1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (c) 2018 MediaTek Inc.
4
5 #include <linux/bitops.h>
6 #include <linux/clk.h>
7 #include <linux/clk-provider.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/errno.h>
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/iopoll.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/mailbox_controller.h>
17 #include <linux/mailbox/mtk-cmdq-mailbox.h>
18 #include <linux/of_device.h>
19
20 #define CMDQ_OP_CODE_MASK (0xff << CMDQ_OP_CODE_SHIFT)
21 #define CMDQ_NUM_CMD(t) (t->cmd_buf_size / CMDQ_INST_SIZE)
22
23 #define CMDQ_CURR_IRQ_STATUS 0x10
24 #define CMDQ_SYNC_TOKEN_UPDATE 0x68
25 #define CMDQ_THR_SLOT_CYCLES 0x30
26 #define CMDQ_THR_BASE 0x100
27 #define CMDQ_THR_SIZE 0x80
28 #define CMDQ_THR_WARM_RESET 0x00
29 #define CMDQ_THR_ENABLE_TASK 0x04
30 #define CMDQ_THR_SUSPEND_TASK 0x08
31 #define CMDQ_THR_CURR_STATUS 0x0c
32 #define CMDQ_THR_IRQ_STATUS 0x10
33 #define CMDQ_THR_IRQ_ENABLE 0x14
34 #define CMDQ_THR_CURR_ADDR 0x20
35 #define CMDQ_THR_END_ADDR 0x24
36 #define CMDQ_THR_WAIT_TOKEN 0x30
37 #define CMDQ_THR_PRIORITY 0x40
38
39 #define CMDQ_THR_ACTIVE_SLOT_CYCLES 0x3200
40 #define CMDQ_THR_ENABLED 0x1
41 #define CMDQ_THR_DISABLED 0x0
42 #define CMDQ_THR_SUSPEND 0x1
43 #define CMDQ_THR_RESUME 0x0
44 #define CMDQ_THR_STATUS_SUSPENDED BIT(1)
45 #define CMDQ_THR_DO_WARM_RESET BIT(0)
46 #define CMDQ_THR_IRQ_DONE 0x1
47 #define CMDQ_THR_IRQ_ERROR 0x12
48 #define CMDQ_THR_IRQ_EN (CMDQ_THR_IRQ_ERROR | CMDQ_THR_IRQ_DONE)
49 #define CMDQ_THR_IS_WAITING BIT(31)
50
51 #define CMDQ_JUMP_BY_OFFSET 0x10000000
52 #define CMDQ_JUMP_BY_PA 0x10000001
53
54 struct cmdq_thread {
55 struct mbox_chan *chan;
56 void __iomem *base;
57 struct list_head task_busy_list;
58 u32 priority;
59 bool atomic_exec;
60 };
61
62 struct cmdq_task {
63 struct cmdq *cmdq;
64 struct list_head list_entry;
65 dma_addr_t pa_base;
66 struct cmdq_thread *thread;
67 struct cmdq_pkt *pkt; /* the packet sent from mailbox client */
68 };
69
70 struct cmdq {
71 struct mbox_controller mbox;
72 void __iomem *base;
73 u32 irq;
74 u32 thread_nr;
75 u32 irq_mask;
76 struct cmdq_thread *thread;
77 struct clk *clock;
78 bool suspended;
79 };
80
cmdq_thread_suspend(struct cmdq * cmdq,struct cmdq_thread * thread)81 static int cmdq_thread_suspend(struct cmdq *cmdq, struct cmdq_thread *thread)
82 {
83 u32 status;
84
85 writel(CMDQ_THR_SUSPEND, thread->base + CMDQ_THR_SUSPEND_TASK);
86
87 /* If already disabled, treat as suspended successful. */
88 if (!(readl(thread->base + CMDQ_THR_ENABLE_TASK) & CMDQ_THR_ENABLED))
89 return 0;
90
91 if (readl_poll_timeout_atomic(thread->base + CMDQ_THR_CURR_STATUS,
92 status, status & CMDQ_THR_STATUS_SUSPENDED, 0, 10)) {
93 dev_err(cmdq->mbox.dev, "suspend GCE thread 0x%x failed\n",
94 (u32)(thread->base - cmdq->base));
95 return -EFAULT;
96 }
97
98 return 0;
99 }
100
cmdq_thread_resume(struct cmdq_thread * thread)101 static void cmdq_thread_resume(struct cmdq_thread *thread)
102 {
103 writel(CMDQ_THR_RESUME, thread->base + CMDQ_THR_SUSPEND_TASK);
104 }
105
cmdq_init(struct cmdq * cmdq)106 static void cmdq_init(struct cmdq *cmdq)
107 {
108 int i;
109
110 WARN_ON(clk_enable(cmdq->clock) < 0);
111 writel(CMDQ_THR_ACTIVE_SLOT_CYCLES, cmdq->base + CMDQ_THR_SLOT_CYCLES);
112 for (i = 0; i <= CMDQ_MAX_EVENT; i++)
113 writel(i, cmdq->base + CMDQ_SYNC_TOKEN_UPDATE);
114 clk_disable(cmdq->clock);
115 }
116
cmdq_thread_reset(struct cmdq * cmdq,struct cmdq_thread * thread)117 static int cmdq_thread_reset(struct cmdq *cmdq, struct cmdq_thread *thread)
118 {
119 u32 warm_reset;
120
121 writel(CMDQ_THR_DO_WARM_RESET, thread->base + CMDQ_THR_WARM_RESET);
122 if (readl_poll_timeout_atomic(thread->base + CMDQ_THR_WARM_RESET,
123 warm_reset, !(warm_reset & CMDQ_THR_DO_WARM_RESET),
124 0, 10)) {
125 dev_err(cmdq->mbox.dev, "reset GCE thread 0x%x failed\n",
126 (u32)(thread->base - cmdq->base));
127 return -EFAULT;
128 }
129
130 return 0;
131 }
132
cmdq_thread_disable(struct cmdq * cmdq,struct cmdq_thread * thread)133 static void cmdq_thread_disable(struct cmdq *cmdq, struct cmdq_thread *thread)
134 {
135 cmdq_thread_reset(cmdq, thread);
136 writel(CMDQ_THR_DISABLED, thread->base + CMDQ_THR_ENABLE_TASK);
137 }
138
139 /* notify GCE to re-fetch commands by setting GCE thread PC */
cmdq_thread_invalidate_fetched_data(struct cmdq_thread * thread)140 static void cmdq_thread_invalidate_fetched_data(struct cmdq_thread *thread)
141 {
142 writel(readl(thread->base + CMDQ_THR_CURR_ADDR),
143 thread->base + CMDQ_THR_CURR_ADDR);
144 }
145
cmdq_task_insert_into_thread(struct cmdq_task * task)146 static void cmdq_task_insert_into_thread(struct cmdq_task *task)
147 {
148 struct device *dev = task->cmdq->mbox.dev;
149 struct cmdq_thread *thread = task->thread;
150 struct cmdq_task *prev_task = list_last_entry(
151 &thread->task_busy_list, typeof(*task), list_entry);
152 u64 *prev_task_base = prev_task->pkt->va_base;
153
154 /* let previous task jump to this task */
155 dma_sync_single_for_cpu(dev, prev_task->pa_base,
156 prev_task->pkt->cmd_buf_size, DMA_TO_DEVICE);
157 prev_task_base[CMDQ_NUM_CMD(prev_task->pkt) - 1] =
158 (u64)CMDQ_JUMP_BY_PA << 32 | task->pa_base;
159 dma_sync_single_for_device(dev, prev_task->pa_base,
160 prev_task->pkt->cmd_buf_size, DMA_TO_DEVICE);
161
162 cmdq_thread_invalidate_fetched_data(thread);
163 }
164
cmdq_command_is_wfe(u64 cmd)165 static bool cmdq_command_is_wfe(u64 cmd)
166 {
167 u64 wfe_option = CMDQ_WFE_UPDATE | CMDQ_WFE_WAIT | CMDQ_WFE_WAIT_VALUE;
168 u64 wfe_op = (u64)(CMDQ_CODE_WFE << CMDQ_OP_CODE_SHIFT) << 32;
169 u64 wfe_mask = (u64)CMDQ_OP_CODE_MASK << 32 | 0xffffffff;
170
171 return ((cmd & wfe_mask) == (wfe_op | wfe_option));
172 }
173
174 /* we assume tasks in the same display GCE thread are waiting the same event. */
cmdq_task_remove_wfe(struct cmdq_task * task)175 static void cmdq_task_remove_wfe(struct cmdq_task *task)
176 {
177 struct device *dev = task->cmdq->mbox.dev;
178 u64 *base = task->pkt->va_base;
179 int i;
180
181 dma_sync_single_for_cpu(dev, task->pa_base, task->pkt->cmd_buf_size,
182 DMA_TO_DEVICE);
183 for (i = 0; i < CMDQ_NUM_CMD(task->pkt); i++)
184 if (cmdq_command_is_wfe(base[i]))
185 base[i] = (u64)CMDQ_JUMP_BY_OFFSET << 32 |
186 CMDQ_JUMP_PASS;
187 dma_sync_single_for_device(dev, task->pa_base, task->pkt->cmd_buf_size,
188 DMA_TO_DEVICE);
189 }
190
cmdq_thread_is_in_wfe(struct cmdq_thread * thread)191 static bool cmdq_thread_is_in_wfe(struct cmdq_thread *thread)
192 {
193 return readl(thread->base + CMDQ_THR_WAIT_TOKEN) & CMDQ_THR_IS_WAITING;
194 }
195
cmdq_thread_wait_end(struct cmdq_thread * thread,unsigned long end_pa)196 static void cmdq_thread_wait_end(struct cmdq_thread *thread,
197 unsigned long end_pa)
198 {
199 struct device *dev = thread->chan->mbox->dev;
200 unsigned long curr_pa;
201
202 if (readl_poll_timeout_atomic(thread->base + CMDQ_THR_CURR_ADDR,
203 curr_pa, curr_pa == end_pa, 1, 20))
204 dev_err(dev, "GCE thread cannot run to end.\n");
205 }
206
cmdq_task_exec_done(struct cmdq_task * task,enum cmdq_cb_status sta)207 static void cmdq_task_exec_done(struct cmdq_task *task, enum cmdq_cb_status sta)
208 {
209 struct cmdq_task_cb *cb = &task->pkt->async_cb;
210 struct cmdq_cb_data data;
211
212 WARN_ON(cb->cb == (cmdq_async_flush_cb)NULL);
213 data.sta = sta;
214 data.data = cb->data;
215 cb->cb(data);
216
217 list_del(&task->list_entry);
218 }
219
cmdq_task_handle_error(struct cmdq_task * task)220 static void cmdq_task_handle_error(struct cmdq_task *task)
221 {
222 struct cmdq_thread *thread = task->thread;
223 struct cmdq_task *next_task;
224
225 dev_err(task->cmdq->mbox.dev, "task 0x%p error\n", task);
226 WARN_ON(cmdq_thread_suspend(task->cmdq, thread) < 0);
227 next_task = list_first_entry_or_null(&thread->task_busy_list,
228 struct cmdq_task, list_entry);
229 if (next_task)
230 writel(next_task->pa_base, thread->base + CMDQ_THR_CURR_ADDR);
231 cmdq_thread_resume(thread);
232 }
233
cmdq_thread_irq_handler(struct cmdq * cmdq,struct cmdq_thread * thread)234 static void cmdq_thread_irq_handler(struct cmdq *cmdq,
235 struct cmdq_thread *thread)
236 {
237 struct cmdq_task *task, *tmp, *curr_task = NULL;
238 u32 curr_pa, irq_flag, task_end_pa;
239 bool err;
240
241 irq_flag = readl(thread->base + CMDQ_THR_IRQ_STATUS);
242 writel(~irq_flag, thread->base + CMDQ_THR_IRQ_STATUS);
243
244 /*
245 * When ISR call this function, another CPU core could run
246 * "release task" right before we acquire the spin lock, and thus
247 * reset / disable this GCE thread, so we need to check the enable
248 * bit of this GCE thread.
249 */
250 if (!(readl(thread->base + CMDQ_THR_ENABLE_TASK) & CMDQ_THR_ENABLED))
251 return;
252
253 if (irq_flag & CMDQ_THR_IRQ_ERROR)
254 err = true;
255 else if (irq_flag & CMDQ_THR_IRQ_DONE)
256 err = false;
257 else
258 return;
259
260 curr_pa = readl(thread->base + CMDQ_THR_CURR_ADDR);
261
262 list_for_each_entry_safe(task, tmp, &thread->task_busy_list,
263 list_entry) {
264 task_end_pa = task->pa_base + task->pkt->cmd_buf_size;
265 if (curr_pa >= task->pa_base && curr_pa < task_end_pa)
266 curr_task = task;
267
268 if (!curr_task || curr_pa == task_end_pa - CMDQ_INST_SIZE) {
269 cmdq_task_exec_done(task, CMDQ_CB_NORMAL);
270 kfree(task);
271 } else if (err) {
272 cmdq_task_exec_done(task, CMDQ_CB_ERROR);
273 cmdq_task_handle_error(curr_task);
274 kfree(task);
275 }
276
277 if (curr_task)
278 break;
279 }
280
281 if (list_empty(&thread->task_busy_list)) {
282 cmdq_thread_disable(cmdq, thread);
283 clk_disable(cmdq->clock);
284 }
285 }
286
cmdq_irq_handler(int irq,void * dev)287 static irqreturn_t cmdq_irq_handler(int irq, void *dev)
288 {
289 struct cmdq *cmdq = dev;
290 unsigned long irq_status, flags = 0L;
291 int bit;
292
293 irq_status = readl(cmdq->base + CMDQ_CURR_IRQ_STATUS) & cmdq->irq_mask;
294 if (!(irq_status ^ cmdq->irq_mask))
295 return IRQ_NONE;
296
297 for_each_clear_bit(bit, &irq_status, cmdq->thread_nr) {
298 struct cmdq_thread *thread = &cmdq->thread[bit];
299
300 spin_lock_irqsave(&thread->chan->lock, flags);
301 cmdq_thread_irq_handler(cmdq, thread);
302 spin_unlock_irqrestore(&thread->chan->lock, flags);
303 }
304
305 return IRQ_HANDLED;
306 }
307
cmdq_suspend(struct device * dev)308 static int cmdq_suspend(struct device *dev)
309 {
310 struct cmdq *cmdq = dev_get_drvdata(dev);
311 struct cmdq_thread *thread;
312 int i;
313 bool task_running = false;
314
315 cmdq->suspended = true;
316
317 for (i = 0; i < cmdq->thread_nr; i++) {
318 thread = &cmdq->thread[i];
319 if (!list_empty(&thread->task_busy_list)) {
320 task_running = true;
321 break;
322 }
323 }
324
325 if (task_running)
326 dev_warn(dev, "exist running task(s) in suspend\n");
327
328 clk_unprepare(cmdq->clock);
329
330 return 0;
331 }
332
cmdq_resume(struct device * dev)333 static int cmdq_resume(struct device *dev)
334 {
335 struct cmdq *cmdq = dev_get_drvdata(dev);
336
337 WARN_ON(clk_prepare(cmdq->clock) < 0);
338 cmdq->suspended = false;
339 return 0;
340 }
341
cmdq_remove(struct platform_device * pdev)342 static int cmdq_remove(struct platform_device *pdev)
343 {
344 struct cmdq *cmdq = platform_get_drvdata(pdev);
345
346 clk_unprepare(cmdq->clock);
347
348 return 0;
349 }
350
cmdq_mbox_send_data(struct mbox_chan * chan,void * data)351 static int cmdq_mbox_send_data(struct mbox_chan *chan, void *data)
352 {
353 struct cmdq_pkt *pkt = (struct cmdq_pkt *)data;
354 struct cmdq_thread *thread = (struct cmdq_thread *)chan->con_priv;
355 struct cmdq *cmdq = dev_get_drvdata(chan->mbox->dev);
356 struct cmdq_task *task;
357 unsigned long curr_pa, end_pa;
358
359 /* Client should not flush new tasks if suspended. */
360 WARN_ON(cmdq->suspended);
361
362 task = kzalloc(sizeof(*task), GFP_ATOMIC);
363 if (!task)
364 return -ENOMEM;
365
366 task->cmdq = cmdq;
367 INIT_LIST_HEAD(&task->list_entry);
368 task->pa_base = pkt->pa_base;
369 task->thread = thread;
370 task->pkt = pkt;
371
372 if (list_empty(&thread->task_busy_list)) {
373 WARN_ON(clk_enable(cmdq->clock) < 0);
374 WARN_ON(cmdq_thread_reset(cmdq, thread) < 0);
375
376 writel(task->pa_base, thread->base + CMDQ_THR_CURR_ADDR);
377 writel(task->pa_base + pkt->cmd_buf_size,
378 thread->base + CMDQ_THR_END_ADDR);
379 writel(thread->priority, thread->base + CMDQ_THR_PRIORITY);
380 writel(CMDQ_THR_IRQ_EN, thread->base + CMDQ_THR_IRQ_ENABLE);
381 writel(CMDQ_THR_ENABLED, thread->base + CMDQ_THR_ENABLE_TASK);
382 } else {
383 WARN_ON(cmdq_thread_suspend(cmdq, thread) < 0);
384 curr_pa = readl(thread->base + CMDQ_THR_CURR_ADDR);
385 end_pa = readl(thread->base + CMDQ_THR_END_ADDR);
386
387 /*
388 * Atomic execution should remove the following wfe, i.e. only
389 * wait event at first task, and prevent to pause when running.
390 */
391 if (thread->atomic_exec) {
392 /* GCE is executing if command is not WFE */
393 if (!cmdq_thread_is_in_wfe(thread)) {
394 cmdq_thread_resume(thread);
395 cmdq_thread_wait_end(thread, end_pa);
396 WARN_ON(cmdq_thread_suspend(cmdq, thread) < 0);
397 /* set to this task directly */
398 writel(task->pa_base,
399 thread->base + CMDQ_THR_CURR_ADDR);
400 } else {
401 cmdq_task_insert_into_thread(task);
402 cmdq_task_remove_wfe(task);
403 smp_mb(); /* modify jump before enable thread */
404 }
405 } else {
406 /* check boundary */
407 if (curr_pa == end_pa - CMDQ_INST_SIZE ||
408 curr_pa == end_pa) {
409 /* set to this task directly */
410 writel(task->pa_base,
411 thread->base + CMDQ_THR_CURR_ADDR);
412 } else {
413 cmdq_task_insert_into_thread(task);
414 smp_mb(); /* modify jump before enable thread */
415 }
416 }
417 writel(task->pa_base + pkt->cmd_buf_size,
418 thread->base + CMDQ_THR_END_ADDR);
419 cmdq_thread_resume(thread);
420 }
421 list_move_tail(&task->list_entry, &thread->task_busy_list);
422
423 return 0;
424 }
425
cmdq_mbox_startup(struct mbox_chan * chan)426 static int cmdq_mbox_startup(struct mbox_chan *chan)
427 {
428 return 0;
429 }
430
cmdq_mbox_shutdown(struct mbox_chan * chan)431 static void cmdq_mbox_shutdown(struct mbox_chan *chan)
432 {
433 }
434
435 static const struct mbox_chan_ops cmdq_mbox_chan_ops = {
436 .send_data = cmdq_mbox_send_data,
437 .startup = cmdq_mbox_startup,
438 .shutdown = cmdq_mbox_shutdown,
439 };
440
cmdq_xlate(struct mbox_controller * mbox,const struct of_phandle_args * sp)441 static struct mbox_chan *cmdq_xlate(struct mbox_controller *mbox,
442 const struct of_phandle_args *sp)
443 {
444 int ind = sp->args[0];
445 struct cmdq_thread *thread;
446
447 if (ind >= mbox->num_chans)
448 return ERR_PTR(-EINVAL);
449
450 thread = (struct cmdq_thread *)mbox->chans[ind].con_priv;
451 thread->priority = sp->args[1];
452 thread->atomic_exec = (sp->args[2] != 0);
453 thread->chan = &mbox->chans[ind];
454
455 return &mbox->chans[ind];
456 }
457
cmdq_probe(struct platform_device * pdev)458 static int cmdq_probe(struct platform_device *pdev)
459 {
460 struct device *dev = &pdev->dev;
461 struct resource *res;
462 struct cmdq *cmdq;
463 int err, i;
464
465 cmdq = devm_kzalloc(dev, sizeof(*cmdq), GFP_KERNEL);
466 if (!cmdq)
467 return -ENOMEM;
468
469 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
470 cmdq->base = devm_ioremap_resource(dev, res);
471 if (IS_ERR(cmdq->base)) {
472 dev_err(dev, "failed to ioremap gce\n");
473 return PTR_ERR(cmdq->base);
474 }
475
476 cmdq->irq = platform_get_irq(pdev, 0);
477 if (!cmdq->irq) {
478 dev_err(dev, "failed to get irq\n");
479 return -EINVAL;
480 }
481
482 cmdq->thread_nr = (u32)(unsigned long)of_device_get_match_data(dev);
483 cmdq->irq_mask = GENMASK(cmdq->thread_nr - 1, 0);
484 err = devm_request_irq(dev, cmdq->irq, cmdq_irq_handler, IRQF_SHARED,
485 "mtk_cmdq", cmdq);
486 if (err < 0) {
487 dev_err(dev, "failed to register ISR (%d)\n", err);
488 return err;
489 }
490
491 dev_dbg(dev, "cmdq device: addr:0x%p, va:0x%p, irq:%d\n",
492 dev, cmdq->base, cmdq->irq);
493
494 cmdq->clock = devm_clk_get(dev, "gce");
495 if (IS_ERR(cmdq->clock)) {
496 dev_err(dev, "failed to get gce clk\n");
497 return PTR_ERR(cmdq->clock);
498 }
499
500 cmdq->mbox.dev = dev;
501 cmdq->mbox.chans = devm_kcalloc(dev, cmdq->thread_nr,
502 sizeof(*cmdq->mbox.chans), GFP_KERNEL);
503 if (!cmdq->mbox.chans)
504 return -ENOMEM;
505
506 cmdq->mbox.num_chans = cmdq->thread_nr;
507 cmdq->mbox.ops = &cmdq_mbox_chan_ops;
508 cmdq->mbox.of_xlate = cmdq_xlate;
509
510 /* make use of TXDONE_BY_ACK */
511 cmdq->mbox.txdone_irq = false;
512 cmdq->mbox.txdone_poll = false;
513
514 cmdq->thread = devm_kcalloc(dev, cmdq->thread_nr,
515 sizeof(*cmdq->thread), GFP_KERNEL);
516 if (!cmdq->thread)
517 return -ENOMEM;
518
519 for (i = 0; i < cmdq->thread_nr; i++) {
520 cmdq->thread[i].base = cmdq->base + CMDQ_THR_BASE +
521 CMDQ_THR_SIZE * i;
522 INIT_LIST_HEAD(&cmdq->thread[i].task_busy_list);
523 cmdq->mbox.chans[i].con_priv = (void *)&cmdq->thread[i];
524 }
525
526 err = devm_mbox_controller_register(dev, &cmdq->mbox);
527 if (err < 0) {
528 dev_err(dev, "failed to register mailbox: %d\n", err);
529 return err;
530 }
531
532 platform_set_drvdata(pdev, cmdq);
533 WARN_ON(clk_prepare(cmdq->clock) < 0);
534
535 cmdq_init(cmdq);
536
537 return 0;
538 }
539
540 static const struct dev_pm_ops cmdq_pm_ops = {
541 .suspend = cmdq_suspend,
542 .resume = cmdq_resume,
543 };
544
545 static const struct of_device_id cmdq_of_ids[] = {
546 {.compatible = "mediatek,mt8173-gce", .data = (void *)16},
547 {.compatible = "mediatek,mt8183-gce", .data = (void *)24},
548 {}
549 };
550
551 static struct platform_driver cmdq_drv = {
552 .probe = cmdq_probe,
553 .remove = cmdq_remove,
554 .driver = {
555 .name = "mtk_cmdq",
556 .pm = &cmdq_pm_ops,
557 .of_match_table = cmdq_of_ids,
558 }
559 };
560
cmdq_drv_init(void)561 static int __init cmdq_drv_init(void)
562 {
563 return platform_driver_register(&cmdq_drv);
564 }
565
cmdq_drv_exit(void)566 static void __exit cmdq_drv_exit(void)
567 {
568 platform_driver_unregister(&cmdq_drv);
569 }
570
571 subsys_initcall(cmdq_drv_init);
572 module_exit(cmdq_drv_exit);
573
574 MODULE_LICENSE("GPL v2");
575