1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2018 Álvaro Fernández Rojas <noltari@gmail.com>
4  *
5  * Derived from linux/drivers/dma/bcm63xx-iudma.c:
6  *	Copyright (C) 2015 Simon Arlott <simon@fire.lp0.eu>
7  *
8  * Derived from linux/drivers/net/ethernet/broadcom/bcm63xx_enet.c:
9  *	Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
10  *
11  * Derived from bcm963xx_4.12L.06B_consumer/shared/opensource/include/bcm963xx/63268_map_part.h:
12  *	Copyright (C) 2000-2010 Broadcom Corporation
13  *
14  * Derived from bcm963xx_4.12L.06B_consumer/bcmdrivers/opensource/net/enet/impl4/bcmenet.c:
15  *	Copyright (C) 2010 Broadcom Corporation
16  */
17 
18 #include <common.h>
19 #include <clk.h>
20 #include <cpu_func.h>
21 #include <dm.h>
22 #include <dma-uclass.h>
23 #include <log.h>
24 #include <malloc.h>
25 #include <memalign.h>
26 #include <net.h>
27 #include <reset.h>
28 #include <asm/io.h>
29 #include <linux/bitops.h>
30 #include <linux/delay.h>
31 
32 #define DMA_RX_DESC	6
33 #define DMA_TX_DESC	1
34 
35 /* DMA Channels */
36 #define DMA_CHAN_FLOWC(x)		((x) >> 1)
37 #define DMA_CHAN_MAX			16
38 #define DMA_CHAN_SIZE			0x10
39 #define DMA_CHAN_TOUT			500
40 
41 /* DMA Global Configuration register */
42 #define DMA_CFG_REG			0x00
43 #define  DMA_CFG_ENABLE_SHIFT		0
44 #define  DMA_CFG_ENABLE_MASK		(1 << DMA_CFG_ENABLE_SHIFT)
45 #define  DMA_CFG_FLOWC_ENABLE(x)	BIT(DMA_CHAN_FLOWC(x) + 1)
46 #define  DMA_CFG_NCHANS_SHIFT		24
47 #define  DMA_CFG_NCHANS_MASK		(0xf << DMA_CFG_NCHANS_SHIFT)
48 
49 /* DMA Global Flow Control registers */
50 #define DMA_FLOWC_THR_LO_REG(x)		(0x04 + DMA_CHAN_FLOWC(x) * 0x0c)
51 #define DMA_FLOWC_THR_HI_REG(x)		(0x08 + DMA_CHAN_FLOWC(x) * 0x0c)
52 #define DMA_FLOWC_ALLOC_REG(x)		(0x0c + DMA_CHAN_FLOWC(x) * 0x0c)
53 #define  DMA_FLOWC_ALLOC_FORCE_SHIFT	31
54 #define  DMA_FLOWC_ALLOC_FORCE_MASK	(1 << DMA_FLOWC_ALLOC_FORCE_SHIFT)
55 
56 /* DMA Global Reset register */
57 #define DMA_RST_REG			0x34
58 #define  DMA_RST_CHAN_SHIFT		0
59 #define  DMA_RST_CHAN_MASK(x)		(1 << x)
60 
61 /* DMA Channel Configuration register */
62 #define DMAC_CFG_REG(x)			(DMA_CHAN_SIZE * (x) + 0x00)
63 #define  DMAC_CFG_ENABLE_SHIFT		0
64 #define  DMAC_CFG_ENABLE_MASK		(1 << DMAC_CFG_ENABLE_SHIFT)
65 #define  DMAC_CFG_PKT_HALT_SHIFT	1
66 #define  DMAC_CFG_PKT_HALT_MASK		(1 << DMAC_CFG_PKT_HALT_SHIFT)
67 #define  DMAC_CFG_BRST_HALT_SHIFT	2
68 #define  DMAC_CFG_BRST_HALT_MASK	(1 << DMAC_CFG_BRST_HALT_SHIFT)
69 
70 /* DMA Channel Max Burst Length register */
71 #define DMAC_BURST_REG(x)		(DMA_CHAN_SIZE * (x) + 0x0c)
72 
73 /* DMA SRAM Descriptor Ring Start register */
74 #define DMAS_RSTART_REG(x)		(DMA_CHAN_SIZE * (x) + 0x00)
75 
76 /* DMA SRAM State/Bytes done/ring offset register */
77 #define DMAS_STATE_DATA_REG(x)		(DMA_CHAN_SIZE * (x) + 0x04)
78 
79 /* DMA SRAM Buffer Descriptor status and length register */
80 #define DMAS_DESC_LEN_STATUS_REG(x)	(DMA_CHAN_SIZE * (x) + 0x08)
81 
82 /* DMA SRAM Buffer Descriptor status and length register */
83 #define DMAS_DESC_BASE_BUFPTR_REG(x)	(DMA_CHAN_SIZE * (x) + 0x0c)
84 
85 /* DMA Descriptor Status */
86 #define DMAD_ST_CRC_SHIFT		8
87 #define DMAD_ST_CRC_MASK		(1 << DMAD_ST_CRC_SHIFT)
88 #define DMAD_ST_WRAP_SHIFT		12
89 #define DMAD_ST_WRAP_MASK		(1 << DMAD_ST_WRAP_SHIFT)
90 #define DMAD_ST_SOP_SHIFT		13
91 #define DMAD_ST_SOP_MASK		(1 << DMAD_ST_SOP_SHIFT)
92 #define DMAD_ST_EOP_SHIFT		14
93 #define DMAD_ST_EOP_MASK		(1 << DMAD_ST_EOP_SHIFT)
94 #define DMAD_ST_OWN_SHIFT		15
95 #define DMAD_ST_OWN_MASK		(1 << DMAD_ST_OWN_SHIFT)
96 
97 #define DMAD6348_ST_OV_ERR_SHIFT	0
98 #define DMAD6348_ST_OV_ERR_MASK		(1 << DMAD6348_ST_OV_ERR_SHIFT)
99 #define DMAD6348_ST_CRC_ERR_SHIFT	1
100 #define DMAD6348_ST_CRC_ERR_MASK	(1 << DMAD6348_ST_CRC_ERR_SHIFT)
101 #define DMAD6348_ST_RX_ERR_SHIFT	2
102 #define DMAD6348_ST_RX_ERR_MASK		(1 << DMAD6348_ST_RX_ERR_SHIFT)
103 #define DMAD6348_ST_OS_ERR_SHIFT	4
104 #define DMAD6348_ST_OS_ERR_MASK		(1 << DMAD6348_ST_OS_ERR_SHIFT)
105 #define DMAD6348_ST_UN_ERR_SHIFT	9
106 #define DMAD6348_ST_UN_ERR_MASK		(1 << DMAD6348_ST_UN_ERR_SHIFT)
107 
108 struct bcm6348_dma_desc {
109 	uint16_t length;
110 	uint16_t status;
111 	uint32_t address;
112 };
113 
114 struct bcm6348_chan_priv {
115 	void __iomem *dma_ring;
116 	uint8_t dma_ring_size;
117 	uint8_t desc_id;
118 	uint8_t desc_cnt;
119 	bool *busy_desc;
120 	bool running;
121 };
122 
123 struct bcm6348_iudma_hw {
124 	uint16_t err_mask;
125 };
126 
127 struct bcm6348_iudma_priv {
128 	const struct bcm6348_iudma_hw *hw;
129 	void __iomem *base;
130 	void __iomem *chan;
131 	void __iomem *sram;
132 	struct bcm6348_chan_priv **ch_priv;
133 	uint8_t n_channels;
134 };
135 
bcm6348_iudma_chan_is_rx(uint8_t ch)136 static inline bool bcm6348_iudma_chan_is_rx(uint8_t ch)
137 {
138 	return !(ch & 1);
139 }
140 
bcm6348_iudma_fdc(void * ptr,ulong size)141 static inline void bcm6348_iudma_fdc(void *ptr, ulong size)
142 {
143 	ulong start = (ulong) ptr;
144 
145 	flush_dcache_range(start, start + size);
146 }
147 
bcm6348_iudma_idc(void * ptr,ulong size)148 static inline void bcm6348_iudma_idc(void *ptr, ulong size)
149 {
150 	ulong start = (ulong) ptr;
151 
152 	invalidate_dcache_range(start, start + size);
153 }
154 
bcm6348_iudma_chan_stop(struct bcm6348_iudma_priv * priv,uint8_t ch)155 static void bcm6348_iudma_chan_stop(struct bcm6348_iudma_priv *priv,
156 				    uint8_t ch)
157 {
158 	unsigned int timeout = DMA_CHAN_TOUT;
159 
160 	do {
161 		uint32_t cfg, halt;
162 
163 		if (timeout > DMA_CHAN_TOUT / 2)
164 			halt = DMAC_CFG_PKT_HALT_MASK;
165 		else
166 			halt = DMAC_CFG_BRST_HALT_MASK;
167 
168 		/* try to stop dma channel */
169 		writel_be(halt, priv->chan + DMAC_CFG_REG(ch));
170 		mb();
171 
172 		/* check if channel was stopped */
173 		cfg = readl_be(priv->chan + DMAC_CFG_REG(ch));
174 		if (!(cfg & DMAC_CFG_ENABLE_MASK))
175 			break;
176 
177 		udelay(1);
178 	} while (--timeout);
179 
180 	if (!timeout)
181 		pr_err("unable to stop channel %u\n", ch);
182 
183 	/* reset dma channel */
184 	setbits_be32(priv->base + DMA_RST_REG, DMA_RST_CHAN_MASK(ch));
185 	mb();
186 	clrbits_be32(priv->base + DMA_RST_REG, DMA_RST_CHAN_MASK(ch));
187 }
188 
bcm6348_iudma_disable(struct dma * dma)189 static int bcm6348_iudma_disable(struct dma *dma)
190 {
191 	struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
192 	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
193 
194 	/* stop dma channel */
195 	bcm6348_iudma_chan_stop(priv, dma->id);
196 
197 	/* dma flow control */
198 	if (bcm6348_iudma_chan_is_rx(dma->id))
199 		writel_be(DMA_FLOWC_ALLOC_FORCE_MASK,
200 			  DMA_FLOWC_ALLOC_REG(dma->id));
201 
202 	/* init channel config */
203 	ch_priv->running = false;
204 	ch_priv->desc_id = 0;
205 	if (bcm6348_iudma_chan_is_rx(dma->id))
206 		ch_priv->desc_cnt = 0;
207 	else
208 		ch_priv->desc_cnt = ch_priv->dma_ring_size;
209 
210 	return 0;
211 }
212 
bcm6348_iudma_enable(struct dma * dma)213 static int bcm6348_iudma_enable(struct dma *dma)
214 {
215 	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
216 	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
217 	struct bcm6348_dma_desc *dma_desc = ch_priv->dma_ring;
218 	uint8_t i;
219 
220 	/* dma ring init */
221 	for (i = 0; i < ch_priv->desc_cnt; i++) {
222 		if (bcm6348_iudma_chan_is_rx(dma->id)) {
223 			ch_priv->busy_desc[i] = false;
224 			dma_desc->status |= DMAD_ST_OWN_MASK;
225 		} else {
226 			dma_desc->status = 0;
227 			dma_desc->length = 0;
228 			dma_desc->address = 0;
229 		}
230 
231 		if (i == ch_priv->desc_cnt - 1)
232 			dma_desc->status |= DMAD_ST_WRAP_MASK;
233 
234 		dma_desc++;
235 	}
236 
237 	/* init to first descriptor */
238 	ch_priv->desc_id = 0;
239 
240 	/* force cache writeback */
241 	bcm6348_iudma_fdc(ch_priv->dma_ring,
242 			  sizeof(*dma_desc) * ch_priv->desc_cnt);
243 
244 	/* clear sram */
245 	writel_be(0, priv->sram + DMAS_STATE_DATA_REG(dma->id));
246 	writel_be(0, priv->sram + DMAS_DESC_LEN_STATUS_REG(dma->id));
247 	writel_be(0, priv->sram + DMAS_DESC_BASE_BUFPTR_REG(dma->id));
248 
249 	/* set dma ring start */
250 	writel_be(virt_to_phys(ch_priv->dma_ring),
251 		  priv->sram + DMAS_RSTART_REG(dma->id));
252 
253 	/* set flow control */
254 	if (bcm6348_iudma_chan_is_rx(dma->id)) {
255 		u32 val;
256 
257 		setbits_be32(priv->base + DMA_CFG_REG,
258 			     DMA_CFG_FLOWC_ENABLE(dma->id));
259 
260 		val = ch_priv->desc_cnt / 3;
261 		writel_be(val, priv->base + DMA_FLOWC_THR_LO_REG(dma->id));
262 
263 		val = (ch_priv->desc_cnt * 2) / 3;
264 		writel_be(val, priv->base + DMA_FLOWC_THR_HI_REG(dma->id));
265 
266 		writel_be(0, priv->base + DMA_FLOWC_ALLOC_REG(dma->id));
267 	}
268 
269 	/* set dma max burst */
270 	writel_be(ch_priv->desc_cnt,
271 		  priv->chan + DMAC_BURST_REG(dma->id));
272 
273 	/* kick rx dma channel */
274 	if (bcm6348_iudma_chan_is_rx(dma->id))
275 		setbits_be32(priv->chan + DMAC_CFG_REG(dma->id),
276 			     DMAC_CFG_ENABLE_MASK);
277 
278 	/* channel is now enabled */
279 	ch_priv->running = true;
280 
281 	return 0;
282 }
283 
bcm6348_iudma_request(struct dma * dma)284 static int bcm6348_iudma_request(struct dma *dma)
285 {
286 	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
287 	struct bcm6348_chan_priv *ch_priv;
288 
289 	/* check if channel is valid */
290 	if (dma->id >= priv->n_channels)
291 		return -ENODEV;
292 
293 	/* alloc channel private data */
294 	priv->ch_priv[dma->id] = calloc(1, sizeof(struct bcm6348_chan_priv));
295 	if (!priv->ch_priv[dma->id])
296 		return -ENOMEM;
297 	ch_priv = priv->ch_priv[dma->id];
298 
299 	/* alloc dma ring */
300 	if (bcm6348_iudma_chan_is_rx(dma->id))
301 		ch_priv->dma_ring_size = DMA_RX_DESC;
302 	else
303 		ch_priv->dma_ring_size = DMA_TX_DESC;
304 
305 	ch_priv->dma_ring =
306 		malloc_cache_aligned(sizeof(struct bcm6348_dma_desc) *
307 				     ch_priv->dma_ring_size);
308 	if (!ch_priv->dma_ring)
309 		return -ENOMEM;
310 
311 	/* init channel config */
312 	ch_priv->running = false;
313 	ch_priv->desc_id = 0;
314 	if (bcm6348_iudma_chan_is_rx(dma->id)) {
315 		ch_priv->desc_cnt = 0;
316 		ch_priv->busy_desc = NULL;
317 	} else {
318 		ch_priv->desc_cnt = ch_priv->dma_ring_size;
319 		ch_priv->busy_desc = calloc(ch_priv->desc_cnt, sizeof(bool));
320 	}
321 
322 	return 0;
323 }
324 
bcm6348_iudma_receive(struct dma * dma,void ** dst,void * metadata)325 static int bcm6348_iudma_receive(struct dma *dma, void **dst, void *metadata)
326 {
327 	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
328 	const struct bcm6348_iudma_hw *hw = priv->hw;
329 	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
330 	struct bcm6348_dma_desc *dma_desc = dma_desc = ch_priv->dma_ring;
331 	int ret;
332 
333 	if (!ch_priv->running)
334 		return -EINVAL;
335 
336 	/* get dma ring descriptor address */
337 	dma_desc += ch_priv->desc_id;
338 
339 	/* invalidate cache data */
340 	bcm6348_iudma_idc(dma_desc, sizeof(*dma_desc));
341 
342 	/* check dma own */
343 	if (dma_desc->status & DMAD_ST_OWN_MASK)
344 		return -EAGAIN;
345 
346 	/* check pkt */
347 	if (!(dma_desc->status & DMAD_ST_EOP_MASK) ||
348 	    !(dma_desc->status & DMAD_ST_SOP_MASK) ||
349 	    (dma_desc->status & hw->err_mask)) {
350 		pr_err("invalid pkt received (ch=%ld desc=%u) (st=%04x)\n",
351 		       dma->id, ch_priv->desc_id, dma_desc->status);
352 		ret = -EAGAIN;
353 	} else {
354 		/* set dma buffer address */
355 		*dst = phys_to_virt(dma_desc->address);
356 
357 		/* invalidate cache data */
358 		bcm6348_iudma_idc(*dst, dma_desc->length);
359 
360 		/* return packet length */
361 		ret = dma_desc->length;
362 	}
363 
364 	/* busy dma descriptor */
365 	ch_priv->busy_desc[ch_priv->desc_id] = true;
366 
367 	/* increment dma descriptor */
368 	ch_priv->desc_id = (ch_priv->desc_id + 1) % ch_priv->desc_cnt;
369 
370 	return ret;
371 }
372 
bcm6348_iudma_send(struct dma * dma,void * src,size_t len,void * metadata)373 static int bcm6348_iudma_send(struct dma *dma, void *src, size_t len,
374 			      void *metadata)
375 {
376 	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
377 	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
378 	struct bcm6348_dma_desc *dma_desc;
379 	uint16_t status;
380 
381 	if (!ch_priv->running)
382                 return -EINVAL;
383 
384 	/* flush cache */
385 	bcm6348_iudma_fdc(src, len);
386 
387 	/* get dma ring descriptor address */
388 	dma_desc = ch_priv->dma_ring;
389 	dma_desc += ch_priv->desc_id;
390 
391 	/* config dma descriptor */
392 	status = (DMAD_ST_OWN_MASK |
393 		  DMAD_ST_EOP_MASK |
394 		  DMAD_ST_CRC_MASK |
395 		  DMAD_ST_SOP_MASK);
396 	if (ch_priv->desc_id == ch_priv->desc_cnt - 1)
397 		status |= DMAD_ST_WRAP_MASK;
398 
399 	/* set dma descriptor */
400 	dma_desc->address = virt_to_phys(src);
401 	dma_desc->length = len;
402 	dma_desc->status = status;
403 
404 	/* flush cache */
405 	bcm6348_iudma_fdc(dma_desc, sizeof(*dma_desc));
406 
407 	/* kick tx dma channel */
408 	setbits_be32(priv->chan + DMAC_CFG_REG(dma->id), DMAC_CFG_ENABLE_MASK);
409 
410 	/* poll dma status */
411 	do {
412 		/* invalidate cache */
413 		bcm6348_iudma_idc(dma_desc, sizeof(*dma_desc));
414 
415 		if (!(dma_desc->status & DMAD_ST_OWN_MASK))
416 			break;
417 	} while(1);
418 
419 	/* increment dma descriptor */
420 	ch_priv->desc_id = (ch_priv->desc_id + 1) % ch_priv->desc_cnt;
421 
422 	return 0;
423 }
424 
bcm6348_iudma_free_rcv_buf(struct dma * dma,void * dst,size_t size)425 static int bcm6348_iudma_free_rcv_buf(struct dma *dma, void *dst, size_t size)
426 {
427 	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
428 	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
429 	struct bcm6348_dma_desc *dma_desc = ch_priv->dma_ring;
430 	uint16_t status;
431 	uint8_t i;
432 	u32 cfg;
433 
434 	/* get dirty dma descriptor */
435 	for (i = 0; i < ch_priv->desc_cnt; i++) {
436 		if (phys_to_virt(dma_desc->address) == dst)
437 			break;
438 
439 		dma_desc++;
440 	}
441 
442 	/* dma descriptor not found */
443 	if (i == ch_priv->desc_cnt) {
444 		pr_err("dirty dma descriptor not found\n");
445 		return -ENOENT;
446 	}
447 
448 	/* invalidate cache */
449 	bcm6348_iudma_idc(ch_priv->dma_ring,
450 			  sizeof(*dma_desc) * ch_priv->desc_cnt);
451 
452 	/* free dma descriptor */
453 	ch_priv->busy_desc[i] = false;
454 
455 	status = DMAD_ST_OWN_MASK;
456 	if (i == ch_priv->desc_cnt - 1)
457 		status |= DMAD_ST_WRAP_MASK;
458 
459 	dma_desc->status |= status;
460 	dma_desc->length = PKTSIZE_ALIGN;
461 
462 	/* tell dma we allocated one buffer */
463 	writel_be(1, DMA_FLOWC_ALLOC_REG(dma->id));
464 
465 	/* flush cache */
466 	bcm6348_iudma_fdc(ch_priv->dma_ring,
467 			  sizeof(*dma_desc) * ch_priv->desc_cnt);
468 
469 	/* kick rx dma channel if disabled */
470 	cfg = readl_be(priv->chan + DMAC_CFG_REG(dma->id));
471 	if (!(cfg & DMAC_CFG_ENABLE_MASK))
472 		setbits_be32(priv->chan + DMAC_CFG_REG(dma->id),
473 			     DMAC_CFG_ENABLE_MASK);
474 
475 	return 0;
476 }
477 
bcm6348_iudma_add_rcv_buf(struct dma * dma,void * dst,size_t size)478 static int bcm6348_iudma_add_rcv_buf(struct dma *dma, void *dst, size_t size)
479 {
480 	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
481 	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
482 	struct bcm6348_dma_desc *dma_desc = ch_priv->dma_ring;
483 
484 	/* no more dma descriptors available */
485 	if (ch_priv->desc_cnt == ch_priv->dma_ring_size) {
486 		pr_err("max number of buffers reached\n");
487 		return -EINVAL;
488 	}
489 
490 	/* get next dma descriptor */
491 	dma_desc += ch_priv->desc_cnt;
492 
493 	/* init dma descriptor */
494 	dma_desc->address = virt_to_phys(dst);
495 	dma_desc->length = size;
496 	dma_desc->status = 0;
497 
498 	/* flush cache */
499 	bcm6348_iudma_fdc(dma_desc, sizeof(*dma_desc));
500 
501 	/* increment dma descriptors */
502 	ch_priv->desc_cnt++;
503 
504 	return 0;
505 }
506 
bcm6348_iudma_prepare_rcv_buf(struct dma * dma,void * dst,size_t size)507 static int bcm6348_iudma_prepare_rcv_buf(struct dma *dma, void *dst,
508 					 size_t size)
509 {
510 	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
511 	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
512 
513 	/* only add new rx buffers if channel isn't running */
514 	if (ch_priv->running)
515 		return bcm6348_iudma_free_rcv_buf(dma, dst, size);
516 	else
517 		return bcm6348_iudma_add_rcv_buf(dma, dst, size);
518 }
519 
520 static const struct dma_ops bcm6348_iudma_ops = {
521 	.disable = bcm6348_iudma_disable,
522 	.enable = bcm6348_iudma_enable,
523 	.prepare_rcv_buf = bcm6348_iudma_prepare_rcv_buf,
524 	.request = bcm6348_iudma_request,
525 	.receive = bcm6348_iudma_receive,
526 	.send = bcm6348_iudma_send,
527 };
528 
529 static const struct bcm6348_iudma_hw bcm6348_hw = {
530 	.err_mask = (DMAD6348_ST_OV_ERR_MASK |
531 		     DMAD6348_ST_CRC_ERR_MASK |
532 		     DMAD6348_ST_RX_ERR_MASK |
533 		     DMAD6348_ST_OS_ERR_MASK |
534 		     DMAD6348_ST_UN_ERR_MASK),
535 };
536 
537 static const struct bcm6348_iudma_hw bcm6368_hw = {
538 	.err_mask = 0,
539 };
540 
541 static const struct udevice_id bcm6348_iudma_ids[] = {
542 	{
543 		.compatible = "brcm,bcm6348-iudma",
544 		.data = (ulong)&bcm6348_hw,
545 	}, {
546 		.compatible = "brcm,bcm6368-iudma",
547 		.data = (ulong)&bcm6368_hw,
548 	}, { /* sentinel */ }
549 };
550 
bcm6348_iudma_probe(struct udevice * dev)551 static int bcm6348_iudma_probe(struct udevice *dev)
552 {
553 	struct dma_dev_priv *uc_priv = dev_get_uclass_priv(dev);
554 	struct bcm6348_iudma_priv *priv = dev_get_priv(dev);
555 	const struct bcm6348_iudma_hw *hw =
556 		(const struct bcm6348_iudma_hw *)dev_get_driver_data(dev);
557 	uint8_t ch;
558 	int i;
559 
560 	uc_priv->supported = (DMA_SUPPORTS_DEV_TO_MEM |
561 			      DMA_SUPPORTS_MEM_TO_DEV);
562 	priv->hw = hw;
563 
564 	/* dma global base address */
565 	priv->base = dev_remap_addr_name(dev, "dma");
566 	if (!priv->base)
567 		return -EINVAL;
568 
569 	/* dma channels base address */
570 	priv->chan = dev_remap_addr_name(dev, "dma-channels");
571 	if (!priv->chan)
572 		return -EINVAL;
573 
574 	/* dma sram base address */
575 	priv->sram = dev_remap_addr_name(dev, "dma-sram");
576 	if (!priv->sram)
577 		return -EINVAL;
578 
579 	/* get number of channels */
580 	priv->n_channels = dev_read_u32_default(dev, "dma-channels", 8);
581 	if (priv->n_channels > DMA_CHAN_MAX)
582 		return -EINVAL;
583 
584 	/* try to enable clocks */
585 	for (i = 0; ; i++) {
586 		struct clk clk;
587 		int ret;
588 
589 		ret = clk_get_by_index(dev, i, &clk);
590 		if (ret < 0)
591 			break;
592 
593 		ret = clk_enable(&clk);
594 		if (ret < 0) {
595 			pr_err("error enabling clock %d\n", i);
596 			return ret;
597 		}
598 
599 		ret = clk_free(&clk);
600 		if (ret < 0) {
601 			pr_err("error freeing clock %d\n", i);
602 			return ret;
603 		}
604 	}
605 
606 	/* try to perform resets */
607 	for (i = 0; ; i++) {
608 		struct reset_ctl reset;
609 		int ret;
610 
611 		ret = reset_get_by_index(dev, i, &reset);
612 		if (ret < 0)
613 			break;
614 
615 		ret = reset_deassert(&reset);
616 		if (ret < 0) {
617 			pr_err("error deasserting reset %d\n", i);
618 			return ret;
619 		}
620 
621 		ret = reset_free(&reset);
622 		if (ret < 0) {
623 			pr_err("error freeing reset %d\n", i);
624 			return ret;
625 		}
626 	}
627 
628 	/* disable dma controller */
629 	clrbits_be32(priv->base + DMA_CFG_REG, DMA_CFG_ENABLE_MASK);
630 
631 	/* alloc channel private data pointers */
632 	priv->ch_priv = calloc(priv->n_channels,
633 			       sizeof(struct bcm6348_chan_priv*));
634 	if (!priv->ch_priv)
635 		return -ENOMEM;
636 
637 	/* stop dma channels */
638 	for (ch = 0; ch < priv->n_channels; ch++)
639 		bcm6348_iudma_chan_stop(priv, ch);
640 
641 	/* enable dma controller */
642 	setbits_be32(priv->base + DMA_CFG_REG, DMA_CFG_ENABLE_MASK);
643 
644 	return 0;
645 }
646 
647 U_BOOT_DRIVER(bcm6348_iudma) = {
648 	.name = "bcm6348_iudma",
649 	.id = UCLASS_DMA,
650 	.of_match = bcm6348_iudma_ids,
651 	.ops = &bcm6348_iudma_ops,
652 	.priv_auto	= sizeof(struct bcm6348_iudma_priv),
653 	.probe = bcm6348_iudma_probe,
654 };
655