blob: 2491bf82e30cafa05f5fc10721fd4a13993c6477 [file] [log] [blame]
Terje Bergstrom7ede0b02013-03-22 16:34:02 +02001/*
2 * Tegra host1x Interrupt Management
3 *
4 * Copyright (c) 2010-2013, NVIDIA Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18
19#include <linux/clk.h>
20#include <linux/interrupt.h>
21#include <linux/slab.h>
22#include <linux/irq.h>
23
Terje Bergstrom65793242013-03-22 16:34:03 +020024#include <trace/events/host1x.h>
25#include "channel.h"
Terje Bergstrom7ede0b02013-03-22 16:34:02 +020026#include "dev.h"
27#include "intr.h"
28
29/* Wait list management */
30
31enum waitlist_state {
32 WLS_PENDING,
33 WLS_REMOVED,
34 WLS_CANCELLED,
35 WLS_HANDLED
36};
37
38static void waiter_release(struct kref *kref)
39{
40 kfree(container_of(kref, struct host1x_waitlist, refcount));
41}
42
43/*
44 * add a waiter to a waiter queue, sorted by threshold
45 * returns true if it was added at the head of the queue
46 */
47static bool add_waiter_to_queue(struct host1x_waitlist *waiter,
48 struct list_head *queue)
49{
50 struct host1x_waitlist *pos;
51 u32 thresh = waiter->thresh;
52
53 list_for_each_entry_reverse(pos, queue, list)
54 if ((s32)(pos->thresh - thresh) <= 0) {
55 list_add(&waiter->list, &pos->list);
56 return false;
57 }
58
59 list_add(&waiter->list, queue);
60 return true;
61}
62
63/*
64 * run through a waiter queue for a single sync point ID
65 * and gather all completed waiters into lists by actions
66 */
67static void remove_completed_waiters(struct list_head *head, u32 sync,
68 struct list_head completed[HOST1X_INTR_ACTION_COUNT])
69{
70 struct list_head *dest;
Terje Bergstrom65793242013-03-22 16:34:03 +020071 struct host1x_waitlist *waiter, *next, *prev;
Terje Bergstrom7ede0b02013-03-22 16:34:02 +020072
73 list_for_each_entry_safe(waiter, next, head, list) {
74 if ((s32)(waiter->thresh - sync) > 0)
75 break;
76
77 dest = completed + waiter->action;
78
Terje Bergstrom65793242013-03-22 16:34:03 +020079 /* consolidate submit cleanups */
80 if (waiter->action == HOST1X_INTR_ACTION_SUBMIT_COMPLETE &&
81 !list_empty(dest)) {
82 prev = list_entry(dest->prev,
83 struct host1x_waitlist, list);
84 if (prev->data == waiter->data) {
85 prev->count++;
86 dest = NULL;
87 }
88 }
89
Terje Bergstrom7ede0b02013-03-22 16:34:02 +020090 /* PENDING->REMOVED or CANCELLED->HANDLED */
91 if (atomic_inc_return(&waiter->state) == WLS_HANDLED || !dest) {
92 list_del(&waiter->list);
93 kref_put(&waiter->refcount, waiter_release);
94 } else
95 list_move_tail(&waiter->list, dest);
96 }
97}
98
99static void reset_threshold_interrupt(struct host1x *host,
100 struct list_head *head,
101 unsigned int id)
102{
103 u32 thresh =
104 list_first_entry(head, struct host1x_waitlist, list)->thresh;
105
106 host1x_hw_intr_set_syncpt_threshold(host, id, thresh);
107 host1x_hw_intr_enable_syncpt_intr(host, id);
108}
109
Terje Bergstrom65793242013-03-22 16:34:03 +0200110static void action_submit_complete(struct host1x_waitlist *waiter)
111{
112 struct host1x_channel *channel = waiter->data;
113
114 host1x_cdma_update(&channel->cdma);
115
116 /* Add nr_completed to trace */
117 trace_host1x_channel_submit_complete(dev_name(channel->dev),
118 waiter->count, waiter->thresh);
119
120}
121
Terje Bergstrom7ede0b02013-03-22 16:34:02 +0200122static void action_wakeup(struct host1x_waitlist *waiter)
123{
124 wait_queue_head_t *wq = waiter->data;
125 wake_up(wq);
126}
127
128static void action_wakeup_interruptible(struct host1x_waitlist *waiter)
129{
130 wait_queue_head_t *wq = waiter->data;
131 wake_up_interruptible(wq);
132}
133
134typedef void (*action_handler)(struct host1x_waitlist *waiter);
135
136static action_handler action_handlers[HOST1X_INTR_ACTION_COUNT] = {
Terje Bergstrom65793242013-03-22 16:34:03 +0200137 action_submit_complete,
Terje Bergstrom7ede0b02013-03-22 16:34:02 +0200138 action_wakeup,
139 action_wakeup_interruptible,
140};
141
142static void run_handlers(struct list_head completed[HOST1X_INTR_ACTION_COUNT])
143{
144 struct list_head *head = completed;
145 int i;
146
147 for (i = 0; i < HOST1X_INTR_ACTION_COUNT; ++i, ++head) {
148 action_handler handler = action_handlers[i];
149 struct host1x_waitlist *waiter, *next;
150
151 list_for_each_entry_safe(waiter, next, head, list) {
152 list_del(&waiter->list);
153 handler(waiter);
154 WARN_ON(atomic_xchg(&waiter->state, WLS_HANDLED) !=
155 WLS_REMOVED);
156 kref_put(&waiter->refcount, waiter_release);
157 }
158 }
159}
160
161/*
162 * Remove & handle all waiters that have completed for the given syncpt
163 */
164static int process_wait_list(struct host1x *host,
165 struct host1x_syncpt *syncpt,
166 u32 threshold)
167{
168 struct list_head completed[HOST1X_INTR_ACTION_COUNT];
169 unsigned int i;
170 int empty;
171
172 for (i = 0; i < HOST1X_INTR_ACTION_COUNT; ++i)
173 INIT_LIST_HEAD(completed + i);
174
175 spin_lock(&syncpt->intr.lock);
176
177 remove_completed_waiters(&syncpt->intr.wait_head, threshold,
178 completed);
179
180 empty = list_empty(&syncpt->intr.wait_head);
181 if (empty)
182 host1x_hw_intr_disable_syncpt_intr(host, syncpt->id);
183 else
184 reset_threshold_interrupt(host, &syncpt->intr.wait_head,
185 syncpt->id);
186
187 spin_unlock(&syncpt->intr.lock);
188
189 run_handlers(completed);
190
191 return empty;
192}
193
194/*
195 * Sync point threshold interrupt service thread function
196 * Handles sync point threshold triggers, in thread context
197 */
198
199static void syncpt_thresh_work(struct work_struct *work)
200{
201 struct host1x_syncpt_intr *syncpt_intr =
202 container_of(work, struct host1x_syncpt_intr, work);
203 struct host1x_syncpt *syncpt =
204 container_of(syncpt_intr, struct host1x_syncpt, intr);
205 unsigned int id = syncpt->id;
206 struct host1x *host = syncpt->host;
207
208 (void)process_wait_list(host, syncpt,
209 host1x_syncpt_load(host->syncpt + id));
210}
211
212int host1x_intr_add_action(struct host1x *host, u32 id, u32 thresh,
213 enum host1x_intr_action action, void *data,
214 struct host1x_waitlist *waiter, void **ref)
215{
216 struct host1x_syncpt *syncpt;
217 int queue_was_empty;
218
219 if (waiter == NULL) {
220 pr_warn("%s: NULL waiter\n", __func__);
221 return -EINVAL;
222 }
223
224 /* initialize a new waiter */
225 INIT_LIST_HEAD(&waiter->list);
226 kref_init(&waiter->refcount);
227 if (ref)
228 kref_get(&waiter->refcount);
229 waiter->thresh = thresh;
230 waiter->action = action;
231 atomic_set(&waiter->state, WLS_PENDING);
232 waiter->data = data;
233 waiter->count = 1;
234
235 syncpt = host->syncpt + id;
236
237 spin_lock(&syncpt->intr.lock);
238
239 queue_was_empty = list_empty(&syncpt->intr.wait_head);
240
241 if (add_waiter_to_queue(waiter, &syncpt->intr.wait_head)) {
242 /* added at head of list - new threshold value */
243 host1x_hw_intr_set_syncpt_threshold(host, id, thresh);
244
245 /* added as first waiter - enable interrupt */
246 if (queue_was_empty)
247 host1x_hw_intr_enable_syncpt_intr(host, id);
248 }
249
250 spin_unlock(&syncpt->intr.lock);
251
252 if (ref)
253 *ref = waiter;
254 return 0;
255}
256
257void host1x_intr_put_ref(struct host1x *host, u32 id, void *ref)
258{
259 struct host1x_waitlist *waiter = ref;
260 struct host1x_syncpt *syncpt;
261
262 while (atomic_cmpxchg(&waiter->state, WLS_PENDING, WLS_CANCELLED) ==
263 WLS_REMOVED)
264 schedule();
265
266 syncpt = host->syncpt + id;
267 (void)process_wait_list(host, syncpt,
268 host1x_syncpt_load(host->syncpt + id));
269
270 kref_put(&waiter->refcount, waiter_release);
271}
272
273int host1x_intr_init(struct host1x *host, unsigned int irq_sync)
274{
275 unsigned int id;
276 u32 nb_pts = host1x_syncpt_nb_pts(host);
277
278 mutex_init(&host->intr_mutex);
279 host->intr_syncpt_irq = irq_sync;
280 host->intr_wq = create_workqueue("host_syncpt");
281 if (!host->intr_wq)
282 return -ENOMEM;
283
284 for (id = 0; id < nb_pts; ++id) {
285 struct host1x_syncpt *syncpt = host->syncpt + id;
286
287 spin_lock_init(&syncpt->intr.lock);
288 INIT_LIST_HEAD(&syncpt->intr.wait_head);
289 snprintf(syncpt->intr.thresh_irq_name,
290 sizeof(syncpt->intr.thresh_irq_name),
291 "host1x_sp_%02d", id);
292 }
293
294 host1x_intr_start(host);
295
296 return 0;
297}
298
299void host1x_intr_deinit(struct host1x *host)
300{
301 host1x_intr_stop(host);
302 destroy_workqueue(host->intr_wq);
303}
304
305void host1x_intr_start(struct host1x *host)
306{
307 u32 hz = clk_get_rate(host->clk);
308 int err;
309
310 mutex_lock(&host->intr_mutex);
311 err = host1x_hw_intr_init_host_sync(host, DIV_ROUND_UP(hz, 1000000),
312 syncpt_thresh_work);
313 if (err) {
314 mutex_unlock(&host->intr_mutex);
315 return;
316 }
317 mutex_unlock(&host->intr_mutex);
318}
319
320void host1x_intr_stop(struct host1x *host)
321{
322 unsigned int id;
323 struct host1x_syncpt *syncpt = host->syncpt;
324 u32 nb_pts = host1x_syncpt_nb_pts(host);
325
326 mutex_lock(&host->intr_mutex);
327
328 host1x_hw_intr_disable_all_syncpt_intrs(host);
329
330 for (id = 0; id < nb_pts; ++id) {
331 struct host1x_waitlist *waiter, *next;
332
333 list_for_each_entry_safe(waiter, next,
334 &syncpt[id].intr.wait_head, list) {
335 if (atomic_cmpxchg(&waiter->state,
336 WLS_CANCELLED, WLS_HANDLED) == WLS_CANCELLED) {
337 list_del(&waiter->list);
338 kref_put(&waiter->refcount, waiter_release);
339 }
340 }
341
342 if (!list_empty(&syncpt[id].intr.wait_head)) {
343 /* output diagnostics */
344 mutex_unlock(&host->intr_mutex);
345 pr_warn("%s cannot stop syncpt intr id=%d\n",
346 __func__, id);
347 return;
348 }
349 }
350
351 host1x_hw_intr_free_syncpt_irq(host);
352
353 mutex_unlock(&host->intr_mutex);
354}