xref: /openbmc/linux/drivers/dma/ste_dma40_ll.c (revision 63dc02bd)
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 <plat/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 	} else {
106 		/* Logical channel */
107 		dst |= 1 << D40_SREG_CFG_LOG_GIM_POS;
108 		src |= 1 << D40_SREG_CFG_LOG_GIM_POS;
109 	}
110 
111 	if (cfg->high_priority) {
112 		src |= 1 << D40_SREG_CFG_PRI_POS;
113 		dst |= 1 << D40_SREG_CFG_PRI_POS;
114 	}
115 
116 	if (cfg->src_info.big_endian)
117 		src |= 1 << D40_SREG_CFG_LBE_POS;
118 	if (cfg->dst_info.big_endian)
119 		dst |= 1 << D40_SREG_CFG_LBE_POS;
120 
121 	*src_cfg = src;
122 	*dst_cfg = dst;
123 }
124 
125 static int d40_phy_fill_lli(struct d40_phy_lli *lli,
126 			    dma_addr_t data,
127 			    u32 data_size,
128 			    dma_addr_t next_lli,
129 			    u32 reg_cfg,
130 			    struct stedma40_half_channel_info *info,
131 			    unsigned int flags)
132 {
133 	bool addr_inc = flags & LLI_ADDR_INC;
134 	bool term_int = flags & LLI_TERM_INT;
135 	unsigned int data_width = info->data_width;
136 	int psize = info->psize;
137 	int num_elems;
138 
139 	if (psize == STEDMA40_PSIZE_PHY_1)
140 		num_elems = 1;
141 	else
142 		num_elems = 2 << psize;
143 
144 	/* Must be aligned */
145 	if (!IS_ALIGNED(data, 0x1 << data_width))
146 		return -EINVAL;
147 
148 	/* Transfer size can't be smaller than (num_elms * elem_size) */
149 	if (data_size < num_elems * (0x1 << data_width))
150 		return -EINVAL;
151 
152 	/* The number of elements. IE now many chunks */
153 	lli->reg_elt = (data_size >> data_width) << D40_SREG_ELEM_PHY_ECNT_POS;
154 
155 	/*
156 	 * Distance to next element sized entry.
157 	 * Usually the size of the element unless you want gaps.
158 	 */
159 	if (addr_inc)
160 		lli->reg_elt |= (0x1 << data_width) <<
161 			D40_SREG_ELEM_PHY_EIDX_POS;
162 
163 	/* Where the data is */
164 	lli->reg_ptr = data;
165 	lli->reg_cfg = reg_cfg;
166 
167 	/* If this scatter list entry is the last one, no next link */
168 	if (next_lli == 0)
169 		lli->reg_lnk = 0x1 << D40_SREG_LNK_PHY_TCP_POS;
170 	else
171 		lli->reg_lnk = next_lli;
172 
173 	/* Set/clear interrupt generation on this link item.*/
174 	if (term_int)
175 		lli->reg_cfg |= 0x1 << D40_SREG_CFG_TIM_POS;
176 	else
177 		lli->reg_cfg &= ~(0x1 << D40_SREG_CFG_TIM_POS);
178 
179 	/* Post link */
180 	lli->reg_lnk |= 0 << D40_SREG_LNK_PHY_PRE_POS;
181 
182 	return 0;
183 }
184 
185 static int d40_seg_size(int size, int data_width1, int data_width2)
186 {
187 	u32 max_w = max(data_width1, data_width2);
188 	u32 min_w = min(data_width1, data_width2);
189 	u32 seg_max = ALIGN(STEDMA40_MAX_SEG_SIZE << min_w, 1 << max_w);
190 
191 	if (seg_max > STEDMA40_MAX_SEG_SIZE)
192 		seg_max -= (1 << max_w);
193 
194 	if (size <= seg_max)
195 		return size;
196 
197 	if (size <= 2 * seg_max)
198 		return ALIGN(size / 2, 1 << max_w);
199 
200 	return seg_max;
201 }
202 
203 static struct d40_phy_lli *
204 d40_phy_buf_to_lli(struct d40_phy_lli *lli, dma_addr_t addr, u32 size,
205 		   dma_addr_t lli_phys, dma_addr_t first_phys, u32 reg_cfg,
206 		   struct stedma40_half_channel_info *info,
207 		   struct stedma40_half_channel_info *otherinfo,
208 		   unsigned long flags)
209 {
210 	bool lastlink = flags & LLI_LAST_LINK;
211 	bool addr_inc = flags & LLI_ADDR_INC;
212 	bool term_int = flags & LLI_TERM_INT;
213 	bool cyclic = flags & LLI_CYCLIC;
214 	int err;
215 	dma_addr_t next = lli_phys;
216 	int size_rest = size;
217 	int size_seg = 0;
218 
219 	/*
220 	 * This piece may be split up based on d40_seg_size(); we only want the
221 	 * term int on the last part.
222 	 */
223 	if (term_int)
224 		flags &= ~LLI_TERM_INT;
225 
226 	do {
227 		size_seg = d40_seg_size(size_rest, info->data_width,
228 					otherinfo->data_width);
229 		size_rest -= size_seg;
230 
231 		if (size_rest == 0 && term_int)
232 			flags |= LLI_TERM_INT;
233 
234 		if (size_rest == 0 && lastlink)
235 			next = cyclic ? first_phys : 0;
236 		else
237 			next = ALIGN(next + sizeof(struct d40_phy_lli),
238 				     D40_LLI_ALIGN);
239 
240 		err = d40_phy_fill_lli(lli, addr, size_seg, next,
241 				       reg_cfg, info, flags);
242 
243 		if (err)
244 			goto err;
245 
246 		lli++;
247 		if (addr_inc)
248 			addr += size_seg;
249 	} while (size_rest);
250 
251 	return lli;
252 
253  err:
254 	return NULL;
255 }
256 
257 int d40_phy_sg_to_lli(struct scatterlist *sg,
258 		      int sg_len,
259 		      dma_addr_t target,
260 		      struct d40_phy_lli *lli_sg,
261 		      dma_addr_t lli_phys,
262 		      u32 reg_cfg,
263 		      struct stedma40_half_channel_info *info,
264 		      struct stedma40_half_channel_info *otherinfo,
265 		      unsigned long flags)
266 {
267 	int total_size = 0;
268 	int i;
269 	struct scatterlist *current_sg = sg;
270 	struct d40_phy_lli *lli = lli_sg;
271 	dma_addr_t l_phys = lli_phys;
272 
273 	if (!target)
274 		flags |= LLI_ADDR_INC;
275 
276 	for_each_sg(sg, current_sg, sg_len, i) {
277 		dma_addr_t sg_addr = sg_dma_address(current_sg);
278 		unsigned int len = sg_dma_len(current_sg);
279 		dma_addr_t dst = target ?: sg_addr;
280 
281 		total_size += sg_dma_len(current_sg);
282 
283 		if (i == sg_len - 1)
284 			flags |= LLI_TERM_INT | LLI_LAST_LINK;
285 
286 		l_phys = ALIGN(lli_phys + (lli - lli_sg) *
287 			       sizeof(struct d40_phy_lli), D40_LLI_ALIGN);
288 
289 		lli = d40_phy_buf_to_lli(lli, dst, len, l_phys, lli_phys,
290 					 reg_cfg, info, otherinfo, flags);
291 
292 		if (lli == NULL)
293 			return -EINVAL;
294 	}
295 
296 	return total_size;
297 }
298 
299 
300 /* DMA logical lli operations */
301 
302 static void d40_log_lli_link(struct d40_log_lli *lli_dst,
303 			     struct d40_log_lli *lli_src,
304 			     int next, unsigned int flags)
305 {
306 	bool interrupt = flags & LLI_TERM_INT;
307 	u32 slos = 0;
308 	u32 dlos = 0;
309 
310 	if (next != -EINVAL) {
311 		slos = next * 2;
312 		dlos = next * 2 + 1;
313 	}
314 
315 	if (interrupt) {
316 		lli_dst->lcsp13 |= D40_MEM_LCSP1_SCFG_TIM_MASK;
317 		lli_dst->lcsp13 |= D40_MEM_LCSP3_DTCP_MASK;
318 	}
319 
320 	lli_src->lcsp13 = (lli_src->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
321 		(slos << D40_MEM_LCSP1_SLOS_POS);
322 
323 	lli_dst->lcsp13 = (lli_dst->lcsp13 & ~D40_MEM_LCSP1_SLOS_MASK) |
324 		(dlos << D40_MEM_LCSP1_SLOS_POS);
325 }
326 
327 void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
328 			   struct d40_log_lli *lli_dst,
329 			   struct d40_log_lli *lli_src,
330 			   int next, unsigned int flags)
331 {
332 	d40_log_lli_link(lli_dst, lli_src, next, flags);
333 
334 	writel(lli_src->lcsp02, &lcpa[0].lcsp0);
335 	writel(lli_src->lcsp13, &lcpa[0].lcsp1);
336 	writel(lli_dst->lcsp02, &lcpa[0].lcsp2);
337 	writel(lli_dst->lcsp13, &lcpa[0].lcsp3);
338 }
339 
340 void d40_log_lli_lcla_write(struct d40_log_lli *lcla,
341 			   struct d40_log_lli *lli_dst,
342 			   struct d40_log_lli *lli_src,
343 			   int next, unsigned int flags)
344 {
345 	d40_log_lli_link(lli_dst, lli_src, next, flags);
346 
347 	writel(lli_src->lcsp02, &lcla[0].lcsp02);
348 	writel(lli_src->lcsp13, &lcla[0].lcsp13);
349 	writel(lli_dst->lcsp02, &lcla[1].lcsp02);
350 	writel(lli_dst->lcsp13, &lcla[1].lcsp13);
351 }
352 
353 static void d40_log_fill_lli(struct d40_log_lli *lli,
354 			     dma_addr_t data, u32 data_size,
355 			     u32 reg_cfg,
356 			     u32 data_width,
357 			     unsigned int flags)
358 {
359 	bool addr_inc = flags & LLI_ADDR_INC;
360 
361 	lli->lcsp13 = reg_cfg;
362 
363 	/* The number of elements to transfer */
364 	lli->lcsp02 = ((data_size >> data_width) <<
365 		       D40_MEM_LCSP0_ECNT_POS) & D40_MEM_LCSP0_ECNT_MASK;
366 
367 	BUG_ON((data_size >> data_width) > STEDMA40_MAX_SEG_SIZE);
368 
369 	/* 16 LSBs address of the current element */
370 	lli->lcsp02 |= data & D40_MEM_LCSP0_SPTR_MASK;
371 	/* 16 MSBs address of the current element */
372 	lli->lcsp13 |= data & D40_MEM_LCSP1_SPTR_MASK;
373 
374 	if (addr_inc)
375 		lli->lcsp13 |= D40_MEM_LCSP1_SCFG_INCR_MASK;
376 
377 }
378 
379 static struct d40_log_lli *d40_log_buf_to_lli(struct d40_log_lli *lli_sg,
380 				       dma_addr_t addr,
381 				       int size,
382 				       u32 lcsp13, /* src or dst*/
383 				       u32 data_width1,
384 				       u32 data_width2,
385 				       unsigned int flags)
386 {
387 	bool addr_inc = flags & LLI_ADDR_INC;
388 	struct d40_log_lli *lli = lli_sg;
389 	int size_rest = size;
390 	int size_seg = 0;
391 
392 	do {
393 		size_seg = d40_seg_size(size_rest, data_width1, data_width2);
394 		size_rest -= size_seg;
395 
396 		d40_log_fill_lli(lli,
397 				 addr,
398 				 size_seg,
399 				 lcsp13, data_width1,
400 				 flags);
401 		if (addr_inc)
402 			addr += size_seg;
403 		lli++;
404 	} while (size_rest);
405 
406 	return lli;
407 }
408 
409 int d40_log_sg_to_lli(struct scatterlist *sg,
410 		      int sg_len,
411 		      dma_addr_t dev_addr,
412 		      struct d40_log_lli *lli_sg,
413 		      u32 lcsp13, /* src or dst*/
414 		      u32 data_width1, u32 data_width2)
415 {
416 	int total_size = 0;
417 	struct scatterlist *current_sg = sg;
418 	int i;
419 	struct d40_log_lli *lli = lli_sg;
420 	unsigned long flags = 0;
421 
422 	if (!dev_addr)
423 		flags |= LLI_ADDR_INC;
424 
425 	for_each_sg(sg, current_sg, sg_len, i) {
426 		dma_addr_t sg_addr = sg_dma_address(current_sg);
427 		unsigned int len = sg_dma_len(current_sg);
428 		dma_addr_t addr = dev_addr ?: sg_addr;
429 
430 		total_size += sg_dma_len(current_sg);
431 
432 		lli = d40_log_buf_to_lli(lli, addr, len,
433 					 lcsp13,
434 					 data_width1,
435 					 data_width2,
436 					 flags);
437 	}
438 
439 	return total_size;
440 }
441