xref: /openbmc/linux/drivers/dma/ste_dma40_ll.c (revision 842ed298)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) ST-Ericsson SA 2007-2010
4  * Author: Per Forlin <per.forlin@stericsson.com> for ST-Ericsson
5  * Author: Jonas Aaberg <jonas.aberg@stericsson.com> for ST-Ericsson
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/platform_data/dma-ste-dma40.h>
10 
11 #include "ste_dma40_ll.h"
12 
13 static u8 d40_width_to_bits(enum dma_slave_buswidth width)
14 {
15 	if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
16 		return STEDMA40_ESIZE_8_BIT;
17 	else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
18 		return STEDMA40_ESIZE_16_BIT;
19 	else if (width == DMA_SLAVE_BUSWIDTH_8_BYTES)
20 		return STEDMA40_ESIZE_64_BIT;
21 	else
22 		return STEDMA40_ESIZE_32_BIT;
23 }
24 
25 /* Sets up proper LCSP1 and LCSP3 register for a logical channel */
26 void d40_log_cfg(struct stedma40_chan_cfg *cfg,
27 		 u32 *lcsp1, u32 *lcsp3)
28 {
29 	u32 l3 = 0; /* dst */
30 	u32 l1 = 0; /* src */
31 
32 	/* src is mem? -> increase address pos */
33 	if (cfg->dir ==  DMA_MEM_TO_DEV ||
34 	    cfg->dir ==  DMA_MEM_TO_MEM)
35 		l1 |= BIT(D40_MEM_LCSP1_SCFG_INCR_POS);
36 
37 	/* dst is mem? -> increase address pos */
38 	if (cfg->dir ==  DMA_DEV_TO_MEM ||
39 	    cfg->dir ==  DMA_MEM_TO_MEM)
40 		l3 |= BIT(D40_MEM_LCSP3_DCFG_INCR_POS);
41 
42 	/* src is hw? -> master port 1 */
43 	if (cfg->dir ==  DMA_DEV_TO_MEM ||
44 	    cfg->dir ==  DMA_DEV_TO_DEV)
45 		l1 |= BIT(D40_MEM_LCSP1_SCFG_MST_POS);
46 
47 	/* dst is hw? -> master port 1 */
48 	if (cfg->dir ==  DMA_MEM_TO_DEV ||
49 	    cfg->dir ==  DMA_DEV_TO_DEV)
50 		l3 |= BIT(D40_MEM_LCSP3_DCFG_MST_POS);
51 
52 	l3 |= BIT(D40_MEM_LCSP3_DCFG_EIM_POS);
53 	l3 |= cfg->dst_info.psize << D40_MEM_LCSP3_DCFG_PSIZE_POS;
54 	l3 |= d40_width_to_bits(cfg->dst_info.data_width)
55 		<< D40_MEM_LCSP3_DCFG_ESIZE_POS;
56 
57 	l1 |= BIT(D40_MEM_LCSP1_SCFG_EIM_POS);
58 	l1 |= cfg->src_info.psize << D40_MEM_LCSP1_SCFG_PSIZE_POS;
59 	l1 |= d40_width_to_bits(cfg->src_info.data_width)
60 		<< D40_MEM_LCSP1_SCFG_ESIZE_POS;
61 
62 	*lcsp1 = l1;
63 	*lcsp3 = l3;
64 
65 }
66 
67 void d40_phy_cfg(struct stedma40_chan_cfg *cfg, u32 *src_cfg, u32 *dst_cfg)
68 {
69 	u32 src = 0;
70 	u32 dst = 0;
71 
72 	if ((cfg->dir == DMA_DEV_TO_MEM) ||
73 	    (cfg->dir == DMA_DEV_TO_DEV)) {
74 		/* Set master port to 1 */
75 		src |= BIT(D40_SREG_CFG_MST_POS);
76 		src |= D40_TYPE_TO_EVENT(cfg->dev_type);
77 
78 		if (cfg->src_info.flow_ctrl == STEDMA40_NO_FLOW_CTRL)
79 			src |= BIT(D40_SREG_CFG_PHY_TM_POS);
80 		else
81 			src |= 3 << D40_SREG_CFG_PHY_TM_POS;
82 	}
83 	if ((cfg->dir == DMA_MEM_TO_DEV) ||
84 	    (cfg->dir == DMA_DEV_TO_DEV)) {
85 		/* Set master port to 1 */
86 		dst |= BIT(D40_SREG_CFG_MST_POS);
87 		dst |= D40_TYPE_TO_EVENT(cfg->dev_type);
88 
89 		if (cfg->dst_info.flow_ctrl == STEDMA40_NO_FLOW_CTRL)
90 			dst |= BIT(D40_SREG_CFG_PHY_TM_POS);
91 		else
92 			dst |= 3 << D40_SREG_CFG_PHY_TM_POS;
93 	}
94 	/* Interrupt on end of transfer for destination */
95 	dst |= BIT(D40_SREG_CFG_TIM_POS);
96 
97 	/* Generate interrupt on error */
98 	src |= BIT(D40_SREG_CFG_EIM_POS);
99 	dst |= BIT(D40_SREG_CFG_EIM_POS);
100 
101 	/* PSIZE */
102 	if (cfg->src_info.psize != STEDMA40_PSIZE_PHY_1) {
103 		src |= BIT(D40_SREG_CFG_PHY_PEN_POS);
104 		src |= cfg->src_info.psize << D40_SREG_CFG_PSIZE_POS;
105 	}
106 	if (cfg->dst_info.psize != STEDMA40_PSIZE_PHY_1) {
107 		dst |= BIT(D40_SREG_CFG_PHY_PEN_POS);
108 		dst |= cfg->dst_info.psize << D40_SREG_CFG_PSIZE_POS;
109 	}
110 
111 	/* Element size */
112 	src |= d40_width_to_bits(cfg->src_info.data_width)
113 		<< D40_SREG_CFG_ESIZE_POS;
114 	dst |= d40_width_to_bits(cfg->dst_info.data_width)
115 		<< D40_SREG_CFG_ESIZE_POS;
116 
117 	/* Set the priority bit to high for the physical channel */
118 	if (cfg->high_priority) {
119 		src |= BIT(D40_SREG_CFG_PRI_POS);
120 		dst |= BIT(D40_SREG_CFG_PRI_POS);
121 	}
122 
123 	if (cfg->src_info.big_endian)
124 		src |= BIT(D40_SREG_CFG_LBE_POS);
125 	if (cfg->dst_info.big_endian)
126 		dst |= BIT(D40_SREG_CFG_LBE_POS);
127 
128 	*src_cfg = src;
129 	*dst_cfg = dst;
130 }
131 
132 static int d40_phy_fill_lli(struct d40_phy_lli *lli,
133 			    dma_addr_t data,
134 			    u32 data_size,
135 			    dma_addr_t next_lli,
136 			    u32 reg_cfg,
137 			    struct stedma40_half_channel_info *info,
138 			    unsigned int flags)
139 {
140 	bool addr_inc = flags & LLI_ADDR_INC;
141 	bool term_int = flags & LLI_TERM_INT;
142 	unsigned int data_width = info->data_width;
143 	int psize = info->psize;
144 	int num_elems;
145 
146 	if (psize == STEDMA40_PSIZE_PHY_1)
147 		num_elems = 1;
148 	else
149 		num_elems = 2 << psize;
150 
151 	/* Must be aligned */
152 	if (!IS_ALIGNED(data, data_width))
153 		return -EINVAL;
154 
155 	/* Transfer size can't be smaller than (num_elms * elem_size) */
156 	if (data_size < num_elems * data_width)
157 		return -EINVAL;
158 
159 	/* The number of elements. IE now many chunks */
160 	lli->reg_elt = (data_size / data_width) << D40_SREG_ELEM_PHY_ECNT_POS;
161 
162 	/*
163 	 * Distance to next element sized entry.
164 	 * Usually the size of the element unless you want gaps.
165 	 */
166 	if (addr_inc)
167 		lli->reg_elt |= data_width << D40_SREG_ELEM_PHY_EIDX_POS;
168 
169 	/* Where the data is */
170 	lli->reg_ptr = data;
171 	lli->reg_cfg = reg_cfg;
172 
173 	/* If this scatter list entry is the last one, no next link */
174 	if (next_lli == 0)
175 		lli->reg_lnk = BIT(D40_SREG_LNK_PHY_TCP_POS);
176 	else
177 		lli->reg_lnk = next_lli;
178 
179 	/* Set/clear interrupt generation on this link item.*/
180 	if (term_int)
181 		lli->reg_cfg |= BIT(D40_SREG_CFG_TIM_POS);
182 	else
183 		lli->reg_cfg &= ~BIT(D40_SREG_CFG_TIM_POS);
184 
185 	/*
186 	 * Post link - D40_SREG_LNK_PHY_PRE_POS = 0
187 	 * Relink happens after transfer completion.
188 	 */
189 
190 	return 0;
191 }
192 
193 static int d40_seg_size(int size, int data_width1, int data_width2)
194 {
195 	u32 max_w = max(data_width1, data_width2);
196 	u32 min_w = min(data_width1, data_width2);
197 	u32 seg_max = ALIGN(STEDMA40_MAX_SEG_SIZE * min_w, max_w);
198 
199 	if (seg_max > STEDMA40_MAX_SEG_SIZE)
200 		seg_max -= max_w;
201 
202 	if (size <= seg_max)
203 		return size;
204 
205 	if (size <= 2 * seg_max)
206 		return ALIGN(size / 2, max_w);
207 
208 	return seg_max;
209 }
210 
211 static struct d40_phy_lli *
212 d40_phy_buf_to_lli(struct d40_phy_lli *lli, dma_addr_t addr, u32 size,
213 		   dma_addr_t lli_phys, dma_addr_t first_phys, u32 reg_cfg,
214 		   struct stedma40_half_channel_info *info,
215 		   struct stedma40_half_channel_info *otherinfo,
216 		   unsigned long flags)
217 {
218 	bool lastlink = flags & LLI_LAST_LINK;
219 	bool addr_inc = flags & LLI_ADDR_INC;
220 	bool term_int = flags & LLI_TERM_INT;
221 	bool cyclic = flags & LLI_CYCLIC;
222 	int err;
223 	dma_addr_t next = lli_phys;
224 	int size_rest = size;
225 	int size_seg = 0;
226 
227 	/*
228 	 * This piece may be split up based on d40_seg_size(); we only want the
229 	 * term int on the last part.
230 	 */
231 	if (term_int)
232 		flags &= ~LLI_TERM_INT;
233 
234 	do {
235 		size_seg = d40_seg_size(size_rest, info->data_width,
236 					otherinfo->data_width);
237 		size_rest -= size_seg;
238 
239 		if (size_rest == 0 && term_int)
240 			flags |= LLI_TERM_INT;
241 
242 		if (size_rest == 0 && lastlink)
243 			next = cyclic ? first_phys : 0;
244 		else
245 			next = ALIGN(next + sizeof(struct d40_phy_lli),
246 				     D40_LLI_ALIGN);
247 
248 		err = d40_phy_fill_lli(lli, addr, size_seg, next,
249 				       reg_cfg, info, flags);
250 
251 		if (err)
252 			goto err;
253 
254 		lli++;
255 		if (addr_inc)
256 			addr += size_seg;
257 	} while (size_rest);
258 
259 	return lli;
260 
261 err:
262 	return NULL;
263 }
264 
265 int d40_phy_sg_to_lli(struct scatterlist *sg,
266 		      int sg_len,
267 		      dma_addr_t target,
268 		      struct d40_phy_lli *lli_sg,
269 		      dma_addr_t lli_phys,
270 		      u32 reg_cfg,
271 		      struct stedma40_half_channel_info *info,
272 		      struct stedma40_half_channel_info *otherinfo,
273 		      unsigned long flags)
274 {
275 	int total_size = 0;
276 	int i;
277 	struct scatterlist *current_sg = sg;
278 	struct d40_phy_lli *lli = lli_sg;
279 	dma_addr_t l_phys = lli_phys;
280 
281 	if (!target)
282 		flags |= LLI_ADDR_INC;
283 
284 	for_each_sg(sg, current_sg, sg_len, i) {
285 		dma_addr_t sg_addr = sg_dma_address(current_sg);
286 		unsigned int len = sg_dma_len(current_sg);
287 		dma_addr_t dst = target ?: sg_addr;
288 
289 		total_size += sg_dma_len(current_sg);
290 
291 		if (i == sg_len - 1)
292 			flags |= LLI_TERM_INT | LLI_LAST_LINK;
293 
294 		l_phys = ALIGN(lli_phys + (lli - lli_sg) *
295 			       sizeof(struct d40_phy_lli), D40_LLI_ALIGN);
296 
297 		lli = d40_phy_buf_to_lli(lli, dst, len, l_phys, lli_phys,
298 					 reg_cfg, info, otherinfo, flags);
299 
300 		if (lli == NULL)
301 			return -EINVAL;
302 	}
303 
304 	return total_size;
305 }
306 
307 
308 /* DMA logical lli operations */
309 
310 static void d40_log_lli_link(struct d40_log_lli *lli_dst,
311 			     struct d40_log_lli *lli_src,
312 			     int next, unsigned int flags)
313 {
314 	bool interrupt = flags & LLI_TERM_INT;
315 	u32 slos = 0;
316 	u32 dlos = 0;
317 
318 	if (next != -EINVAL) {
319 		slos = next * 2;
320 		dlos = next * 2 + 1;
321 	}
322 
323 	if (interrupt) {
324 		lli_dst->lcsp13 |= D40_MEM_LCSP1_SCFG_TIM_MASK;
325 		lli_dst->lcsp13 |= D40_MEM_LCSP3_DTCP_MASK;
326 	}
327 
328 	lli_src->lcsp13 = (lli_src->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
329 		(slos << D40_MEM_LCSP1_SLOS_POS);
330 
331 	lli_dst->lcsp13 = (lli_dst->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
332 		(dlos << D40_MEM_LCSP1_SLOS_POS);
333 }
334 
335 void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
336 			   struct d40_log_lli *lli_dst,
337 			   struct d40_log_lli *lli_src,
338 			   int next, unsigned int flags)
339 {
340 	d40_log_lli_link(lli_dst, lli_src, next, flags);
341 
342 	writel_relaxed(lli_src->lcsp02, &lcpa[0].lcsp0);
343 	writel_relaxed(lli_src->lcsp13, &lcpa[0].lcsp1);
344 	writel_relaxed(lli_dst->lcsp02, &lcpa[0].lcsp2);
345 	writel_relaxed(lli_dst->lcsp13, &lcpa[0].lcsp3);
346 }
347 
348 void d40_log_lli_lcla_write(struct d40_log_lli *lcla,
349 			   struct d40_log_lli *lli_dst,
350 			   struct d40_log_lli *lli_src,
351 			   int next, unsigned int flags)
352 {
353 	d40_log_lli_link(lli_dst, lli_src, next, flags);
354 
355 	writel_relaxed(lli_src->lcsp02, &lcla[0].lcsp02);
356 	writel_relaxed(lli_src->lcsp13, &lcla[0].lcsp13);
357 	writel_relaxed(lli_dst->lcsp02, &lcla[1].lcsp02);
358 	writel_relaxed(lli_dst->lcsp13, &lcla[1].lcsp13);
359 }
360 
361 static void d40_log_fill_lli(struct d40_log_lli *lli,
362 			     dma_addr_t data, u32 data_size,
363 			     u32 reg_cfg,
364 			     u32 data_width,
365 			     unsigned int flags)
366 {
367 	bool addr_inc = flags & LLI_ADDR_INC;
368 
369 	lli->lcsp13 = reg_cfg;
370 
371 	/* The number of elements to transfer */
372 	lli->lcsp02 = ((data_size / data_width) <<
373 		       D40_MEM_LCSP0_ECNT_POS) & D40_MEM_LCSP0_ECNT_MASK;
374 
375 	BUG_ON((data_size / data_width) > STEDMA40_MAX_SEG_SIZE);
376 
377 	/* 16 LSBs address of the current element */
378 	lli->lcsp02 |= data & D40_MEM_LCSP0_SPTR_MASK;
379 	/* 16 MSBs address of the current element */
380 	lli->lcsp13 |= data & D40_MEM_LCSP1_SPTR_MASK;
381 
382 	if (addr_inc)
383 		lli->lcsp13 |= D40_MEM_LCSP1_SCFG_INCR_MASK;
384 
385 }
386 
387 static struct d40_log_lli *d40_log_buf_to_lli(struct d40_log_lli *lli_sg,
388 				       dma_addr_t addr,
389 				       int size,
390 				       u32 lcsp13, /* src or dst*/
391 				       u32 data_width1,
392 				       u32 data_width2,
393 				       unsigned int flags)
394 {
395 	bool addr_inc = flags & LLI_ADDR_INC;
396 	struct d40_log_lli *lli = lli_sg;
397 	int size_rest = size;
398 	int size_seg = 0;
399 
400 	do {
401 		size_seg = d40_seg_size(size_rest, data_width1, data_width2);
402 		size_rest -= size_seg;
403 
404 		d40_log_fill_lli(lli,
405 				 addr,
406 				 size_seg,
407 				 lcsp13, data_width1,
408 				 flags);
409 		if (addr_inc)
410 			addr += size_seg;
411 		lli++;
412 	} while (size_rest);
413 
414 	return lli;
415 }
416 
417 int d40_log_sg_to_lli(struct scatterlist *sg,
418 		      int sg_len,
419 		      dma_addr_t dev_addr,
420 		      struct d40_log_lli *lli_sg,
421 		      u32 lcsp13, /* src or dst*/
422 		      u32 data_width1, u32 data_width2)
423 {
424 	int total_size = 0;
425 	struct scatterlist *current_sg = sg;
426 	int i;
427 	struct d40_log_lli *lli = lli_sg;
428 	unsigned long flags = 0;
429 
430 	if (!dev_addr)
431 		flags |= LLI_ADDR_INC;
432 
433 	for_each_sg(sg, current_sg, sg_len, i) {
434 		dma_addr_t sg_addr = sg_dma_address(current_sg);
435 		unsigned int len = sg_dma_len(current_sg);
436 		dma_addr_t addr = dev_addr ?: sg_addr;
437 
438 		total_size += sg_dma_len(current_sg);
439 
440 		lli = d40_log_buf_to_lli(lli, addr, len,
441 					 lcsp13,
442 					 data_width1,
443 					 data_width2,
444 					 flags);
445 	}
446 
447 	return total_size;
448 }
449