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1// SPDX-License-Identifier: GPL-2.0+
2//
3// Actions Semi Owl SoCs DMA driver
4//
5// Copyright (c) 2014 Actions Semi Inc.
6// Author: David Liu <liuwei@actions-semi.com>
7//
8// Copyright (c) 2018 Linaro Ltd.
9// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
10
11#include <linux/bitops.h>
12#include <linux/clk.h>
13#include <linux/delay.h>
14#include <linux/dmaengine.h>
15#include <linux/dma-mapping.h>
16#include <linux/dmapool.h>
17#include <linux/err.h>
18#include <linux/init.h>
19#include <linux/interrupt.h>
20#include <linux/io.h>
21#include <linux/mm.h>
22#include <linux/module.h>
23#include <linux/of.h>
24#include <linux/of_dma.h>
25#include <linux/platform_device.h>
26#include <linux/slab.h>
27#include "virt-dma.h"
28
29#define OWL_DMA_FRAME_MAX_LENGTH 0xfffff
30
31/* Global DMA Controller Registers */
32#define OWL_DMA_IRQ_PD0 0x00
33#define OWL_DMA_IRQ_PD1 0x04
34#define OWL_DMA_IRQ_PD2 0x08
35#define OWL_DMA_IRQ_PD3 0x0C
36#define OWL_DMA_IRQ_EN0 0x10
37#define OWL_DMA_IRQ_EN1 0x14
38#define OWL_DMA_IRQ_EN2 0x18
39#define OWL_DMA_IRQ_EN3 0x1C
40#define OWL_DMA_SECURE_ACCESS_CTL 0x20
41#define OWL_DMA_NIC_QOS 0x24
42#define OWL_DMA_DBGSEL 0x28
43#define OWL_DMA_IDLE_STAT 0x2C
44
45/* Channel Registers */
46#define OWL_DMA_CHAN_BASE(i) (0x100 + (i) * 0x100)
47#define OWL_DMAX_MODE 0x00
48#define OWL_DMAX_SOURCE 0x04
49#define OWL_DMAX_DESTINATION 0x08
50#define OWL_DMAX_FRAME_LEN 0x0C
51#define OWL_DMAX_FRAME_CNT 0x10
52#define OWL_DMAX_REMAIN_FRAME_CNT 0x14
53#define OWL_DMAX_REMAIN_CNT 0x18
54#define OWL_DMAX_SOURCE_STRIDE 0x1C
55#define OWL_DMAX_DESTINATION_STRIDE 0x20
56#define OWL_DMAX_START 0x24
57#define OWL_DMAX_PAUSE 0x28
58#define OWL_DMAX_CHAINED_CTL 0x2C
59#define OWL_DMAX_CONSTANT 0x30
60#define OWL_DMAX_LINKLIST_CTL 0x34
61#define OWL_DMAX_NEXT_DESCRIPTOR 0x38
62#define OWL_DMAX_CURRENT_DESCRIPTOR_NUM 0x3C
63#define OWL_DMAX_INT_CTL 0x40
64#define OWL_DMAX_INT_STATUS 0x44
65#define OWL_DMAX_CURRENT_SOURCE_POINTER 0x48
66#define OWL_DMAX_CURRENT_DESTINATION_POINTER 0x4C
67
68/* OWL_DMAX_MODE Bits */
69#define OWL_DMA_MODE_TS(x) (((x) & GENMASK(5, 0)) << 0)
70#define OWL_DMA_MODE_ST(x) (((x) & GENMASK(1, 0)) << 8)
71#define OWL_DMA_MODE_ST_DEV OWL_DMA_MODE_ST(0)
72#define OWL_DMA_MODE_ST_DCU OWL_DMA_MODE_ST(2)
73#define OWL_DMA_MODE_ST_SRAM OWL_DMA_MODE_ST(3)
74#define OWL_DMA_MODE_DT(x) (((x) & GENMASK(1, 0)) << 10)
75#define OWL_DMA_MODE_DT_DEV OWL_DMA_MODE_DT(0)
76#define OWL_DMA_MODE_DT_DCU OWL_DMA_MODE_DT(2)
77#define OWL_DMA_MODE_DT_SRAM OWL_DMA_MODE_DT(3)
78#define OWL_DMA_MODE_SAM(x) (((x) & GENMASK(1, 0)) << 16)
79#define OWL_DMA_MODE_SAM_CONST OWL_DMA_MODE_SAM(0)
80#define OWL_DMA_MODE_SAM_INC OWL_DMA_MODE_SAM(1)
81#define OWL_DMA_MODE_SAM_STRIDE OWL_DMA_MODE_SAM(2)
82#define OWL_DMA_MODE_DAM(x) (((x) & GENMASK(1, 0)) << 18)
83#define OWL_DMA_MODE_DAM_CONST OWL_DMA_MODE_DAM(0)
84#define OWL_DMA_MODE_DAM_INC OWL_DMA_MODE_DAM(1)
85#define OWL_DMA_MODE_DAM_STRIDE OWL_DMA_MODE_DAM(2)
86#define OWL_DMA_MODE_PW(x) (((x) & GENMASK(2, 0)) << 20)
87#define OWL_DMA_MODE_CB BIT(23)
88#define OWL_DMA_MODE_NDDBW(x) (((x) & 0x1) << 28)
89#define OWL_DMA_MODE_NDDBW_32BIT OWL_DMA_MODE_NDDBW(0)
90#define OWL_DMA_MODE_NDDBW_8BIT OWL_DMA_MODE_NDDBW(1)
91#define OWL_DMA_MODE_CFE BIT(29)
92#define OWL_DMA_MODE_LME BIT(30)
93#define OWL_DMA_MODE_CME BIT(31)
94
95/* OWL_DMAX_LINKLIST_CTL Bits */
96#define OWL_DMA_LLC_SAV(x) (((x) & GENMASK(1, 0)) << 8)
97#define OWL_DMA_LLC_SAV_INC OWL_DMA_LLC_SAV(0)
98#define OWL_DMA_LLC_SAV_LOAD_NEXT OWL_DMA_LLC_SAV(1)
99#define OWL_DMA_LLC_SAV_LOAD_PREV OWL_DMA_LLC_SAV(2)
100#define OWL_DMA_LLC_DAV(x) (((x) & GENMASK(1, 0)) << 10)
101#define OWL_DMA_LLC_DAV_INC OWL_DMA_LLC_DAV(0)
102#define OWL_DMA_LLC_DAV_LOAD_NEXT OWL_DMA_LLC_DAV(1)
103#define OWL_DMA_LLC_DAV_LOAD_PREV OWL_DMA_LLC_DAV(2)
104#define OWL_DMA_LLC_SUSPEND BIT(16)
105
106/* OWL_DMAX_INT_CTL Bits */
107#define OWL_DMA_INTCTL_BLOCK BIT(0)
108#define OWL_DMA_INTCTL_SUPER_BLOCK BIT(1)
109#define OWL_DMA_INTCTL_FRAME BIT(2)
110#define OWL_DMA_INTCTL_HALF_FRAME BIT(3)
111#define OWL_DMA_INTCTL_LAST_FRAME BIT(4)
112
113/* OWL_DMAX_INT_STATUS Bits */
114#define OWL_DMA_INTSTAT_BLOCK BIT(0)
115#define OWL_DMA_INTSTAT_SUPER_BLOCK BIT(1)
116#define OWL_DMA_INTSTAT_FRAME BIT(2)
117#define OWL_DMA_INTSTAT_HALF_FRAME BIT(3)
118#define OWL_DMA_INTSTAT_LAST_FRAME BIT(4)
119
120/* Pack shift and newshift in a single word */
121#define BIT_FIELD(val, width, shift, newshift) \
122 ((((val) >> (shift)) & ((BIT(width)) - 1)) << (newshift))
123
124/* Frame count value is fixed as 1 */
125#define FCNT_VAL 0x1
126
127/**
128 * enum owl_dmadesc_offsets - Describe DMA descriptor, hardware link
129 * list for dma transfer
130 * @OWL_DMADESC_NEXT_LLI: physical address of the next link list
131 * @OWL_DMADESC_SADDR: source physical address
132 * @OWL_DMADESC_DADDR: destination physical address
133 * @OWL_DMADESC_FLEN: frame length
134 * @OWL_DMADESC_SRC_STRIDE: source stride
135 * @OWL_DMADESC_DST_STRIDE: destination stride
136 * @OWL_DMADESC_CTRLA: dma_mode and linklist ctrl config
137 * @OWL_DMADESC_CTRLB: interrupt config
138 * @OWL_DMADESC_CONST_NUM: data for constant fill
139 * @OWL_DMADESC_SIZE: max size of this enum
140 */
141enum owl_dmadesc_offsets {
142 OWL_DMADESC_NEXT_LLI = 0,
143 OWL_DMADESC_SADDR,
144 OWL_DMADESC_DADDR,
145 OWL_DMADESC_FLEN,
146 OWL_DMADESC_SRC_STRIDE,
147 OWL_DMADESC_DST_STRIDE,
148 OWL_DMADESC_CTRLA,
149 OWL_DMADESC_CTRLB,
150 OWL_DMADESC_CONST_NUM,
151 OWL_DMADESC_SIZE
152};
153
154enum owl_dma_id {
155 S900_DMA,
156 S700_DMA,
157};
158
159/**
160 * struct owl_dma_lli - Link list for dma transfer
161 * @hw: hardware link list
162 * @phys: physical address of hardware link list
163 * @node: node for txd's lli_list
164 */
165struct owl_dma_lli {
166 u32 hw[OWL_DMADESC_SIZE];
167 dma_addr_t phys;
168 struct list_head node;
169};
170
171/**
172 * struct owl_dma_txd - Wrapper for struct dma_async_tx_descriptor
173 * @vd: virtual DMA descriptor
174 * @lli_list: link list of lli nodes
175 * @cyclic: flag to indicate cyclic transfers
176 */
177struct owl_dma_txd {
178 struct virt_dma_desc vd;
179 struct list_head lli_list;
180 bool cyclic;
181};
182
183/**
184 * struct owl_dma_pchan - Holder for the physical channels
185 * @id: physical index to this channel
186 * @base: virtual memory base for the dma channel
187 * @vchan: the virtual channel currently being served by this physical channel
188 */
189struct owl_dma_pchan {
190 u32 id;
191 void __iomem *base;
192 struct owl_dma_vchan *vchan;
193};
194
195/**
196 * struct owl_dma_vchan - Wrapper for DMA ENGINE channel
197 * @vc: wrapped virtual channel
198 * @pchan: the physical channel utilized by this channel
199 * @txd: active transaction on this channel
200 * @cfg: slave configuration for this channel
201 * @drq: physical DMA request ID for this channel
202 */
203struct owl_dma_vchan {
204 struct virt_dma_chan vc;
205 struct owl_dma_pchan *pchan;
206 struct owl_dma_txd *txd;
207 struct dma_slave_config cfg;
208 u8 drq;
209};
210
211/**
212 * struct owl_dma - Holder for the Owl DMA controller
213 * @dma: dma engine for this instance
214 * @base: virtual memory base for the DMA controller
215 * @clk: clock for the DMA controller
216 * @lock: a lock to use when change DMA controller global register
217 * @lli_pool: a pool for the LLI descriptors
218 * @irq: interrupt ID for the DMA controller
219 * @nr_pchans: the number of physical channels
220 * @pchans: array of data for the physical channels
221 * @nr_vchans: the number of physical channels
222 * @vchans: array of data for the physical channels
223 * @devid: device id based on OWL SoC
224 */
225struct owl_dma {
226 struct dma_device dma;
227 void __iomem *base;
228 struct clk *clk;
229 spinlock_t lock;
230 struct dma_pool *lli_pool;
231 int irq;
232
233 unsigned int nr_pchans;
234 struct owl_dma_pchan *pchans;
235
236 unsigned int nr_vchans;
237 struct owl_dma_vchan *vchans;
238 enum owl_dma_id devid;
239};
240
241static void pchan_update(struct owl_dma_pchan *pchan, u32 reg,
242 u32 val, bool state)
243{
244 u32 regval;
245
246 regval = readl(pchan->base + reg);
247
248 if (state)
249 regval |= val;
250 else
251 regval &= ~val;
252
253 writel(val, pchan->base + reg);
254}
255
256static void pchan_writel(struct owl_dma_pchan *pchan, u32 reg, u32 data)
257{
258 writel(data, pchan->base + reg);
259}
260
261static u32 pchan_readl(struct owl_dma_pchan *pchan, u32 reg)
262{
263 return readl(pchan->base + reg);
264}
265
266static void dma_update(struct owl_dma *od, u32 reg, u32 val, bool state)
267{
268 u32 regval;
269
270 regval = readl(od->base + reg);
271
272 if (state)
273 regval |= val;
274 else
275 regval &= ~val;
276
277 writel(val, od->base + reg);
278}
279
280static void dma_writel(struct owl_dma *od, u32 reg, u32 data)
281{
282 writel(data, od->base + reg);
283}
284
285static u32 dma_readl(struct owl_dma *od, u32 reg)
286{
287 return readl(od->base + reg);
288}
289
290static inline struct owl_dma *to_owl_dma(struct dma_device *dd)
291{
292 return container_of(dd, struct owl_dma, dma);
293}
294
295static struct device *chan2dev(struct dma_chan *chan)
296{
297 return &chan->dev->device;
298}
299
300static inline struct owl_dma_vchan *to_owl_vchan(struct dma_chan *chan)
301{
302 return container_of(chan, struct owl_dma_vchan, vc.chan);
303}
304
305static inline struct owl_dma_txd *to_owl_txd(struct dma_async_tx_descriptor *tx)
306{
307 return container_of(tx, struct owl_dma_txd, vd.tx);
308}
309
310static inline u32 llc_hw_ctrla(u32 mode, u32 llc_ctl)
311{
312 u32 ctl;
313
314 ctl = BIT_FIELD(mode, 4, 28, 28) |
315 BIT_FIELD(mode, 8, 16, 20) |
316 BIT_FIELD(mode, 4, 8, 16) |
317 BIT_FIELD(mode, 6, 0, 10) |
318 BIT_FIELD(llc_ctl, 2, 10, 8) |
319 BIT_FIELD(llc_ctl, 2, 8, 6);
320
321 return ctl;
322}
323
324static inline u32 llc_hw_ctrlb(u32 int_ctl)
325{
326 u32 ctl;
327
328 /*
329 * Irrespective of the SoC, ctrlb value starts filling from
330 * bit 18.
331 */
332 ctl = BIT_FIELD(int_ctl, 7, 0, 18);
333
334 return ctl;
335}
336
337static u32 llc_hw_flen(struct owl_dma_lli *lli)
338{
339 return lli->hw[OWL_DMADESC_FLEN] & GENMASK(19, 0);
340}
341
342static void owl_dma_free_lli(struct owl_dma *od,
343 struct owl_dma_lli *lli)
344{
345 list_del(&lli->node);
346 dma_pool_free(od->lli_pool, lli, lli->phys);
347}
348
349static struct owl_dma_lli *owl_dma_alloc_lli(struct owl_dma *od)
350{
351 struct owl_dma_lli *lli;
352 dma_addr_t phys;
353
354 lli = dma_pool_alloc(od->lli_pool, GFP_NOWAIT, &phys);
355 if (!lli)
356 return NULL;
357
358 INIT_LIST_HEAD(&lli->node);
359 lli->phys = phys;
360
361 return lli;
362}
363
364static struct owl_dma_lli *owl_dma_add_lli(struct owl_dma_txd *txd,
365 struct owl_dma_lli *prev,
366 struct owl_dma_lli *next,
367 bool is_cyclic)
368{
369 if (!is_cyclic)
370 list_add_tail(&next->node, &txd->lli_list);
371
372 if (prev) {
373 prev->hw[OWL_DMADESC_NEXT_LLI] = next->phys;
374 prev->hw[OWL_DMADESC_CTRLA] |=
375 llc_hw_ctrla(OWL_DMA_MODE_LME, 0);
376 }
377
378 return next;
379}
380
381static inline int owl_dma_cfg_lli(struct owl_dma_vchan *vchan,
382 struct owl_dma_lli *lli,
383 dma_addr_t src, dma_addr_t dst,
384 u32 len, enum dma_transfer_direction dir,
385 struct dma_slave_config *sconfig,
386 bool is_cyclic)
387{
388 struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
389 u32 mode, ctrlb;
390
391 mode = OWL_DMA_MODE_PW(0);
392
393 switch (dir) {
394 case DMA_MEM_TO_MEM:
395 mode |= OWL_DMA_MODE_TS(0) | OWL_DMA_MODE_ST_DCU |
396 OWL_DMA_MODE_DT_DCU | OWL_DMA_MODE_SAM_INC |
397 OWL_DMA_MODE_DAM_INC;
398
399 break;
400 case DMA_MEM_TO_DEV:
401 mode |= OWL_DMA_MODE_TS(vchan->drq)
402 | OWL_DMA_MODE_ST_DCU | OWL_DMA_MODE_DT_DEV
403 | OWL_DMA_MODE_SAM_INC | OWL_DMA_MODE_DAM_CONST;
404
405 /*
406 * Hardware only supports 32bit and 8bit buswidth. Since the
407 * default is 32bit, select 8bit only when requested.
408 */
409 if (sconfig->dst_addr_width == DMA_SLAVE_BUSWIDTH_1_BYTE)
410 mode |= OWL_DMA_MODE_NDDBW_8BIT;
411
412 break;
413 case DMA_DEV_TO_MEM:
414 mode |= OWL_DMA_MODE_TS(vchan->drq)
415 | OWL_DMA_MODE_ST_DEV | OWL_DMA_MODE_DT_DCU
416 | OWL_DMA_MODE_SAM_CONST | OWL_DMA_MODE_DAM_INC;
417
418 /*
419 * Hardware only supports 32bit and 8bit buswidth. Since the
420 * default is 32bit, select 8bit only when requested.
421 */
422 if (sconfig->src_addr_width == DMA_SLAVE_BUSWIDTH_1_BYTE)
423 mode |= OWL_DMA_MODE_NDDBW_8BIT;
424
425 break;
426 default:
427 return -EINVAL;
428 }
429
430 lli->hw[OWL_DMADESC_CTRLA] = llc_hw_ctrla(mode,
431 OWL_DMA_LLC_SAV_LOAD_NEXT |
432 OWL_DMA_LLC_DAV_LOAD_NEXT);
433
434 if (is_cyclic)
435 ctrlb = llc_hw_ctrlb(OWL_DMA_INTCTL_BLOCK);
436 else
437 ctrlb = llc_hw_ctrlb(OWL_DMA_INTCTL_SUPER_BLOCK);
438
439 lli->hw[OWL_DMADESC_NEXT_LLI] = 0; /* One link list by default */
440 lli->hw[OWL_DMADESC_SADDR] = src;
441 lli->hw[OWL_DMADESC_DADDR] = dst;
442 lli->hw[OWL_DMADESC_SRC_STRIDE] = 0;
443 lli->hw[OWL_DMADESC_DST_STRIDE] = 0;
444
445 if (od->devid == S700_DMA) {
446 /* Max frame length is 1MB */
447 lli->hw[OWL_DMADESC_FLEN] = len;
448 /*
449 * On S700, word starts from offset 0x1C is shared between
450 * frame count and ctrlb, where first 12 bits are for frame
451 * count and rest of 20 bits are for ctrlb.
452 */
453 lli->hw[OWL_DMADESC_CTRLB] = FCNT_VAL | ctrlb;
454 } else {
455 /*
456 * On S900, word starts from offset 0xC is shared between
457 * frame length (max frame length is 1MB) and frame count,
458 * where first 20 bits are for frame length and rest of
459 * 12 bits are for frame count.
460 */
461 lli->hw[OWL_DMADESC_FLEN] = len | FCNT_VAL << 20;
462 lli->hw[OWL_DMADESC_CTRLB] = ctrlb;
463 }
464
465 return 0;
466}
467
468static struct owl_dma_pchan *owl_dma_get_pchan(struct owl_dma *od,
469 struct owl_dma_vchan *vchan)
470{
471 struct owl_dma_pchan *pchan = NULL;
472 unsigned long flags;
473 int i;
474
475 for (i = 0; i < od->nr_pchans; i++) {
476 pchan = &od->pchans[i];
477
478 spin_lock_irqsave(&od->lock, flags);
479 if (!pchan->vchan) {
480 pchan->vchan = vchan;
481 spin_unlock_irqrestore(&od->lock, flags);
482 break;
483 }
484
485 spin_unlock_irqrestore(&od->lock, flags);
486 }
487
488 return pchan;
489}
490
491static int owl_dma_pchan_busy(struct owl_dma *od, struct owl_dma_pchan *pchan)
492{
493 unsigned int val;
494
495 val = dma_readl(od, OWL_DMA_IDLE_STAT);
496
497 return !(val & (1 << pchan->id));
498}
499
500static void owl_dma_terminate_pchan(struct owl_dma *od,
501 struct owl_dma_pchan *pchan)
502{
503 unsigned long flags;
504 u32 irq_pd;
505
506 pchan_writel(pchan, OWL_DMAX_START, 0);
507 pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
508
509 spin_lock_irqsave(&od->lock, flags);
510 dma_update(od, OWL_DMA_IRQ_EN0, (1 << pchan->id), false);
511
512 irq_pd = dma_readl(od, OWL_DMA_IRQ_PD0);
513 if (irq_pd & (1 << pchan->id)) {
514 dev_warn(od->dma.dev,
515 "terminating pchan %d that still has pending irq\n",
516 pchan->id);
517 dma_writel(od, OWL_DMA_IRQ_PD0, (1 << pchan->id));
518 }
519
520 pchan->vchan = NULL;
521
522 spin_unlock_irqrestore(&od->lock, flags);
523}
524
525static void owl_dma_pause_pchan(struct owl_dma_pchan *pchan)
526{
527 pchan_writel(pchan, 1, OWL_DMAX_PAUSE);
528}
529
530static void owl_dma_resume_pchan(struct owl_dma_pchan *pchan)
531{
532 pchan_writel(pchan, 0, OWL_DMAX_PAUSE);
533}
534
535static int owl_dma_start_next_txd(struct owl_dma_vchan *vchan)
536{
537 struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
538 struct virt_dma_desc *vd = vchan_next_desc(&vchan->vc);
539 struct owl_dma_pchan *pchan = vchan->pchan;
540 struct owl_dma_txd *txd = to_owl_txd(&vd->tx);
541 struct owl_dma_lli *lli;
542 unsigned long flags;
543 u32 int_ctl;
544
545 list_del(&vd->node);
546
547 vchan->txd = txd;
548
549 /* Wait for channel inactive */
550 while (owl_dma_pchan_busy(od, pchan))
551 cpu_relax();
552
553 lli = list_first_entry(&txd->lli_list,
554 struct owl_dma_lli, node);
555
556 if (txd->cyclic)
557 int_ctl = OWL_DMA_INTCTL_BLOCK;
558 else
559 int_ctl = OWL_DMA_INTCTL_SUPER_BLOCK;
560
561 pchan_writel(pchan, OWL_DMAX_MODE, OWL_DMA_MODE_LME);
562 pchan_writel(pchan, OWL_DMAX_LINKLIST_CTL,
563 OWL_DMA_LLC_SAV_LOAD_NEXT | OWL_DMA_LLC_DAV_LOAD_NEXT);
564 pchan_writel(pchan, OWL_DMAX_NEXT_DESCRIPTOR, lli->phys);
565 pchan_writel(pchan, OWL_DMAX_INT_CTL, int_ctl);
566
567 /* Clear IRQ status for this pchan */
568 pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
569
570 spin_lock_irqsave(&od->lock, flags);
571
572 dma_update(od, OWL_DMA_IRQ_EN0, (1 << pchan->id), true);
573
574 spin_unlock_irqrestore(&od->lock, flags);
575
576 dev_dbg(chan2dev(&vchan->vc.chan), "starting pchan %d\n", pchan->id);
577
578 /* Start DMA transfer for this pchan */
579 pchan_writel(pchan, OWL_DMAX_START, 0x1);
580
581 return 0;
582}
583
584static void owl_dma_phy_free(struct owl_dma *od, struct owl_dma_vchan *vchan)
585{
586 /* Ensure that the physical channel is stopped */
587 owl_dma_terminate_pchan(od, vchan->pchan);
588
589 vchan->pchan = NULL;
590}
591
592static irqreturn_t owl_dma_interrupt(int irq, void *dev_id)
593{
594 struct owl_dma *od = dev_id;
595 struct owl_dma_vchan *vchan;
596 struct owl_dma_pchan *pchan;
597 unsigned long pending;
598 int i;
599 unsigned int global_irq_pending, chan_irq_pending;
600
601 spin_lock(&od->lock);
602
603 pending = dma_readl(od, OWL_DMA_IRQ_PD0);
604
605 /* Clear IRQ status for each pchan */
606 for_each_set_bit(i, &pending, od->nr_pchans) {
607 pchan = &od->pchans[i];
608 pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
609 }
610
611 /* Clear pending IRQ */
612 dma_writel(od, OWL_DMA_IRQ_PD0, pending);
613
614 /* Check missed pending IRQ */
615 for (i = 0; i < od->nr_pchans; i++) {
616 pchan = &od->pchans[i];
617 chan_irq_pending = pchan_readl(pchan, OWL_DMAX_INT_CTL) &
618 pchan_readl(pchan, OWL_DMAX_INT_STATUS);
619
620 /* Dummy read to ensure OWL_DMA_IRQ_PD0 value is updated */
621 dma_readl(od, OWL_DMA_IRQ_PD0);
622
623 global_irq_pending = dma_readl(od, OWL_DMA_IRQ_PD0);
624
625 if (chan_irq_pending && !(global_irq_pending & BIT(i))) {
626 dev_dbg(od->dma.dev,
627 "global and channel IRQ pending match err\n");
628
629 /* Clear IRQ status for this pchan */
630 pchan_update(pchan, OWL_DMAX_INT_STATUS,
631 0xff, false);
632
633 /* Update global IRQ pending */
634 pending |= BIT(i);
635 }
636 }
637
638 spin_unlock(&od->lock);
639
640 for_each_set_bit(i, &pending, od->nr_pchans) {
641 struct owl_dma_txd *txd;
642
643 pchan = &od->pchans[i];
644
645 vchan = pchan->vchan;
646 if (!vchan) {
647 dev_warn(od->dma.dev, "no vchan attached on pchan %d\n",
648 pchan->id);
649 continue;
650 }
651
652 spin_lock(&vchan->vc.lock);
653
654 txd = vchan->txd;
655 if (txd) {
656 vchan->txd = NULL;
657
658 vchan_cookie_complete(&txd->vd);
659
660 /*
661 * Start the next descriptor (if any),
662 * otherwise free this channel.
663 */
664 if (vchan_next_desc(&vchan->vc))
665 owl_dma_start_next_txd(vchan);
666 else
667 owl_dma_phy_free(od, vchan);
668 }
669
670 spin_unlock(&vchan->vc.lock);
671 }
672
673 return IRQ_HANDLED;
674}
675
676static void owl_dma_free_txd(struct owl_dma *od, struct owl_dma_txd *txd)
677{
678 struct owl_dma_lli *lli, *_lli;
679
680 if (unlikely(!txd))
681 return;
682
683 list_for_each_entry_safe(lli, _lli, &txd->lli_list, node)
684 owl_dma_free_lli(od, lli);
685
686 kfree(txd);
687}
688
689static void owl_dma_desc_free(struct virt_dma_desc *vd)
690{
691 struct owl_dma *od = to_owl_dma(vd->tx.chan->device);
692 struct owl_dma_txd *txd = to_owl_txd(&vd->tx);
693
694 owl_dma_free_txd(od, txd);
695}
696
697static int owl_dma_terminate_all(struct dma_chan *chan)
698{
699 struct owl_dma *od = to_owl_dma(chan->device);
700 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
701 unsigned long flags;
702 LIST_HEAD(head);
703
704 spin_lock_irqsave(&vchan->vc.lock, flags);
705
706 if (vchan->pchan)
707 owl_dma_phy_free(od, vchan);
708
709 if (vchan->txd) {
710 owl_dma_desc_free(&vchan->txd->vd);
711 vchan->txd = NULL;
712 }
713
714 vchan_get_all_descriptors(&vchan->vc, &head);
715
716 spin_unlock_irqrestore(&vchan->vc.lock, flags);
717
718 vchan_dma_desc_free_list(&vchan->vc, &head);
719
720 return 0;
721}
722
723static int owl_dma_config(struct dma_chan *chan,
724 struct dma_slave_config *config)
725{
726 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
727
728 /* Reject definitely invalid configurations */
729 if (config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
730 config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
731 return -EINVAL;
732
733 memcpy(&vchan->cfg, config, sizeof(struct dma_slave_config));
734
735 return 0;
736}
737
738static int owl_dma_pause(struct dma_chan *chan)
739{
740 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
741 unsigned long flags;
742
743 spin_lock_irqsave(&vchan->vc.lock, flags);
744
745 owl_dma_pause_pchan(vchan->pchan);
746
747 spin_unlock_irqrestore(&vchan->vc.lock, flags);
748
749 return 0;
750}
751
752static int owl_dma_resume(struct dma_chan *chan)
753{
754 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
755 unsigned long flags;
756
757 if (!vchan->pchan && !vchan->txd)
758 return 0;
759
760 dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc);
761
762 spin_lock_irqsave(&vchan->vc.lock, flags);
763
764 owl_dma_resume_pchan(vchan->pchan);
765
766 spin_unlock_irqrestore(&vchan->vc.lock, flags);
767
768 return 0;
769}
770
771static u32 owl_dma_getbytes_chan(struct owl_dma_vchan *vchan)
772{
773 struct owl_dma_pchan *pchan;
774 struct owl_dma_txd *txd;
775 struct owl_dma_lli *lli;
776 unsigned int next_lli_phy;
777 size_t bytes;
778
779 pchan = vchan->pchan;
780 txd = vchan->txd;
781
782 if (!pchan || !txd)
783 return 0;
784
785 /* Get remain count of current node in link list */
786 bytes = pchan_readl(pchan, OWL_DMAX_REMAIN_CNT);
787
788 /* Loop through the preceding nodes to get total remaining bytes */
789 if (pchan_readl(pchan, OWL_DMAX_MODE) & OWL_DMA_MODE_LME) {
790 next_lli_phy = pchan_readl(pchan, OWL_DMAX_NEXT_DESCRIPTOR);
791 list_for_each_entry(lli, &txd->lli_list, node) {
792 /* Start from the next active node */
793 if (lli->phys == next_lli_phy) {
794 list_for_each_entry(lli, &txd->lli_list, node)
795 bytes += llc_hw_flen(lli);
796 break;
797 }
798 }
799 }
800
801 return bytes;
802}
803
804static enum dma_status owl_dma_tx_status(struct dma_chan *chan,
805 dma_cookie_t cookie,
806 struct dma_tx_state *state)
807{
808 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
809 struct owl_dma_lli *lli;
810 struct virt_dma_desc *vd;
811 struct owl_dma_txd *txd;
812 enum dma_status ret;
813 unsigned long flags;
814 size_t bytes = 0;
815
816 ret = dma_cookie_status(chan, cookie, state);
817 if (ret == DMA_COMPLETE || !state)
818 return ret;
819
820 spin_lock_irqsave(&vchan->vc.lock, flags);
821
822 vd = vchan_find_desc(&vchan->vc, cookie);
823 if (vd) {
824 txd = to_owl_txd(&vd->tx);
825 list_for_each_entry(lli, &txd->lli_list, node)
826 bytes += llc_hw_flen(lli);
827 } else {
828 bytes = owl_dma_getbytes_chan(vchan);
829 }
830
831 spin_unlock_irqrestore(&vchan->vc.lock, flags);
832
833 dma_set_residue(state, bytes);
834
835 return ret;
836}
837
838static void owl_dma_phy_alloc_and_start(struct owl_dma_vchan *vchan)
839{
840 struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
841 struct owl_dma_pchan *pchan;
842
843 pchan = owl_dma_get_pchan(od, vchan);
844 if (!pchan)
845 return;
846
847 dev_dbg(od->dma.dev, "allocated pchan %d\n", pchan->id);
848
849 vchan->pchan = pchan;
850 owl_dma_start_next_txd(vchan);
851}
852
853static void owl_dma_issue_pending(struct dma_chan *chan)
854{
855 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
856 unsigned long flags;
857
858 spin_lock_irqsave(&vchan->vc.lock, flags);
859 if (vchan_issue_pending(&vchan->vc)) {
860 if (!vchan->pchan)
861 owl_dma_phy_alloc_and_start(vchan);
862 }
863 spin_unlock_irqrestore(&vchan->vc.lock, flags);
864}
865
866static struct dma_async_tx_descriptor
867 *owl_dma_prep_memcpy(struct dma_chan *chan,
868 dma_addr_t dst, dma_addr_t src,
869 size_t len, unsigned long flags)
870{
871 struct owl_dma *od = to_owl_dma(chan->device);
872 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
873 struct owl_dma_txd *txd;
874 struct owl_dma_lli *lli, *prev = NULL;
875 size_t offset, bytes;
876 int ret;
877
878 if (!len)
879 return NULL;
880
881 txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
882 if (!txd)
883 return NULL;
884
885 INIT_LIST_HEAD(&txd->lli_list);
886
887 /* Process the transfer as frame by frame */
888 for (offset = 0; offset < len; offset += bytes) {
889 lli = owl_dma_alloc_lli(od);
890 if (!lli) {
891 dev_warn(chan2dev(chan), "failed to allocate lli\n");
892 goto err_txd_free;
893 }
894
895 bytes = min_t(size_t, (len - offset), OWL_DMA_FRAME_MAX_LENGTH);
896
897 ret = owl_dma_cfg_lli(vchan, lli, src + offset, dst + offset,
898 bytes, DMA_MEM_TO_MEM,
899 &vchan->cfg, txd->cyclic);
900 if (ret) {
901 dev_warn(chan2dev(chan), "failed to config lli\n");
902 goto err_txd_free;
903 }
904
905 prev = owl_dma_add_lli(txd, prev, lli, false);
906 }
907
908 return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
909
910err_txd_free:
911 owl_dma_free_txd(od, txd);
912 return NULL;
913}
914
915static struct dma_async_tx_descriptor
916 *owl_dma_prep_slave_sg(struct dma_chan *chan,
917 struct scatterlist *sgl,
918 unsigned int sg_len,
919 enum dma_transfer_direction dir,
920 unsigned long flags, void *context)
921{
922 struct owl_dma *od = to_owl_dma(chan->device);
923 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
924 struct dma_slave_config *sconfig = &vchan->cfg;
925 struct owl_dma_txd *txd;
926 struct owl_dma_lli *lli, *prev = NULL;
927 struct scatterlist *sg;
928 dma_addr_t addr, src = 0, dst = 0;
929 size_t len;
930 int ret, i;
931
932 txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
933 if (!txd)
934 return NULL;
935
936 INIT_LIST_HEAD(&txd->lli_list);
937
938 for_each_sg(sgl, sg, sg_len, i) {
939 addr = sg_dma_address(sg);
940 len = sg_dma_len(sg);
941
942 if (len > OWL_DMA_FRAME_MAX_LENGTH) {
943 dev_err(od->dma.dev,
944 "frame length exceeds max supported length");
945 goto err_txd_free;
946 }
947
948 lli = owl_dma_alloc_lli(od);
949 if (!lli) {
950 dev_err(chan2dev(chan), "failed to allocate lli");
951 goto err_txd_free;
952 }
953
954 if (dir == DMA_MEM_TO_DEV) {
955 src = addr;
956 dst = sconfig->dst_addr;
957 } else {
958 src = sconfig->src_addr;
959 dst = addr;
960 }
961
962 ret = owl_dma_cfg_lli(vchan, lli, src, dst, len, dir, sconfig,
963 txd->cyclic);
964 if (ret) {
965 dev_warn(chan2dev(chan), "failed to config lli");
966 goto err_txd_free;
967 }
968
969 prev = owl_dma_add_lli(txd, prev, lli, false);
970 }
971
972 return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
973
974err_txd_free:
975 owl_dma_free_txd(od, txd);
976
977 return NULL;
978}
979
980static struct dma_async_tx_descriptor
981 *owl_prep_dma_cyclic(struct dma_chan *chan,
982 dma_addr_t buf_addr, size_t buf_len,
983 size_t period_len,
984 enum dma_transfer_direction dir,
985 unsigned long flags)
986{
987 struct owl_dma *od = to_owl_dma(chan->device);
988 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
989 struct dma_slave_config *sconfig = &vchan->cfg;
990 struct owl_dma_txd *txd;
991 struct owl_dma_lli *lli, *prev = NULL, *first = NULL;
992 dma_addr_t src = 0, dst = 0;
993 unsigned int periods = buf_len / period_len;
994 int ret, i;
995
996 txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
997 if (!txd)
998 return NULL;
999
1000 INIT_LIST_HEAD(&txd->lli_list);
1001 txd->cyclic = true;
1002
1003 for (i = 0; i < periods; i++) {
1004 lli = owl_dma_alloc_lli(od);
1005 if (!lli) {
1006 dev_warn(chan2dev(chan), "failed to allocate lli");
1007 goto err_txd_free;
1008 }
1009
1010 if (dir == DMA_MEM_TO_DEV) {
1011 src = buf_addr + (period_len * i);
1012 dst = sconfig->dst_addr;
1013 } else if (dir == DMA_DEV_TO_MEM) {
1014 src = sconfig->src_addr;
1015 dst = buf_addr + (period_len * i);
1016 }
1017
1018 ret = owl_dma_cfg_lli(vchan, lli, src, dst, period_len,
1019 dir, sconfig, txd->cyclic);
1020 if (ret) {
1021 dev_warn(chan2dev(chan), "failed to config lli");
1022 goto err_txd_free;
1023 }
1024
1025 if (!first)
1026 first = lli;
1027
1028 prev = owl_dma_add_lli(txd, prev, lli, false);
1029 }
1030
1031 /* close the cyclic list */
1032 owl_dma_add_lli(txd, prev, first, true);
1033
1034 return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
1035
1036err_txd_free:
1037 owl_dma_free_txd(od, txd);
1038
1039 return NULL;
1040}
1041
1042static void owl_dma_free_chan_resources(struct dma_chan *chan)
1043{
1044 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
1045
1046 /* Ensure all queued descriptors are freed */
1047 vchan_free_chan_resources(&vchan->vc);
1048}
1049
1050static inline void owl_dma_free(struct owl_dma *od)
1051{
1052 struct owl_dma_vchan *vchan = NULL;
1053 struct owl_dma_vchan *next;
1054
1055 list_for_each_entry_safe(vchan,
1056 next, &od->dma.channels, vc.chan.device_node) {
1057 list_del(&vchan->vc.chan.device_node);
1058 tasklet_kill(&vchan->vc.task);
1059 }
1060}
1061
1062static struct dma_chan *owl_dma_of_xlate(struct of_phandle_args *dma_spec,
1063 struct of_dma *ofdma)
1064{
1065 struct owl_dma *od = ofdma->of_dma_data;
1066 struct owl_dma_vchan *vchan;
1067 struct dma_chan *chan;
1068 u8 drq = dma_spec->args[0];
1069
1070 if (drq > od->nr_vchans)
1071 return NULL;
1072
1073 chan = dma_get_any_slave_channel(&od->dma);
1074 if (!chan)
1075 return NULL;
1076
1077 vchan = to_owl_vchan(chan);
1078 vchan->drq = drq;
1079
1080 return chan;
1081}
1082
1083static const struct of_device_id owl_dma_match[] = {
1084 { .compatible = "actions,s500-dma", .data = (void *)S900_DMA,},
1085 { .compatible = "actions,s700-dma", .data = (void *)S700_DMA,},
1086 { .compatible = "actions,s900-dma", .data = (void *)S900_DMA,},
1087 { /* sentinel */ },
1088};
1089MODULE_DEVICE_TABLE(of, owl_dma_match);
1090
1091static int owl_dma_probe(struct platform_device *pdev)
1092{
1093 struct device_node *np = pdev->dev.of_node;
1094 struct owl_dma *od;
1095 int ret, i, nr_channels, nr_requests;
1096
1097 od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
1098 if (!od)
1099 return -ENOMEM;
1100
1101 od->base = devm_platform_ioremap_resource(pdev, 0);
1102 if (IS_ERR(od->base))
1103 return PTR_ERR(od->base);
1104
1105 ret = of_property_read_u32(np, "dma-channels", &nr_channels);
1106 if (ret) {
1107 dev_err(&pdev->dev, "can't get dma-channels\n");
1108 return ret;
1109 }
1110
1111 ret = of_property_read_u32(np, "dma-requests", &nr_requests);
1112 if (ret) {
1113 dev_err(&pdev->dev, "can't get dma-requests\n");
1114 return ret;
1115 }
1116
1117 dev_info(&pdev->dev, "dma-channels %d, dma-requests %d\n",
1118 nr_channels, nr_requests);
1119
1120 od->devid = (uintptr_t)of_device_get_match_data(&pdev->dev);
1121
1122 od->nr_pchans = nr_channels;
1123 od->nr_vchans = nr_requests;
1124
1125 pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
1126
1127 platform_set_drvdata(pdev, od);
1128 spin_lock_init(&od->lock);
1129
1130 dma_cap_set(DMA_MEMCPY, od->dma.cap_mask);
1131 dma_cap_set(DMA_SLAVE, od->dma.cap_mask);
1132 dma_cap_set(DMA_CYCLIC, od->dma.cap_mask);
1133
1134 od->dma.dev = &pdev->dev;
1135 od->dma.device_free_chan_resources = owl_dma_free_chan_resources;
1136 od->dma.device_tx_status = owl_dma_tx_status;
1137 od->dma.device_issue_pending = owl_dma_issue_pending;
1138 od->dma.device_prep_dma_memcpy = owl_dma_prep_memcpy;
1139 od->dma.device_prep_slave_sg = owl_dma_prep_slave_sg;
1140 od->dma.device_prep_dma_cyclic = owl_prep_dma_cyclic;
1141 od->dma.device_config = owl_dma_config;
1142 od->dma.device_pause = owl_dma_pause;
1143 od->dma.device_resume = owl_dma_resume;
1144 od->dma.device_terminate_all = owl_dma_terminate_all;
1145 od->dma.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
1146 od->dma.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
1147 od->dma.directions = BIT(DMA_MEM_TO_MEM);
1148 od->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1149
1150 INIT_LIST_HEAD(&od->dma.channels);
1151
1152 od->clk = devm_clk_get(&pdev->dev, NULL);
1153 if (IS_ERR(od->clk)) {
1154 dev_err(&pdev->dev, "unable to get clock\n");
1155 return PTR_ERR(od->clk);
1156 }
1157
1158 /*
1159 * Eventhough the DMA controller is capable of generating 4
1160 * IRQ's for DMA priority feature, we only use 1 IRQ for
1161 * simplification.
1162 */
1163 od->irq = platform_get_irq(pdev, 0);
1164 ret = devm_request_irq(&pdev->dev, od->irq, owl_dma_interrupt, 0,
1165 dev_name(&pdev->dev), od);
1166 if (ret) {
1167 dev_err(&pdev->dev, "unable to request IRQ\n");
1168 return ret;
1169 }
1170
1171 /* Init physical channel */
1172 od->pchans = devm_kcalloc(&pdev->dev, od->nr_pchans,
1173 sizeof(struct owl_dma_pchan), GFP_KERNEL);
1174 if (!od->pchans)
1175 return -ENOMEM;
1176
1177 for (i = 0; i < od->nr_pchans; i++) {
1178 struct owl_dma_pchan *pchan = &od->pchans[i];
1179
1180 pchan->id = i;
1181 pchan->base = od->base + OWL_DMA_CHAN_BASE(i);
1182 }
1183
1184 /* Init virtual channel */
1185 od->vchans = devm_kcalloc(&pdev->dev, od->nr_vchans,
1186 sizeof(struct owl_dma_vchan), GFP_KERNEL);
1187 if (!od->vchans)
1188 return -ENOMEM;
1189
1190 for (i = 0; i < od->nr_vchans; i++) {
1191 struct owl_dma_vchan *vchan = &od->vchans[i];
1192
1193 vchan->vc.desc_free = owl_dma_desc_free;
1194 vchan_init(&vchan->vc, &od->dma);
1195 }
1196
1197 /* Create a pool of consistent memory blocks for hardware descriptors */
1198 od->lli_pool = dma_pool_create(dev_name(od->dma.dev), od->dma.dev,
1199 sizeof(struct owl_dma_lli),
1200 __alignof__(struct owl_dma_lli),
1201 0);
1202 if (!od->lli_pool) {
1203 dev_err(&pdev->dev, "unable to allocate DMA descriptor pool\n");
1204 return -ENOMEM;
1205 }
1206
1207 clk_prepare_enable(od->clk);
1208
1209 ret = dma_async_device_register(&od->dma);
1210 if (ret) {
1211 dev_err(&pdev->dev, "failed to register DMA engine device\n");
1212 goto err_pool_free;
1213 }
1214
1215 /* Device-tree DMA controller registration */
1216 ret = of_dma_controller_register(pdev->dev.of_node,
1217 owl_dma_of_xlate, od);
1218 if (ret) {
1219 dev_err(&pdev->dev, "of_dma_controller_register failed\n");
1220 goto err_dma_unregister;
1221 }
1222
1223 return 0;
1224
1225err_dma_unregister:
1226 dma_async_device_unregister(&od->dma);
1227err_pool_free:
1228 clk_disable_unprepare(od->clk);
1229 dma_pool_destroy(od->lli_pool);
1230
1231 return ret;
1232}
1233
1234static void owl_dma_remove(struct platform_device *pdev)
1235{
1236 struct owl_dma *od = platform_get_drvdata(pdev);
1237
1238 of_dma_controller_free(pdev->dev.of_node);
1239 dma_async_device_unregister(&od->dma);
1240
1241 /* Mask all interrupts for this execution environment */
1242 dma_writel(od, OWL_DMA_IRQ_EN0, 0x0);
1243
1244 /* Make sure we won't have any further interrupts */
1245 devm_free_irq(od->dma.dev, od->irq, od);
1246
1247 owl_dma_free(od);
1248
1249 clk_disable_unprepare(od->clk);
1250 dma_pool_destroy(od->lli_pool);
1251}
1252
1253static struct platform_driver owl_dma_driver = {
1254 .probe = owl_dma_probe,
1255 .remove_new = owl_dma_remove,
1256 .driver = {
1257 .name = "dma-owl",
1258 .of_match_table = of_match_ptr(owl_dma_match),
1259 },
1260};
1261
1262static int owl_dma_init(void)
1263{
1264 return platform_driver_register(&owl_dma_driver);
1265}
1266subsys_initcall(owl_dma_init);
1267
1268static void __exit owl_dma_exit(void)
1269{
1270 platform_driver_unregister(&owl_dma_driver);
1271}
1272module_exit(owl_dma_exit);
1273
1274MODULE_AUTHOR("David Liu <liuwei@actions-semi.com>");
1275MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
1276MODULE_DESCRIPTION("Actions Semi Owl SoCs DMA driver");
1277MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0+
2//
3// Actions Semi Owl SoCs DMA driver
4//
5// Copyright (c) 2014 Actions Semi Inc.
6// Author: David Liu <liuwei@actions-semi.com>
7//
8// Copyright (c) 2018 Linaro Ltd.
9// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
10
11#include <linux/bitops.h>
12#include <linux/clk.h>
13#include <linux/delay.h>
14#include <linux/dmaengine.h>
15#include <linux/dma-mapping.h>
16#include <linux/dmapool.h>
17#include <linux/err.h>
18#include <linux/init.h>
19#include <linux/interrupt.h>
20#include <linux/io.h>
21#include <linux/mm.h>
22#include <linux/module.h>
23#include <linux/of_device.h>
24#include <linux/of_dma.h>
25#include <linux/slab.h>
26#include "virt-dma.h"
27
28#define OWL_DMA_FRAME_MAX_LENGTH 0xfffff
29
30/* Global DMA Controller Registers */
31#define OWL_DMA_IRQ_PD0 0x00
32#define OWL_DMA_IRQ_PD1 0x04
33#define OWL_DMA_IRQ_PD2 0x08
34#define OWL_DMA_IRQ_PD3 0x0C
35#define OWL_DMA_IRQ_EN0 0x10
36#define OWL_DMA_IRQ_EN1 0x14
37#define OWL_DMA_IRQ_EN2 0x18
38#define OWL_DMA_IRQ_EN3 0x1C
39#define OWL_DMA_SECURE_ACCESS_CTL 0x20
40#define OWL_DMA_NIC_QOS 0x24
41#define OWL_DMA_DBGSEL 0x28
42#define OWL_DMA_IDLE_STAT 0x2C
43
44/* Channel Registers */
45#define OWL_DMA_CHAN_BASE(i) (0x100 + (i) * 0x100)
46#define OWL_DMAX_MODE 0x00
47#define OWL_DMAX_SOURCE 0x04
48#define OWL_DMAX_DESTINATION 0x08
49#define OWL_DMAX_FRAME_LEN 0x0C
50#define OWL_DMAX_FRAME_CNT 0x10
51#define OWL_DMAX_REMAIN_FRAME_CNT 0x14
52#define OWL_DMAX_REMAIN_CNT 0x18
53#define OWL_DMAX_SOURCE_STRIDE 0x1C
54#define OWL_DMAX_DESTINATION_STRIDE 0x20
55#define OWL_DMAX_START 0x24
56#define OWL_DMAX_PAUSE 0x28
57#define OWL_DMAX_CHAINED_CTL 0x2C
58#define OWL_DMAX_CONSTANT 0x30
59#define OWL_DMAX_LINKLIST_CTL 0x34
60#define OWL_DMAX_NEXT_DESCRIPTOR 0x38
61#define OWL_DMAX_CURRENT_DESCRIPTOR_NUM 0x3C
62#define OWL_DMAX_INT_CTL 0x40
63#define OWL_DMAX_INT_STATUS 0x44
64#define OWL_DMAX_CURRENT_SOURCE_POINTER 0x48
65#define OWL_DMAX_CURRENT_DESTINATION_POINTER 0x4C
66
67/* OWL_DMAX_MODE Bits */
68#define OWL_DMA_MODE_TS(x) (((x) & GENMASK(5, 0)) << 0)
69#define OWL_DMA_MODE_ST(x) (((x) & GENMASK(1, 0)) << 8)
70#define OWL_DMA_MODE_ST_DEV OWL_DMA_MODE_ST(0)
71#define OWL_DMA_MODE_ST_DCU OWL_DMA_MODE_ST(2)
72#define OWL_DMA_MODE_ST_SRAM OWL_DMA_MODE_ST(3)
73#define OWL_DMA_MODE_DT(x) (((x) & GENMASK(1, 0)) << 10)
74#define OWL_DMA_MODE_DT_DEV OWL_DMA_MODE_DT(0)
75#define OWL_DMA_MODE_DT_DCU OWL_DMA_MODE_DT(2)
76#define OWL_DMA_MODE_DT_SRAM OWL_DMA_MODE_DT(3)
77#define OWL_DMA_MODE_SAM(x) (((x) & GENMASK(1, 0)) << 16)
78#define OWL_DMA_MODE_SAM_CONST OWL_DMA_MODE_SAM(0)
79#define OWL_DMA_MODE_SAM_INC OWL_DMA_MODE_SAM(1)
80#define OWL_DMA_MODE_SAM_STRIDE OWL_DMA_MODE_SAM(2)
81#define OWL_DMA_MODE_DAM(x) (((x) & GENMASK(1, 0)) << 18)
82#define OWL_DMA_MODE_DAM_CONST OWL_DMA_MODE_DAM(0)
83#define OWL_DMA_MODE_DAM_INC OWL_DMA_MODE_DAM(1)
84#define OWL_DMA_MODE_DAM_STRIDE OWL_DMA_MODE_DAM(2)
85#define OWL_DMA_MODE_PW(x) (((x) & GENMASK(2, 0)) << 20)
86#define OWL_DMA_MODE_CB BIT(23)
87#define OWL_DMA_MODE_NDDBW(x) (((x) & 0x1) << 28)
88#define OWL_DMA_MODE_NDDBW_32BIT OWL_DMA_MODE_NDDBW(0)
89#define OWL_DMA_MODE_NDDBW_8BIT OWL_DMA_MODE_NDDBW(1)
90#define OWL_DMA_MODE_CFE BIT(29)
91#define OWL_DMA_MODE_LME BIT(30)
92#define OWL_DMA_MODE_CME BIT(31)
93
94/* OWL_DMAX_LINKLIST_CTL Bits */
95#define OWL_DMA_LLC_SAV(x) (((x) & GENMASK(1, 0)) << 8)
96#define OWL_DMA_LLC_SAV_INC OWL_DMA_LLC_SAV(0)
97#define OWL_DMA_LLC_SAV_LOAD_NEXT OWL_DMA_LLC_SAV(1)
98#define OWL_DMA_LLC_SAV_LOAD_PREV OWL_DMA_LLC_SAV(2)
99#define OWL_DMA_LLC_DAV(x) (((x) & GENMASK(1, 0)) << 10)
100#define OWL_DMA_LLC_DAV_INC OWL_DMA_LLC_DAV(0)
101#define OWL_DMA_LLC_DAV_LOAD_NEXT OWL_DMA_LLC_DAV(1)
102#define OWL_DMA_LLC_DAV_LOAD_PREV OWL_DMA_LLC_DAV(2)
103#define OWL_DMA_LLC_SUSPEND BIT(16)
104
105/* OWL_DMAX_INT_CTL Bits */
106#define OWL_DMA_INTCTL_BLOCK BIT(0)
107#define OWL_DMA_INTCTL_SUPER_BLOCK BIT(1)
108#define OWL_DMA_INTCTL_FRAME BIT(2)
109#define OWL_DMA_INTCTL_HALF_FRAME BIT(3)
110#define OWL_DMA_INTCTL_LAST_FRAME BIT(4)
111
112/* OWL_DMAX_INT_STATUS Bits */
113#define OWL_DMA_INTSTAT_BLOCK BIT(0)
114#define OWL_DMA_INTSTAT_SUPER_BLOCK BIT(1)
115#define OWL_DMA_INTSTAT_FRAME BIT(2)
116#define OWL_DMA_INTSTAT_HALF_FRAME BIT(3)
117#define OWL_DMA_INTSTAT_LAST_FRAME BIT(4)
118
119/* Pack shift and newshift in a single word */
120#define BIT_FIELD(val, width, shift, newshift) \
121 ((((val) >> (shift)) & ((BIT(width)) - 1)) << (newshift))
122
123/**
124 * struct owl_dma_lli_hw - Hardware link list for dma transfer
125 * @next_lli: physical address of the next link list
126 * @saddr: source physical address
127 * @daddr: destination physical address
128 * @flen: frame length
129 * @fcnt: frame count
130 * @src_stride: source stride
131 * @dst_stride: destination stride
132 * @ctrla: dma_mode and linklist ctrl config
133 * @ctrlb: interrupt config
134 * @const_num: data for constant fill
135 */
136struct owl_dma_lli_hw {
137 u32 next_lli;
138 u32 saddr;
139 u32 daddr;
140 u32 flen:20;
141 u32 fcnt:12;
142 u32 src_stride;
143 u32 dst_stride;
144 u32 ctrla;
145 u32 ctrlb;
146 u32 const_num;
147};
148
149/**
150 * struct owl_dma_lli - Link list for dma transfer
151 * @hw: hardware link list
152 * @phys: physical address of hardware link list
153 * @node: node for txd's lli_list
154 */
155struct owl_dma_lli {
156 struct owl_dma_lli_hw hw;
157 dma_addr_t phys;
158 struct list_head node;
159};
160
161/**
162 * struct owl_dma_txd - Wrapper for struct dma_async_tx_descriptor
163 * @vd: virtual DMA descriptor
164 * @lli_list: link list of lli nodes
165 * @cyclic: flag to indicate cyclic transfers
166 */
167struct owl_dma_txd {
168 struct virt_dma_desc vd;
169 struct list_head lli_list;
170 bool cyclic;
171};
172
173/**
174 * struct owl_dma_pchan - Holder for the physical channels
175 * @id: physical index to this channel
176 * @base: virtual memory base for the dma channel
177 * @vchan: the virtual channel currently being served by this physical channel
178 * @lock: a lock to use when altering an instance of this struct
179 */
180struct owl_dma_pchan {
181 u32 id;
182 void __iomem *base;
183 struct owl_dma_vchan *vchan;
184 spinlock_t lock;
185};
186
187/**
188 * struct owl_dma_pchan - Wrapper for DMA ENGINE channel
189 * @vc: wrappped virtual channel
190 * @pchan: the physical channel utilized by this channel
191 * @txd: active transaction on this channel
192 * @cfg: slave configuration for this channel
193 * @drq: physical DMA request ID for this channel
194 */
195struct owl_dma_vchan {
196 struct virt_dma_chan vc;
197 struct owl_dma_pchan *pchan;
198 struct owl_dma_txd *txd;
199 struct dma_slave_config cfg;
200 u8 drq;
201};
202
203/**
204 * struct owl_dma - Holder for the Owl DMA controller
205 * @dma: dma engine for this instance
206 * @base: virtual memory base for the DMA controller
207 * @clk: clock for the DMA controller
208 * @lock: a lock to use when change DMA controller global register
209 * @lli_pool: a pool for the LLI descriptors
210 * @irq: interrupt ID for the DMA controller
211 * @nr_pchans: the number of physical channels
212 * @pchans: array of data for the physical channels
213 * @nr_vchans: the number of physical channels
214 * @vchans: array of data for the physical channels
215 */
216struct owl_dma {
217 struct dma_device dma;
218 void __iomem *base;
219 struct clk *clk;
220 spinlock_t lock;
221 struct dma_pool *lli_pool;
222 int irq;
223
224 unsigned int nr_pchans;
225 struct owl_dma_pchan *pchans;
226
227 unsigned int nr_vchans;
228 struct owl_dma_vchan *vchans;
229};
230
231static void pchan_update(struct owl_dma_pchan *pchan, u32 reg,
232 u32 val, bool state)
233{
234 u32 regval;
235
236 regval = readl(pchan->base + reg);
237
238 if (state)
239 regval |= val;
240 else
241 regval &= ~val;
242
243 writel(val, pchan->base + reg);
244}
245
246static void pchan_writel(struct owl_dma_pchan *pchan, u32 reg, u32 data)
247{
248 writel(data, pchan->base + reg);
249}
250
251static u32 pchan_readl(struct owl_dma_pchan *pchan, u32 reg)
252{
253 return readl(pchan->base + reg);
254}
255
256static void dma_update(struct owl_dma *od, u32 reg, u32 val, bool state)
257{
258 u32 regval;
259
260 regval = readl(od->base + reg);
261
262 if (state)
263 regval |= val;
264 else
265 regval &= ~val;
266
267 writel(val, od->base + reg);
268}
269
270static void dma_writel(struct owl_dma *od, u32 reg, u32 data)
271{
272 writel(data, od->base + reg);
273}
274
275static u32 dma_readl(struct owl_dma *od, u32 reg)
276{
277 return readl(od->base + reg);
278}
279
280static inline struct owl_dma *to_owl_dma(struct dma_device *dd)
281{
282 return container_of(dd, struct owl_dma, dma);
283}
284
285static struct device *chan2dev(struct dma_chan *chan)
286{
287 return &chan->dev->device;
288}
289
290static inline struct owl_dma_vchan *to_owl_vchan(struct dma_chan *chan)
291{
292 return container_of(chan, struct owl_dma_vchan, vc.chan);
293}
294
295static inline struct owl_dma_txd *to_owl_txd(struct dma_async_tx_descriptor *tx)
296{
297 return container_of(tx, struct owl_dma_txd, vd.tx);
298}
299
300static inline u32 llc_hw_ctrla(u32 mode, u32 llc_ctl)
301{
302 u32 ctl;
303
304 ctl = BIT_FIELD(mode, 4, 28, 28) |
305 BIT_FIELD(mode, 8, 16, 20) |
306 BIT_FIELD(mode, 4, 8, 16) |
307 BIT_FIELD(mode, 6, 0, 10) |
308 BIT_FIELD(llc_ctl, 2, 10, 8) |
309 BIT_FIELD(llc_ctl, 2, 8, 6);
310
311 return ctl;
312}
313
314static inline u32 llc_hw_ctrlb(u32 int_ctl)
315{
316 u32 ctl;
317
318 ctl = BIT_FIELD(int_ctl, 7, 0, 18);
319
320 return ctl;
321}
322
323static void owl_dma_free_lli(struct owl_dma *od,
324 struct owl_dma_lli *lli)
325{
326 list_del(&lli->node);
327 dma_pool_free(od->lli_pool, lli, lli->phys);
328}
329
330static struct owl_dma_lli *owl_dma_alloc_lli(struct owl_dma *od)
331{
332 struct owl_dma_lli *lli;
333 dma_addr_t phys;
334
335 lli = dma_pool_alloc(od->lli_pool, GFP_NOWAIT, &phys);
336 if (!lli)
337 return NULL;
338
339 INIT_LIST_HEAD(&lli->node);
340 lli->phys = phys;
341
342 return lli;
343}
344
345static struct owl_dma_lli *owl_dma_add_lli(struct owl_dma_txd *txd,
346 struct owl_dma_lli *prev,
347 struct owl_dma_lli *next,
348 bool is_cyclic)
349{
350 if (!is_cyclic)
351 list_add_tail(&next->node, &txd->lli_list);
352
353 if (prev) {
354 prev->hw.next_lli = next->phys;
355 prev->hw.ctrla |= llc_hw_ctrla(OWL_DMA_MODE_LME, 0);
356 }
357
358 return next;
359}
360
361static inline int owl_dma_cfg_lli(struct owl_dma_vchan *vchan,
362 struct owl_dma_lli *lli,
363 dma_addr_t src, dma_addr_t dst,
364 u32 len, enum dma_transfer_direction dir,
365 struct dma_slave_config *sconfig,
366 bool is_cyclic)
367{
368 struct owl_dma_lli_hw *hw = &lli->hw;
369 u32 mode;
370
371 mode = OWL_DMA_MODE_PW(0);
372
373 switch (dir) {
374 case DMA_MEM_TO_MEM:
375 mode |= OWL_DMA_MODE_TS(0) | OWL_DMA_MODE_ST_DCU |
376 OWL_DMA_MODE_DT_DCU | OWL_DMA_MODE_SAM_INC |
377 OWL_DMA_MODE_DAM_INC;
378
379 break;
380 case DMA_MEM_TO_DEV:
381 mode |= OWL_DMA_MODE_TS(vchan->drq)
382 | OWL_DMA_MODE_ST_DCU | OWL_DMA_MODE_DT_DEV
383 | OWL_DMA_MODE_SAM_INC | OWL_DMA_MODE_DAM_CONST;
384
385 /*
386 * Hardware only supports 32bit and 8bit buswidth. Since the
387 * default is 32bit, select 8bit only when requested.
388 */
389 if (sconfig->dst_addr_width == DMA_SLAVE_BUSWIDTH_1_BYTE)
390 mode |= OWL_DMA_MODE_NDDBW_8BIT;
391
392 break;
393 case DMA_DEV_TO_MEM:
394 mode |= OWL_DMA_MODE_TS(vchan->drq)
395 | OWL_DMA_MODE_ST_DEV | OWL_DMA_MODE_DT_DCU
396 | OWL_DMA_MODE_SAM_CONST | OWL_DMA_MODE_DAM_INC;
397
398 /*
399 * Hardware only supports 32bit and 8bit buswidth. Since the
400 * default is 32bit, select 8bit only when requested.
401 */
402 if (sconfig->src_addr_width == DMA_SLAVE_BUSWIDTH_1_BYTE)
403 mode |= OWL_DMA_MODE_NDDBW_8BIT;
404
405 break;
406 default:
407 return -EINVAL;
408 }
409
410 hw->next_lli = 0; /* One link list by default */
411 hw->saddr = src;
412 hw->daddr = dst;
413
414 hw->fcnt = 1; /* Frame count fixed as 1 */
415 hw->flen = len; /* Max frame length is 1MB */
416 hw->src_stride = 0;
417 hw->dst_stride = 0;
418 hw->ctrla = llc_hw_ctrla(mode,
419 OWL_DMA_LLC_SAV_LOAD_NEXT |
420 OWL_DMA_LLC_DAV_LOAD_NEXT);
421
422 if (is_cyclic)
423 hw->ctrlb = llc_hw_ctrlb(OWL_DMA_INTCTL_BLOCK);
424 else
425 hw->ctrlb = llc_hw_ctrlb(OWL_DMA_INTCTL_SUPER_BLOCK);
426
427 return 0;
428}
429
430static struct owl_dma_pchan *owl_dma_get_pchan(struct owl_dma *od,
431 struct owl_dma_vchan *vchan)
432{
433 struct owl_dma_pchan *pchan = NULL;
434 unsigned long flags;
435 int i;
436
437 for (i = 0; i < od->nr_pchans; i++) {
438 pchan = &od->pchans[i];
439
440 spin_lock_irqsave(&pchan->lock, flags);
441 if (!pchan->vchan) {
442 pchan->vchan = vchan;
443 spin_unlock_irqrestore(&pchan->lock, flags);
444 break;
445 }
446
447 spin_unlock_irqrestore(&pchan->lock, flags);
448 }
449
450 return pchan;
451}
452
453static int owl_dma_pchan_busy(struct owl_dma *od, struct owl_dma_pchan *pchan)
454{
455 unsigned int val;
456
457 val = dma_readl(od, OWL_DMA_IDLE_STAT);
458
459 return !(val & (1 << pchan->id));
460}
461
462static void owl_dma_terminate_pchan(struct owl_dma *od,
463 struct owl_dma_pchan *pchan)
464{
465 unsigned long flags;
466 u32 irq_pd;
467
468 pchan_writel(pchan, OWL_DMAX_START, 0);
469 pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
470
471 spin_lock_irqsave(&od->lock, flags);
472 dma_update(od, OWL_DMA_IRQ_EN0, (1 << pchan->id), false);
473
474 irq_pd = dma_readl(od, OWL_DMA_IRQ_PD0);
475 if (irq_pd & (1 << pchan->id)) {
476 dev_warn(od->dma.dev,
477 "terminating pchan %d that still has pending irq\n",
478 pchan->id);
479 dma_writel(od, OWL_DMA_IRQ_PD0, (1 << pchan->id));
480 }
481
482 pchan->vchan = NULL;
483
484 spin_unlock_irqrestore(&od->lock, flags);
485}
486
487static void owl_dma_pause_pchan(struct owl_dma_pchan *pchan)
488{
489 pchan_writel(pchan, 1, OWL_DMAX_PAUSE);
490}
491
492static void owl_dma_resume_pchan(struct owl_dma_pchan *pchan)
493{
494 pchan_writel(pchan, 0, OWL_DMAX_PAUSE);
495}
496
497static int owl_dma_start_next_txd(struct owl_dma_vchan *vchan)
498{
499 struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
500 struct virt_dma_desc *vd = vchan_next_desc(&vchan->vc);
501 struct owl_dma_pchan *pchan = vchan->pchan;
502 struct owl_dma_txd *txd = to_owl_txd(&vd->tx);
503 struct owl_dma_lli *lli;
504 unsigned long flags;
505 u32 int_ctl;
506
507 list_del(&vd->node);
508
509 vchan->txd = txd;
510
511 /* Wait for channel inactive */
512 while (owl_dma_pchan_busy(od, pchan))
513 cpu_relax();
514
515 lli = list_first_entry(&txd->lli_list,
516 struct owl_dma_lli, node);
517
518 if (txd->cyclic)
519 int_ctl = OWL_DMA_INTCTL_BLOCK;
520 else
521 int_ctl = OWL_DMA_INTCTL_SUPER_BLOCK;
522
523 pchan_writel(pchan, OWL_DMAX_MODE, OWL_DMA_MODE_LME);
524 pchan_writel(pchan, OWL_DMAX_LINKLIST_CTL,
525 OWL_DMA_LLC_SAV_LOAD_NEXT | OWL_DMA_LLC_DAV_LOAD_NEXT);
526 pchan_writel(pchan, OWL_DMAX_NEXT_DESCRIPTOR, lli->phys);
527 pchan_writel(pchan, OWL_DMAX_INT_CTL, int_ctl);
528
529 /* Clear IRQ status for this pchan */
530 pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
531
532 spin_lock_irqsave(&od->lock, flags);
533
534 dma_update(od, OWL_DMA_IRQ_EN0, (1 << pchan->id), true);
535
536 spin_unlock_irqrestore(&od->lock, flags);
537
538 dev_dbg(chan2dev(&vchan->vc.chan), "starting pchan %d\n", pchan->id);
539
540 /* Start DMA transfer for this pchan */
541 pchan_writel(pchan, OWL_DMAX_START, 0x1);
542
543 return 0;
544}
545
546static void owl_dma_phy_free(struct owl_dma *od, struct owl_dma_vchan *vchan)
547{
548 /* Ensure that the physical channel is stopped */
549 owl_dma_terminate_pchan(od, vchan->pchan);
550
551 vchan->pchan = NULL;
552}
553
554static irqreturn_t owl_dma_interrupt(int irq, void *dev_id)
555{
556 struct owl_dma *od = dev_id;
557 struct owl_dma_vchan *vchan;
558 struct owl_dma_pchan *pchan;
559 unsigned long pending;
560 int i;
561 unsigned int global_irq_pending, chan_irq_pending;
562
563 spin_lock(&od->lock);
564
565 pending = dma_readl(od, OWL_DMA_IRQ_PD0);
566
567 /* Clear IRQ status for each pchan */
568 for_each_set_bit(i, &pending, od->nr_pchans) {
569 pchan = &od->pchans[i];
570 pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
571 }
572
573 /* Clear pending IRQ */
574 dma_writel(od, OWL_DMA_IRQ_PD0, pending);
575
576 /* Check missed pending IRQ */
577 for (i = 0; i < od->nr_pchans; i++) {
578 pchan = &od->pchans[i];
579 chan_irq_pending = pchan_readl(pchan, OWL_DMAX_INT_CTL) &
580 pchan_readl(pchan, OWL_DMAX_INT_STATUS);
581
582 /* Dummy read to ensure OWL_DMA_IRQ_PD0 value is updated */
583 dma_readl(od, OWL_DMA_IRQ_PD0);
584
585 global_irq_pending = dma_readl(od, OWL_DMA_IRQ_PD0);
586
587 if (chan_irq_pending && !(global_irq_pending & BIT(i))) {
588 dev_dbg(od->dma.dev,
589 "global and channel IRQ pending match err\n");
590
591 /* Clear IRQ status for this pchan */
592 pchan_update(pchan, OWL_DMAX_INT_STATUS,
593 0xff, false);
594
595 /* Update global IRQ pending */
596 pending |= BIT(i);
597 }
598 }
599
600 spin_unlock(&od->lock);
601
602 for_each_set_bit(i, &pending, od->nr_pchans) {
603 struct owl_dma_txd *txd;
604
605 pchan = &od->pchans[i];
606
607 vchan = pchan->vchan;
608 if (!vchan) {
609 dev_warn(od->dma.dev, "no vchan attached on pchan %d\n",
610 pchan->id);
611 continue;
612 }
613
614 spin_lock(&vchan->vc.lock);
615
616 txd = vchan->txd;
617 if (txd) {
618 vchan->txd = NULL;
619
620 vchan_cookie_complete(&txd->vd);
621
622 /*
623 * Start the next descriptor (if any),
624 * otherwise free this channel.
625 */
626 if (vchan_next_desc(&vchan->vc))
627 owl_dma_start_next_txd(vchan);
628 else
629 owl_dma_phy_free(od, vchan);
630 }
631
632 spin_unlock(&vchan->vc.lock);
633 }
634
635 return IRQ_HANDLED;
636}
637
638static void owl_dma_free_txd(struct owl_dma *od, struct owl_dma_txd *txd)
639{
640 struct owl_dma_lli *lli, *_lli;
641
642 if (unlikely(!txd))
643 return;
644
645 list_for_each_entry_safe(lli, _lli, &txd->lli_list, node)
646 owl_dma_free_lli(od, lli);
647
648 kfree(txd);
649}
650
651static void owl_dma_desc_free(struct virt_dma_desc *vd)
652{
653 struct owl_dma *od = to_owl_dma(vd->tx.chan->device);
654 struct owl_dma_txd *txd = to_owl_txd(&vd->tx);
655
656 owl_dma_free_txd(od, txd);
657}
658
659static int owl_dma_terminate_all(struct dma_chan *chan)
660{
661 struct owl_dma *od = to_owl_dma(chan->device);
662 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
663 unsigned long flags;
664 LIST_HEAD(head);
665
666 spin_lock_irqsave(&vchan->vc.lock, flags);
667
668 if (vchan->pchan)
669 owl_dma_phy_free(od, vchan);
670
671 if (vchan->txd) {
672 owl_dma_desc_free(&vchan->txd->vd);
673 vchan->txd = NULL;
674 }
675
676 vchan_get_all_descriptors(&vchan->vc, &head);
677 vchan_dma_desc_free_list(&vchan->vc, &head);
678
679 spin_unlock_irqrestore(&vchan->vc.lock, flags);
680
681 return 0;
682}
683
684static int owl_dma_config(struct dma_chan *chan,
685 struct dma_slave_config *config)
686{
687 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
688
689 /* Reject definitely invalid configurations */
690 if (config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
691 config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
692 return -EINVAL;
693
694 memcpy(&vchan->cfg, config, sizeof(struct dma_slave_config));
695
696 return 0;
697}
698
699static int owl_dma_pause(struct dma_chan *chan)
700{
701 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
702 unsigned long flags;
703
704 spin_lock_irqsave(&vchan->vc.lock, flags);
705
706 owl_dma_pause_pchan(vchan->pchan);
707
708 spin_unlock_irqrestore(&vchan->vc.lock, flags);
709
710 return 0;
711}
712
713static int owl_dma_resume(struct dma_chan *chan)
714{
715 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
716 unsigned long flags;
717
718 if (!vchan->pchan && !vchan->txd)
719 return 0;
720
721 dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc);
722
723 spin_lock_irqsave(&vchan->vc.lock, flags);
724
725 owl_dma_resume_pchan(vchan->pchan);
726
727 spin_unlock_irqrestore(&vchan->vc.lock, flags);
728
729 return 0;
730}
731
732static u32 owl_dma_getbytes_chan(struct owl_dma_vchan *vchan)
733{
734 struct owl_dma_pchan *pchan;
735 struct owl_dma_txd *txd;
736 struct owl_dma_lli *lli;
737 unsigned int next_lli_phy;
738 size_t bytes;
739
740 pchan = vchan->pchan;
741 txd = vchan->txd;
742
743 if (!pchan || !txd)
744 return 0;
745
746 /* Get remain count of current node in link list */
747 bytes = pchan_readl(pchan, OWL_DMAX_REMAIN_CNT);
748
749 /* Loop through the preceding nodes to get total remaining bytes */
750 if (pchan_readl(pchan, OWL_DMAX_MODE) & OWL_DMA_MODE_LME) {
751 next_lli_phy = pchan_readl(pchan, OWL_DMAX_NEXT_DESCRIPTOR);
752 list_for_each_entry(lli, &txd->lli_list, node) {
753 /* Start from the next active node */
754 if (lli->phys == next_lli_phy) {
755 list_for_each_entry(lli, &txd->lli_list, node)
756 bytes += lli->hw.flen;
757 break;
758 }
759 }
760 }
761
762 return bytes;
763}
764
765static enum dma_status owl_dma_tx_status(struct dma_chan *chan,
766 dma_cookie_t cookie,
767 struct dma_tx_state *state)
768{
769 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
770 struct owl_dma_lli *lli;
771 struct virt_dma_desc *vd;
772 struct owl_dma_txd *txd;
773 enum dma_status ret;
774 unsigned long flags;
775 size_t bytes = 0;
776
777 ret = dma_cookie_status(chan, cookie, state);
778 if (ret == DMA_COMPLETE || !state)
779 return ret;
780
781 spin_lock_irqsave(&vchan->vc.lock, flags);
782
783 vd = vchan_find_desc(&vchan->vc, cookie);
784 if (vd) {
785 txd = to_owl_txd(&vd->tx);
786 list_for_each_entry(lli, &txd->lli_list, node)
787 bytes += lli->hw.flen;
788 } else {
789 bytes = owl_dma_getbytes_chan(vchan);
790 }
791
792 spin_unlock_irqrestore(&vchan->vc.lock, flags);
793
794 dma_set_residue(state, bytes);
795
796 return ret;
797}
798
799static void owl_dma_phy_alloc_and_start(struct owl_dma_vchan *vchan)
800{
801 struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
802 struct owl_dma_pchan *pchan;
803
804 pchan = owl_dma_get_pchan(od, vchan);
805 if (!pchan)
806 return;
807
808 dev_dbg(od->dma.dev, "allocated pchan %d\n", pchan->id);
809
810 vchan->pchan = pchan;
811 owl_dma_start_next_txd(vchan);
812}
813
814static void owl_dma_issue_pending(struct dma_chan *chan)
815{
816 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
817 unsigned long flags;
818
819 spin_lock_irqsave(&vchan->vc.lock, flags);
820 if (vchan_issue_pending(&vchan->vc)) {
821 if (!vchan->pchan)
822 owl_dma_phy_alloc_and_start(vchan);
823 }
824 spin_unlock_irqrestore(&vchan->vc.lock, flags);
825}
826
827static struct dma_async_tx_descriptor
828 *owl_dma_prep_memcpy(struct dma_chan *chan,
829 dma_addr_t dst, dma_addr_t src,
830 size_t len, unsigned long flags)
831{
832 struct owl_dma *od = to_owl_dma(chan->device);
833 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
834 struct owl_dma_txd *txd;
835 struct owl_dma_lli *lli, *prev = NULL;
836 size_t offset, bytes;
837 int ret;
838
839 if (!len)
840 return NULL;
841
842 txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
843 if (!txd)
844 return NULL;
845
846 INIT_LIST_HEAD(&txd->lli_list);
847
848 /* Process the transfer as frame by frame */
849 for (offset = 0; offset < len; offset += bytes) {
850 lli = owl_dma_alloc_lli(od);
851 if (!lli) {
852 dev_warn(chan2dev(chan), "failed to allocate lli\n");
853 goto err_txd_free;
854 }
855
856 bytes = min_t(size_t, (len - offset), OWL_DMA_FRAME_MAX_LENGTH);
857
858 ret = owl_dma_cfg_lli(vchan, lli, src + offset, dst + offset,
859 bytes, DMA_MEM_TO_MEM,
860 &vchan->cfg, txd->cyclic);
861 if (ret) {
862 dev_warn(chan2dev(chan), "failed to config lli\n");
863 goto err_txd_free;
864 }
865
866 prev = owl_dma_add_lli(txd, prev, lli, false);
867 }
868
869 return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
870
871err_txd_free:
872 owl_dma_free_txd(od, txd);
873 return NULL;
874}
875
876static struct dma_async_tx_descriptor
877 *owl_dma_prep_slave_sg(struct dma_chan *chan,
878 struct scatterlist *sgl,
879 unsigned int sg_len,
880 enum dma_transfer_direction dir,
881 unsigned long flags, void *context)
882{
883 struct owl_dma *od = to_owl_dma(chan->device);
884 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
885 struct dma_slave_config *sconfig = &vchan->cfg;
886 struct owl_dma_txd *txd;
887 struct owl_dma_lli *lli, *prev = NULL;
888 struct scatterlist *sg;
889 dma_addr_t addr, src = 0, dst = 0;
890 size_t len;
891 int ret, i;
892
893 txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
894 if (!txd)
895 return NULL;
896
897 INIT_LIST_HEAD(&txd->lli_list);
898
899 for_each_sg(sgl, sg, sg_len, i) {
900 addr = sg_dma_address(sg);
901 len = sg_dma_len(sg);
902
903 if (len > OWL_DMA_FRAME_MAX_LENGTH) {
904 dev_err(od->dma.dev,
905 "frame length exceeds max supported length");
906 goto err_txd_free;
907 }
908
909 lli = owl_dma_alloc_lli(od);
910 if (!lli) {
911 dev_err(chan2dev(chan), "failed to allocate lli");
912 goto err_txd_free;
913 }
914
915 if (dir == DMA_MEM_TO_DEV) {
916 src = addr;
917 dst = sconfig->dst_addr;
918 } else {
919 src = sconfig->src_addr;
920 dst = addr;
921 }
922
923 ret = owl_dma_cfg_lli(vchan, lli, src, dst, len, dir, sconfig,
924 txd->cyclic);
925 if (ret) {
926 dev_warn(chan2dev(chan), "failed to config lli");
927 goto err_txd_free;
928 }
929
930 prev = owl_dma_add_lli(txd, prev, lli, false);
931 }
932
933 return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
934
935err_txd_free:
936 owl_dma_free_txd(od, txd);
937
938 return NULL;
939}
940
941static struct dma_async_tx_descriptor
942 *owl_prep_dma_cyclic(struct dma_chan *chan,
943 dma_addr_t buf_addr, size_t buf_len,
944 size_t period_len,
945 enum dma_transfer_direction dir,
946 unsigned long flags)
947{
948 struct owl_dma *od = to_owl_dma(chan->device);
949 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
950 struct dma_slave_config *sconfig = &vchan->cfg;
951 struct owl_dma_txd *txd;
952 struct owl_dma_lli *lli, *prev = NULL, *first = NULL;
953 dma_addr_t src = 0, dst = 0;
954 unsigned int periods = buf_len / period_len;
955 int ret, i;
956
957 txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
958 if (!txd)
959 return NULL;
960
961 INIT_LIST_HEAD(&txd->lli_list);
962 txd->cyclic = true;
963
964 for (i = 0; i < periods; i++) {
965 lli = owl_dma_alloc_lli(od);
966 if (!lli) {
967 dev_warn(chan2dev(chan), "failed to allocate lli");
968 goto err_txd_free;
969 }
970
971 if (dir == DMA_MEM_TO_DEV) {
972 src = buf_addr + (period_len * i);
973 dst = sconfig->dst_addr;
974 } else if (dir == DMA_DEV_TO_MEM) {
975 src = sconfig->src_addr;
976 dst = buf_addr + (period_len * i);
977 }
978
979 ret = owl_dma_cfg_lli(vchan, lli, src, dst, period_len,
980 dir, sconfig, txd->cyclic);
981 if (ret) {
982 dev_warn(chan2dev(chan), "failed to config lli");
983 goto err_txd_free;
984 }
985
986 if (!first)
987 first = lli;
988
989 prev = owl_dma_add_lli(txd, prev, lli, false);
990 }
991
992 /* close the cyclic list */
993 owl_dma_add_lli(txd, prev, first, true);
994
995 return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
996
997err_txd_free:
998 owl_dma_free_txd(od, txd);
999
1000 return NULL;
1001}
1002
1003static void owl_dma_free_chan_resources(struct dma_chan *chan)
1004{
1005 struct owl_dma_vchan *vchan = to_owl_vchan(chan);
1006
1007 /* Ensure all queued descriptors are freed */
1008 vchan_free_chan_resources(&vchan->vc);
1009}
1010
1011static inline void owl_dma_free(struct owl_dma *od)
1012{
1013 struct owl_dma_vchan *vchan = NULL;
1014 struct owl_dma_vchan *next;
1015
1016 list_for_each_entry_safe(vchan,
1017 next, &od->dma.channels, vc.chan.device_node) {
1018 list_del(&vchan->vc.chan.device_node);
1019 tasklet_kill(&vchan->vc.task);
1020 }
1021}
1022
1023static struct dma_chan *owl_dma_of_xlate(struct of_phandle_args *dma_spec,
1024 struct of_dma *ofdma)
1025{
1026 struct owl_dma *od = ofdma->of_dma_data;
1027 struct owl_dma_vchan *vchan;
1028 struct dma_chan *chan;
1029 u8 drq = dma_spec->args[0];
1030
1031 if (drq > od->nr_vchans)
1032 return NULL;
1033
1034 chan = dma_get_any_slave_channel(&od->dma);
1035 if (!chan)
1036 return NULL;
1037
1038 vchan = to_owl_vchan(chan);
1039 vchan->drq = drq;
1040
1041 return chan;
1042}
1043
1044static int owl_dma_probe(struct platform_device *pdev)
1045{
1046 struct device_node *np = pdev->dev.of_node;
1047 struct owl_dma *od;
1048 struct resource *res;
1049 int ret, i, nr_channels, nr_requests;
1050
1051 od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
1052 if (!od)
1053 return -ENOMEM;
1054
1055 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1056 if (!res)
1057 return -EINVAL;
1058
1059 od->base = devm_ioremap_resource(&pdev->dev, res);
1060 if (IS_ERR(od->base))
1061 return PTR_ERR(od->base);
1062
1063 ret = of_property_read_u32(np, "dma-channels", &nr_channels);
1064 if (ret) {
1065 dev_err(&pdev->dev, "can't get dma-channels\n");
1066 return ret;
1067 }
1068
1069 ret = of_property_read_u32(np, "dma-requests", &nr_requests);
1070 if (ret) {
1071 dev_err(&pdev->dev, "can't get dma-requests\n");
1072 return ret;
1073 }
1074
1075 dev_info(&pdev->dev, "dma-channels %d, dma-requests %d\n",
1076 nr_channels, nr_requests);
1077
1078 od->nr_pchans = nr_channels;
1079 od->nr_vchans = nr_requests;
1080
1081 pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
1082
1083 platform_set_drvdata(pdev, od);
1084 spin_lock_init(&od->lock);
1085
1086 dma_cap_set(DMA_MEMCPY, od->dma.cap_mask);
1087 dma_cap_set(DMA_SLAVE, od->dma.cap_mask);
1088 dma_cap_set(DMA_CYCLIC, od->dma.cap_mask);
1089
1090 od->dma.dev = &pdev->dev;
1091 od->dma.device_free_chan_resources = owl_dma_free_chan_resources;
1092 od->dma.device_tx_status = owl_dma_tx_status;
1093 od->dma.device_issue_pending = owl_dma_issue_pending;
1094 od->dma.device_prep_dma_memcpy = owl_dma_prep_memcpy;
1095 od->dma.device_prep_slave_sg = owl_dma_prep_slave_sg;
1096 od->dma.device_prep_dma_cyclic = owl_prep_dma_cyclic;
1097 od->dma.device_config = owl_dma_config;
1098 od->dma.device_pause = owl_dma_pause;
1099 od->dma.device_resume = owl_dma_resume;
1100 od->dma.device_terminate_all = owl_dma_terminate_all;
1101 od->dma.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
1102 od->dma.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
1103 od->dma.directions = BIT(DMA_MEM_TO_MEM);
1104 od->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
1105
1106 INIT_LIST_HEAD(&od->dma.channels);
1107
1108 od->clk = devm_clk_get(&pdev->dev, NULL);
1109 if (IS_ERR(od->clk)) {
1110 dev_err(&pdev->dev, "unable to get clock\n");
1111 return PTR_ERR(od->clk);
1112 }
1113
1114 /*
1115 * Eventhough the DMA controller is capable of generating 4
1116 * IRQ's for DMA priority feature, we only use 1 IRQ for
1117 * simplification.
1118 */
1119 od->irq = platform_get_irq(pdev, 0);
1120 ret = devm_request_irq(&pdev->dev, od->irq, owl_dma_interrupt, 0,
1121 dev_name(&pdev->dev), od);
1122 if (ret) {
1123 dev_err(&pdev->dev, "unable to request IRQ\n");
1124 return ret;
1125 }
1126
1127 /* Init physical channel */
1128 od->pchans = devm_kcalloc(&pdev->dev, od->nr_pchans,
1129 sizeof(struct owl_dma_pchan), GFP_KERNEL);
1130 if (!od->pchans)
1131 return -ENOMEM;
1132
1133 for (i = 0; i < od->nr_pchans; i++) {
1134 struct owl_dma_pchan *pchan = &od->pchans[i];
1135
1136 pchan->id = i;
1137 pchan->base = od->base + OWL_DMA_CHAN_BASE(i);
1138 }
1139
1140 /* Init virtual channel */
1141 od->vchans = devm_kcalloc(&pdev->dev, od->nr_vchans,
1142 sizeof(struct owl_dma_vchan), GFP_KERNEL);
1143 if (!od->vchans)
1144 return -ENOMEM;
1145
1146 for (i = 0; i < od->nr_vchans; i++) {
1147 struct owl_dma_vchan *vchan = &od->vchans[i];
1148
1149 vchan->vc.desc_free = owl_dma_desc_free;
1150 vchan_init(&vchan->vc, &od->dma);
1151 }
1152
1153 /* Create a pool of consistent memory blocks for hardware descriptors */
1154 od->lli_pool = dma_pool_create(dev_name(od->dma.dev), od->dma.dev,
1155 sizeof(struct owl_dma_lli),
1156 __alignof__(struct owl_dma_lli),
1157 0);
1158 if (!od->lli_pool) {
1159 dev_err(&pdev->dev, "unable to allocate DMA descriptor pool\n");
1160 return -ENOMEM;
1161 }
1162
1163 clk_prepare_enable(od->clk);
1164
1165 ret = dma_async_device_register(&od->dma);
1166 if (ret) {
1167 dev_err(&pdev->dev, "failed to register DMA engine device\n");
1168 goto err_pool_free;
1169 }
1170
1171 /* Device-tree DMA controller registration */
1172 ret = of_dma_controller_register(pdev->dev.of_node,
1173 owl_dma_of_xlate, od);
1174 if (ret) {
1175 dev_err(&pdev->dev, "of_dma_controller_register failed\n");
1176 goto err_dma_unregister;
1177 }
1178
1179 return 0;
1180
1181err_dma_unregister:
1182 dma_async_device_unregister(&od->dma);
1183err_pool_free:
1184 clk_disable_unprepare(od->clk);
1185 dma_pool_destroy(od->lli_pool);
1186
1187 return ret;
1188}
1189
1190static int owl_dma_remove(struct platform_device *pdev)
1191{
1192 struct owl_dma *od = platform_get_drvdata(pdev);
1193
1194 of_dma_controller_free(pdev->dev.of_node);
1195 dma_async_device_unregister(&od->dma);
1196
1197 /* Mask all interrupts for this execution environment */
1198 dma_writel(od, OWL_DMA_IRQ_EN0, 0x0);
1199
1200 /* Make sure we won't have any further interrupts */
1201 devm_free_irq(od->dma.dev, od->irq, od);
1202
1203 owl_dma_free(od);
1204
1205 clk_disable_unprepare(od->clk);
1206
1207 return 0;
1208}
1209
1210static const struct of_device_id owl_dma_match[] = {
1211 { .compatible = "actions,s900-dma", },
1212 { /* sentinel */ }
1213};
1214MODULE_DEVICE_TABLE(of, owl_dma_match);
1215
1216static struct platform_driver owl_dma_driver = {
1217 .probe = owl_dma_probe,
1218 .remove = owl_dma_remove,
1219 .driver = {
1220 .name = "dma-owl",
1221 .of_match_table = of_match_ptr(owl_dma_match),
1222 },
1223};
1224
1225static int owl_dma_init(void)
1226{
1227 return platform_driver_register(&owl_dma_driver);
1228}
1229subsys_initcall(owl_dma_init);
1230
1231static void __exit owl_dma_exit(void)
1232{
1233 platform_driver_unregister(&owl_dma_driver);
1234}
1235module_exit(owl_dma_exit);
1236
1237MODULE_AUTHOR("David Liu <liuwei@actions-semi.com>");
1238MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
1239MODULE_DESCRIPTION("Actions Semi Owl SoCs DMA driver");
1240MODULE_LICENSE("GPL");