xref: /linux/arch/mips/include/asm/mach-au1x00/au1000_dma.h (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  * BRIEF MODULE DESCRIPTION
3  *	Defines for using and allocating DMA channels on the Alchemy
4  *      Au1x00 MIPS processors.
5  *
6  * Copyright 2000, 2008 MontaVista Software Inc.
7  * Author: MontaVista Software, Inc. <source@mvista.com>
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  *
14  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
15  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
16  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
17  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
18  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
20  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
21  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
22  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  *  You should have received a copy of the  GNU General Public License along
26  *  with this program; if not, write  to the Free Software Foundation, Inc.,
27  *  675 Mass Ave, Cambridge, MA 02139, USA.
28  *
29  */
30 #ifndef __ASM_AU1000_DMA_H
31 #define __ASM_AU1000_DMA_H
32 
33 #include <linux/io.h>		/* need byte IO */
34 #include <linux/spinlock.h>	/* And spinlocks */
35 #include <linux/delay.h>
36 #include <asm/system.h>
37 
38 #define NUM_AU1000_DMA_CHANNELS	8
39 
40 /* DMA Channel Register Offsets */
41 #define DMA_MODE_SET		0x00000000
42 #define DMA_MODE_READ		DMA_MODE_SET
43 #define DMA_MODE_CLEAR		0x00000004
44 /* DMA Mode register bits follow */
45 #define DMA_DAH_MASK		(0x0f << 20)
46 #define DMA_DID_BIT		16
47 #define DMA_DID_MASK		(0x0f << DMA_DID_BIT)
48 #define DMA_DS			(1 << 15)
49 #define DMA_BE			(1 << 13)
50 #define DMA_DR			(1 << 12)
51 #define DMA_TS8 		(1 << 11)
52 #define DMA_DW_BIT		9
53 #define DMA_DW_MASK		(0x03 << DMA_DW_BIT)
54 #define DMA_DW8			(0 << DMA_DW_BIT)
55 #define DMA_DW16		(1 << DMA_DW_BIT)
56 #define DMA_DW32		(2 << DMA_DW_BIT)
57 #define DMA_NC			(1 << 8)
58 #define DMA_IE			(1 << 7)
59 #define DMA_HALT		(1 << 6)
60 #define DMA_GO			(1 << 5)
61 #define DMA_AB			(1 << 4)
62 #define DMA_D1			(1 << 3)
63 #define DMA_BE1 		(1 << 2)
64 #define DMA_D0			(1 << 1)
65 #define DMA_BE0 		(1 << 0)
66 
67 #define DMA_PERIPHERAL_ADDR	0x00000008
68 #define DMA_BUFFER0_START	0x0000000C
69 #define DMA_BUFFER1_START	0x00000014
70 #define DMA_BUFFER0_COUNT	0x00000010
71 #define DMA_BUFFER1_COUNT	0x00000018
72 #define DMA_BAH_BIT	16
73 #define DMA_BAH_MASK	(0x0f << DMA_BAH_BIT)
74 #define DMA_COUNT_BIT	0
75 #define DMA_COUNT_MASK	(0xffff << DMA_COUNT_BIT)
76 
77 /* DMA Device IDs follow */
78 enum {
79 	DMA_ID_UART0_TX = 0,
80 	DMA_ID_UART0_RX,
81 	DMA_ID_GP04,
82 	DMA_ID_GP05,
83 	DMA_ID_AC97C_TX,
84 	DMA_ID_AC97C_RX,
85 	DMA_ID_UART3_TX,
86 	DMA_ID_UART3_RX,
87 	DMA_ID_USBDEV_EP0_RX,
88 	DMA_ID_USBDEV_EP0_TX,
89 	DMA_ID_USBDEV_EP2_TX,
90 	DMA_ID_USBDEV_EP3_TX,
91 	DMA_ID_USBDEV_EP4_RX,
92 	DMA_ID_USBDEV_EP5_RX,
93 	DMA_ID_I2S_TX,
94 	DMA_ID_I2S_RX,
95 	DMA_NUM_DEV
96 };
97 
98 /* DMA Device ID's for 2nd bank (AU1100) follow */
99 enum {
100 	DMA_ID_SD0_TX = 0,
101 	DMA_ID_SD0_RX,
102 	DMA_ID_SD1_TX,
103 	DMA_ID_SD1_RX,
104 	DMA_NUM_DEV_BANK2
105 };
106 
107 struct dma_chan {
108 	int dev_id;		/* this channel is allocated if >= 0, */
109 				/* free otherwise */
110 	unsigned int io;
111 	const char *dev_str;
112 	int irq;
113 	void *irq_dev;
114 	unsigned int fifo_addr;
115 	unsigned int mode;
116 };
117 
118 /* These are in arch/mips/au1000/common/dma.c */
119 extern struct dma_chan au1000_dma_table[];
120 extern int request_au1000_dma(int dev_id,
121 			      const char *dev_str,
122 			      irq_handler_t irqhandler,
123 			      unsigned long irqflags,
124 			      void *irq_dev_id);
125 extern void free_au1000_dma(unsigned int dmanr);
126 extern int au1000_dma_read_proc(char *buf, char **start, off_t fpos,
127 				int length, int *eof, void *data);
128 extern void dump_au1000_dma_channel(unsigned int dmanr);
129 extern spinlock_t au1000_dma_spin_lock;
130 
131 static inline struct dma_chan *get_dma_chan(unsigned int dmanr)
132 {
133 	if (dmanr >= NUM_AU1000_DMA_CHANNELS ||
134 	    au1000_dma_table[dmanr].dev_id < 0)
135 		return NULL;
136 	return &au1000_dma_table[dmanr];
137 }
138 
139 static inline unsigned long claim_dma_lock(void)
140 {
141 	unsigned long flags;
142 
143 	spin_lock_irqsave(&au1000_dma_spin_lock, flags);
144 	return flags;
145 }
146 
147 static inline void release_dma_lock(unsigned long flags)
148 {
149 	spin_unlock_irqrestore(&au1000_dma_spin_lock, flags);
150 }
151 
152 /*
153  * Set the DMA buffer enable bits in the mode register.
154  */
155 static inline void enable_dma_buffer0(unsigned int dmanr)
156 {
157 	struct dma_chan *chan = get_dma_chan(dmanr);
158 
159 	if (!chan)
160 		return;
161 	au_writel(DMA_BE0, chan->io + DMA_MODE_SET);
162 }
163 
164 static inline void enable_dma_buffer1(unsigned int dmanr)
165 {
166 	struct dma_chan *chan = get_dma_chan(dmanr);
167 
168 	if (!chan)
169 		return;
170 	au_writel(DMA_BE1, chan->io + DMA_MODE_SET);
171 }
172 static inline void enable_dma_buffers(unsigned int dmanr)
173 {
174 	struct dma_chan *chan = get_dma_chan(dmanr);
175 
176 	if (!chan)
177 		return;
178 	au_writel(DMA_BE0 | DMA_BE1, chan->io + DMA_MODE_SET);
179 }
180 
181 static inline void start_dma(unsigned int dmanr)
182 {
183 	struct dma_chan *chan = get_dma_chan(dmanr);
184 
185 	if (!chan)
186 		return;
187 	au_writel(DMA_GO, chan->io + DMA_MODE_SET);
188 }
189 
190 #define DMA_HALT_POLL 0x5000
191 
192 static inline void halt_dma(unsigned int dmanr)
193 {
194 	struct dma_chan *chan = get_dma_chan(dmanr);
195 	int i;
196 
197 	if (!chan)
198 		return;
199 	au_writel(DMA_GO, chan->io + DMA_MODE_CLEAR);
200 
201 	/* Poll the halt bit */
202 	for (i = 0; i < DMA_HALT_POLL; i++)
203 		if (au_readl(chan->io + DMA_MODE_READ) & DMA_HALT)
204 			break;
205 	if (i == DMA_HALT_POLL)
206 		printk(KERN_INFO "halt_dma: HALT poll expired!\n");
207 }
208 
209 static inline void disable_dma(unsigned int dmanr)
210 {
211 	struct dma_chan *chan = get_dma_chan(dmanr);
212 
213 	if (!chan)
214 		return;
215 
216 	halt_dma(dmanr);
217 
218 	/* Now we can disable the buffers */
219 	au_writel(~DMA_GO, chan->io + DMA_MODE_CLEAR);
220 }
221 
222 static inline int dma_halted(unsigned int dmanr)
223 {
224 	struct dma_chan *chan = get_dma_chan(dmanr);
225 
226 	if (!chan)
227 		return 1;
228 	return (au_readl(chan->io + DMA_MODE_READ) & DMA_HALT) ? 1 : 0;
229 }
230 
231 /* Initialize a DMA channel. */
232 static inline void init_dma(unsigned int dmanr)
233 {
234 	struct dma_chan *chan = get_dma_chan(dmanr);
235 	u32 mode;
236 
237 	if (!chan)
238 		return;
239 
240 	disable_dma(dmanr);
241 
242 	/* Set device FIFO address */
243 	au_writel(CPHYSADDR(chan->fifo_addr), chan->io + DMA_PERIPHERAL_ADDR);
244 
245 	mode = chan->mode | (chan->dev_id << DMA_DID_BIT);
246 	if (chan->irq)
247 		mode |= DMA_IE;
248 
249 	au_writel(~mode, chan->io + DMA_MODE_CLEAR);
250 	au_writel(mode,  chan->io + DMA_MODE_SET);
251 }
252 
253 /*
254  * Set mode for a specific DMA channel
255  */
256 static inline void set_dma_mode(unsigned int dmanr, unsigned int mode)
257 {
258 	struct dma_chan *chan = get_dma_chan(dmanr);
259 
260 	if (!chan)
261 		return;
262 	/*
263 	 * set_dma_mode is only allowed to change endianess, direction,
264 	 * transfer size, device FIFO width, and coherency settings.
265 	 * Make sure anything else is masked off.
266 	 */
267 	mode &= (DMA_BE | DMA_DR | DMA_TS8 | DMA_DW_MASK | DMA_NC);
268 	chan->mode &= ~(DMA_BE | DMA_DR | DMA_TS8 | DMA_DW_MASK | DMA_NC);
269 	chan->mode |= mode;
270 }
271 
272 static inline unsigned int get_dma_mode(unsigned int dmanr)
273 {
274 	struct dma_chan *chan = get_dma_chan(dmanr);
275 
276 	if (!chan)
277 		return 0;
278 	return chan->mode;
279 }
280 
281 static inline int get_dma_active_buffer(unsigned int dmanr)
282 {
283 	struct dma_chan *chan = get_dma_chan(dmanr);
284 
285 	if (!chan)
286 		return -1;
287 	return (au_readl(chan->io + DMA_MODE_READ) & DMA_AB) ? 1 : 0;
288 }
289 
290 /*
291  * Set the device FIFO address for a specific DMA channel - only
292  * applicable to GPO4 and GPO5. All the other devices have fixed
293  * FIFO addresses.
294  */
295 static inline void set_dma_fifo_addr(unsigned int dmanr, unsigned int a)
296 {
297 	struct dma_chan *chan = get_dma_chan(dmanr);
298 
299 	if (!chan)
300 		return;
301 
302 	if (chan->mode & DMA_DS)	/* second bank of device IDs */
303 		return;
304 
305 	if (chan->dev_id != DMA_ID_GP04 && chan->dev_id != DMA_ID_GP05)
306 		return;
307 
308 	au_writel(CPHYSADDR(a), chan->io + DMA_PERIPHERAL_ADDR);
309 }
310 
311 /*
312  * Clear the DMA buffer done bits in the mode register.
313  */
314 static inline void clear_dma_done0(unsigned int dmanr)
315 {
316 	struct dma_chan *chan = get_dma_chan(dmanr);
317 
318 	if (!chan)
319 		return;
320 	au_writel(DMA_D0, chan->io + DMA_MODE_CLEAR);
321 }
322 
323 static inline void clear_dma_done1(unsigned int dmanr)
324 {
325 	struct dma_chan *chan = get_dma_chan(dmanr);
326 
327 	if (!chan)
328 		return;
329 	au_writel(DMA_D1, chan->io + DMA_MODE_CLEAR);
330 }
331 
332 /*
333  * This does nothing - not applicable to Au1000 DMA.
334  */
335 static inline void set_dma_page(unsigned int dmanr, char pagenr)
336 {
337 }
338 
339 /*
340  * Set Buffer 0 transfer address for specific DMA channel.
341  */
342 static inline void set_dma_addr0(unsigned int dmanr, unsigned int a)
343 {
344 	struct dma_chan *chan = get_dma_chan(dmanr);
345 
346 	if (!chan)
347 		return;
348 	au_writel(a, chan->io + DMA_BUFFER0_START);
349 }
350 
351 /*
352  * Set Buffer 1 transfer address for specific DMA channel.
353  */
354 static inline void set_dma_addr1(unsigned int dmanr, unsigned int a)
355 {
356 	struct dma_chan *chan = get_dma_chan(dmanr);
357 
358 	if (!chan)
359 		return;
360 	au_writel(a, chan->io + DMA_BUFFER1_START);
361 }
362 
363 
364 /*
365  * Set Buffer 0 transfer size (max 64k) for a specific DMA channel.
366  */
367 static inline void set_dma_count0(unsigned int dmanr, unsigned int count)
368 {
369 	struct dma_chan *chan = get_dma_chan(dmanr);
370 
371 	if (!chan)
372 		return;
373 	count &= DMA_COUNT_MASK;
374 	au_writel(count, chan->io + DMA_BUFFER0_COUNT);
375 }
376 
377 /*
378  * Set Buffer 1 transfer size (max 64k) for a specific DMA channel.
379  */
380 static inline void set_dma_count1(unsigned int dmanr, unsigned int count)
381 {
382 	struct dma_chan *chan = get_dma_chan(dmanr);
383 
384 	if (!chan)
385 		return;
386 	count &= DMA_COUNT_MASK;
387 	au_writel(count, chan->io + DMA_BUFFER1_COUNT);
388 }
389 
390 /*
391  * Set both buffer transfer sizes (max 64k) for a specific DMA channel.
392  */
393 static inline void set_dma_count(unsigned int dmanr, unsigned int count)
394 {
395 	struct dma_chan *chan = get_dma_chan(dmanr);
396 
397 	if (!chan)
398 		return;
399 	count &= DMA_COUNT_MASK;
400 	au_writel(count, chan->io + DMA_BUFFER0_COUNT);
401 	au_writel(count, chan->io + DMA_BUFFER1_COUNT);
402 }
403 
404 /*
405  * Returns which buffer has its done bit set in the mode register.
406  * Returns -1 if neither or both done bits set.
407  */
408 static inline unsigned int get_dma_buffer_done(unsigned int dmanr)
409 {
410 	struct dma_chan *chan = get_dma_chan(dmanr);
411 
412 	if (!chan)
413 		return 0;
414 	return au_readl(chan->io + DMA_MODE_READ) & (DMA_D0 | DMA_D1);
415 }
416 
417 
418 /*
419  * Returns the DMA channel's Buffer Done IRQ number.
420  */
421 static inline int get_dma_done_irq(unsigned int dmanr)
422 {
423 	struct dma_chan *chan = get_dma_chan(dmanr);
424 
425 	if (!chan)
426 		return -1;
427 	return chan->irq;
428 }
429 
430 /*
431  * Get DMA residue count. Returns the number of _bytes_ left to transfer.
432  */
433 static inline int get_dma_residue(unsigned int dmanr)
434 {
435 	int curBufCntReg, count;
436 	struct dma_chan *chan = get_dma_chan(dmanr);
437 
438 	if (!chan)
439 		return 0;
440 
441 	curBufCntReg = (au_readl(chan->io + DMA_MODE_READ) & DMA_AB) ?
442 	    DMA_BUFFER1_COUNT : DMA_BUFFER0_COUNT;
443 
444 	count = au_readl(chan->io + curBufCntReg) & DMA_COUNT_MASK;
445 
446 	if ((chan->mode & DMA_DW_MASK) == DMA_DW16)
447 		count <<= 1;
448 	else if ((chan->mode & DMA_DW_MASK) == DMA_DW32)
449 		count <<= 2;
450 
451 	return count;
452 }
453 
454 #endif /* __ASM_AU1000_DMA_H */
455