xref: /openbmc/linux/drivers/dma/ste_dma40_ll.c (revision f35e839a)
1 /*
2  * Copyright (C) ST-Ericsson SA 2007-2010
3  * Author: Per Forlin <per.forlin@stericsson.com> for ST-Ericsson
4  * Author: Jonas Aaberg <jonas.aberg@stericsson.com> for ST-Ericsson
5  * License terms: GNU General Public License (GPL) version 2
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 /* Sets up proper LCSP1 and LCSP3 register for a logical channel */
14 void d40_log_cfg(struct stedma40_chan_cfg *cfg,
15 		 u32 *lcsp1, u32 *lcsp3)
16 {
17 	u32 l3 = 0; /* dst */
18 	u32 l1 = 0; /* src */
19 
20 	/* src is mem? -> increase address pos */
21 	if (cfg->dir ==  STEDMA40_MEM_TO_PERIPH ||
22 	    cfg->dir ==  STEDMA40_MEM_TO_MEM)
23 		l1 |= 1 << D40_MEM_LCSP1_SCFG_INCR_POS;
24 
25 	/* dst is mem? -> increase address pos */
26 	if (cfg->dir ==  STEDMA40_PERIPH_TO_MEM ||
27 	    cfg->dir ==  STEDMA40_MEM_TO_MEM)
28 		l3 |= 1 << D40_MEM_LCSP3_DCFG_INCR_POS;
29 
30 	/* src is hw? -> master port 1 */
31 	if (cfg->dir ==  STEDMA40_PERIPH_TO_MEM ||
32 	    cfg->dir ==  STEDMA40_PERIPH_TO_PERIPH)
33 		l1 |= 1 << D40_MEM_LCSP1_SCFG_MST_POS;
34 
35 	/* dst is hw? -> master port 1 */
36 	if (cfg->dir ==  STEDMA40_MEM_TO_PERIPH ||
37 	    cfg->dir ==  STEDMA40_PERIPH_TO_PERIPH)
38 		l3 |= 1 << D40_MEM_LCSP3_DCFG_MST_POS;
39 
40 	l3 |= 1 << D40_MEM_LCSP3_DCFG_EIM_POS;
41 	l3 |= cfg->dst_info.psize << D40_MEM_LCSP3_DCFG_PSIZE_POS;
42 	l3 |= cfg->dst_info.data_width << D40_MEM_LCSP3_DCFG_ESIZE_POS;
43 
44 	l1 |= 1 << D40_MEM_LCSP1_SCFG_EIM_POS;
45 	l1 |= cfg->src_info.psize << D40_MEM_LCSP1_SCFG_PSIZE_POS;
46 	l1 |= cfg->src_info.data_width << D40_MEM_LCSP1_SCFG_ESIZE_POS;
47 
48 	*lcsp1 = l1;
49 	*lcsp3 = l3;
50 
51 }
52 
53 /* Sets up SRC and DST CFG register for both logical and physical channels */
54 void d40_phy_cfg(struct stedma40_chan_cfg *cfg,
55 		 u32 *src_cfg, u32 *dst_cfg, bool is_log)
56 {
57 	u32 src = 0;
58 	u32 dst = 0;
59 
60 	if (!is_log) {
61 		/* Physical channel */
62 		if ((cfg->dir ==  STEDMA40_PERIPH_TO_MEM) ||
63 		    (cfg->dir == STEDMA40_PERIPH_TO_PERIPH)) {
64 			/* Set master port to 1 */
65 			src |= 1 << D40_SREG_CFG_MST_POS;
66 			src |= D40_TYPE_TO_EVENT(cfg->src_dev_type);
67 
68 			if (cfg->src_info.flow_ctrl == STEDMA40_NO_FLOW_CTRL)
69 				src |= 1 << D40_SREG_CFG_PHY_TM_POS;
70 			else
71 				src |= 3 << D40_SREG_CFG_PHY_TM_POS;
72 		}
73 		if ((cfg->dir ==  STEDMA40_MEM_TO_PERIPH) ||
74 		    (cfg->dir == STEDMA40_PERIPH_TO_PERIPH)) {
75 			/* Set master port to 1 */
76 			dst |= 1 << D40_SREG_CFG_MST_POS;
77 			dst |= D40_TYPE_TO_EVENT(cfg->dst_dev_type);
78 
79 			if (cfg->dst_info.flow_ctrl == STEDMA40_NO_FLOW_CTRL)
80 				dst |= 1 << D40_SREG_CFG_PHY_TM_POS;
81 			else
82 				dst |= 3 << D40_SREG_CFG_PHY_TM_POS;
83 		}
84 		/* Interrupt on end of transfer for destination */
85 		dst |= 1 << D40_SREG_CFG_TIM_POS;
86 
87 		/* Generate interrupt on error */
88 		src |= 1 << D40_SREG_CFG_EIM_POS;
89 		dst |= 1 << D40_SREG_CFG_EIM_POS;
90 
91 		/* PSIZE */
92 		if (cfg->src_info.psize != STEDMA40_PSIZE_PHY_1) {
93 			src |= 1 << D40_SREG_CFG_PHY_PEN_POS;
94 			src |= cfg->src_info.psize << D40_SREG_CFG_PSIZE_POS;
95 		}
96 		if (cfg->dst_info.psize != STEDMA40_PSIZE_PHY_1) {
97 			dst |= 1 << D40_SREG_CFG_PHY_PEN_POS;
98 			dst |= cfg->dst_info.psize << D40_SREG_CFG_PSIZE_POS;
99 		}
100 
101 		/* Element size */
102 		src |= cfg->src_info.data_width << D40_SREG_CFG_ESIZE_POS;
103 		dst |= cfg->dst_info.data_width << D40_SREG_CFG_ESIZE_POS;
104 
105 		/* Set the priority bit to high for the physical channel */
106 		if (cfg->high_priority) {
107 			src |= 1 << D40_SREG_CFG_PRI_POS;
108 			dst |= 1 << D40_SREG_CFG_PRI_POS;
109 		}
110 
111 	} else {
112 		/* Logical channel */
113 		dst |= 1 << D40_SREG_CFG_LOG_GIM_POS;
114 		src |= 1 << D40_SREG_CFG_LOG_GIM_POS;
115 	}
116 
117 	if (cfg->src_info.big_endian)
118 		src |= 1 << D40_SREG_CFG_LBE_POS;
119 	if (cfg->dst_info.big_endian)
120 		dst |= 1 << D40_SREG_CFG_LBE_POS;
121 
122 	*src_cfg = src;
123 	*dst_cfg = dst;
124 }
125 
126 static int d40_phy_fill_lli(struct d40_phy_lli *lli,
127 			    dma_addr_t data,
128 			    u32 data_size,
129 			    dma_addr_t next_lli,
130 			    u32 reg_cfg,
131 			    struct stedma40_half_channel_info *info,
132 			    unsigned int flags)
133 {
134 	bool addr_inc = flags & LLI_ADDR_INC;
135 	bool term_int = flags & LLI_TERM_INT;
136 	unsigned int data_width = info->data_width;
137 	int psize = info->psize;
138 	int num_elems;
139 
140 	if (psize == STEDMA40_PSIZE_PHY_1)
141 		num_elems = 1;
142 	else
143 		num_elems = 2 << psize;
144 
145 	/* Must be aligned */
146 	if (!IS_ALIGNED(data, 0x1 << data_width))
147 		return -EINVAL;
148 
149 	/* Transfer size can't be smaller than (num_elms * elem_size) */
150 	if (data_size < num_elems * (0x1 << data_width))
151 		return -EINVAL;
152 
153 	/* The number of elements. IE now many chunks */
154 	lli->reg_elt = (data_size >> data_width) << D40_SREG_ELEM_PHY_ECNT_POS;
155 
156 	/*
157 	 * Distance to next element sized entry.
158 	 * Usually the size of the element unless you want gaps.
159 	 */
160 	if (addr_inc)
161 		lli->reg_elt |= (0x1 << data_width) <<
162 			D40_SREG_ELEM_PHY_EIDX_POS;
163 
164 	/* Where the data is */
165 	lli->reg_ptr = data;
166 	lli->reg_cfg = reg_cfg;
167 
168 	/* If this scatter list entry is the last one, no next link */
169 	if (next_lli == 0)
170 		lli->reg_lnk = 0x1 << D40_SREG_LNK_PHY_TCP_POS;
171 	else
172 		lli->reg_lnk = next_lli;
173 
174 	/* Set/clear interrupt generation on this link item.*/
175 	if (term_int)
176 		lli->reg_cfg |= 0x1 << D40_SREG_CFG_TIM_POS;
177 	else
178 		lli->reg_cfg &= ~(0x1 << D40_SREG_CFG_TIM_POS);
179 
180 	/* Post link */
181 	lli->reg_lnk |= 0 << D40_SREG_LNK_PHY_PRE_POS;
182 
183 	return 0;
184 }
185 
186 static int d40_seg_size(int size, int data_width1, int data_width2)
187 {
188 	u32 max_w = max(data_width1, data_width2);
189 	u32 min_w = min(data_width1, data_width2);
190 	u32 seg_max = ALIGN(STEDMA40_MAX_SEG_SIZE << min_w, 1 << max_w);
191 
192 	if (seg_max > STEDMA40_MAX_SEG_SIZE)
193 		seg_max -= (1 << max_w);
194 
195 	if (size <= seg_max)
196 		return size;
197 
198 	if (size <= 2 * seg_max)
199 		return ALIGN(size / 2, 1 << max_w);
200 
201 	return seg_max;
202 }
203 
204 static struct d40_phy_lli *
205 d40_phy_buf_to_lli(struct d40_phy_lli *lli, dma_addr_t addr, u32 size,
206 		   dma_addr_t lli_phys, dma_addr_t first_phys, u32 reg_cfg,
207 		   struct stedma40_half_channel_info *info,
208 		   struct stedma40_half_channel_info *otherinfo,
209 		   unsigned long flags)
210 {
211 	bool lastlink = flags & LLI_LAST_LINK;
212 	bool addr_inc = flags & LLI_ADDR_INC;
213 	bool term_int = flags & LLI_TERM_INT;
214 	bool cyclic = flags & LLI_CYCLIC;
215 	int err;
216 	dma_addr_t next = lli_phys;
217 	int size_rest = size;
218 	int size_seg = 0;
219 
220 	/*
221 	 * This piece may be split up based on d40_seg_size(); we only want the
222 	 * term int on the last part.
223 	 */
224 	if (term_int)
225 		flags &= ~LLI_TERM_INT;
226 
227 	do {
228 		size_seg = d40_seg_size(size_rest, info->data_width,
229 					otherinfo->data_width);
230 		size_rest -= size_seg;
231 
232 		if (size_rest == 0 && term_int)
233 			flags |= LLI_TERM_INT;
234 
235 		if (size_rest == 0 && lastlink)
236 			next = cyclic ? first_phys : 0;
237 		else
238 			next = ALIGN(next + sizeof(struct d40_phy_lli),
239 				     D40_LLI_ALIGN);
240 
241 		err = d40_phy_fill_lli(lli, addr, size_seg, next,
242 				       reg_cfg, info, flags);
243 
244 		if (err)
245 			goto err;
246 
247 		lli++;
248 		if (addr_inc)
249 			addr += size_seg;
250 	} while (size_rest);
251 
252 	return lli;
253 
254 err:
255 	return NULL;
256 }
257 
258 int d40_phy_sg_to_lli(struct scatterlist *sg,
259 		      int sg_len,
260 		      dma_addr_t target,
261 		      struct d40_phy_lli *lli_sg,
262 		      dma_addr_t lli_phys,
263 		      u32 reg_cfg,
264 		      struct stedma40_half_channel_info *info,
265 		      struct stedma40_half_channel_info *otherinfo,
266 		      unsigned long flags)
267 {
268 	int total_size = 0;
269 	int i;
270 	struct scatterlist *current_sg = sg;
271 	struct d40_phy_lli *lli = lli_sg;
272 	dma_addr_t l_phys = lli_phys;
273 
274 	if (!target)
275 		flags |= LLI_ADDR_INC;
276 
277 	for_each_sg(sg, current_sg, sg_len, i) {
278 		dma_addr_t sg_addr = sg_dma_address(current_sg);
279 		unsigned int len = sg_dma_len(current_sg);
280 		dma_addr_t dst = target ?: sg_addr;
281 
282 		total_size += sg_dma_len(current_sg);
283 
284 		if (i == sg_len - 1)
285 			flags |= LLI_TERM_INT | LLI_LAST_LINK;
286 
287 		l_phys = ALIGN(lli_phys + (lli - lli_sg) *
288 			       sizeof(struct d40_phy_lli), D40_LLI_ALIGN);
289 
290 		lli = d40_phy_buf_to_lli(lli, dst, len, l_phys, lli_phys,
291 					 reg_cfg, info, otherinfo, flags);
292 
293 		if (lli == NULL)
294 			return -EINVAL;
295 	}
296 
297 	return total_size;
298 }
299 
300 
301 /* DMA logical lli operations */
302 
303 static void d40_log_lli_link(struct d40_log_lli *lli_dst,
304 			     struct d40_log_lli *lli_src,
305 			     int next, unsigned int flags)
306 {
307 	bool interrupt = flags & LLI_TERM_INT;
308 	u32 slos = 0;
309 	u32 dlos = 0;
310 
311 	if (next != -EINVAL) {
312 		slos = next * 2;
313 		dlos = next * 2 + 1;
314 	}
315 
316 	if (interrupt) {
317 		lli_dst->lcsp13 |= D40_MEM_LCSP1_SCFG_TIM_MASK;
318 		lli_dst->lcsp13 |= D40_MEM_LCSP3_DTCP_MASK;
319 	}
320 
321 	lli_src->lcsp13 = (lli_src->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
322 		(slos << D40_MEM_LCSP1_SLOS_POS);
323 
324 	lli_dst->lcsp13 = (lli_dst->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
325 		(dlos << D40_MEM_LCSP1_SLOS_POS);
326 }
327 
328 void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
329 			   struct d40_log_lli *lli_dst,
330 			   struct d40_log_lli *lli_src,
331 			   int next, unsigned int flags)
332 {
333 	d40_log_lli_link(lli_dst, lli_src, next, flags);
334 
335 	writel_relaxed(lli_src->lcsp02, &lcpa[0].lcsp0);
336 	writel_relaxed(lli_src->lcsp13, &lcpa[0].lcsp1);
337 	writel_relaxed(lli_dst->lcsp02, &lcpa[0].lcsp2);
338 	writel_relaxed(lli_dst->lcsp13, &lcpa[0].lcsp3);
339 }
340 
341 void d40_log_lli_lcla_write(struct d40_log_lli *lcla,
342 			   struct d40_log_lli *lli_dst,
343 			   struct d40_log_lli *lli_src,
344 			   int next, unsigned int flags)
345 {
346 	d40_log_lli_link(lli_dst, lli_src, next, flags);
347 
348 	writel_relaxed(lli_src->lcsp02, &lcla[0].lcsp02);
349 	writel_relaxed(lli_src->lcsp13, &lcla[0].lcsp13);
350 	writel_relaxed(lli_dst->lcsp02, &lcla[1].lcsp02);
351 	writel_relaxed(lli_dst->lcsp13, &lcla[1].lcsp13);
352 }
353 
354 static void d40_log_fill_lli(struct d40_log_lli *lli,
355 			     dma_addr_t data, u32 data_size,
356 			     u32 reg_cfg,
357 			     u32 data_width,
358 			     unsigned int flags)
359 {
360 	bool addr_inc = flags & LLI_ADDR_INC;
361 
362 	lli->lcsp13 = reg_cfg;
363 
364 	/* The number of elements to transfer */
365 	lli->lcsp02 = ((data_size >> data_width) <<
366 		       D40_MEM_LCSP0_ECNT_POS) & D40_MEM_LCSP0_ECNT_MASK;
367 
368 	BUG_ON((data_size >> data_width) > STEDMA40_MAX_SEG_SIZE);
369 
370 	/* 16 LSBs address of the current element */
371 	lli->lcsp02 |= data & D40_MEM_LCSP0_SPTR_MASK;
372 	/* 16 MSBs address of the current element */
373 	lli->lcsp13 |= data & D40_MEM_LCSP1_SPTR_MASK;
374 
375 	if (addr_inc)
376 		lli->lcsp13 |= D40_MEM_LCSP1_SCFG_INCR_MASK;
377 
378 }
379 
380 static struct d40_log_lli *d40_log_buf_to_lli(struct d40_log_lli *lli_sg,
381 				       dma_addr_t addr,
382 				       int size,
383 				       u32 lcsp13, /* src or dst*/
384 				       u32 data_width1,
385 				       u32 data_width2,
386 				       unsigned int flags)
387 {
388 	bool addr_inc = flags & LLI_ADDR_INC;
389 	struct d40_log_lli *lli = lli_sg;
390 	int size_rest = size;
391 	int size_seg = 0;
392 
393 	do {
394 		size_seg = d40_seg_size(size_rest, data_width1, data_width2);
395 		size_rest -= size_seg;
396 
397 		d40_log_fill_lli(lli,
398 				 addr,
399 				 size_seg,
400 				 lcsp13, data_width1,
401 				 flags);
402 		if (addr_inc)
403 			addr += size_seg;
404 		lli++;
405 	} while (size_rest);
406 
407 	return lli;
408 }
409 
410 int d40_log_sg_to_lli(struct scatterlist *sg,
411 		      int sg_len,
412 		      dma_addr_t dev_addr,
413 		      struct d40_log_lli *lli_sg,
414 		      u32 lcsp13, /* src or dst*/
415 		      u32 data_width1, u32 data_width2)
416 {
417 	int total_size = 0;
418 	struct scatterlist *current_sg = sg;
419 	int i;
420 	struct d40_log_lli *lli = lli_sg;
421 	unsigned long flags = 0;
422 
423 	if (!dev_addr)
424 		flags |= LLI_ADDR_INC;
425 
426 	for_each_sg(sg, current_sg, sg_len, i) {
427 		dma_addr_t sg_addr = sg_dma_address(current_sg);
428 		unsigned int len = sg_dma_len(current_sg);
429 		dma_addr_t addr = dev_addr ?: sg_addr;
430 
431 		total_size += sg_dma_len(current_sg);
432 
433 		lli = d40_log_buf_to_lli(lli, addr, len,
434 					 lcsp13,
435 					 data_width1,
436 					 data_width2,
437 					 flags);
438 	}
439 
440 	return total_size;
441 }
442