRESS, 4, |
720 | &pit->speaker_dev); | |
090b7aff | 721 | if (ret < 0) |
10d24821 | 722 | goto fail_register_speaker; |
6b66ac1a GH |
723 | } |
724 | ||
7837699f | 725 | return pit; |
090b7aff | 726 | |
10d24821 | 727 | fail_register_speaker: |
e93f8a0f | 728 | kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); |
10d24821 | 729 | fail_register_pit: |
71474e2f | 730 | kvm_pit_set_reinject(pit, false); |
b6ddf05f | 731 | kthread_stop(pit->worker_task); |
10d24821 RK |
732 | fail_kthread: |
733 | kvm_free_irq_source_id(kvm, pit->irq_source_id); | |
734 | fail_request: | |
090b7aff GH |
735 | kfree(pit); |
736 | return NULL; | |
7837699f SY |
737 | } |
738 | ||
739 | void kvm_free_pit(struct kvm *kvm) | |
740 | { | |
741 | struct hrtimer *timer; | |
742 | ||
743 | if (kvm->arch.vpit) { | |
aea924f6 XG |
744 | kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &kvm->arch.vpit->dev); |
745 | kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, | |
746 | &kvm->arch.vpit->speaker_dev); | |
71474e2f | 747 | kvm_pit_set_reinject(kvm->arch.vpit, false); |
26ef1924 | 748 | timer = &kvm->arch.vpit->pit_state.timer; |
7837699f | 749 | hrtimer_cancel(timer); |
b6ddf05f JK |
750 | flush_kthread_work(&kvm->arch.vpit->expired); |
751 | kthread_stop(kvm->arch.vpit->worker_task); | |
5550af4d | 752 | kvm_free_irq_source_id(kvm, kvm->arch.vpit->irq_source_id); |
7837699f SY |
753 | kfree(kvm->arch.vpit); |
754 | } | |
755 | } |