Merge tag 'usercopy-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees...
[sfrench/cifs-2.6.git] / drivers / dma / cppi41.c
1 #include <linux/delay.h>
2 #include <linux/dmaengine.h>
3 #include <linux/dma-mapping.h>
4 #include <linux/platform_device.h>
5 #include <linux/module.h>
6 #include <linux/of.h>
7 #include <linux/slab.h>
8 #include <linux/of_dma.h>
9 #include <linux/of_irq.h>
10 #include <linux/dmapool.h>
11 #include <linux/interrupt.h>
12 #include <linux/of_address.h>
13 #include <linux/pm_runtime.h>
14 #include "dmaengine.h"
15
16 #define DESC_TYPE       27
17 #define DESC_TYPE_HOST  0x10
18 #define DESC_TYPE_TEARD 0x13
19
20 #define TD_DESC_IS_RX   (1 << 16)
21 #define TD_DESC_DMA_NUM 10
22
23 #define DESC_LENGTH_BITS_NUM    21
24
25 #define DESC_TYPE_USB   (5 << 26)
26 #define DESC_PD_COMPLETE        (1 << 31)
27
28 /* DMA engine */
29 #define DMA_TDFDQ       4
30 #define DMA_TXGCR(x)    (0x800 + (x) * 0x20)
31 #define DMA_RXGCR(x)    (0x808 + (x) * 0x20)
32 #define RXHPCRA0                4
33
34 #define GCR_CHAN_ENABLE         (1 << 31)
35 #define GCR_TEARDOWN            (1 << 30)
36 #define GCR_STARV_RETRY         (1 << 24)
37 #define GCR_DESC_TYPE_HOST      (1 << 14)
38
39 /* DMA scheduler */
40 #define DMA_SCHED_CTRL          0
41 #define DMA_SCHED_CTRL_EN       (1 << 31)
42 #define DMA_SCHED_WORD(x)       ((x) * 4 + 0x800)
43
44 #define SCHED_ENTRY0_CHAN(x)    ((x) << 0)
45 #define SCHED_ENTRY0_IS_RX      (1 << 7)
46
47 #define SCHED_ENTRY1_CHAN(x)    ((x) << 8)
48 #define SCHED_ENTRY1_IS_RX      (1 << 15)
49
50 #define SCHED_ENTRY2_CHAN(x)    ((x) << 16)
51 #define SCHED_ENTRY2_IS_RX      (1 << 23)
52
53 #define SCHED_ENTRY3_CHAN(x)    ((x) << 24)
54 #define SCHED_ENTRY3_IS_RX      (1 << 31)
55
56 /* Queue manager */
57 /* 4 KiB of memory for descriptors, 2 for each endpoint */
58 #define ALLOC_DECS_NUM          128
59 #define DESCS_AREAS             1
60 #define TOTAL_DESCS_NUM         (ALLOC_DECS_NUM * DESCS_AREAS)
61 #define QMGR_SCRATCH_SIZE       (TOTAL_DESCS_NUM * 4)
62
63 #define QMGR_LRAM0_BASE         0x80
64 #define QMGR_LRAM_SIZE          0x84
65 #define QMGR_LRAM1_BASE         0x88
66 #define QMGR_MEMBASE(x)         (0x1000 + (x) * 0x10)
67 #define QMGR_MEMCTRL(x)         (0x1004 + (x) * 0x10)
68 #define QMGR_MEMCTRL_IDX_SH     16
69 #define QMGR_MEMCTRL_DESC_SH    8
70
71 #define QMGR_PEND(x)    (0x90 + (x) * 4)
72
73 #define QMGR_PENDING_SLOT_Q(x)  (x / 32)
74 #define QMGR_PENDING_BIT_Q(x)   (x % 32)
75
76 #define QMGR_QUEUE_A(n) (0x2000 + (n) * 0x10)
77 #define QMGR_QUEUE_B(n) (0x2004 + (n) * 0x10)
78 #define QMGR_QUEUE_C(n) (0x2008 + (n) * 0x10)
79 #define QMGR_QUEUE_D(n) (0x200c + (n) * 0x10)
80
81 /* Packet Descriptor */
82 #define PD2_ZERO_LENGTH         (1 << 19)
83
84 struct cppi41_channel {
85         struct dma_chan chan;
86         struct dma_async_tx_descriptor txd;
87         struct cppi41_dd *cdd;
88         struct cppi41_desc *desc;
89         dma_addr_t desc_phys;
90         void __iomem *gcr_reg;
91         int is_tx;
92         u32 residue;
93
94         unsigned int q_num;
95         unsigned int q_comp_num;
96         unsigned int port_num;
97
98         unsigned td_retry;
99         unsigned td_queued:1;
100         unsigned td_seen:1;
101         unsigned td_desc_seen:1;
102
103         struct list_head node;          /* Node for pending list */
104 };
105
106 struct cppi41_desc {
107         u32 pd0;
108         u32 pd1;
109         u32 pd2;
110         u32 pd3;
111         u32 pd4;
112         u32 pd5;
113         u32 pd6;
114         u32 pd7;
115 } __aligned(32);
116
117 struct chan_queues {
118         u16 submit;
119         u16 complete;
120 };
121
122 struct cppi41_dd {
123         struct dma_device ddev;
124
125         void *qmgr_scratch;
126         dma_addr_t scratch_phys;
127
128         struct cppi41_desc *cd;
129         dma_addr_t descs_phys;
130         u32 first_td_desc;
131         struct cppi41_channel *chan_busy[ALLOC_DECS_NUM];
132
133         void __iomem *ctrl_mem;
134         void __iomem *sched_mem;
135         void __iomem *qmgr_mem;
136         unsigned int irq;
137         const struct chan_queues *queues_rx;
138         const struct chan_queues *queues_tx;
139         struct chan_queues td_queue;
140         u16 first_completion_queue;
141         u16 qmgr_num_pend;
142         u32 n_chans;
143         u8 platform;
144
145         struct list_head pending;       /* Pending queued transfers */
146         spinlock_t lock;                /* Lock for pending list */
147
148         /* context for suspend/resume */
149         unsigned int dma_tdfdq;
150
151         bool is_suspended;
152 };
153
154 static struct chan_queues am335x_usb_queues_tx[] = {
155         /* USB0 ENDP 1 */
156         [ 0] = { .submit = 32, .complete =  93},
157         [ 1] = { .submit = 34, .complete =  94},
158         [ 2] = { .submit = 36, .complete =  95},
159         [ 3] = { .submit = 38, .complete =  96},
160         [ 4] = { .submit = 40, .complete =  97},
161         [ 5] = { .submit = 42, .complete =  98},
162         [ 6] = { .submit = 44, .complete =  99},
163         [ 7] = { .submit = 46, .complete = 100},
164         [ 8] = { .submit = 48, .complete = 101},
165         [ 9] = { .submit = 50, .complete = 102},
166         [10] = { .submit = 52, .complete = 103},
167         [11] = { .submit = 54, .complete = 104},
168         [12] = { .submit = 56, .complete = 105},
169         [13] = { .submit = 58, .complete = 106},
170         [14] = { .submit = 60, .complete = 107},
171
172         /* USB1 ENDP1 */
173         [15] = { .submit = 62, .complete = 125},
174         [16] = { .submit = 64, .complete = 126},
175         [17] = { .submit = 66, .complete = 127},
176         [18] = { .submit = 68, .complete = 128},
177         [19] = { .submit = 70, .complete = 129},
178         [20] = { .submit = 72, .complete = 130},
179         [21] = { .submit = 74, .complete = 131},
180         [22] = { .submit = 76, .complete = 132},
181         [23] = { .submit = 78, .complete = 133},
182         [24] = { .submit = 80, .complete = 134},
183         [25] = { .submit = 82, .complete = 135},
184         [26] = { .submit = 84, .complete = 136},
185         [27] = { .submit = 86, .complete = 137},
186         [28] = { .submit = 88, .complete = 138},
187         [29] = { .submit = 90, .complete = 139},
188 };
189
190 static const struct chan_queues am335x_usb_queues_rx[] = {
191         /* USB0 ENDP 1 */
192         [ 0] = { .submit =  1, .complete = 109},
193         [ 1] = { .submit =  2, .complete = 110},
194         [ 2] = { .submit =  3, .complete = 111},
195         [ 3] = { .submit =  4, .complete = 112},
196         [ 4] = { .submit =  5, .complete = 113},
197         [ 5] = { .submit =  6, .complete = 114},
198         [ 6] = { .submit =  7, .complete = 115},
199         [ 7] = { .submit =  8, .complete = 116},
200         [ 8] = { .submit =  9, .complete = 117},
201         [ 9] = { .submit = 10, .complete = 118},
202         [10] = { .submit = 11, .complete = 119},
203         [11] = { .submit = 12, .complete = 120},
204         [12] = { .submit = 13, .complete = 121},
205         [13] = { .submit = 14, .complete = 122},
206         [14] = { .submit = 15, .complete = 123},
207
208         /* USB1 ENDP 1 */
209         [15] = { .submit = 16, .complete = 141},
210         [16] = { .submit = 17, .complete = 142},
211         [17] = { .submit = 18, .complete = 143},
212         [18] = { .submit = 19, .complete = 144},
213         [19] = { .submit = 20, .complete = 145},
214         [20] = { .submit = 21, .complete = 146},
215         [21] = { .submit = 22, .complete = 147},
216         [22] = { .submit = 23, .complete = 148},
217         [23] = { .submit = 24, .complete = 149},
218         [24] = { .submit = 25, .complete = 150},
219         [25] = { .submit = 26, .complete = 151},
220         [26] = { .submit = 27, .complete = 152},
221         [27] = { .submit = 28, .complete = 153},
222         [28] = { .submit = 29, .complete = 154},
223         [29] = { .submit = 30, .complete = 155},
224 };
225
226 static const struct chan_queues da8xx_usb_queues_tx[] = {
227         [0] = { .submit =  16, .complete = 24},
228         [1] = { .submit =  18, .complete = 24},
229         [2] = { .submit =  20, .complete = 24},
230         [3] = { .submit =  22, .complete = 24},
231 };
232
233 static const struct chan_queues da8xx_usb_queues_rx[] = {
234         [0] = { .submit =  1, .complete = 26},
235         [1] = { .submit =  3, .complete = 26},
236         [2] = { .submit =  5, .complete = 26},
237         [3] = { .submit =  7, .complete = 26},
238 };
239
240 struct cppi_glue_infos {
241         const struct chan_queues *queues_rx;
242         const struct chan_queues *queues_tx;
243         struct chan_queues td_queue;
244         u16 first_completion_queue;
245         u16 qmgr_num_pend;
246 };
247
248 static struct cppi41_channel *to_cpp41_chan(struct dma_chan *c)
249 {
250         return container_of(c, struct cppi41_channel, chan);
251 }
252
253 static struct cppi41_channel *desc_to_chan(struct cppi41_dd *cdd, u32 desc)
254 {
255         struct cppi41_channel *c;
256         u32 descs_size;
257         u32 desc_num;
258
259         descs_size = sizeof(struct cppi41_desc) * ALLOC_DECS_NUM;
260
261         if (!((desc >= cdd->descs_phys) &&
262                         (desc < (cdd->descs_phys + descs_size)))) {
263                 return NULL;
264         }
265
266         desc_num = (desc - cdd->descs_phys) / sizeof(struct cppi41_desc);
267         BUG_ON(desc_num >= ALLOC_DECS_NUM);
268         c = cdd->chan_busy[desc_num];
269         cdd->chan_busy[desc_num] = NULL;
270
271         /* Usecount for chan_busy[], paired with push_desc_queue() */
272         pm_runtime_put(cdd->ddev.dev);
273
274         return c;
275 }
276
277 static void cppi_writel(u32 val, void *__iomem *mem)
278 {
279         __raw_writel(val, mem);
280 }
281
282 static u32 cppi_readl(void *__iomem *mem)
283 {
284         return __raw_readl(mem);
285 }
286
287 static u32 pd_trans_len(u32 val)
288 {
289         return val & ((1 << (DESC_LENGTH_BITS_NUM + 1)) - 1);
290 }
291
292 static u32 cppi41_pop_desc(struct cppi41_dd *cdd, unsigned queue_num)
293 {
294         u32 desc;
295
296         desc = cppi_readl(cdd->qmgr_mem + QMGR_QUEUE_D(queue_num));
297         desc &= ~0x1f;
298         return desc;
299 }
300
301 static irqreturn_t cppi41_irq(int irq, void *data)
302 {
303         struct cppi41_dd *cdd = data;
304         u16 first_completion_queue = cdd->first_completion_queue;
305         u16 qmgr_num_pend = cdd->qmgr_num_pend;
306         struct cppi41_channel *c;
307         int i;
308
309         for (i = QMGR_PENDING_SLOT_Q(first_completion_queue); i < qmgr_num_pend;
310                         i++) {
311                 u32 val;
312                 u32 q_num;
313
314                 val = cppi_readl(cdd->qmgr_mem + QMGR_PEND(i));
315                 if (i == QMGR_PENDING_SLOT_Q(first_completion_queue) && val) {
316                         u32 mask;
317                         /* set corresponding bit for completetion Q 93 */
318                         mask = 1 << QMGR_PENDING_BIT_Q(first_completion_queue);
319                         /* not set all bits for queues less than Q 93 */
320                         mask--;
321                         /* now invert and keep only Q 93+ set */
322                         val &= ~mask;
323                 }
324
325                 if (val)
326                         __iormb();
327
328                 while (val) {
329                         u32 desc, len;
330
331                         /*
332                          * This should never trigger, see the comments in
333                          * push_desc_queue()
334                          */
335                         WARN_ON(cdd->is_suspended);
336
337                         q_num = __fls(val);
338                         val &= ~(1 << q_num);
339                         q_num += 32 * i;
340                         desc = cppi41_pop_desc(cdd, q_num);
341                         c = desc_to_chan(cdd, desc);
342                         if (WARN_ON(!c)) {
343                                 pr_err("%s() q %d desc %08x\n", __func__,
344                                                 q_num, desc);
345                                 continue;
346                         }
347
348                         if (c->desc->pd2 & PD2_ZERO_LENGTH)
349                                 len = 0;
350                         else
351                                 len = pd_trans_len(c->desc->pd0);
352
353                         c->residue = pd_trans_len(c->desc->pd6) - len;
354                         dma_cookie_complete(&c->txd);
355                         dmaengine_desc_get_callback_invoke(&c->txd, NULL);
356                 }
357         }
358         return IRQ_HANDLED;
359 }
360
361 static dma_cookie_t cppi41_tx_submit(struct dma_async_tx_descriptor *tx)
362 {
363         dma_cookie_t cookie;
364
365         cookie = dma_cookie_assign(tx);
366
367         return cookie;
368 }
369
370 static int cppi41_dma_alloc_chan_resources(struct dma_chan *chan)
371 {
372         struct cppi41_channel *c = to_cpp41_chan(chan);
373         struct cppi41_dd *cdd = c->cdd;
374         int error;
375
376         error = pm_runtime_get_sync(cdd->ddev.dev);
377         if (error < 0) {
378                 dev_err(cdd->ddev.dev, "%s pm runtime get: %i\n",
379                         __func__, error);
380                 pm_runtime_put_noidle(cdd->ddev.dev);
381
382                 return error;
383         }
384
385         dma_cookie_init(chan);
386         dma_async_tx_descriptor_init(&c->txd, chan);
387         c->txd.tx_submit = cppi41_tx_submit;
388
389         if (!c->is_tx)
390                 cppi_writel(c->q_num, c->gcr_reg + RXHPCRA0);
391
392         pm_runtime_mark_last_busy(cdd->ddev.dev);
393         pm_runtime_put_autosuspend(cdd->ddev.dev);
394
395         return 0;
396 }
397
398 static void cppi41_dma_free_chan_resources(struct dma_chan *chan)
399 {
400         struct cppi41_channel *c = to_cpp41_chan(chan);
401         struct cppi41_dd *cdd = c->cdd;
402         int error;
403
404         error = pm_runtime_get_sync(cdd->ddev.dev);
405         if (error < 0) {
406                 pm_runtime_put_noidle(cdd->ddev.dev);
407
408                 return;
409         }
410
411         WARN_ON(!list_empty(&cdd->pending));
412
413         pm_runtime_mark_last_busy(cdd->ddev.dev);
414         pm_runtime_put_autosuspend(cdd->ddev.dev);
415 }
416
417 static enum dma_status cppi41_dma_tx_status(struct dma_chan *chan,
418         dma_cookie_t cookie, struct dma_tx_state *txstate)
419 {
420         struct cppi41_channel *c = to_cpp41_chan(chan);
421         enum dma_status ret;
422
423         ret = dma_cookie_status(chan, cookie, txstate);
424
425         dma_set_residue(txstate, c->residue);
426
427         return ret;
428 }
429
430 static void push_desc_queue(struct cppi41_channel *c)
431 {
432         struct cppi41_dd *cdd = c->cdd;
433         u32 desc_num;
434         u32 desc_phys;
435         u32 reg;
436
437         c->residue = 0;
438
439         reg = GCR_CHAN_ENABLE;
440         if (!c->is_tx) {
441                 reg |= GCR_STARV_RETRY;
442                 reg |= GCR_DESC_TYPE_HOST;
443                 reg |= c->q_comp_num;
444         }
445
446         cppi_writel(reg, c->gcr_reg);
447
448         /*
449          * We don't use writel() but __raw_writel() so we have to make sure
450          * that the DMA descriptor in coherent memory made to the main memory
451          * before starting the dma engine.
452          */
453         __iowmb();
454
455         /*
456          * DMA transfers can take at least 200ms to complete with USB mass
457          * storage connected. To prevent autosuspend timeouts, we must use
458          * pm_runtime_get/put() when chan_busy[] is modified. This will get
459          * cleared in desc_to_chan() or cppi41_stop_chan() depending on the
460          * outcome of the transfer.
461          */
462         pm_runtime_get(cdd->ddev.dev);
463
464         desc_phys = lower_32_bits(c->desc_phys);
465         desc_num = (desc_phys - cdd->descs_phys) / sizeof(struct cppi41_desc);
466         WARN_ON(cdd->chan_busy[desc_num]);
467         cdd->chan_busy[desc_num] = c;
468
469         reg = (sizeof(struct cppi41_desc) - 24) / 4;
470         reg |= desc_phys;
471         cppi_writel(reg, cdd->qmgr_mem + QMGR_QUEUE_D(c->q_num));
472 }
473
474 /*
475  * Caller must hold cdd->lock to prevent push_desc_queue()
476  * getting called out of order. We have both cppi41_dma_issue_pending()
477  * and cppi41_runtime_resume() call this function.
478  */
479 static void cppi41_run_queue(struct cppi41_dd *cdd)
480 {
481         struct cppi41_channel *c, *_c;
482
483         list_for_each_entry_safe(c, _c, &cdd->pending, node) {
484                 push_desc_queue(c);
485                 list_del(&c->node);
486         }
487 }
488
489 static void cppi41_dma_issue_pending(struct dma_chan *chan)
490 {
491         struct cppi41_channel *c = to_cpp41_chan(chan);
492         struct cppi41_dd *cdd = c->cdd;
493         unsigned long flags;
494         int error;
495
496         error = pm_runtime_get(cdd->ddev.dev);
497         if ((error != -EINPROGRESS) && error < 0) {
498                 pm_runtime_put_noidle(cdd->ddev.dev);
499                 dev_err(cdd->ddev.dev, "Failed to pm_runtime_get: %i\n",
500                         error);
501
502                 return;
503         }
504
505         spin_lock_irqsave(&cdd->lock, flags);
506         list_add_tail(&c->node, &cdd->pending);
507         if (!cdd->is_suspended)
508                 cppi41_run_queue(cdd);
509         spin_unlock_irqrestore(&cdd->lock, flags);
510
511         pm_runtime_mark_last_busy(cdd->ddev.dev);
512         pm_runtime_put_autosuspend(cdd->ddev.dev);
513 }
514
515 static u32 get_host_pd0(u32 length)
516 {
517         u32 reg;
518
519         reg = DESC_TYPE_HOST << DESC_TYPE;
520         reg |= length;
521
522         return reg;
523 }
524
525 static u32 get_host_pd1(struct cppi41_channel *c)
526 {
527         u32 reg;
528
529         reg = 0;
530
531         return reg;
532 }
533
534 static u32 get_host_pd2(struct cppi41_channel *c)
535 {
536         u32 reg;
537
538         reg = DESC_TYPE_USB;
539         reg |= c->q_comp_num;
540
541         return reg;
542 }
543
544 static u32 get_host_pd3(u32 length)
545 {
546         u32 reg;
547
548         /* PD3 = packet size */
549         reg = length;
550
551         return reg;
552 }
553
554 static u32 get_host_pd6(u32 length)
555 {
556         u32 reg;
557
558         /* PD6 buffer size */
559         reg = DESC_PD_COMPLETE;
560         reg |= length;
561
562         return reg;
563 }
564
565 static u32 get_host_pd4_or_7(u32 addr)
566 {
567         u32 reg;
568
569         reg = addr;
570
571         return reg;
572 }
573
574 static u32 get_host_pd5(void)
575 {
576         u32 reg;
577
578         reg = 0;
579
580         return reg;
581 }
582
583 static struct dma_async_tx_descriptor *cppi41_dma_prep_slave_sg(
584         struct dma_chan *chan, struct scatterlist *sgl, unsigned sg_len,
585         enum dma_transfer_direction dir, unsigned long tx_flags, void *context)
586 {
587         struct cppi41_channel *c = to_cpp41_chan(chan);
588         struct cppi41_desc *d;
589         struct scatterlist *sg;
590         unsigned int i;
591
592         d = c->desc;
593         for_each_sg(sgl, sg, sg_len, i) {
594                 u32 addr;
595                 u32 len;
596
597                 /* We need to use more than one desc once musb supports sg */
598                 addr = lower_32_bits(sg_dma_address(sg));
599                 len = sg_dma_len(sg);
600
601                 d->pd0 = get_host_pd0(len);
602                 d->pd1 = get_host_pd1(c);
603                 d->pd2 = get_host_pd2(c);
604                 d->pd3 = get_host_pd3(len);
605                 d->pd4 = get_host_pd4_or_7(addr);
606                 d->pd5 = get_host_pd5();
607                 d->pd6 = get_host_pd6(len);
608                 d->pd7 = get_host_pd4_or_7(addr);
609
610                 d++;
611         }
612
613         return &c->txd;
614 }
615
616 static void cppi41_compute_td_desc(struct cppi41_desc *d)
617 {
618         d->pd0 = DESC_TYPE_TEARD << DESC_TYPE;
619 }
620
621 static int cppi41_tear_down_chan(struct cppi41_channel *c)
622 {
623         struct dmaengine_result abort_result;
624         struct cppi41_dd *cdd = c->cdd;
625         struct cppi41_desc *td;
626         u32 reg;
627         u32 desc_phys;
628         u32 td_desc_phys;
629
630         td = cdd->cd;
631         td += cdd->first_td_desc;
632
633         td_desc_phys = cdd->descs_phys;
634         td_desc_phys += cdd->first_td_desc * sizeof(struct cppi41_desc);
635
636         if (!c->td_queued) {
637                 cppi41_compute_td_desc(td);
638                 __iowmb();
639
640                 reg = (sizeof(struct cppi41_desc) - 24) / 4;
641                 reg |= td_desc_phys;
642                 cppi_writel(reg, cdd->qmgr_mem +
643                                 QMGR_QUEUE_D(cdd->td_queue.submit));
644
645                 reg = GCR_CHAN_ENABLE;
646                 if (!c->is_tx) {
647                         reg |= GCR_STARV_RETRY;
648                         reg |= GCR_DESC_TYPE_HOST;
649                         reg |= cdd->td_queue.complete;
650                 }
651                 reg |= GCR_TEARDOWN;
652                 cppi_writel(reg, c->gcr_reg);
653                 c->td_queued = 1;
654                 c->td_retry = 500;
655         }
656
657         if (!c->td_seen || !c->td_desc_seen) {
658
659                 desc_phys = cppi41_pop_desc(cdd, cdd->td_queue.complete);
660                 if (!desc_phys && c->is_tx)
661                         desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
662
663                 if (desc_phys == c->desc_phys) {
664                         c->td_desc_seen = 1;
665
666                 } else if (desc_phys == td_desc_phys) {
667                         u32 pd0;
668
669                         __iormb();
670                         pd0 = td->pd0;
671                         WARN_ON((pd0 >> DESC_TYPE) != DESC_TYPE_TEARD);
672                         WARN_ON(!c->is_tx && !(pd0 & TD_DESC_IS_RX));
673                         WARN_ON((pd0 & 0x1f) != c->port_num);
674                         c->td_seen = 1;
675                 } else if (desc_phys) {
676                         WARN_ON_ONCE(1);
677                 }
678         }
679         c->td_retry--;
680         /*
681          * If the TX descriptor / channel is in use, the caller needs to poke
682          * his TD bit multiple times. After that he hardware releases the
683          * transfer descriptor followed by TD descriptor. Waiting seems not to
684          * cause any difference.
685          * RX seems to be thrown out right away. However once the TearDown
686          * descriptor gets through we are done. If we have seens the transfer
687          * descriptor before the TD we fetch it from enqueue, it has to be
688          * there waiting for us.
689          */
690         if (!c->td_seen && c->td_retry) {
691                 udelay(1);
692                 return -EAGAIN;
693         }
694         WARN_ON(!c->td_retry);
695
696         if (!c->td_desc_seen) {
697                 desc_phys = cppi41_pop_desc(cdd, c->q_num);
698                 if (!desc_phys)
699                         desc_phys = cppi41_pop_desc(cdd, c->q_comp_num);
700                 WARN_ON(!desc_phys);
701         }
702
703         c->td_queued = 0;
704         c->td_seen = 0;
705         c->td_desc_seen = 0;
706         cppi_writel(0, c->gcr_reg);
707
708         /* Invoke the callback to do the necessary clean-up */
709         abort_result.result = DMA_TRANS_ABORTED;
710         dma_cookie_complete(&c->txd);
711         dmaengine_desc_get_callback_invoke(&c->txd, &abort_result);
712
713         return 0;
714 }
715
716 static int cppi41_stop_chan(struct dma_chan *chan)
717 {
718         struct cppi41_channel *c = to_cpp41_chan(chan);
719         struct cppi41_dd *cdd = c->cdd;
720         u32 desc_num;
721         u32 desc_phys;
722         int ret;
723
724         desc_phys = lower_32_bits(c->desc_phys);
725         desc_num = (desc_phys - cdd->descs_phys) / sizeof(struct cppi41_desc);
726         if (!cdd->chan_busy[desc_num])
727                 return 0;
728
729         ret = cppi41_tear_down_chan(c);
730         if (ret)
731                 return ret;
732
733         WARN_ON(!cdd->chan_busy[desc_num]);
734         cdd->chan_busy[desc_num] = NULL;
735
736         /* Usecount for chan_busy[], paired with push_desc_queue() */
737         pm_runtime_put(cdd->ddev.dev);
738
739         return 0;
740 }
741
742 static int cppi41_add_chans(struct device *dev, struct cppi41_dd *cdd)
743 {
744         struct cppi41_channel *cchan, *chans;
745         int i;
746         u32 n_chans = cdd->n_chans;
747
748         /*
749          * The channels can only be used as TX or as RX. So we add twice
750          * that much dma channels because USB can only do RX or TX.
751          */
752         n_chans *= 2;
753
754         chans = devm_kcalloc(dev, n_chans, sizeof(*chans), GFP_KERNEL);
755         if (!chans)
756                 return -ENOMEM;
757
758         for (i = 0; i < n_chans; i++) {
759                 cchan = &chans[i];
760
761                 cchan->cdd = cdd;
762                 if (i & 1) {
763                         cchan->gcr_reg = cdd->ctrl_mem + DMA_TXGCR(i >> 1);
764                         cchan->is_tx = 1;
765                 } else {
766                         cchan->gcr_reg = cdd->ctrl_mem + DMA_RXGCR(i >> 1);
767                         cchan->is_tx = 0;
768                 }
769                 cchan->port_num = i >> 1;
770                 cchan->desc = &cdd->cd[i];
771                 cchan->desc_phys = cdd->descs_phys;
772                 cchan->desc_phys += i * sizeof(struct cppi41_desc);
773                 cchan->chan.device = &cdd->ddev;
774                 list_add_tail(&cchan->chan.device_node, &cdd->ddev.channels);
775         }
776         cdd->first_td_desc = n_chans;
777
778         return 0;
779 }
780
781 static void purge_descs(struct device *dev, struct cppi41_dd *cdd)
782 {
783         unsigned int mem_decs;
784         int i;
785
786         mem_decs = ALLOC_DECS_NUM * sizeof(struct cppi41_desc);
787
788         for (i = 0; i < DESCS_AREAS; i++) {
789
790                 cppi_writel(0, cdd->qmgr_mem + QMGR_MEMBASE(i));
791                 cppi_writel(0, cdd->qmgr_mem + QMGR_MEMCTRL(i));
792
793                 dma_free_coherent(dev, mem_decs, cdd->cd,
794                                 cdd->descs_phys);
795         }
796 }
797
798 static void disable_sched(struct cppi41_dd *cdd)
799 {
800         cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
801 }
802
803 static void deinit_cppi41(struct device *dev, struct cppi41_dd *cdd)
804 {
805         disable_sched(cdd);
806
807         purge_descs(dev, cdd);
808
809         cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM0_BASE);
810         cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM0_BASE);
811         dma_free_coherent(dev, QMGR_SCRATCH_SIZE, cdd->qmgr_scratch,
812                         cdd->scratch_phys);
813 }
814
815 static int init_descs(struct device *dev, struct cppi41_dd *cdd)
816 {
817         unsigned int desc_size;
818         unsigned int mem_decs;
819         int i;
820         u32 reg;
821         u32 idx;
822
823         BUILD_BUG_ON(sizeof(struct cppi41_desc) &
824                         (sizeof(struct cppi41_desc) - 1));
825         BUILD_BUG_ON(sizeof(struct cppi41_desc) < 32);
826         BUILD_BUG_ON(ALLOC_DECS_NUM < 32);
827
828         desc_size = sizeof(struct cppi41_desc);
829         mem_decs = ALLOC_DECS_NUM * desc_size;
830
831         idx = 0;
832         for (i = 0; i < DESCS_AREAS; i++) {
833
834                 reg = idx << QMGR_MEMCTRL_IDX_SH;
835                 reg |= (ilog2(desc_size) - 5) << QMGR_MEMCTRL_DESC_SH;
836                 reg |= ilog2(ALLOC_DECS_NUM) - 5;
837
838                 BUILD_BUG_ON(DESCS_AREAS != 1);
839                 cdd->cd = dma_alloc_coherent(dev, mem_decs,
840                                 &cdd->descs_phys, GFP_KERNEL);
841                 if (!cdd->cd)
842                         return -ENOMEM;
843
844                 cppi_writel(cdd->descs_phys, cdd->qmgr_mem + QMGR_MEMBASE(i));
845                 cppi_writel(reg, cdd->qmgr_mem + QMGR_MEMCTRL(i));
846
847                 idx += ALLOC_DECS_NUM;
848         }
849         return 0;
850 }
851
852 static void init_sched(struct cppi41_dd *cdd)
853 {
854         unsigned ch;
855         unsigned word;
856         u32 reg;
857
858         word = 0;
859         cppi_writel(0, cdd->sched_mem + DMA_SCHED_CTRL);
860         for (ch = 0; ch < cdd->n_chans; ch += 2) {
861
862                 reg = SCHED_ENTRY0_CHAN(ch);
863                 reg |= SCHED_ENTRY1_CHAN(ch) | SCHED_ENTRY1_IS_RX;
864
865                 reg |= SCHED_ENTRY2_CHAN(ch + 1);
866                 reg |= SCHED_ENTRY3_CHAN(ch + 1) | SCHED_ENTRY3_IS_RX;
867                 cppi_writel(reg, cdd->sched_mem + DMA_SCHED_WORD(word));
868                 word++;
869         }
870         reg = cdd->n_chans * 2 - 1;
871         reg |= DMA_SCHED_CTRL_EN;
872         cppi_writel(reg, cdd->sched_mem + DMA_SCHED_CTRL);
873 }
874
875 static int init_cppi41(struct device *dev, struct cppi41_dd *cdd)
876 {
877         int ret;
878
879         BUILD_BUG_ON(QMGR_SCRATCH_SIZE > ((1 << 14) - 1));
880         cdd->qmgr_scratch = dma_alloc_coherent(dev, QMGR_SCRATCH_SIZE,
881                         &cdd->scratch_phys, GFP_KERNEL);
882         if (!cdd->qmgr_scratch)
883                 return -ENOMEM;
884
885         cppi_writel(cdd->scratch_phys, cdd->qmgr_mem + QMGR_LRAM0_BASE);
886         cppi_writel(TOTAL_DESCS_NUM, cdd->qmgr_mem + QMGR_LRAM_SIZE);
887         cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM1_BASE);
888
889         ret = init_descs(dev, cdd);
890         if (ret)
891                 goto err_td;
892
893         cppi_writel(cdd->td_queue.submit, cdd->ctrl_mem + DMA_TDFDQ);
894         init_sched(cdd);
895
896         return 0;
897 err_td:
898         deinit_cppi41(dev, cdd);
899         return ret;
900 }
901
902 static struct platform_driver cpp41_dma_driver;
903 /*
904  * The param format is:
905  * X Y
906  * X: Port
907  * Y: 0 = RX else TX
908  */
909 #define INFO_PORT       0
910 #define INFO_IS_TX      1
911
912 static bool cpp41_dma_filter_fn(struct dma_chan *chan, void *param)
913 {
914         struct cppi41_channel *cchan;
915         struct cppi41_dd *cdd;
916         const struct chan_queues *queues;
917         u32 *num = param;
918
919         if (chan->device->dev->driver != &cpp41_dma_driver.driver)
920                 return false;
921
922         cchan = to_cpp41_chan(chan);
923
924         if (cchan->port_num != num[INFO_PORT])
925                 return false;
926
927         if (cchan->is_tx && !num[INFO_IS_TX])
928                 return false;
929         cdd = cchan->cdd;
930         if (cchan->is_tx)
931                 queues = cdd->queues_tx;
932         else
933                 queues = cdd->queues_rx;
934
935         BUILD_BUG_ON(ARRAY_SIZE(am335x_usb_queues_rx) !=
936                      ARRAY_SIZE(am335x_usb_queues_tx));
937         if (WARN_ON(cchan->port_num >= ARRAY_SIZE(am335x_usb_queues_rx)))
938                 return false;
939
940         cchan->q_num = queues[cchan->port_num].submit;
941         cchan->q_comp_num = queues[cchan->port_num].complete;
942         return true;
943 }
944
945 static struct of_dma_filter_info cpp41_dma_info = {
946         .filter_fn = cpp41_dma_filter_fn,
947 };
948
949 static struct dma_chan *cppi41_dma_xlate(struct of_phandle_args *dma_spec,
950                 struct of_dma *ofdma)
951 {
952         int count = dma_spec->args_count;
953         struct of_dma_filter_info *info = ofdma->of_dma_data;
954
955         if (!info || !info->filter_fn)
956                 return NULL;
957
958         if (count != 2)
959                 return NULL;
960
961         return dma_request_channel(info->dma_cap, info->filter_fn,
962                         &dma_spec->args[0]);
963 }
964
965 static const struct cppi_glue_infos am335x_usb_infos = {
966         .queues_rx = am335x_usb_queues_rx,
967         .queues_tx = am335x_usb_queues_tx,
968         .td_queue = { .submit = 31, .complete = 0 },
969         .first_completion_queue = 93,
970         .qmgr_num_pend = 5,
971 };
972
973 static const struct cppi_glue_infos da8xx_usb_infos = {
974         .queues_rx = da8xx_usb_queues_rx,
975         .queues_tx = da8xx_usb_queues_tx,
976         .td_queue = { .submit = 31, .complete = 0 },
977         .first_completion_queue = 24,
978         .qmgr_num_pend = 2,
979 };
980
981 static const struct of_device_id cppi41_dma_ids[] = {
982         { .compatible = "ti,am3359-cppi41", .data = &am335x_usb_infos},
983         { .compatible = "ti,da830-cppi41", .data = &da8xx_usb_infos},
984         {},
985 };
986 MODULE_DEVICE_TABLE(of, cppi41_dma_ids);
987
988 static const struct cppi_glue_infos *get_glue_info(struct device *dev)
989 {
990         const struct of_device_id *of_id;
991
992         of_id = of_match_node(cppi41_dma_ids, dev->of_node);
993         if (!of_id)
994                 return NULL;
995         return of_id->data;
996 }
997
998 #define CPPI41_DMA_BUSWIDTHS    (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
999                                 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
1000                                 BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
1001                                 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
1002
1003 static int cppi41_dma_probe(struct platform_device *pdev)
1004 {
1005         struct cppi41_dd *cdd;
1006         struct device *dev = &pdev->dev;
1007         const struct cppi_glue_infos *glue_info;
1008         struct resource *mem;
1009         int index;
1010         int irq;
1011         int ret;
1012
1013         glue_info = get_glue_info(dev);
1014         if (!glue_info)
1015                 return -EINVAL;
1016
1017         cdd = devm_kzalloc(&pdev->dev, sizeof(*cdd), GFP_KERNEL);
1018         if (!cdd)
1019                 return -ENOMEM;
1020
1021         dma_cap_set(DMA_SLAVE, cdd->ddev.cap_mask);
1022         cdd->ddev.device_alloc_chan_resources = cppi41_dma_alloc_chan_resources;
1023         cdd->ddev.device_free_chan_resources = cppi41_dma_free_chan_resources;
1024         cdd->ddev.device_tx_status = cppi41_dma_tx_status;
1025         cdd->ddev.device_issue_pending = cppi41_dma_issue_pending;
1026         cdd->ddev.device_prep_slave_sg = cppi41_dma_prep_slave_sg;
1027         cdd->ddev.device_terminate_all = cppi41_stop_chan;
1028         cdd->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1029         cdd->ddev.src_addr_widths = CPPI41_DMA_BUSWIDTHS;
1030         cdd->ddev.dst_addr_widths = CPPI41_DMA_BUSWIDTHS;
1031         cdd->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1032         cdd->ddev.dev = dev;
1033         INIT_LIST_HEAD(&cdd->ddev.channels);
1034         cpp41_dma_info.dma_cap = cdd->ddev.cap_mask;
1035
1036         index = of_property_match_string(dev->of_node,
1037                                          "reg-names", "controller");
1038         if (index < 0)
1039                 return index;
1040
1041         mem = platform_get_resource(pdev, IORESOURCE_MEM, index);
1042         cdd->ctrl_mem = devm_ioremap_resource(dev, mem);
1043         if (IS_ERR(cdd->ctrl_mem))
1044                 return PTR_ERR(cdd->ctrl_mem);
1045
1046         mem = platform_get_resource(pdev, IORESOURCE_MEM, index + 1);
1047         cdd->sched_mem = devm_ioremap_resource(dev, mem);
1048         if (IS_ERR(cdd->sched_mem))
1049                 return PTR_ERR(cdd->sched_mem);
1050
1051         mem = platform_get_resource(pdev, IORESOURCE_MEM, index + 2);
1052         cdd->qmgr_mem = devm_ioremap_resource(dev, mem);
1053         if (IS_ERR(cdd->qmgr_mem))
1054                 return PTR_ERR(cdd->qmgr_mem);
1055
1056         spin_lock_init(&cdd->lock);
1057         INIT_LIST_HEAD(&cdd->pending);
1058
1059         platform_set_drvdata(pdev, cdd);
1060
1061         pm_runtime_enable(dev);
1062         pm_runtime_set_autosuspend_delay(dev, 100);
1063         pm_runtime_use_autosuspend(dev);
1064         ret = pm_runtime_get_sync(dev);
1065         if (ret < 0)
1066                 goto err_get_sync;
1067
1068         cdd->queues_rx = glue_info->queues_rx;
1069         cdd->queues_tx = glue_info->queues_tx;
1070         cdd->td_queue = glue_info->td_queue;
1071         cdd->qmgr_num_pend = glue_info->qmgr_num_pend;
1072         cdd->first_completion_queue = glue_info->first_completion_queue;
1073
1074         ret = of_property_read_u32(dev->of_node,
1075                                    "#dma-channels", &cdd->n_chans);
1076         if (ret)
1077                 goto err_get_n_chans;
1078
1079         ret = init_cppi41(dev, cdd);
1080         if (ret)
1081                 goto err_init_cppi;
1082
1083         ret = cppi41_add_chans(dev, cdd);
1084         if (ret)
1085                 goto err_chans;
1086
1087         irq = irq_of_parse_and_map(dev->of_node, 0);
1088         if (!irq) {
1089                 ret = -EINVAL;
1090                 goto err_chans;
1091         }
1092
1093         ret = devm_request_irq(&pdev->dev, irq, cppi41_irq, IRQF_SHARED,
1094                         dev_name(dev), cdd);
1095         if (ret)
1096                 goto err_chans;
1097         cdd->irq = irq;
1098
1099         ret = dma_async_device_register(&cdd->ddev);
1100         if (ret)
1101                 goto err_chans;
1102
1103         ret = of_dma_controller_register(dev->of_node,
1104                         cppi41_dma_xlate, &cpp41_dma_info);
1105         if (ret)
1106                 goto err_of;
1107
1108         pm_runtime_mark_last_busy(dev);
1109         pm_runtime_put_autosuspend(dev);
1110
1111         return 0;
1112 err_of:
1113         dma_async_device_unregister(&cdd->ddev);
1114 err_chans:
1115         deinit_cppi41(dev, cdd);
1116 err_init_cppi:
1117         pm_runtime_dont_use_autosuspend(dev);
1118 err_get_n_chans:
1119 err_get_sync:
1120         pm_runtime_put_sync(dev);
1121         pm_runtime_disable(dev);
1122         return ret;
1123 }
1124
1125 static int cppi41_dma_remove(struct platform_device *pdev)
1126 {
1127         struct cppi41_dd *cdd = platform_get_drvdata(pdev);
1128         int error;
1129
1130         error = pm_runtime_get_sync(&pdev->dev);
1131         if (error < 0)
1132                 dev_err(&pdev->dev, "%s could not pm_runtime_get: %i\n",
1133                         __func__, error);
1134         of_dma_controller_free(pdev->dev.of_node);
1135         dma_async_device_unregister(&cdd->ddev);
1136
1137         devm_free_irq(&pdev->dev, cdd->irq, cdd);
1138         deinit_cppi41(&pdev->dev, cdd);
1139         pm_runtime_dont_use_autosuspend(&pdev->dev);
1140         pm_runtime_put_sync(&pdev->dev);
1141         pm_runtime_disable(&pdev->dev);
1142         return 0;
1143 }
1144
1145 static int __maybe_unused cppi41_suspend(struct device *dev)
1146 {
1147         struct cppi41_dd *cdd = dev_get_drvdata(dev);
1148
1149         cdd->dma_tdfdq = cppi_readl(cdd->ctrl_mem + DMA_TDFDQ);
1150         disable_sched(cdd);
1151
1152         return 0;
1153 }
1154
1155 static int __maybe_unused cppi41_resume(struct device *dev)
1156 {
1157         struct cppi41_dd *cdd = dev_get_drvdata(dev);
1158         struct cppi41_channel *c;
1159         int i;
1160
1161         for (i = 0; i < DESCS_AREAS; i++)
1162                 cppi_writel(cdd->descs_phys, cdd->qmgr_mem + QMGR_MEMBASE(i));
1163
1164         list_for_each_entry(c, &cdd->ddev.channels, chan.device_node)
1165                 if (!c->is_tx)
1166                         cppi_writel(c->q_num, c->gcr_reg + RXHPCRA0);
1167
1168         init_sched(cdd);
1169
1170         cppi_writel(cdd->dma_tdfdq, cdd->ctrl_mem + DMA_TDFDQ);
1171         cppi_writel(cdd->scratch_phys, cdd->qmgr_mem + QMGR_LRAM0_BASE);
1172         cppi_writel(QMGR_SCRATCH_SIZE, cdd->qmgr_mem + QMGR_LRAM_SIZE);
1173         cppi_writel(0, cdd->qmgr_mem + QMGR_LRAM1_BASE);
1174
1175         return 0;
1176 }
1177
1178 static int __maybe_unused cppi41_runtime_suspend(struct device *dev)
1179 {
1180         struct cppi41_dd *cdd = dev_get_drvdata(dev);
1181         unsigned long flags;
1182
1183         spin_lock_irqsave(&cdd->lock, flags);
1184         cdd->is_suspended = true;
1185         WARN_ON(!list_empty(&cdd->pending));
1186         spin_unlock_irqrestore(&cdd->lock, flags);
1187
1188         return 0;
1189 }
1190
1191 static int __maybe_unused cppi41_runtime_resume(struct device *dev)
1192 {
1193         struct cppi41_dd *cdd = dev_get_drvdata(dev);
1194         unsigned long flags;
1195
1196         spin_lock_irqsave(&cdd->lock, flags);
1197         cdd->is_suspended = false;
1198         cppi41_run_queue(cdd);
1199         spin_unlock_irqrestore(&cdd->lock, flags);
1200
1201         return 0;
1202 }
1203
1204 static const struct dev_pm_ops cppi41_pm_ops = {
1205         SET_LATE_SYSTEM_SLEEP_PM_OPS(cppi41_suspend, cppi41_resume)
1206         SET_RUNTIME_PM_OPS(cppi41_runtime_suspend,
1207                            cppi41_runtime_resume,
1208                            NULL)
1209 };
1210
1211 static struct platform_driver cpp41_dma_driver = {
1212         .probe  = cppi41_dma_probe,
1213         .remove = cppi41_dma_remove,
1214         .driver = {
1215                 .name = "cppi41-dma-engine",
1216                 .pm = &cppi41_pm_ops,
1217                 .of_match_table = of_match_ptr(cppi41_dma_ids),
1218         },
1219 };
1220
1221 module_platform_driver(cpp41_dma_driver);
1222 MODULE_LICENSE("GPL");
1223 MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");