1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Header file for the Atmel AHB DMA Controller driver
4 *
5 * Copyright (C) 2008 Atmel Corporation
6 */
7#ifndef AT_HDMAC_REGS_H
8#define	AT_HDMAC_REGS_H
9
10#include <linux/platform_data/dma-atmel.h>
11
12#define	AT_DMA_MAX_NR_CHANNELS	8
13
14
15#define	AT_DMA_GCFG	0x00	/* Global Configuration Register */
16#define		AT_DMA_IF_BIGEND(i)	(0x1 << (i))	/* AHB-Lite Interface i in Big-endian mode */
17#define		AT_DMA_ARB_CFG	(0x1 << 4)	/* Arbiter mode. */
18#define			AT_DMA_ARB_CFG_FIXED		(0x0 << 4)
19#define			AT_DMA_ARB_CFG_ROUND_ROBIN	(0x1 << 4)
20
21#define	AT_DMA_EN	0x04	/* Controller Enable Register */
22#define		AT_DMA_ENABLE	(0x1 << 0)
23
24#define	AT_DMA_SREQ	0x08	/* Software Single Request Register */
25#define		AT_DMA_SSREQ(x)	(0x1 << ((x) << 1))		/* Request a source single transfer on channel x */
26#define		AT_DMA_DSREQ(x)	(0x1 << (1 + ((x) << 1)))	/* Request a destination single transfer on channel x */
27
28#define	AT_DMA_CREQ	0x0C	/* Software Chunk Transfer Request Register */
29#define		AT_DMA_SCREQ(x)	(0x1 << ((x) << 1))		/* Request a source chunk transfer on channel x */
30#define		AT_DMA_DCREQ(x)	(0x1 << (1 + ((x) << 1)))	/* Request a destination chunk transfer on channel x */
31
32#define	AT_DMA_LAST	0x10	/* Software Last Transfer Flag Register */
33#define		AT_DMA_SLAST(x)	(0x1 << ((x) << 1))		/* This src rq is last tx of buffer on channel x */
34#define		AT_DMA_DLAST(x)	(0x1 << (1 + ((x) << 1)))	/* This dst rq is last tx of buffer on channel x */
35
36#define	AT_DMA_SYNC	0x14	/* Request Synchronization Register */
37#define		AT_DMA_SYR(h)	(0x1 << (h))			/* Synchronize handshake line h */
38
39/* Error, Chained Buffer transfer completed and Buffer transfer completed Interrupt registers */
40#define	AT_DMA_EBCIER	0x18	/* Enable register */
41#define	AT_DMA_EBCIDR	0x1C	/* Disable register */
42#define	AT_DMA_EBCIMR	0x20	/* Mask Register */
43#define	AT_DMA_EBCISR	0x24	/* Status Register */
44#define		AT_DMA_CBTC_OFFSET	8
45#define		AT_DMA_ERR_OFFSET	16
46#define		AT_DMA_BTC(x)	(0x1 << (x))
47#define		AT_DMA_CBTC(x)	(0x1 << (AT_DMA_CBTC_OFFSET + (x)))
48#define		AT_DMA_ERR(x)	(0x1 << (AT_DMA_ERR_OFFSET + (x)))
49
50#define	AT_DMA_CHER	0x28	/* Channel Handler Enable Register */
51#define		AT_DMA_ENA(x)	(0x1 << (x))
52#define		AT_DMA_SUSP(x)	(0x1 << ( 8 + (x)))
53#define		AT_DMA_KEEP(x)	(0x1 << (24 + (x)))
54
55#define	AT_DMA_CHDR	0x2C	/* Channel Handler Disable Register */
56#define		AT_DMA_DIS(x)	(0x1 << (x))
57#define		AT_DMA_RES(x)	(0x1 << ( 8 + (x)))
58
59#define	AT_DMA_CHSR	0x30	/* Channel Handler Status Register */
60#define		AT_DMA_EMPT(x)	(0x1 << (16 + (x)))
61#define		AT_DMA_STAL(x)	(0x1 << (24 + (x)))
62
63
64#define	AT_DMA_CH_REGS_BASE	0x3C	/* Channel registers base address */
65#define	ch_regs(x)	(AT_DMA_CH_REGS_BASE + (x) * 0x28) /* Channel x base addr */
66
67/* Hardware register offset for each channel */
68#define	ATC_SADDR_OFFSET	0x00	/* Source Address Register */
69#define	ATC_DADDR_OFFSET	0x04	/* Destination Address Register */
70#define	ATC_DSCR_OFFSET		0x08	/* Descriptor Address Register */
71#define	ATC_CTRLA_OFFSET	0x0C	/* Control A Register */
72#define	ATC_CTRLB_OFFSET	0x10	/* Control B Register */
73#define	ATC_CFG_OFFSET		0x14	/* Configuration Register */
74#define	ATC_SPIP_OFFSET		0x18	/* Src PIP Configuration Register */
75#define	ATC_DPIP_OFFSET		0x1C	/* Dst PIP Configuration Register */
76
77
78/* Bitfield definitions */
79
80/* Bitfields in DSCR */
81#define	ATC_DSCR_IF(i)		(0x3 & (i))	/* Dsc feched via AHB-Lite Interface i */
82
83/* Bitfields in CTRLA */
84#define	ATC_BTSIZE_MAX		0xFFFFUL	/* Maximum Buffer Transfer Size */
85#define	ATC_BTSIZE(x)		(ATC_BTSIZE_MAX & (x)) /* Buffer Transfer Size */
86#define	ATC_SCSIZE_MASK		(0x7 << 16)	/* Source Chunk Transfer Size */
87#define		ATC_SCSIZE(x)		(ATC_SCSIZE_MASK & ((x) << 16))
88#define		ATC_SCSIZE_1		(0x0 << 16)
89#define		ATC_SCSIZE_4		(0x1 << 16)
90#define		ATC_SCSIZE_8		(0x2 << 16)
91#define		ATC_SCSIZE_16		(0x3 << 16)
92#define		ATC_SCSIZE_32		(0x4 << 16)
93#define		ATC_SCSIZE_64		(0x5 << 16)
94#define		ATC_SCSIZE_128		(0x6 << 16)
95#define		ATC_SCSIZE_256		(0x7 << 16)
96#define	ATC_DCSIZE_MASK		(0x7 << 20)	/* Destination Chunk Transfer Size */
97#define		ATC_DCSIZE(x)		(ATC_DCSIZE_MASK & ((x) << 20))
98#define		ATC_DCSIZE_1		(0x0 << 20)
99#define		ATC_DCSIZE_4		(0x1 << 20)
100#define		ATC_DCSIZE_8		(0x2 << 20)
101#define		ATC_DCSIZE_16		(0x3 << 20)
102#define		ATC_DCSIZE_32		(0x4 << 20)
103#define		ATC_DCSIZE_64		(0x5 << 20)
104#define		ATC_DCSIZE_128		(0x6 << 20)
105#define		ATC_DCSIZE_256		(0x7 << 20)
106#define	ATC_SRC_WIDTH_MASK	(0x3 << 24)	/* Source Single Transfer Size */
107#define		ATC_SRC_WIDTH(x)	((x) << 24)
108#define		ATC_SRC_WIDTH_BYTE	(0x0 << 24)
109#define		ATC_SRC_WIDTH_HALFWORD	(0x1 << 24)
110#define		ATC_SRC_WIDTH_WORD	(0x2 << 24)
111#define		ATC_REG_TO_SRC_WIDTH(r)	(((r) >> 24) & 0x3)
112#define	ATC_DST_WIDTH_MASK	(0x3 << 28)	/* Destination Single Transfer Size */
113#define		ATC_DST_WIDTH(x)	((x) << 28)
114#define		ATC_DST_WIDTH_BYTE	(0x0 << 28)
115#define		ATC_DST_WIDTH_HALFWORD	(0x1 << 28)
116#define		ATC_DST_WIDTH_WORD	(0x2 << 28)
117#define	ATC_DONE		(0x1 << 31)	/* Tx Done (only written back in descriptor) */
118
119/* Bitfields in CTRLB */
120#define	ATC_SIF(i)		(0x3 & (i))	/* Src tx done via AHB-Lite Interface i */
121#define	ATC_DIF(i)		((0x3 & (i)) <<  4)	/* Dst tx done via AHB-Lite Interface i */
122				  /* Specify AHB interfaces */
123#define AT_DMA_MEM_IF		0 /* interface 0 as memory interface */
124#define AT_DMA_PER_IF		1 /* interface 1 as peripheral interface */
125
126#define	ATC_SRC_PIP		(0x1 <<  8)	/* Source Picture-in-Picture enabled */
127#define	ATC_DST_PIP		(0x1 << 12)	/* Destination Picture-in-Picture enabled */
128#define	ATC_SRC_DSCR_DIS	(0x1 << 16)	/* Src Descriptor fetch disable */
129#define	ATC_DST_DSCR_DIS	(0x1 << 20)	/* Dst Descriptor fetch disable */
130#define	ATC_FC_MASK		(0x7 << 21)	/* Choose Flow Controller */
131#define		ATC_FC_MEM2MEM		(0x0 << 21)	/* Mem-to-Mem (DMA) */
132#define		ATC_FC_MEM2PER		(0x1 << 21)	/* Mem-to-Periph (DMA) */
133#define		ATC_FC_PER2MEM		(0x2 << 21)	/* Periph-to-Mem (DMA) */
134#define		ATC_FC_PER2PER		(0x3 << 21)	/* Periph-to-Periph (DMA) */
135#define		ATC_FC_PER2MEM_PER	(0x4 << 21)	/* Periph-to-Mem (Peripheral) */
136#define		ATC_FC_MEM2PER_PER	(0x5 << 21)	/* Mem-to-Periph (Peripheral) */
137#define		ATC_FC_PER2PER_SRCPER	(0x6 << 21)	/* Periph-to-Periph (Src Peripheral) */
138#define		ATC_FC_PER2PER_DSTPER	(0x7 << 21)	/* Periph-to-Periph (Dst Peripheral) */
139#define	ATC_SRC_ADDR_MODE_MASK	(0x3 << 24)
140#define		ATC_SRC_ADDR_MODE_INCR	(0x0 << 24)	/* Incrementing Mode */
141#define		ATC_SRC_ADDR_MODE_DECR	(0x1 << 24)	/* Decrementing Mode */
142#define		ATC_SRC_ADDR_MODE_FIXED	(0x2 << 24)	/* Fixed Mode */
143#define	ATC_DST_ADDR_MODE_MASK	(0x3 << 28)
144#define		ATC_DST_ADDR_MODE_INCR	(0x0 << 28)	/* Incrementing Mode */
145#define		ATC_DST_ADDR_MODE_DECR	(0x1 << 28)	/* Decrementing Mode */
146#define		ATC_DST_ADDR_MODE_FIXED	(0x2 << 28)	/* Fixed Mode */
147#define	ATC_IEN			(0x1 << 30)	/* BTC interrupt enable (active low) */
148#define	ATC_AUTO		(0x1 << 31)	/* Auto multiple buffer tx enable */
149
150/* Bitfields in CFG */
151/* are in at_hdmac.h */
152
153/* Bitfields in SPIP */
154#define	ATC_SPIP_HOLE(x)	(0xFFFFU & (x))
155#define	ATC_SPIP_BOUNDARY(x)	((0x3FF & (x)) << 16)
156
157/* Bitfields in DPIP */
158#define	ATC_DPIP_HOLE(x)	(0xFFFFU & (x))
159#define	ATC_DPIP_BOUNDARY(x)	((0x3FF & (x)) << 16)
160
161
162/*--  descriptors  -----------------------------------------------------*/
163
164/* LLI == Linked List Item; aka DMA buffer descriptor */
165struct at_lli {
166	/* values that are not changed by hardware */
167	u32 saddr;
168	u32 daddr;
169	/* value that may get written back: */
170	u32 ctrla;
171	/* more values that are not changed by hardware */
172	u32 ctrlb;
173	u32 dscr;	/* chain to next lli */
174};
175
176/**
177 * struct at_desc - software descriptor
178 * @at_lli: hardware lli structure
179 * @txd: support for the async_tx api
180 * @desc_node: node on the channed descriptors list
181 * @len: descriptor byte count
182 * @total_len: total transaction byte count
183 */
184struct at_desc {
185	/* FIRST values the hardware uses */
186	struct at_lli			lli;
187
188	/* THEN values for driver housekeeping */
189	struct list_head		tx_list;
190	struct dma_async_tx_descriptor	txd;
191	struct list_head		desc_node;
192	size_t				len;
193	size_t				total_len;
194
195	/* Interleaved data */
196	size_t				boundary;
197	size_t				dst_hole;
198	size_t				src_hole;
199
200	/* Memset temporary buffer */
201	bool				memset_buffer;
202	dma_addr_t			memset_paddr;
203	int				*memset_vaddr;
204};
205
206static inline struct at_desc *
207txd_to_at_desc(struct dma_async_tx_descriptor *txd)
208{
209	return container_of(txd, struct at_desc, txd);
210}
211
212
213/*--  Channels  --------------------------------------------------------*/
214
215/**
216 * atc_status - information bits stored in channel status flag
217 *
218 * Manipulated with atomic operations.
219 */
220enum atc_status {
221	ATC_IS_ERROR = 0,
222	ATC_IS_PAUSED = 1,
223	ATC_IS_CYCLIC = 24,
224};
225
226/**
227 * struct at_dma_chan - internal representation of an Atmel HDMAC channel
228 * @chan_common: common dmaengine channel object members
229 * @device: parent device
230 * @ch_regs: memory mapped register base
231 * @mask: channel index in a mask
232 * @per_if: peripheral interface
233 * @mem_if: memory interface
234 * @status: transmit status information from irq/prep* functions
235 *                to tasklet (use atomic operations)
236 * @tasklet: bottom half to finish transaction work
237 * @save_cfg: configuration register that is saved on suspend/resume cycle
238 * @save_dscr: for cyclic operations, preserve next descriptor address in
239 *             the cyclic list on suspend/resume cycle
240 * @dma_sconfig: configuration for slave transfers, passed via
241 * .device_config
242 * @lock: serializes enqueue/dequeue operations to descriptors lists
243 * @active_list: list of descriptors dmaengine is being running on
244 * @queue: list of descriptors ready to be submitted to engine
245 * @free_list: list of descriptors usable by the channel
246 */
247struct at_dma_chan {
248	struct dma_chan		chan_common;
249	struct at_dma		*device;
250	void __iomem		*ch_regs;
251	u8			mask;
252	u8			per_if;
253	u8			mem_if;
254	unsigned long		status;
255	struct tasklet_struct	tasklet;
256	u32			save_cfg;
257	u32			save_dscr;
258	struct dma_slave_config dma_sconfig;
259
260	spinlock_t		lock;
261
262	/* these other elements are all protected by lock */
263	struct list_head	active_list;
264	struct list_head	queue;
265	struct list_head	free_list;
266};
267
268#define	channel_readl(atchan, name) \
269	__raw_readl((atchan)->ch_regs + ATC_##name##_OFFSET)
270
271#define	channel_writel(atchan, name, val) \
272	__raw_writel((val), (atchan)->ch_regs + ATC_##name##_OFFSET)
273
274static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan)
275{
276	return container_of(dchan, struct at_dma_chan, chan_common);
277}
278
279/*
280 * Fix sconfig's burst size according to at_hdmac. We need to convert them as:
281 * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7.
282 *
283 * This can be done by finding most significant bit set.
284 */
285static inline void convert_burst(u32 *maxburst)
286{
287	if (*maxburst > 1)
288		*maxburst = fls(*maxburst) - 2;
289	else
290		*maxburst = 0;
291}
292
293/*
294 * Fix sconfig's bus width according to at_hdmac.
295 * 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2.
296 */
297static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width)
298{
299	switch (addr_width) {
300	case DMA_SLAVE_BUSWIDTH_2_BYTES:
301		return 1;
302	case DMA_SLAVE_BUSWIDTH_4_BYTES:
303		return 2;
304	default:
305		/* For 1 byte width or fallback */
306		return 0;
307	}
308}
309
310/*--  Controller  ------------------------------------------------------*/
311
312/**
313 * struct at_dma - internal representation of an Atmel HDMA Controller
314 * @chan_common: common dmaengine dma_device object members
315 * @atdma_devtype: identifier of DMA controller compatibility
316 * @ch_regs: memory mapped register base
317 * @clk: dma controller clock
318 * @save_imr: interrupt mask register that is saved on suspend/resume cycle
319 * @all_chan_mask: all channels availlable in a mask
320 * @dma_desc_pool: base of DMA descriptor region (DMA address)
321 * @chan: channels table to store at_dma_chan structures
322 */
323struct at_dma {
324	struct dma_device	dma_common;
325	void __iomem		*regs;
326	struct clk		*clk;
327	u32			save_imr;
328
329	u8			all_chan_mask;
330
331	struct dma_pool		*dma_desc_pool;
332	struct dma_pool		*memset_pool;
333	/* AT THE END channels table */
334	struct at_dma_chan	chan[];
335};
336
337#define	dma_readl(atdma, name) \
338	__raw_readl((atdma)->regs + AT_DMA_##name)
339#define	dma_writel(atdma, name, val) \
340	__raw_writel((val), (atdma)->regs + AT_DMA_##name)
341
342static inline struct at_dma *to_at_dma(struct dma_device *ddev)
343{
344	return container_of(ddev, struct at_dma, dma_common);
345}
346
347
348/*--  Helper functions  ------------------------------------------------*/
349
350static struct device *chan2dev(struct dma_chan *chan)
351{
352	return &chan->dev->device;
353}
354
355#if defined(VERBOSE_DEBUG)
356static void vdbg_dump_regs(struct at_dma_chan *atchan)
357{
358	struct at_dma	*atdma = to_at_dma(atchan->chan_common.device);
359
360	dev_err(chan2dev(&atchan->chan_common),
361		"  channel %d : imr = 0x%x, chsr = 0x%x\n",
362		atchan->chan_common.chan_id,
363		dma_readl(atdma, EBCIMR),
364		dma_readl(atdma, CHSR));
365
366	dev_err(chan2dev(&atchan->chan_common),
367		"  channel: s0x%x d0x%x ctrl0x%x:0x%x cfg0x%x l0x%x\n",
368		channel_readl(atchan, SADDR),
369		channel_readl(atchan, DADDR),
370		channel_readl(atchan, CTRLA),
371		channel_readl(atchan, CTRLB),
372		channel_readl(atchan, CFG),
373		channel_readl(atchan, DSCR));
374}
375#else
376static void vdbg_dump_regs(struct at_dma_chan *atchan) {}
377#endif
378
379static void atc_dump_lli(struct at_dma_chan *atchan, struct at_lli *lli)
380{
381	dev_crit(chan2dev(&atchan->chan_common),
382		 "desc: s%pad d%pad ctrl0x%x:0x%x l%pad\n",
383		 &lli->saddr, &lli->daddr,
384		 lli->ctrla, lli->ctrlb, &lli->dscr);
385}
386
387
388static void atc_setup_irq(struct at_dma *atdma, int chan_id, int on)
389{
390	u32 ebci;
391
392	/* enable interrupts on buffer transfer completion & error */
393	ebci =    AT_DMA_BTC(chan_id)
394		| AT_DMA_ERR(chan_id);
395	if (on)
396		dma_writel(atdma, EBCIER, ebci);
397	else
398		dma_writel(atdma, EBCIDR, ebci);
399}
400
401static void atc_enable_chan_irq(struct at_dma *atdma, int chan_id)
402{
403	atc_setup_irq(atdma, chan_id, 1);
404}
405
406static void atc_disable_chan_irq(struct at_dma *atdma, int chan_id)
407{
408	atc_setup_irq(atdma, chan_id, 0);
409}
410
411
412/**
413 * atc_chan_is_enabled - test if given channel is enabled
414 * @atchan: channel we want to test status
415 */
416static inline int atc_chan_is_enabled(struct at_dma_chan *atchan)
417{
418	struct at_dma	*atdma = to_at_dma(atchan->chan_common.device);
419
420	return !!(dma_readl(atdma, CHSR) & atchan->mask);
421}
422
423/**
424 * atc_chan_is_paused - test channel pause/resume status
425 * @atchan: channel we want to test status
426 */
427static inline int atc_chan_is_paused(struct at_dma_chan *atchan)
428{
429	return test_bit(ATC_IS_PAUSED, &atchan->status);
430}
431
432/**
433 * atc_chan_is_cyclic - test if given channel has cyclic property set
434 * @atchan: channel we want to test status
435 */
436static inline int atc_chan_is_cyclic(struct at_dma_chan *atchan)
437{
438	return test_bit(ATC_IS_CYCLIC, &atchan->status);
439}
440
441/**
442 * set_desc_eol - set end-of-link to descriptor so it will end transfer
443 * @desc: descriptor, signle or at the end of a chain, to end chain on
444 */
445static void set_desc_eol(struct at_desc *desc)
446{
447	u32 ctrlb = desc->lli.ctrlb;
448
449	ctrlb &= ~ATC_IEN;
450	ctrlb |= ATC_SRC_DSCR_DIS | ATC_DST_DSCR_DIS;
451
452	desc->lli.ctrlb = ctrlb;
453	desc->lli.dscr = 0;
454}
455
456#endif /* AT_HDMAC_REGS_H */
457