xref: /openbmc/linux/drivers/dma/ste_dma40_ll.c (revision f0168042)
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/dmaengine.h>
10 
11 #include "ste_dma40.h"
12 #include "ste_dma40_ll.h"
13 
14 static u8 d40_width_to_bits(enum dma_slave_buswidth width)
15 {
16 	if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
17 		return STEDMA40_ESIZE_8_BIT;
18 	else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
19 		return STEDMA40_ESIZE_16_BIT;
20 	else if (width == DMA_SLAVE_BUSWIDTH_8_BYTES)
21 		return STEDMA40_ESIZE_64_BIT;
22 	else
23 		return STEDMA40_ESIZE_32_BIT;
24 }
25 
26 /* Sets up proper LCSP1 and LCSP3 register for a logical channel */
27 void d40_log_cfg(struct stedma40_chan_cfg *cfg,
28 		 u32 *lcsp1, u32 *lcsp3)
29 {
30 	u32 l3 = 0; /* dst */
31 	u32 l1 = 0; /* src */
32 
33 	/* src is mem? -> increase address pos */
34 	if (cfg->dir ==  DMA_MEM_TO_DEV ||
35 	    cfg->dir ==  DMA_MEM_TO_MEM)
36 		l1 |= BIT(D40_MEM_LCSP1_SCFG_INCR_POS);
37 
38 	/* dst is mem? -> increase address pos */
39 	if (cfg->dir ==  DMA_DEV_TO_MEM ||
40 	    cfg->dir ==  DMA_MEM_TO_MEM)
41 		l3 |= BIT(D40_MEM_LCSP3_DCFG_INCR_POS);
42 
43 	/* src is hw? -> master port 1 */
44 	if (cfg->dir ==  DMA_DEV_TO_MEM ||
45 	    cfg->dir ==  DMA_DEV_TO_DEV)
46 		l1 |= BIT(D40_MEM_LCSP1_SCFG_MST_POS);
47 
48 	/* dst is hw? -> master port 1 */
49 	if (cfg->dir ==  DMA_MEM_TO_DEV ||
50 	    cfg->dir ==  DMA_DEV_TO_DEV)
51 		l3 |= BIT(D40_MEM_LCSP3_DCFG_MST_POS);
52 
53 	l3 |= BIT(D40_MEM_LCSP3_DCFG_EIM_POS);
54 	l3 |= cfg->dst_info.psize << D40_MEM_LCSP3_DCFG_PSIZE_POS;
55 	l3 |= d40_width_to_bits(cfg->dst_info.data_width)
56 		<< D40_MEM_LCSP3_DCFG_ESIZE_POS;
57 
58 	l1 |= BIT(D40_MEM_LCSP1_SCFG_EIM_POS);
59 	l1 |= cfg->src_info.psize << D40_MEM_LCSP1_SCFG_PSIZE_POS;
60 	l1 |= d40_width_to_bits(cfg->src_info.data_width)
61 		<< D40_MEM_LCSP1_SCFG_ESIZE_POS;
62 
63 	*lcsp1 = l1;
64 	*lcsp3 = l3;
65 
66 }
67 
68 void d40_phy_cfg(struct stedma40_chan_cfg *cfg, u32 *src_cfg, u32 *dst_cfg)
69 {
70 	u32 src = 0;
71 	u32 dst = 0;
72 
73 	if ((cfg->dir == DMA_DEV_TO_MEM) ||
74 	    (cfg->dir == DMA_DEV_TO_DEV)) {
75 		/* Set master port to 1 */
76 		src |= BIT(D40_SREG_CFG_MST_POS);
77 		src |= D40_TYPE_TO_EVENT(cfg->dev_type);
78 
79 		if (cfg->src_info.flow_ctrl == STEDMA40_NO_FLOW_CTRL)
80 			src |= BIT(D40_SREG_CFG_PHY_TM_POS);
81 		else
82 			src |= 3 << D40_SREG_CFG_PHY_TM_POS;
83 	}
84 	if ((cfg->dir == DMA_MEM_TO_DEV) ||
85 	    (cfg->dir == DMA_DEV_TO_DEV)) {
86 		/* Set master port to 1 */
87 		dst |= BIT(D40_SREG_CFG_MST_POS);
88 		dst |= D40_TYPE_TO_EVENT(cfg->dev_type);
89 
90 		if (cfg->dst_info.flow_ctrl == STEDMA40_NO_FLOW_CTRL)
91 			dst |= BIT(D40_SREG_CFG_PHY_TM_POS);
92 		else
93 			dst |= 3 << D40_SREG_CFG_PHY_TM_POS;
94 	}
95 	/* Interrupt on end of transfer for destination */
96 	dst |= BIT(D40_SREG_CFG_TIM_POS);
97 
98 	/* Generate interrupt on error */
99 	src |= BIT(D40_SREG_CFG_EIM_POS);
100 	dst |= BIT(D40_SREG_CFG_EIM_POS);
101 
102 	/* PSIZE */
103 	if (cfg->src_info.psize != STEDMA40_PSIZE_PHY_1) {
104 		src |= BIT(D40_SREG_CFG_PHY_PEN_POS);
105 		src |= cfg->src_info.psize << D40_SREG_CFG_PSIZE_POS;
106 	}
107 	if (cfg->dst_info.psize != STEDMA40_PSIZE_PHY_1) {
108 		dst |= BIT(D40_SREG_CFG_PHY_PEN_POS);
109 		dst |= cfg->dst_info.psize << D40_SREG_CFG_PSIZE_POS;
110 	}
111 
112 	/* Element size */
113 	src |= d40_width_to_bits(cfg->src_info.data_width)
114 		<< D40_SREG_CFG_ESIZE_POS;
115 	dst |= d40_width_to_bits(cfg->dst_info.data_width)
116 		<< D40_SREG_CFG_ESIZE_POS;
117 
118 	/* Set the priority bit to high for the physical channel */
119 	if (cfg->high_priority) {
120 		src |= BIT(D40_SREG_CFG_PRI_POS);
121 		dst |= BIT(D40_SREG_CFG_PRI_POS);
122 	}
123 
124 	if (cfg->src_info.big_endian)
125 		src |= BIT(D40_SREG_CFG_LBE_POS);
126 	if (cfg->dst_info.big_endian)
127 		dst |= BIT(D40_SREG_CFG_LBE_POS);
128 
129 	*src_cfg = src;
130 	*dst_cfg = dst;
131 }
132 
133 static int d40_phy_fill_lli(struct d40_phy_lli *lli,
134 			    dma_addr_t data,
135 			    u32 data_size,
136 			    dma_addr_t next_lli,
137 			    u32 reg_cfg,
138 			    struct stedma40_half_channel_info *info,
139 			    unsigned int flags)
140 {
141 	bool addr_inc = flags & LLI_ADDR_INC;
142 	bool term_int = flags & LLI_TERM_INT;
143 	unsigned int data_width = info->data_width;
144 	int psize = info->psize;
145 	int num_elems;
146 
147 	if (psize == STEDMA40_PSIZE_PHY_1)
148 		num_elems = 1;
149 	else
150 		num_elems = 2 << psize;
151 
152 	/* Must be aligned */
153 	if (!IS_ALIGNED(data, data_width))
154 		return -EINVAL;
155 
156 	/* Transfer size can't be smaller than (num_elms * elem_size) */
157 	if (data_size < num_elems * data_width)
158 		return -EINVAL;
159 
160 	/* The number of elements. IE now many chunks */
161 	lli->reg_elt = (data_size / data_width) << D40_SREG_ELEM_PHY_ECNT_POS;
162 
163 	/*
164 	 * Distance to next element sized entry.
165 	 * Usually the size of the element unless you want gaps.
166 	 */
167 	if (addr_inc)
168 		lli->reg_elt |= data_width << D40_SREG_ELEM_PHY_EIDX_POS;
169 
170 	/* Where the data is */
171 	lli->reg_ptr = data;
172 	lli->reg_cfg = reg_cfg;
173 
174 	/* If this scatter list entry is the last one, no next link */
175 	if (next_lli == 0)
176 		lli->reg_lnk = BIT(D40_SREG_LNK_PHY_TCP_POS);
177 	else
178 		lli->reg_lnk = next_lli;
179 
180 	/* Set/clear interrupt generation on this link item.*/
181 	if (term_int)
182 		lli->reg_cfg |= BIT(D40_SREG_CFG_TIM_POS);
183 	else
184 		lli->reg_cfg &= ~BIT(D40_SREG_CFG_TIM_POS);
185 
186 	/*
187 	 * Post link - D40_SREG_LNK_PHY_PRE_POS = 0
188 	 * Relink happens after transfer completion.
189 	 */
190 
191 	return 0;
192 }
193 
194 static int d40_seg_size(int size, int data_width1, int data_width2)
195 {
196 	u32 max_w = max(data_width1, data_width2);
197 	u32 min_w = min(data_width1, data_width2);
198 	u32 seg_max = ALIGN(STEDMA40_MAX_SEG_SIZE * min_w, max_w);
199 
200 	if (seg_max > STEDMA40_MAX_SEG_SIZE)
201 		seg_max -= max_w;
202 
203 	if (size <= seg_max)
204 		return size;
205 
206 	if (size <= 2 * seg_max)
207 		return ALIGN(size / 2, max_w);
208 
209 	return seg_max;
210 }
211 
212 static struct d40_phy_lli *
213 d40_phy_buf_to_lli(struct d40_phy_lli *lli, dma_addr_t addr, u32 size,
214 		   dma_addr_t lli_phys, dma_addr_t first_phys, u32 reg_cfg,
215 		   struct stedma40_half_channel_info *info,
216 		   struct stedma40_half_channel_info *otherinfo,
217 		   unsigned long flags)
218 {
219 	bool lastlink = flags & LLI_LAST_LINK;
220 	bool addr_inc = flags & LLI_ADDR_INC;
221 	bool term_int = flags & LLI_TERM_INT;
222 	bool cyclic = flags & LLI_CYCLIC;
223 	int err;
224 	dma_addr_t next = lli_phys;
225 	int size_rest = size;
226 	int size_seg = 0;
227 
228 	/*
229 	 * This piece may be split up based on d40_seg_size(); we only want the
230 	 * term int on the last part.
231 	 */
232 	if (term_int)
233 		flags &= ~LLI_TERM_INT;
234 
235 	do {
236 		size_seg = d40_seg_size(size_rest, info->data_width,
237 					otherinfo->data_width);
238 		size_rest -= size_seg;
239 
240 		if (size_rest == 0 && term_int)
241 			flags |= LLI_TERM_INT;
242 
243 		if (size_rest == 0 && lastlink)
244 			next = cyclic ? first_phys : 0;
245 		else
246 			next = ALIGN(next + sizeof(struct d40_phy_lli),
247 				     D40_LLI_ALIGN);
248 
249 		err = d40_phy_fill_lli(lli, addr, size_seg, next,
250 				       reg_cfg, info, flags);
251 
252 		if (err)
253 			goto err;
254 
255 		lli++;
256 		if (addr_inc)
257 			addr += size_seg;
258 	} while (size_rest);
259 
260 	return lli;
261 
262 err:
263 	return NULL;
264 }
265 
266 int d40_phy_sg_to_lli(struct scatterlist *sg,
267 		      int sg_len,
268 		      dma_addr_t target,
269 		      struct d40_phy_lli *lli_sg,
270 		      dma_addr_t lli_phys,
271 		      u32 reg_cfg,
272 		      struct stedma40_half_channel_info *info,
273 		      struct stedma40_half_channel_info *otherinfo,
274 		      unsigned long flags)
275 {
276 	int total_size = 0;
277 	int i;
278 	struct scatterlist *current_sg = sg;
279 	struct d40_phy_lli *lli = lli_sg;
280 	dma_addr_t l_phys = lli_phys;
281 
282 	if (!target)
283 		flags |= LLI_ADDR_INC;
284 
285 	for_each_sg(sg, current_sg, sg_len, i) {
286 		dma_addr_t sg_addr = sg_dma_address(current_sg);
287 		unsigned int len = sg_dma_len(current_sg);
288 		dma_addr_t dst = target ?: sg_addr;
289 
290 		total_size += sg_dma_len(current_sg);
291 
292 		if (i == sg_len - 1)
293 			flags |= LLI_TERM_INT | LLI_LAST_LINK;
294 
295 		l_phys = ALIGN(lli_phys + (lli - lli_sg) *
296 			       sizeof(struct d40_phy_lli), D40_LLI_ALIGN);
297 
298 		lli = d40_phy_buf_to_lli(lli, dst, len, l_phys, lli_phys,
299 					 reg_cfg, info, otherinfo, flags);
300 
301 		if (lli == NULL)
302 			return -EINVAL;
303 	}
304 
305 	return total_size;
306 }
307 
308 
309 /* DMA logical lli operations */
310 
311 static void d40_log_lli_link(struct d40_log_lli *lli_dst,
312 			     struct d40_log_lli *lli_src,
313 			     int next, unsigned int flags)
314 {
315 	bool interrupt = flags & LLI_TERM_INT;
316 	u32 slos = 0;
317 	u32 dlos = 0;
318 
319 	if (next != -EINVAL) {
320 		slos = next * 2;
321 		dlos = next * 2 + 1;
322 	}
323 
324 	if (interrupt) {
325 		lli_dst->lcsp13 |= D40_MEM_LCSP1_SCFG_TIM_MASK;
326 		lli_dst->lcsp13 |= D40_MEM_LCSP3_DTCP_MASK;
327 	}
328 
329 	lli_src->lcsp13 = (lli_src->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
330 		(slos << D40_MEM_LCSP1_SLOS_POS);
331 
332 	lli_dst->lcsp13 = (lli_dst->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
333 		(dlos << D40_MEM_LCSP1_SLOS_POS);
334 }
335 
336 void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
337 			   struct d40_log_lli *lli_dst,
338 			   struct d40_log_lli *lli_src,
339 			   int next, unsigned int flags)
340 {
341 	d40_log_lli_link(lli_dst, lli_src, next, flags);
342 
343 	writel_relaxed(lli_src->lcsp02, &lcpa[0].lcsp0);
344 	writel_relaxed(lli_src->lcsp13, &lcpa[0].lcsp1);
345 	writel_relaxed(lli_dst->lcsp02, &lcpa[0].lcsp2);
346 	writel_relaxed(lli_dst->lcsp13, &lcpa[0].lcsp3);
347 }
348 
349 void d40_log_lli_lcla_write(struct d40_log_lli *lcla,
350 			   struct d40_log_lli *lli_dst,
351 			   struct d40_log_lli *lli_src,
352 			   int next, unsigned int flags)
353 {
354 	d40_log_lli_link(lli_dst, lli_src, next, flags);
355 
356 	writel_relaxed(lli_src->lcsp02, &lcla[0].lcsp02);
357 	writel_relaxed(lli_src->lcsp13, &lcla[0].lcsp13);
358 	writel_relaxed(lli_dst->lcsp02, &lcla[1].lcsp02);
359 	writel_relaxed(lli_dst->lcsp13, &lcla[1].lcsp13);
360 }
361 
362 static void d40_log_fill_lli(struct d40_log_lli *lli,
363 			     dma_addr_t data, u32 data_size,
364 			     u32 reg_cfg,
365 			     u32 data_width,
366 			     unsigned int flags)
367 {
368 	bool addr_inc = flags & LLI_ADDR_INC;
369 
370 	lli->lcsp13 = reg_cfg;
371 
372 	/* The number of elements to transfer */
373 	lli->lcsp02 = ((data_size / data_width) <<
374 		       D40_MEM_LCSP0_ECNT_POS) & D40_MEM_LCSP0_ECNT_MASK;
375 
376 	BUG_ON((data_size / data_width) > STEDMA40_MAX_SEG_SIZE);
377 
378 	/* 16 LSBs address of the current element */
379 	lli->lcsp02 |= data & D40_MEM_LCSP0_SPTR_MASK;
380 	/* 16 MSBs address of the current element */
381 	lli->lcsp13 |= data & D40_MEM_LCSP1_SPTR_MASK;
382 
383 	if (addr_inc)
384 		lli->lcsp13 |= D40_MEM_LCSP1_SCFG_INCR_MASK;
385 
386 }
387 
388 static struct d40_log_lli *d40_log_buf_to_lli(struct d40_log_lli *lli_sg,
389 				       dma_addr_t addr,
390 				       int size,
391 				       u32 lcsp13, /* src or dst*/
392 				       u32 data_width1,
393 				       u32 data_width2,
394 				       unsigned int flags)
395 {
396 	bool addr_inc = flags & LLI_ADDR_INC;
397 	struct d40_log_lli *lli = lli_sg;
398 	int size_rest = size;
399 	int size_seg = 0;
400 
401 	do {
402 		size_seg = d40_seg_size(size_rest, data_width1, data_width2);
403 		size_rest -= size_seg;
404 
405 		d40_log_fill_lli(lli,
406 				 addr,
407 				 size_seg,
408 				 lcsp13, data_width1,
409 				 flags);
410 		if (addr_inc)
411 			addr += size_seg;
412 		lli++;
413 	} while (size_rest);
414 
415 	return lli;
416 }
417 
418 int d40_log_sg_to_lli(struct scatterlist *sg,
419 		      int sg_len,
420 		      dma_addr_t dev_addr,
421 		      struct d40_log_lli *lli_sg,
422 		      u32 lcsp13, /* src or dst*/
423 		      u32 data_width1, u32 data_width2)
424 {
425 	int total_size = 0;
426 	struct scatterlist *current_sg = sg;
427 	int i;
428 	struct d40_log_lli *lli = lli_sg;
429 	unsigned long flags = 0;
430 
431 	if (!dev_addr)
432 		flags |= LLI_ADDR_INC;
433 
434 	for_each_sg(sg, current_sg, sg_len, i) {
435 		dma_addr_t sg_addr = sg_dma_address(current_sg);
436 		unsigned int len = sg_dma_len(current_sg);
437 		dma_addr_t addr = dev_addr ?: sg_addr;
438 
439 		total_size += sg_dma_len(current_sg);
440 
441 		lli = d40_log_buf_to_lli(lli, addr, len,
442 					 lcsp13,
443 					 data_width1,
444 					 data_width2,
445 					 flags);
446 	}
447 
448 	return total_size;
449 }
450