1 /*
2  * Header file for the Atmel AHB DMA Controller driver
3  *
4  * Copyright (C) 2008 Atmel Corporation
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 #ifndef AT_HDMAC_REGS_H
12 #define	AT_HDMAC_REGS_H
13 
14 #include <linux/platform_data/dma-atmel.h>
15 
16 #define	AT_DMA_MAX_NR_CHANNELS	8
17 
18 
19 #define	AT_DMA_GCFG	0x00	/* Global Configuration Register */
20 #define		AT_DMA_IF_BIGEND(i)	(0x1 << (i))	/* AHB-Lite Interface i in Big-endian mode */
21 #define		AT_DMA_ARB_CFG	(0x1 << 4)	/* Arbiter mode. */
22 #define			AT_DMA_ARB_CFG_FIXED		(0x0 << 4)
23 #define			AT_DMA_ARB_CFG_ROUND_ROBIN	(0x1 << 4)
24 
25 #define	AT_DMA_EN	0x04	/* Controller Enable Register */
26 #define		AT_DMA_ENABLE	(0x1 << 0)
27 
28 #define	AT_DMA_SREQ	0x08	/* Software Single Request Register */
29 #define		AT_DMA_SSREQ(x)	(0x1 << ((x) << 1))		/* Request a source single transfer on channel x */
30 #define		AT_DMA_DSREQ(x)	(0x1 << (1 + ((x) << 1)))	/* Request a destination single transfer on channel x */
31 
32 #define	AT_DMA_CREQ	0x0C	/* Software Chunk Transfer Request Register */
33 #define		AT_DMA_SCREQ(x)	(0x1 << ((x) << 1))		/* Request a source chunk transfer on channel x */
34 #define		AT_DMA_DCREQ(x)	(0x1 << (1 + ((x) << 1)))	/* Request a destination chunk transfer on channel x */
35 
36 #define	AT_DMA_LAST	0x10	/* Software Last Transfer Flag Register */
37 #define		AT_DMA_SLAST(x)	(0x1 << ((x) << 1))		/* This src rq is last tx of buffer on channel x */
38 #define		AT_DMA_DLAST(x)	(0x1 << (1 + ((x) << 1)))	/* This dst rq is last tx of buffer on channel x */
39 
40 #define	AT_DMA_SYNC	0x14	/* Request Synchronization Register */
41 #define		AT_DMA_SYR(h)	(0x1 << (h))			/* Synchronize handshake line h */
42 
43 /* Error, Chained Buffer transfer completed and Buffer transfer completed Interrupt registers */
44 #define	AT_DMA_EBCIER	0x18	/* Enable register */
45 #define	AT_DMA_EBCIDR	0x1C	/* Disable register */
46 #define	AT_DMA_EBCIMR	0x20	/* Mask Register */
47 #define	AT_DMA_EBCISR	0x24	/* Status Register */
48 #define		AT_DMA_CBTC_OFFSET	8
49 #define		AT_DMA_ERR_OFFSET	16
50 #define		AT_DMA_BTC(x)	(0x1 << (x))
51 #define		AT_DMA_CBTC(x)	(0x1 << (AT_DMA_CBTC_OFFSET + (x)))
52 #define		AT_DMA_ERR(x)	(0x1 << (AT_DMA_ERR_OFFSET + (x)))
53 
54 #define	AT_DMA_CHER	0x28	/* Channel Handler Enable Register */
55 #define		AT_DMA_ENA(x)	(0x1 << (x))
56 #define		AT_DMA_SUSP(x)	(0x1 << ( 8 + (x)))
57 #define		AT_DMA_KEEP(x)	(0x1 << (24 + (x)))
58 
59 #define	AT_DMA_CHDR	0x2C	/* Channel Handler Disable Register */
60 #define		AT_DMA_DIS(x)	(0x1 << (x))
61 #define		AT_DMA_RES(x)	(0x1 << ( 8 + (x)))
62 
63 #define	AT_DMA_CHSR	0x30	/* Channel Handler Status Register */
64 #define		AT_DMA_EMPT(x)	(0x1 << (16 + (x)))
65 #define		AT_DMA_STAL(x)	(0x1 << (24 + (x)))
66 
67 
68 #define	AT_DMA_CH_REGS_BASE	0x3C	/* Channel registers base address */
69 #define	ch_regs(x)	(AT_DMA_CH_REGS_BASE + (x) * 0x28) /* Channel x base addr */
70 
71 /* Hardware register offset for each channel */
72 #define	ATC_SADDR_OFFSET	0x00	/* Source Address Register */
73 #define	ATC_DADDR_OFFSET	0x04	/* Destination Address Register */
74 #define	ATC_DSCR_OFFSET		0x08	/* Descriptor Address Register */
75 #define	ATC_CTRLA_OFFSET	0x0C	/* Control A Register */
76 #define	ATC_CTRLB_OFFSET	0x10	/* Control B Register */
77 #define	ATC_CFG_OFFSET		0x14	/* Configuration Register */
78 #define	ATC_SPIP_OFFSET		0x18	/* Src PIP Configuration Register */
79 #define	ATC_DPIP_OFFSET		0x1C	/* Dst PIP Configuration Register */
80 
81 
82 /* Bitfield definitions */
83 
84 /* Bitfields in DSCR */
85 #define	ATC_DSCR_IF(i)		(0x3 & (i))	/* Dsc feched via AHB-Lite Interface i */
86 
87 /* Bitfields in CTRLA */
88 #define	ATC_BTSIZE_MAX		0xFFFFUL	/* Maximum Buffer Transfer Size */
89 #define	ATC_BTSIZE(x)		(ATC_BTSIZE_MAX & (x)) /* Buffer Transfer Size */
90 #define	ATC_SCSIZE_MASK		(0x7 << 16)	/* Source Chunk Transfer Size */
91 #define		ATC_SCSIZE(x)		(ATC_SCSIZE_MASK & ((x) << 16))
92 #define		ATC_SCSIZE_1		(0x0 << 16)
93 #define		ATC_SCSIZE_4		(0x1 << 16)
94 #define		ATC_SCSIZE_8		(0x2 << 16)
95 #define		ATC_SCSIZE_16		(0x3 << 16)
96 #define		ATC_SCSIZE_32		(0x4 << 16)
97 #define		ATC_SCSIZE_64		(0x5 << 16)
98 #define		ATC_SCSIZE_128		(0x6 << 16)
99 #define		ATC_SCSIZE_256		(0x7 << 16)
100 #define	ATC_DCSIZE_MASK		(0x7 << 20)	/* Destination Chunk Transfer Size */
101 #define		ATC_DCSIZE(x)		(ATC_DCSIZE_MASK & ((x) << 20))
102 #define		ATC_DCSIZE_1		(0x0 << 20)
103 #define		ATC_DCSIZE_4		(0x1 << 20)
104 #define		ATC_DCSIZE_8		(0x2 << 20)
105 #define		ATC_DCSIZE_16		(0x3 << 20)
106 #define		ATC_DCSIZE_32		(0x4 << 20)
107 #define		ATC_DCSIZE_64		(0x5 << 20)
108 #define		ATC_DCSIZE_128		(0x6 << 20)
109 #define		ATC_DCSIZE_256		(0x7 << 20)
110 #define	ATC_SRC_WIDTH_MASK	(0x3 << 24)	/* Source Single Transfer Size */
111 #define		ATC_SRC_WIDTH(x)	((x) << 24)
112 #define		ATC_SRC_WIDTH_BYTE	(0x0 << 24)
113 #define		ATC_SRC_WIDTH_HALFWORD	(0x1 << 24)
114 #define		ATC_SRC_WIDTH_WORD	(0x2 << 24)
115 #define		ATC_REG_TO_SRC_WIDTH(r)	(((r) >> 24) & 0x3)
116 #define	ATC_DST_WIDTH_MASK	(0x3 << 28)	/* Destination Single Transfer Size */
117 #define		ATC_DST_WIDTH(x)	((x) << 28)
118 #define		ATC_DST_WIDTH_BYTE	(0x0 << 28)
119 #define		ATC_DST_WIDTH_HALFWORD	(0x1 << 28)
120 #define		ATC_DST_WIDTH_WORD	(0x2 << 28)
121 #define	ATC_DONE		(0x1 << 31)	/* Tx Done (only written back in descriptor) */
122 
123 /* Bitfields in CTRLB */
124 #define	ATC_SIF(i)		(0x3 & (i))	/* Src tx done via AHB-Lite Interface i */
125 #define	ATC_DIF(i)		((0x3 & (i)) <<  4)	/* Dst tx done via AHB-Lite Interface i */
126 				  /* Specify AHB interfaces */
127 #define AT_DMA_MEM_IF		0 /* interface 0 as memory interface */
128 #define AT_DMA_PER_IF		1 /* interface 1 as peripheral interface */
129 
130 #define	ATC_SRC_PIP		(0x1 <<  8)	/* Source Picture-in-Picture enabled */
131 #define	ATC_DST_PIP		(0x1 << 12)	/* Destination Picture-in-Picture enabled */
132 #define	ATC_SRC_DSCR_DIS	(0x1 << 16)	/* Src Descriptor fetch disable */
133 #define	ATC_DST_DSCR_DIS	(0x1 << 20)	/* Dst Descriptor fetch disable */
134 #define	ATC_FC_MASK		(0x7 << 21)	/* Choose Flow Controller */
135 #define		ATC_FC_MEM2MEM		(0x0 << 21)	/* Mem-to-Mem (DMA) */
136 #define		ATC_FC_MEM2PER		(0x1 << 21)	/* Mem-to-Periph (DMA) */
137 #define		ATC_FC_PER2MEM		(0x2 << 21)	/* Periph-to-Mem (DMA) */
138 #define		ATC_FC_PER2PER		(0x3 << 21)	/* Periph-to-Periph (DMA) */
139 #define		ATC_FC_PER2MEM_PER	(0x4 << 21)	/* Periph-to-Mem (Peripheral) */
140 #define		ATC_FC_MEM2PER_PER	(0x5 << 21)	/* Mem-to-Periph (Peripheral) */
141 #define		ATC_FC_PER2PER_SRCPER	(0x6 << 21)	/* Periph-to-Periph (Src Peripheral) */
142 #define		ATC_FC_PER2PER_DSTPER	(0x7 << 21)	/* Periph-to-Periph (Dst Peripheral) */
143 #define	ATC_SRC_ADDR_MODE_MASK	(0x3 << 24)
144 #define		ATC_SRC_ADDR_MODE_INCR	(0x0 << 24)	/* Incrementing Mode */
145 #define		ATC_SRC_ADDR_MODE_DECR	(0x1 << 24)	/* Decrementing Mode */
146 #define		ATC_SRC_ADDR_MODE_FIXED	(0x2 << 24)	/* Fixed Mode */
147 #define	ATC_DST_ADDR_MODE_MASK	(0x3 << 28)
148 #define		ATC_DST_ADDR_MODE_INCR	(0x0 << 28)	/* Incrementing Mode */
149 #define		ATC_DST_ADDR_MODE_DECR	(0x1 << 28)	/* Decrementing Mode */
150 #define		ATC_DST_ADDR_MODE_FIXED	(0x2 << 28)	/* Fixed Mode */
151 #define	ATC_IEN			(0x1 << 30)	/* BTC interrupt enable (active low) */
152 #define	ATC_AUTO		(0x1 << 31)	/* Auto multiple buffer tx enable */
153 
154 /* Bitfields in CFG */
155 /* are in at_hdmac.h */
156 
157 /* Bitfields in SPIP */
158 #define	ATC_SPIP_HOLE(x)	(0xFFFFU & (x))
159 #define	ATC_SPIP_BOUNDARY(x)	((0x3FF & (x)) << 16)
160 
161 /* Bitfields in DPIP */
162 #define	ATC_DPIP_HOLE(x)	(0xFFFFU & (x))
163 #define	ATC_DPIP_BOUNDARY(x)	((0x3FF & (x)) << 16)
164 
165 
166 /*--  descriptors  -----------------------------------------------------*/
167 
168 /* LLI == Linked List Item; aka DMA buffer descriptor */
169 struct at_lli {
170 	/* values that are not changed by hardware */
171 	dma_addr_t	saddr;
172 	dma_addr_t	daddr;
173 	/* value that may get written back: */
174 	u32		ctrla;
175 	/* more values that are not changed by hardware */
176 	u32		ctrlb;
177 	dma_addr_t	dscr;	/* chain to next lli */
178 };
179 
180 /**
181  * struct at_desc - software descriptor
182  * @at_lli: hardware lli structure
183  * @txd: support for the async_tx api
184  * @desc_node: node on the channed descriptors list
185  * @len: descriptor byte count
186  * @total_len: total transaction byte count
187  */
188 struct at_desc {
189 	/* FIRST values the hardware uses */
190 	struct at_lli			lli;
191 
192 	/* THEN values for driver housekeeping */
193 	struct list_head		tx_list;
194 	struct dma_async_tx_descriptor	txd;
195 	struct list_head		desc_node;
196 	size_t				len;
197 	size_t				total_len;
198 
199 	/* Interleaved data */
200 	size_t				boundary;
201 	size_t				dst_hole;
202 	size_t				src_hole;
203 
204 	/* Memset temporary buffer */
205 	bool				memset_buffer;
206 	dma_addr_t			memset_paddr;
207 	int				*memset_vaddr;
208 };
209 
210 static inline struct at_desc *
txd_to_at_desc(struct dma_async_tx_descriptor * txd)211 txd_to_at_desc(struct dma_async_tx_descriptor *txd)
212 {
213 	return container_of(txd, struct at_desc, txd);
214 }
215 
216 
217 /*--  Channels  --------------------------------------------------------*/
218 
219 /**
220  * atc_status - information bits stored in channel status flag
221  *
222  * Manipulated with atomic operations.
223  */
224 enum atc_status {
225 	ATC_IS_ERROR = 0,
226 	ATC_IS_PAUSED = 1,
227 	ATC_IS_CYCLIC = 24,
228 };
229 
230 /**
231  * struct at_dma_chan - internal representation of an Atmel HDMAC channel
232  * @chan_common: common dmaengine channel object members
233  * @device: parent device
234  * @ch_regs: memory mapped register base
235  * @mask: channel index in a mask
236  * @per_if: peripheral interface
237  * @mem_if: memory interface
238  * @status: transmit status information from irq/prep* functions
239  *                to tasklet (use atomic operations)
240  * @tasklet: bottom half to finish transaction work
241  * @save_cfg: configuration register that is saved on suspend/resume cycle
242  * @save_dscr: for cyclic operations, preserve next descriptor address in
243  *             the cyclic list on suspend/resume cycle
244  * @dma_sconfig: configuration for slave transfers, passed via
245  * .device_config
246  * @lock: serializes enqueue/dequeue operations to descriptors lists
247  * @active_list: list of descriptors dmaengine is being running on
248  * @queue: list of descriptors ready to be submitted to engine
249  * @free_list: list of descriptors usable by the channel
250  * @descs_allocated: records the actual size of the descriptor pool
251  */
252 struct at_dma_chan {
253 	struct dma_chan		chan_common;
254 	struct at_dma		*device;
255 	void __iomem		*ch_regs;
256 	u8			mask;
257 	u8			per_if;
258 	u8			mem_if;
259 	unsigned long		status;
260 	struct tasklet_struct	tasklet;
261 	u32			save_cfg;
262 	u32			save_dscr;
263 	struct dma_slave_config dma_sconfig;
264 
265 	spinlock_t		lock;
266 
267 	/* these other elements are all protected by lock */
268 	struct list_head	active_list;
269 	struct list_head	queue;
270 	struct list_head	free_list;
271 	unsigned int		descs_allocated;
272 };
273 
274 #define	channel_readl(atchan, name) \
275 	__raw_readl((atchan)->ch_regs + ATC_##name##_OFFSET)
276 
277 #define	channel_writel(atchan, name, val) \
278 	__raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET)
279 
to_at_dma_chan(struct dma_chan * dchan)280 static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan)
281 {
282 	return container_of(dchan, struct at_dma_chan, chan_common);
283 }
284 
285 /*
286  * Fix sconfig's burst size according to at_hdmac. We need to convert them as:
287  * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7.
288  *
289  * This can be done by finding most significant bit set.
290  */
convert_burst(u32 * maxburst)291 static inline void convert_burst(u32 *maxburst)
292 {
293 	if (*maxburst > 1)
294 		*maxburst = fls(*maxburst) - 2;
295 	else
296 		*maxburst = 0;
297 }
298 
299 /*
300  * Fix sconfig's bus width according to at_hdmac.
301  * 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2.
302  */
convert_buswidth(enum dma_slave_buswidth addr_width)303 static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
304 {
305 	switch (addr_width) {
306 	case DMA_SLAVE_BUSWIDTH_2_BYTES:
307 		return 1;
308 	case DMA_SLAVE_BUSWIDTH_4_BYTES:
309 		return 2;
310 	default:
311 		/* For 1 byte width or fallback */
312 		return 0;
313 	}
314 }
315 
316 /*--  Controller  ------------------------------------------------------*/
317 
318 /**
319  * struct at_dma - internal representation of an Atmel HDMA Controller
320  * @chan_common: common dmaengine dma_device object members
321  * @atdma_devtype: identifier of DMA controller compatibility
322  * @ch_regs: memory mapped register base
323  * @clk: dma controller clock
324  * @save_imr: interrupt mask register that is saved on suspend/resume cycle
325  * @all_chan_mask: all channels availlable in a mask
326  * @dma_desc_pool: base of DMA descriptor region (DMA address)
327  * @chan: channels table to store at_dma_chan structures
328  */
329 struct at_dma {
330 	struct dma_device	dma_common;
331 	void __iomem		*regs;
332 	struct clk		*clk;
333 	u32			save_imr;
334 
335 	u8			all_chan_mask;
336 
337 	struct dma_pool		*dma_desc_pool;
338 	struct dma_pool		*memset_pool;
339 	/* AT THE END channels table */
340 	struct at_dma_chan	chan[0];
341 };
342 
343 #define	dma_readl(atdma, name) \
344 	__raw_readl((atdma)->regs + AT_DMA_##name)
345 #define	dma_writel(atdma, name, val) \
346 	__raw_writel((val), (atdma)->regs + AT_DMA_##name)
347 
to_at_dma(struct dma_device * ddev)348 static inline struct at_dma *to_at_dma(struct dma_device *ddev)
349 {
350 	return container_of(ddev, struct at_dma, dma_common);
351 }
352 
353 
354 /*--  Helper functions  ------------------------------------------------*/
355 
chan2dev(struct dma_chan * chan)356 static struct device *chan2dev(struct dma_chan *chan)
357 {
358 	return &chan->dev->device;
359 }
360 
361 #if defined(VERBOSE_DEBUG)
vdbg_dump_regs(struct at_dma_chan * atchan)362 static void vdbg_dump_regs(struct at_dma_chan *atchan)
363 {
364 	struct at_dma	*atdma = to_at_dma(atchan->chan_common.device);
365 
366 	dev_err(chan2dev(&atchan->chan_common),
367 		"  channel %d : imr = 0x%x, chsr = 0x%x\n",
368 		atchan->chan_common.chan_id,
369 		dma_readl(atdma, EBCIMR),
370 		dma_readl(atdma, CHSR));
371 
372 	dev_err(chan2dev(&atchan->chan_common),
373 		"  channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
374 		channel_readl(atchan, SADDR),
375 		channel_readl(atchan, DADDR),
376 		channel_readl(atchan, CTRLA),
377 		channel_readl(atchan, CTRLB),
378 		channel_readl(atchan, CFG),
379 		channel_readl(atchan, DSCR));
380 }
381 #else
vdbg_dump_regs(struct at_dma_chan * atchan)382 static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
383 #endif
384 
atc_dump_lli(struct at_dma_chan * atchan,struct at_lli * lli)385 static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli)
386 {
387 	dev_crit(chan2dev(&atchan->chan_common),
388 		 "desc: s%pad d%pad ctrl0x%x:0x%x l%pad\n",
389 		 &lli->saddr, &lli->daddr,
390 		 lli->ctrla, lli->ctrlb, &lli->dscr);
391 }
392 
393 
atc_setup_irq(struct at_dma * atdma,int chan_id,int on)394 static void atc_setup_irq(struct at_dma *atdma, int chan_id, int on)
395 {
396 	u32 ebci;
397 
398 	/* enable interrupts on buffer transfer completion & error */
399 	ebci =    AT_DMA_BTC(chan_id)
400 		| AT_DMA_ERR(chan_id);
401 	if (on)
402 		dma_writel(atdma, EBCIER, ebci);
403 	else
404 		dma_writel(atdma, EBCIDR, ebci);
405 }
406 
atc_enable_chan_irq(struct at_dma * atdma,int chan_id)407 static void atc_enable_chan_irq(struct at_dma *atdma, int chan_id)
408 {
409 	atc_setup_irq(atdma, chan_id, 1);
410 }
411 
atc_disable_chan_irq(struct at_dma * atdma,int chan_id)412 static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id)
413 {
414 	atc_setup_irq(atdma, chan_id, 0);
415 }
416 
417 
418 /**
419  * atc_chan_is_enabled - test if given channel is enabled
420  * @atchan: channel we want to test status
421  */
atc_chan_is_enabled(struct at_dma_chan * atchan)422 static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
423 {
424 	struct at_dma	*atdma = to_at_dma(atchan->chan_common.device);
425 
426 	return !!(dma_readl(atdma, CHSR) & atchan->mask);
427 }
428 
429 /**
430  * atc_chan_is_paused - test channel pause/resume status
431  * @atchan: channel we want to test status
432  */
atc_chan_is_paused(struct at_dma_chan * atchan)433 static inline int atc_chan_is_paused(struct at_dma_chan *atchan)
434 {
435 	return test_bit(ATC_IS_PAUSED, &atchan->status);
436 }
437 
438 /**
439  * atc_chan_is_cyclic - test if given channel has cyclic property set
440  * @atchan: channel we want to test status
441  */
atc_chan_is_cyclic(struct at_dma_chan * atchan)442 static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan)
443 {
444 	return test_bit(ATC_IS_CYCLIC, &atchan->status);
445 }
446 
447 /**
448  * set_desc_eol - set end-of-link to descriptor so it will end transfer
449  * @desc: descriptor, signle or at the end of a chain, to end chain on
450  */
set_desc_eol(struct at_desc * desc)451 static void set_desc_eol(struct at_desc *desc)
452 {
453 	u32 ctrlb = desc->lli.ctrlb;
454 
455 	ctrlb &= ~ATC_IEN;
456 	ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS;
457 
458 	desc->lli.ctrlb = ctrlb;
459 	desc->lli.dscr = 0;
460 }
461 
462 #endif /* AT_HDMAC_REGS_H */
463