objtool: Re-arrange validate_functions()
[linux-block.git] / drivers / staging / mt7621-dma / mtk-hsdma.c
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  Copyright (C) 2015, Michael Lee <igvtee@gmail.com>
4  *  MTK HSDMA support
5  */
6
7 #include <linux/dmaengine.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/err.h>
10 #include <linux/init.h>
11 #include <linux/list.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16 #include <linux/irq.h>
17 #include <linux/of_dma.h>
18 #include <linux/reset.h>
19 #include <linux/of_device.h>
20
21 #include "virt-dma.h"
22
23 #define HSDMA_BASE_OFFSET               0x800
24
25 #define HSDMA_REG_TX_BASE               0x00
26 #define HSDMA_REG_TX_CNT                0x04
27 #define HSDMA_REG_TX_CTX                0x08
28 #define HSDMA_REG_TX_DTX                0x0c
29 #define HSDMA_REG_RX_BASE               0x100
30 #define HSDMA_REG_RX_CNT                0x104
31 #define HSDMA_REG_RX_CRX                0x108
32 #define HSDMA_REG_RX_DRX                0x10c
33 #define HSDMA_REG_INFO                  0x200
34 #define HSDMA_REG_GLO_CFG               0x204
35 #define HSDMA_REG_RST_CFG               0x208
36 #define HSDMA_REG_DELAY_INT             0x20c
37 #define HSDMA_REG_FREEQ_THRES           0x210
38 #define HSDMA_REG_INT_STATUS            0x220
39 #define HSDMA_REG_INT_MASK              0x228
40 #define HSDMA_REG_SCH_Q01               0x280
41 #define HSDMA_REG_SCH_Q23               0x284
42
43 #define HSDMA_DESCS_MAX                 0xfff
44 #define HSDMA_DESCS_NUM                 8
45 #define HSDMA_DESCS_MASK                (HSDMA_DESCS_NUM - 1)
46 #define HSDMA_NEXT_DESC(x)              (((x) + 1) & HSDMA_DESCS_MASK)
47
48 /* HSDMA_REG_INFO */
49 #define HSDMA_INFO_INDEX_MASK           0xf
50 #define HSDMA_INFO_INDEX_SHIFT          24
51 #define HSDMA_INFO_BASE_MASK            0xff
52 #define HSDMA_INFO_BASE_SHIFT           16
53 #define HSDMA_INFO_RX_MASK              0xff
54 #define HSDMA_INFO_RX_SHIFT             8
55 #define HSDMA_INFO_TX_MASK              0xff
56 #define HSDMA_INFO_TX_SHIFT             0
57
58 /* HSDMA_REG_GLO_CFG */
59 #define HSDMA_GLO_TX_2B_OFFSET          BIT(31)
60 #define HSDMA_GLO_CLK_GATE              BIT(30)
61 #define HSDMA_GLO_BYTE_SWAP             BIT(29)
62 #define HSDMA_GLO_MULTI_DMA             BIT(10)
63 #define HSDMA_GLO_TWO_BUF               BIT(9)
64 #define HSDMA_GLO_32B_DESC              BIT(8)
65 #define HSDMA_GLO_BIG_ENDIAN            BIT(7)
66 #define HSDMA_GLO_TX_DONE               BIT(6)
67 #define HSDMA_GLO_BT_MASK               0x3
68 #define HSDMA_GLO_BT_SHIFT              4
69 #define HSDMA_GLO_RX_BUSY               BIT(3)
70 #define HSDMA_GLO_RX_DMA                BIT(2)
71 #define HSDMA_GLO_TX_BUSY               BIT(1)
72 #define HSDMA_GLO_TX_DMA                BIT(0)
73
74 #define HSDMA_BT_SIZE_16BYTES           (0 << HSDMA_GLO_BT_SHIFT)
75 #define HSDMA_BT_SIZE_32BYTES           (1 << HSDMA_GLO_BT_SHIFT)
76 #define HSDMA_BT_SIZE_64BYTES           (2 << HSDMA_GLO_BT_SHIFT)
77 #define HSDMA_BT_SIZE_128BYTES          (3 << HSDMA_GLO_BT_SHIFT)
78
79 #define HSDMA_GLO_DEFAULT               (HSDMA_GLO_MULTI_DMA | \
80                 HSDMA_GLO_RX_DMA | HSDMA_GLO_TX_DMA | HSDMA_BT_SIZE_32BYTES)
81
82 /* HSDMA_REG_RST_CFG */
83 #define HSDMA_RST_RX_SHIFT              16
84 #define HSDMA_RST_TX_SHIFT              0
85
86 /* HSDMA_REG_DELAY_INT */
87 #define HSDMA_DELAY_INT_EN              BIT(15)
88 #define HSDMA_DELAY_PEND_OFFSET         8
89 #define HSDMA_DELAY_TIME_OFFSET         0
90 #define HSDMA_DELAY_TX_OFFSET           16
91 #define HSDMA_DELAY_RX_OFFSET           0
92
93 #define HSDMA_DELAY_INIT(x)             (HSDMA_DELAY_INT_EN | \
94                 ((x) << HSDMA_DELAY_PEND_OFFSET))
95 #define HSDMA_DELAY(x)                  ((HSDMA_DELAY_INIT(x) << \
96                 HSDMA_DELAY_TX_OFFSET) | HSDMA_DELAY_INIT(x))
97
98 /* HSDMA_REG_INT_STATUS */
99 #define HSDMA_INT_DELAY_RX_COH          BIT(31)
100 #define HSDMA_INT_DELAY_RX_INT          BIT(30)
101 #define HSDMA_INT_DELAY_TX_COH          BIT(29)
102 #define HSDMA_INT_DELAY_TX_INT          BIT(28)
103 #define HSDMA_INT_RX_MASK               0x3
104 #define HSDMA_INT_RX_SHIFT              16
105 #define HSDMA_INT_RX_Q0                 BIT(16)
106 #define HSDMA_INT_TX_MASK               0xf
107 #define HSDMA_INT_TX_SHIFT              0
108 #define HSDMA_INT_TX_Q0                 BIT(0)
109
110 /* tx/rx dma desc flags */
111 #define HSDMA_PLEN_MASK                 0x3fff
112 #define HSDMA_DESC_DONE                 BIT(31)
113 #define HSDMA_DESC_LS0                  BIT(30)
114 #define HSDMA_DESC_PLEN0(_x)            (((_x) & HSDMA_PLEN_MASK) << 16)
115 #define HSDMA_DESC_TAG                  BIT(15)
116 #define HSDMA_DESC_LS1                  BIT(14)
117 #define HSDMA_DESC_PLEN1(_x)            ((_x) & HSDMA_PLEN_MASK)
118
119 /* align 4 bytes */
120 #define HSDMA_ALIGN_SIZE                3
121 /* align size 128bytes */
122 #define HSDMA_MAX_PLEN                  0x3f80
123
124 struct hsdma_desc {
125         u32 addr0;
126         u32 flags;
127         u32 addr1;
128         u32 unused;
129 };
130
131 struct mtk_hsdma_sg {
132         dma_addr_t src_addr;
133         dma_addr_t dst_addr;
134         u32 len;
135 };
136
137 struct mtk_hsdma_desc {
138         struct virt_dma_desc vdesc;
139         unsigned int num_sgs;
140         struct mtk_hsdma_sg sg[1];
141 };
142
143 struct mtk_hsdma_chan {
144         struct virt_dma_chan vchan;
145         unsigned int id;
146         dma_addr_t desc_addr;
147         int tx_idx;
148         int rx_idx;
149         struct hsdma_desc *tx_ring;
150         struct hsdma_desc *rx_ring;
151         struct mtk_hsdma_desc *desc;
152         unsigned int next_sg;
153 };
154
155 struct mtk_hsdam_engine {
156         struct dma_device ddev;
157         struct device_dma_parameters dma_parms;
158         void __iomem *base;
159         struct tasklet_struct task;
160         volatile unsigned long chan_issued;
161
162         struct mtk_hsdma_chan chan[1];
163 };
164
165 static inline struct mtk_hsdam_engine *mtk_hsdma_chan_get_dev(
166                 struct mtk_hsdma_chan *chan)
167 {
168         return container_of(chan->vchan.chan.device, struct mtk_hsdam_engine,
169                         ddev);
170 }
171
172 static inline struct mtk_hsdma_chan *to_mtk_hsdma_chan(struct dma_chan *c)
173 {
174         return container_of(c, struct mtk_hsdma_chan, vchan.chan);
175 }
176
177 static inline struct mtk_hsdma_desc *to_mtk_hsdma_desc(
178                 struct virt_dma_desc *vdesc)
179 {
180         return container_of(vdesc, struct mtk_hsdma_desc, vdesc);
181 }
182
183 static inline u32 mtk_hsdma_read(struct mtk_hsdam_engine *hsdma, u32 reg)
184 {
185         return readl(hsdma->base + reg);
186 }
187
188 static inline void mtk_hsdma_write(struct mtk_hsdam_engine *hsdma,
189                                    unsigned int reg, u32 val)
190 {
191         writel(val, hsdma->base + reg);
192 }
193
194 static void mtk_hsdma_reset_chan(struct mtk_hsdam_engine *hsdma,
195                                  struct mtk_hsdma_chan *chan)
196 {
197         chan->tx_idx = 0;
198         chan->rx_idx = HSDMA_DESCS_NUM - 1;
199
200         mtk_hsdma_write(hsdma, HSDMA_REG_TX_CTX, chan->tx_idx);
201         mtk_hsdma_write(hsdma, HSDMA_REG_RX_CRX, chan->rx_idx);
202
203         mtk_hsdma_write(hsdma, HSDMA_REG_RST_CFG,
204                         0x1 << (chan->id + HSDMA_RST_TX_SHIFT));
205         mtk_hsdma_write(hsdma, HSDMA_REG_RST_CFG,
206                         0x1 << (chan->id + HSDMA_RST_RX_SHIFT));
207 }
208
209 static void hsdma_dump_reg(struct mtk_hsdam_engine *hsdma)
210 {
211         dev_dbg(hsdma->ddev.dev, "tbase %08x, tcnt %08x, "
212                         "tctx %08x, tdtx: %08x, rbase %08x, "
213                         "rcnt %08x, rctx %08x, rdtx %08x\n",
214                         mtk_hsdma_read(hsdma, HSDMA_REG_TX_BASE),
215                         mtk_hsdma_read(hsdma, HSDMA_REG_TX_CNT),
216                         mtk_hsdma_read(hsdma, HSDMA_REG_TX_CTX),
217                         mtk_hsdma_read(hsdma, HSDMA_REG_TX_DTX),
218                         mtk_hsdma_read(hsdma, HSDMA_REG_RX_BASE),
219                         mtk_hsdma_read(hsdma, HSDMA_REG_RX_CNT),
220                         mtk_hsdma_read(hsdma, HSDMA_REG_RX_CRX),
221                         mtk_hsdma_read(hsdma, HSDMA_REG_RX_DRX));
222
223         dev_dbg(hsdma->ddev.dev, "info %08x, glo %08x, delay %08x, "
224                         "intr_stat %08x, intr_mask %08x\n",
225                         mtk_hsdma_read(hsdma, HSDMA_REG_INFO),
226                         mtk_hsdma_read(hsdma, HSDMA_REG_GLO_CFG),
227                         mtk_hsdma_read(hsdma, HSDMA_REG_DELAY_INT),
228                         mtk_hsdma_read(hsdma, HSDMA_REG_INT_STATUS),
229                         mtk_hsdma_read(hsdma, HSDMA_REG_INT_MASK));
230 }
231
232 static void hsdma_dump_desc(struct mtk_hsdam_engine *hsdma,
233                             struct mtk_hsdma_chan *chan)
234 {
235         struct hsdma_desc *tx_desc;
236         struct hsdma_desc *rx_desc;
237         int i;
238
239         dev_dbg(hsdma->ddev.dev, "tx idx: %d, rx idx: %d\n",
240                 chan->tx_idx, chan->rx_idx);
241
242         for (i = 0; i < HSDMA_DESCS_NUM; i++) {
243                 tx_desc = &chan->tx_ring[i];
244                 rx_desc = &chan->rx_ring[i];
245
246                 dev_dbg(hsdma->ddev.dev, "%d tx addr0: %08x, flags %08x, "
247                                 "tx addr1: %08x, rx addr0 %08x, flags %08x\n",
248                                 i, tx_desc->addr0, tx_desc->flags,
249                                 tx_desc->addr1, rx_desc->addr0, rx_desc->flags);
250         }
251 }
252
253 static void mtk_hsdma_reset(struct mtk_hsdam_engine *hsdma,
254                             struct mtk_hsdma_chan *chan)
255 {
256         int i;
257
258         /* disable dma */
259         mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, 0);
260
261         /* disable intr */
262         mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, 0);
263
264         /* init desc value */
265         for (i = 0; i < HSDMA_DESCS_NUM; i++) {
266                 chan->tx_ring[i].addr0 = 0;
267                 chan->tx_ring[i].flags = HSDMA_DESC_LS0 | HSDMA_DESC_DONE;
268         }
269         for (i = 0; i < HSDMA_DESCS_NUM; i++) {
270                 chan->rx_ring[i].addr0 = 0;
271                 chan->rx_ring[i].flags = 0;
272         }
273
274         /* reset */
275         mtk_hsdma_reset_chan(hsdma, chan);
276
277         /* enable intr */
278         mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, HSDMA_INT_RX_Q0);
279
280         /* enable dma */
281         mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, HSDMA_GLO_DEFAULT);
282 }
283
284 static int mtk_hsdma_terminate_all(struct dma_chan *c)
285 {
286         struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
287         struct mtk_hsdam_engine *hsdma = mtk_hsdma_chan_get_dev(chan);
288         unsigned long timeout;
289         LIST_HEAD(head);
290
291         spin_lock_bh(&chan->vchan.lock);
292         chan->desc = NULL;
293         clear_bit(chan->id, &hsdma->chan_issued);
294         vchan_get_all_descriptors(&chan->vchan, &head);
295         spin_unlock_bh(&chan->vchan.lock);
296
297         vchan_dma_desc_free_list(&chan->vchan, &head);
298
299         /* wait dma transfer complete */
300         timeout = jiffies + msecs_to_jiffies(2000);
301         while (mtk_hsdma_read(hsdma, HSDMA_REG_GLO_CFG) &
302                         (HSDMA_GLO_RX_BUSY | HSDMA_GLO_TX_BUSY)) {
303                 if (time_after_eq(jiffies, timeout)) {
304                         hsdma_dump_desc(hsdma, chan);
305                         mtk_hsdma_reset(hsdma, chan);
306                         dev_err(hsdma->ddev.dev, "timeout, reset it\n");
307                         break;
308                 }
309                 cpu_relax();
310         }
311
312         return 0;
313 }
314
315 static int mtk_hsdma_start_transfer(struct mtk_hsdam_engine *hsdma,
316                                     struct mtk_hsdma_chan *chan)
317 {
318         dma_addr_t src, dst;
319         size_t len, tlen;
320         struct hsdma_desc *tx_desc, *rx_desc;
321         struct mtk_hsdma_sg *sg;
322         unsigned int i;
323         int rx_idx;
324
325         sg = &chan->desc->sg[0];
326         len = sg->len;
327         chan->desc->num_sgs = DIV_ROUND_UP(len, HSDMA_MAX_PLEN);
328
329         /* tx desc */
330         src = sg->src_addr;
331         for (i = 0; i < chan->desc->num_sgs; i++) {
332                 tx_desc = &chan->tx_ring[chan->tx_idx];
333
334                 if (len > HSDMA_MAX_PLEN)
335                         tlen = HSDMA_MAX_PLEN;
336                 else
337                         tlen = len;
338
339                 if (i & 0x1) {
340                         tx_desc->addr1 = src;
341                         tx_desc->flags |= HSDMA_DESC_PLEN1(tlen);
342                 } else {
343                         tx_desc->addr0 = src;
344                         tx_desc->flags = HSDMA_DESC_PLEN0(tlen);
345
346                         /* update index */
347                         chan->tx_idx = HSDMA_NEXT_DESC(chan->tx_idx);
348                 }
349
350                 src += tlen;
351                 len -= tlen;
352         }
353         if (i & 0x1)
354                 tx_desc->flags |= HSDMA_DESC_LS0;
355         else
356                 tx_desc->flags |= HSDMA_DESC_LS1;
357
358         /* rx desc */
359         rx_idx = HSDMA_NEXT_DESC(chan->rx_idx);
360         len = sg->len;
361         dst = sg->dst_addr;
362         for (i = 0; i < chan->desc->num_sgs; i++) {
363                 rx_desc = &chan->rx_ring[rx_idx];
364                 if (len > HSDMA_MAX_PLEN)
365                         tlen = HSDMA_MAX_PLEN;
366                 else
367                         tlen = len;
368
369                 rx_desc->addr0 = dst;
370                 rx_desc->flags = HSDMA_DESC_PLEN0(tlen);
371
372                 dst += tlen;
373                 len -= tlen;
374
375                 /* update index */
376                 rx_idx = HSDMA_NEXT_DESC(rx_idx);
377         }
378
379         /* make sure desc and index all up to date */
380         wmb();
381         mtk_hsdma_write(hsdma, HSDMA_REG_TX_CTX, chan->tx_idx);
382
383         return 0;
384 }
385
386 static int gdma_next_desc(struct mtk_hsdma_chan *chan)
387 {
388         struct virt_dma_desc *vdesc;
389
390         vdesc = vchan_next_desc(&chan->vchan);
391         if (!vdesc) {
392                 chan->desc = NULL;
393                 return 0;
394         }
395         chan->desc = to_mtk_hsdma_desc(vdesc);
396         chan->next_sg = 0;
397
398         return 1;
399 }
400
401 static void mtk_hsdma_chan_done(struct mtk_hsdam_engine *hsdma,
402                                 struct mtk_hsdma_chan *chan)
403 {
404         struct mtk_hsdma_desc *desc;
405         int chan_issued;
406
407         chan_issued = 0;
408         spin_lock_bh(&chan->vchan.lock);
409         desc = chan->desc;
410         if (likely(desc)) {
411                 if (chan->next_sg == desc->num_sgs) {
412                         list_del(&desc->vdesc.node);
413                         vchan_cookie_complete(&desc->vdesc);
414                         chan_issued = gdma_next_desc(chan);
415                 }
416         } else {
417                 dev_dbg(hsdma->ddev.dev, "no desc to complete\n");
418         }
419
420         if (chan_issued)
421                 set_bit(chan->id, &hsdma->chan_issued);
422         spin_unlock_bh(&chan->vchan.lock);
423 }
424
425 static irqreturn_t mtk_hsdma_irq(int irq, void *devid)
426 {
427         struct mtk_hsdam_engine *hsdma = devid;
428         u32 status;
429
430         status = mtk_hsdma_read(hsdma, HSDMA_REG_INT_STATUS);
431         if (unlikely(!status))
432                 return IRQ_NONE;
433
434         if (likely(status & HSDMA_INT_RX_Q0))
435                 tasklet_schedule(&hsdma->task);
436         else
437                 dev_dbg(hsdma->ddev.dev, "unhandle irq status %08x\n", status);
438         /* clean intr bits */
439         mtk_hsdma_write(hsdma, HSDMA_REG_INT_STATUS, status);
440
441         return IRQ_HANDLED;
442 }
443
444 static void mtk_hsdma_issue_pending(struct dma_chan *c)
445 {
446         struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
447         struct mtk_hsdam_engine *hsdma = mtk_hsdma_chan_get_dev(chan);
448
449         spin_lock_bh(&chan->vchan.lock);
450         if (vchan_issue_pending(&chan->vchan) && !chan->desc) {
451                 if (gdma_next_desc(chan)) {
452                         set_bit(chan->id, &hsdma->chan_issued);
453                         tasklet_schedule(&hsdma->task);
454                 } else {
455                         dev_dbg(hsdma->ddev.dev, "no desc to issue\n");
456                 }
457         }
458         spin_unlock_bh(&chan->vchan.lock);
459 }
460
461 static struct dma_async_tx_descriptor *mtk_hsdma_prep_dma_memcpy(
462                 struct dma_chan *c, dma_addr_t dest, dma_addr_t src,
463                 size_t len, unsigned long flags)
464 {
465         struct mtk_hsdma_chan *chan = to_mtk_hsdma_chan(c);
466         struct mtk_hsdma_desc *desc;
467
468         if (len <= 0)
469                 return NULL;
470
471         desc = kzalloc(sizeof(*desc), GFP_ATOMIC);
472         if (!desc) {
473                 dev_err(c->device->dev, "alloc memcpy decs error\n");
474                 return NULL;
475         }
476
477         desc->sg[0].src_addr = src;
478         desc->sg[0].dst_addr = dest;
479         desc->sg[0].len = len;
480
481         return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
482 }
483
484 static enum dma_status mtk_hsdma_tx_status(struct dma_chan *c,
485                                            dma_cookie_t cookie,
486                                            struct dma_tx_state *state)
487 {
488         return dma_cookie_status(c, cookie, state);
489 }
490
491 static void mtk_hsdma_free_chan_resources(struct dma_chan *c)
492 {
493         vchan_free_chan_resources(to_virt_chan(c));
494 }
495
496 static void mtk_hsdma_desc_free(struct virt_dma_desc *vdesc)
497 {
498         kfree(container_of(vdesc, struct mtk_hsdma_desc, vdesc));
499 }
500
501 static void mtk_hsdma_tx(struct mtk_hsdam_engine *hsdma)
502 {
503         struct mtk_hsdma_chan *chan;
504
505         if (test_and_clear_bit(0, &hsdma->chan_issued)) {
506                 chan = &hsdma->chan[0];
507                 if (chan->desc)
508                         mtk_hsdma_start_transfer(hsdma, chan);
509                 else
510                         dev_dbg(hsdma->ddev.dev, "chan 0 no desc to issue\n");
511         }
512 }
513
514 static void mtk_hsdma_rx(struct mtk_hsdam_engine *hsdma)
515 {
516         struct mtk_hsdma_chan *chan;
517         int next_idx, drx_idx, cnt;
518
519         chan = &hsdma->chan[0];
520         next_idx = HSDMA_NEXT_DESC(chan->rx_idx);
521         drx_idx = mtk_hsdma_read(hsdma, HSDMA_REG_RX_DRX);
522
523         cnt = (drx_idx - next_idx) & HSDMA_DESCS_MASK;
524         if (!cnt)
525                 return;
526
527         chan->next_sg += cnt;
528         chan->rx_idx = (chan->rx_idx + cnt) & HSDMA_DESCS_MASK;
529
530         /* update rx crx */
531         wmb();
532         mtk_hsdma_write(hsdma, HSDMA_REG_RX_CRX, chan->rx_idx);
533
534         mtk_hsdma_chan_done(hsdma, chan);
535 }
536
537 static void mtk_hsdma_tasklet(unsigned long arg)
538 {
539         struct mtk_hsdam_engine *hsdma = (struct mtk_hsdam_engine *)arg;
540
541         mtk_hsdma_rx(hsdma);
542         mtk_hsdma_tx(hsdma);
543 }
544
545 static int mtk_hsdam_alloc_desc(struct mtk_hsdam_engine *hsdma,
546                                 struct mtk_hsdma_chan *chan)
547 {
548         int i;
549
550         chan->tx_ring = dma_alloc_coherent(hsdma->ddev.dev,
551                                            2 * HSDMA_DESCS_NUM *
552                                            sizeof(*chan->tx_ring),
553                         &chan->desc_addr, GFP_ATOMIC | __GFP_ZERO);
554         if (!chan->tx_ring)
555                 goto no_mem;
556
557         chan->rx_ring = &chan->tx_ring[HSDMA_DESCS_NUM];
558
559         /* init tx ring value */
560         for (i = 0; i < HSDMA_DESCS_NUM; i++)
561                 chan->tx_ring[i].flags = HSDMA_DESC_LS0 | HSDMA_DESC_DONE;
562
563         return 0;
564 no_mem:
565         return -ENOMEM;
566 }
567
568 static void mtk_hsdam_free_desc(struct mtk_hsdam_engine *hsdma,
569                                 struct mtk_hsdma_chan *chan)
570 {
571         if (chan->tx_ring) {
572                 dma_free_coherent(hsdma->ddev.dev,
573                                   2 * HSDMA_DESCS_NUM * sizeof(*chan->tx_ring),
574                                   chan->tx_ring, chan->desc_addr);
575                 chan->tx_ring = NULL;
576                 chan->rx_ring = NULL;
577         }
578 }
579
580 static int mtk_hsdma_init(struct mtk_hsdam_engine *hsdma)
581 {
582         struct mtk_hsdma_chan *chan;
583         int ret;
584         u32 reg;
585
586         /* init desc */
587         chan = &hsdma->chan[0];
588         ret = mtk_hsdam_alloc_desc(hsdma, chan);
589         if (ret)
590                 return ret;
591
592         /* tx */
593         mtk_hsdma_write(hsdma, HSDMA_REG_TX_BASE, chan->desc_addr);
594         mtk_hsdma_write(hsdma, HSDMA_REG_TX_CNT, HSDMA_DESCS_NUM);
595         /* rx */
596         mtk_hsdma_write(hsdma, HSDMA_REG_RX_BASE, chan->desc_addr +
597                         (sizeof(struct hsdma_desc) * HSDMA_DESCS_NUM));
598         mtk_hsdma_write(hsdma, HSDMA_REG_RX_CNT, HSDMA_DESCS_NUM);
599         /* reset */
600         mtk_hsdma_reset_chan(hsdma, chan);
601
602         /* enable rx intr */
603         mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, HSDMA_INT_RX_Q0);
604
605         /* enable dma */
606         mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, HSDMA_GLO_DEFAULT);
607
608         /* hardware info */
609         reg = mtk_hsdma_read(hsdma, HSDMA_REG_INFO);
610         dev_info(hsdma->ddev.dev, "rx: %d, tx: %d\n",
611                  (reg >> HSDMA_INFO_RX_SHIFT) & HSDMA_INFO_RX_MASK,
612                  (reg >> HSDMA_INFO_TX_SHIFT) & HSDMA_INFO_TX_MASK);
613
614         hsdma_dump_reg(hsdma);
615
616         return ret;
617 }
618
619 static void mtk_hsdma_uninit(struct mtk_hsdam_engine *hsdma)
620 {
621         struct mtk_hsdma_chan *chan;
622
623         /* disable dma */
624         mtk_hsdma_write(hsdma, HSDMA_REG_GLO_CFG, 0);
625
626         /* disable intr */
627         mtk_hsdma_write(hsdma, HSDMA_REG_INT_MASK, 0);
628
629         /* free desc */
630         chan = &hsdma->chan[0];
631         mtk_hsdam_free_desc(hsdma, chan);
632
633         /* tx */
634         mtk_hsdma_write(hsdma, HSDMA_REG_TX_BASE, 0);
635         mtk_hsdma_write(hsdma, HSDMA_REG_TX_CNT, 0);
636         /* rx */
637         mtk_hsdma_write(hsdma, HSDMA_REG_RX_BASE, 0);
638         mtk_hsdma_write(hsdma, HSDMA_REG_RX_CNT, 0);
639         /* reset */
640         mtk_hsdma_reset_chan(hsdma, chan);
641 }
642
643 static const struct of_device_id mtk_hsdma_of_match[] = {
644         { .compatible = "mediatek,mt7621-hsdma" },
645         { },
646 };
647
648 static int mtk_hsdma_probe(struct platform_device *pdev)
649 {
650         const struct of_device_id *match;
651         struct mtk_hsdma_chan *chan;
652         struct mtk_hsdam_engine *hsdma;
653         struct dma_device *dd;
654         int ret;
655         int irq;
656         void __iomem *base;
657
658         ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
659         if (ret)
660                 return ret;
661
662         match = of_match_device(mtk_hsdma_of_match, &pdev->dev);
663         if (!match)
664                 return -EINVAL;
665
666         hsdma = devm_kzalloc(&pdev->dev, sizeof(*hsdma), GFP_KERNEL);
667         if (!hsdma)
668                 return -EINVAL;
669
670         base = devm_platform_ioremap_resource(pdev, 0);
671         if (IS_ERR(base))
672                 return PTR_ERR(base);
673         hsdma->base = base + HSDMA_BASE_OFFSET;
674         tasklet_init(&hsdma->task, mtk_hsdma_tasklet, (unsigned long)hsdma);
675
676         irq = platform_get_irq(pdev, 0);
677         if (irq < 0)
678                 return -EINVAL;
679         ret = devm_request_irq(&pdev->dev, irq, mtk_hsdma_irq,
680                                0, dev_name(&pdev->dev), hsdma);
681         if (ret) {
682                 dev_err(&pdev->dev, "failed to request irq\n");
683                 return ret;
684         }
685
686         device_reset(&pdev->dev);
687
688         dd = &hsdma->ddev;
689         dma_cap_set(DMA_MEMCPY, dd->cap_mask);
690         dd->copy_align = HSDMA_ALIGN_SIZE;
691         dd->device_free_chan_resources = mtk_hsdma_free_chan_resources;
692         dd->device_prep_dma_memcpy = mtk_hsdma_prep_dma_memcpy;
693         dd->device_terminate_all = mtk_hsdma_terminate_all;
694         dd->device_tx_status = mtk_hsdma_tx_status;
695         dd->device_issue_pending = mtk_hsdma_issue_pending;
696         dd->dev = &pdev->dev;
697         dd->dev->dma_parms = &hsdma->dma_parms;
698         dma_set_max_seg_size(dd->dev, HSDMA_MAX_PLEN);
699         INIT_LIST_HEAD(&dd->channels);
700
701         chan = &hsdma->chan[0];
702         chan->id = 0;
703         chan->vchan.desc_free = mtk_hsdma_desc_free;
704         vchan_init(&chan->vchan, dd);
705
706         /* init hardware */
707         ret = mtk_hsdma_init(hsdma);
708         if (ret) {
709                 dev_err(&pdev->dev, "failed to alloc ring descs\n");
710                 return ret;
711         }
712
713         ret = dma_async_device_register(dd);
714         if (ret) {
715                 dev_err(&pdev->dev, "failed to register dma device\n");
716                 return ret;
717         }
718
719         ret = of_dma_controller_register(pdev->dev.of_node,
720                                          of_dma_xlate_by_chan_id, hsdma);
721         if (ret) {
722                 dev_err(&pdev->dev, "failed to register of dma controller\n");
723                 goto err_unregister;
724         }
725
726         platform_set_drvdata(pdev, hsdma);
727
728         return 0;
729
730 err_unregister:
731         dma_async_device_unregister(dd);
732         return ret;
733 }
734
735 static int mtk_hsdma_remove(struct platform_device *pdev)
736 {
737         struct mtk_hsdam_engine *hsdma = platform_get_drvdata(pdev);
738
739         mtk_hsdma_uninit(hsdma);
740
741         of_dma_controller_free(pdev->dev.of_node);
742         dma_async_device_unregister(&hsdma->ddev);
743
744         return 0;
745 }
746
747 static struct platform_driver mtk_hsdma_driver = {
748         .probe = mtk_hsdma_probe,
749         .remove = mtk_hsdma_remove,
750         .driver = {
751                 .name = "hsdma-mt7621",
752                 .of_match_table = mtk_hsdma_of_match,
753         },
754 };
755 module_platform_driver(mtk_hsdma_driver);
756
757 MODULE_AUTHOR("Michael Lee <igvtee@gmail.com>");
758 MODULE_DESCRIPTION("MTK HSDMA driver");
759 MODULE_LICENSE("GPL v2");