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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _M68K_DMA_H
3#define _M68K_DMA_H 1
4
5#ifdef CONFIG_COLDFIRE
6/*
7 * ColdFire DMA Model:
8 * ColdFire DMA supports two forms of DMA: Single and Dual address. Single
9 * address mode emits a source address, and expects that the device will either
10 * pick up the data (DMA READ) or source data (DMA WRITE). This implies that
11 * the device will place data on the correct byte(s) of the data bus, as the
12 * memory transactions are always 32 bits. This implies that only 32 bit
13 * devices will find single mode transfers useful. Dual address DMA mode
14 * performs two cycles: source read and destination write. ColdFire will
15 * align the data so that the device will always get the correct bytes, thus
16 * is useful for 8 and 16 bit devices. This is the mode that is supported
17 * below.
18 *
19 * AUG/22/2000 : added support for 32-bit Dual-Address-Mode (K) 2000
20 * Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
21 *
22 * AUG/25/2000 : added support for 8, 16 and 32-bit Single-Address-Mode (K)2000
23 * Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
24 *
25 * APR/18/2002 : added proper support for MCF5272 DMA controller.
26 * Arthur Shipkowski (art@videon-central.com)
27 */
28
29#include <asm/coldfire.h>
30#include <asm/mcfsim.h>
31#include <asm/mcfdma.h>
32
33/*
34 * Set number of channels of DMA on ColdFire for different implementations.
35 */
36#if defined(CONFIG_M5249) || defined(CONFIG_M5307) || defined(CONFIG_M5407) || \
37 defined(CONFIG_M523x) || defined(CONFIG_M527x) || \
38 defined(CONFIG_M528x) || defined(CONFIG_M525x)
39
40#define MAX_M68K_DMA_CHANNELS 4
41#elif defined(CONFIG_M5272)
42#define MAX_M68K_DMA_CHANNELS 1
43#elif defined(CONFIG_M53xx)
44#define MAX_M68K_DMA_CHANNELS 0
45#else
46#define MAX_M68K_DMA_CHANNELS 2
47#endif
48
49extern unsigned int dma_base_addr[MAX_M68K_DMA_CHANNELS];
50extern unsigned int dma_device_address[MAX_M68K_DMA_CHANNELS];
51
52#if !defined(CONFIG_M5272)
53#define DMA_MODE_WRITE_BIT 0x01 /* Memory/IO to IO/Memory select */
54#define DMA_MODE_WORD_BIT 0x02 /* 8 or 16 bit transfers */
55#define DMA_MODE_LONG_BIT 0x04 /* or 32 bit transfers */
56#define DMA_MODE_SINGLE_BIT 0x08 /* single-address-mode */
57
58/* I/O to memory, 8 bits, mode */
59#define DMA_MODE_READ 0
60/* memory to I/O, 8 bits, mode */
61#define DMA_MODE_WRITE 1
62/* I/O to memory, 16 bits, mode */
63#define DMA_MODE_READ_WORD 2
64/* memory to I/O, 16 bits, mode */
65#define DMA_MODE_WRITE_WORD 3
66/* I/O to memory, 32 bits, mode */
67#define DMA_MODE_READ_LONG 4
68/* memory to I/O, 32 bits, mode */
69#define DMA_MODE_WRITE_LONG 5
70/* I/O to memory, 8 bits, single-address-mode */
71#define DMA_MODE_READ_SINGLE 8
72/* memory to I/O, 8 bits, single-address-mode */
73#define DMA_MODE_WRITE_SINGLE 9
74/* I/O to memory, 16 bits, single-address-mode */
75#define DMA_MODE_READ_WORD_SINGLE 10
76/* memory to I/O, 16 bits, single-address-mode */
77#define DMA_MODE_WRITE_WORD_SINGLE 11
78/* I/O to memory, 32 bits, single-address-mode */
79#define DMA_MODE_READ_LONG_SINGLE 12
80/* memory to I/O, 32 bits, single-address-mode */
81#define DMA_MODE_WRITE_LONG_SINGLE 13
82
83#else /* CONFIG_M5272 is defined */
84
85/* Source static-address mode */
86#define DMA_MODE_SRC_SA_BIT 0x01
87/* Two bits to select between all four modes */
88#define DMA_MODE_SSIZE_MASK 0x06
89/* Offset to shift bits in */
90#define DMA_MODE_SSIZE_OFF 0x01
91/* Destination static-address mode */
92#define DMA_MODE_DES_SA_BIT 0x10
93/* Two bits to select between all four modes */
94#define DMA_MODE_DSIZE_MASK 0x60
95/* Offset to shift bits in */
96#define DMA_MODE_DSIZE_OFF 0x05
97/* Size modifiers */
98#define DMA_MODE_SIZE_LONG 0x00
99#define DMA_MODE_SIZE_BYTE 0x01
100#define DMA_MODE_SIZE_WORD 0x02
101#define DMA_MODE_SIZE_LINE 0x03
102
103/*
104 * Aliases to help speed quick ports; these may be suboptimal, however. They
105 * do not include the SINGLE mode modifiers since the MCF5272 does not have a
106 * mode where the device is in control of its addressing.
107 */
108
109/* I/O to memory, 8 bits, mode */
110#define DMA_MODE_READ ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
111/* memory to I/O, 8 bits, mode */
112#define DMA_MODE_WRITE ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
113/* I/O to memory, 16 bits, mode */
114#define DMA_MODE_READ_WORD ((DMA_MODE_SIZE_WORD << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_WORD << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
115/* memory to I/O, 16 bits, mode */
116#define DMA_MODE_WRITE_WORD ((DMA_MODE_SIZE_WORD << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_WORD << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
117/* I/O to memory, 32 bits, mode */
118#define DMA_MODE_READ_LONG ((DMA_MODE_SIZE_LONG << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_LONG << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
119/* memory to I/O, 32 bits, mode */
120#define DMA_MODE_WRITE_LONG ((DMA_MODE_SIZE_LONG << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_LONG << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
121
122#endif /* !defined(CONFIG_M5272) */
123
124#if !defined(CONFIG_M5272)
125/* enable/disable a specific DMA channel */
126static __inline__ void enable_dma(unsigned int dmanr)
127{
128 volatile unsigned short *dmawp;
129
130#ifdef DMA_DEBUG
131 printk("enable_dma(dmanr=%d)\n", dmanr);
132#endif
133
134 dmawp = (unsigned short *) dma_base_addr[dmanr];
135 dmawp[MCFDMA_DCR] |= MCFDMA_DCR_EEXT;
136}
137
138static __inline__ void disable_dma(unsigned int dmanr)
139{
140 volatile unsigned short *dmawp;
141 volatile unsigned char *dmapb;
142
143#ifdef DMA_DEBUG
144 printk("disable_dma(dmanr=%d)\n", dmanr);
145#endif
146
147 dmawp = (unsigned short *) dma_base_addr[dmanr];
148 dmapb = (unsigned char *) dma_base_addr[dmanr];
149
150 /* Turn off external requests, and stop any DMA in progress */
151 dmawp[MCFDMA_DCR] &= ~MCFDMA_DCR_EEXT;
152 dmapb[MCFDMA_DSR] = MCFDMA_DSR_DONE;
153}
154
155/*
156 * Clear the 'DMA Pointer Flip Flop'.
157 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
158 * Use this once to initialize the FF to a known state.
159 * After that, keep track of it. :-)
160 * --- In order to do that, the DMA routines below should ---
161 * --- only be used while interrupts are disabled! ---
162 *
163 * This is a NOP for ColdFire. Provide a stub for compatibility.
164 */
165static __inline__ void clear_dma_ff(unsigned int dmanr)
166{
167}
168
169/* set mode (above) for a specific DMA channel */
170static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
171{
172
173 volatile unsigned char *dmabp;
174 volatile unsigned short *dmawp;
175
176#ifdef DMA_DEBUG
177 printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr, mode);
178#endif
179
180 dmabp = (unsigned char *) dma_base_addr[dmanr];
181 dmawp = (unsigned short *) dma_base_addr[dmanr];
182
183 /* Clear config errors */
184 dmabp[MCFDMA_DSR] = MCFDMA_DSR_DONE;
185
186 /* Set command register */
187 dmawp[MCFDMA_DCR] =
188 MCFDMA_DCR_INT | /* Enable completion irq */
189 MCFDMA_DCR_CS | /* Force one xfer per request */
190 MCFDMA_DCR_AA | /* Enable auto alignment */
191 /* single-address-mode */
192 ((mode & DMA_MODE_SINGLE_BIT) ? MCFDMA_DCR_SAA : 0) |
193 /* sets s_rw (-> r/w) high if Memory to I/0 */
194 ((mode & DMA_MODE_WRITE_BIT) ? MCFDMA_DCR_S_RW : 0) |
195 /* Memory to I/O or I/O to Memory */
196 ((mode & DMA_MODE_WRITE_BIT) ? MCFDMA_DCR_SINC : MCFDMA_DCR_DINC) |
197 /* 32 bit, 16 bit or 8 bit transfers */
198 ((mode & DMA_MODE_WORD_BIT) ? MCFDMA_DCR_SSIZE_WORD :
199 ((mode & DMA_MODE_LONG_BIT) ? MCFDMA_DCR_SSIZE_LONG :
200 MCFDMA_DCR_SSIZE_BYTE)) |
201 ((mode & DMA_MODE_WORD_BIT) ? MCFDMA_DCR_DSIZE_WORD :
202 ((mode & DMA_MODE_LONG_BIT) ? MCFDMA_DCR_DSIZE_LONG :
203 MCFDMA_DCR_DSIZE_BYTE));
204
205#ifdef DEBUG_DMA
206 printk("%s(%d): dmanr=%d DSR[%x]=%x DCR[%x]=%x\n", __FILE__, __LINE__,
207 dmanr, (int) &dmabp[MCFDMA_DSR], dmabp[MCFDMA_DSR],
208 (int) &dmawp[MCFDMA_DCR], dmawp[MCFDMA_DCR]);
209#endif
210}
211
212/* Set transfer address for specific DMA channel */
213static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
214{
215 volatile unsigned short *dmawp;
216 volatile unsigned int *dmalp;
217
218#ifdef DMA_DEBUG
219 printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr, a);
220#endif
221
222 dmawp = (unsigned short *) dma_base_addr[dmanr];
223 dmalp = (unsigned int *) dma_base_addr[dmanr];
224
225 /* Determine which address registers are used for memory/device accesses */
226 if (dmawp[MCFDMA_DCR] & MCFDMA_DCR_SINC) {
227 /* Source incrementing, must be memory */
228 dmalp[MCFDMA_SAR] = a;
229 /* Set dest address, must be device */
230 dmalp[MCFDMA_DAR] = dma_device_address[dmanr];
231 } else {
232 /* Destination incrementing, must be memory */
233 dmalp[MCFDMA_DAR] = a;
234 /* Set source address, must be device */
235 dmalp[MCFDMA_SAR] = dma_device_address[dmanr];
236 }
237
238#ifdef DEBUG_DMA
239 printk("%s(%d): dmanr=%d DCR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
240 __FILE__, __LINE__, dmanr, (int) &dmawp[MCFDMA_DCR], dmawp[MCFDMA_DCR],
241 (int) &dmalp[MCFDMA_SAR], dmalp[MCFDMA_SAR],
242 (int) &dmalp[MCFDMA_DAR], dmalp[MCFDMA_DAR]);
243#endif
244}
245
246/*
247 * Specific for Coldfire - sets device address.
248 * Should be called after the mode set call, and before set DMA address.
249 */
250static __inline__ void set_dma_device_addr(unsigned int dmanr, unsigned int a)
251{
252#ifdef DMA_DEBUG
253 printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr, a);
254#endif
255
256 dma_device_address[dmanr] = a;
257}
258
259/*
260 * NOTE 2: "count" represents _bytes_.
261 */
262static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
263{
264 volatile unsigned short *dmawp;
265
266#ifdef DMA_DEBUG
267 printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr, count);
268#endif
269
270 dmawp = (unsigned short *) dma_base_addr[dmanr];
271 dmawp[MCFDMA_BCR] = (unsigned short)count;
272}
273
274/*
275 * Get DMA residue count. After a DMA transfer, this
276 * should return zero. Reading this while a DMA transfer is
277 * still in progress will return unpredictable results.
278 * Otherwise, it returns the number of _bytes_ left to transfer.
279 */
280static __inline__ int get_dma_residue(unsigned int dmanr)
281{
282 volatile unsigned short *dmawp;
283 unsigned short count;
284
285#ifdef DMA_DEBUG
286 printk("get_dma_residue(dmanr=%d)\n", dmanr);
287#endif
288
289 dmawp = (unsigned short *) dma_base_addr[dmanr];
290 count = dmawp[MCFDMA_BCR];
291 return((int) count);
292}
293#else /* CONFIG_M5272 is defined */
294
295/*
296 * The MCF5272 DMA controller is very different than the controller defined above
297 * in terms of register mapping. For instance, with the exception of the 16-bit
298 * interrupt register (IRQ#85, for reference), all of the registers are 32-bit.
299 *
300 * The big difference, however, is the lack of device-requested DMA. All modes
301 * are dual address transfer, and there is no 'device' setup or direction bit.
302 * You can DMA between a device and memory, between memory and memory, or even between
303 * two devices directly, with any combination of incrementing and non-incrementing
304 * addresses you choose. This puts a crimp in distinguishing between the 'device
305 * address' set up by set_dma_device_addr.
306 *
307 * Therefore, there are two options. One is to use set_dma_addr and set_dma_device_addr,
308 * which will act exactly as above in -- it will look to see if the source is set to
309 * autoincrement, and if so it will make the source use the set_dma_addr value and the
310 * destination the set_dma_device_addr value. Otherwise the source will be set to the
311 * set_dma_device_addr value and the destination will get the set_dma_addr value.
312 *
313 * The other is to use the provided set_dma_src_addr and set_dma_dest_addr functions
314 * and make it explicit. Depending on what you're doing, one of these two should work
315 * for you, but don't mix them in the same transfer setup.
316 */
317
318/* enable/disable a specific DMA channel */
319static __inline__ void enable_dma(unsigned int dmanr)
320{
321 volatile unsigned int *dmalp;
322
323#ifdef DMA_DEBUG
324 printk("enable_dma(dmanr=%d)\n", dmanr);
325#endif
326
327 dmalp = (unsigned int *) dma_base_addr[dmanr];
328 dmalp[MCFDMA_DMR] |= MCFDMA_DMR_EN;
329}
330
331static __inline__ void disable_dma(unsigned int dmanr)
332{
333 volatile unsigned int *dmalp;
334
335#ifdef DMA_DEBUG
336 printk("disable_dma(dmanr=%d)\n", dmanr);
337#endif
338
339 dmalp = (unsigned int *) dma_base_addr[dmanr];
340
341 /* Turn off external requests, and stop any DMA in progress */
342 dmalp[MCFDMA_DMR] &= ~MCFDMA_DMR_EN;
343 dmalp[MCFDMA_DMR] |= MCFDMA_DMR_RESET;
344}
345
346/*
347 * Clear the 'DMA Pointer Flip Flop'.
348 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
349 * Use this once to initialize the FF to a known state.
350 * After that, keep track of it. :-)
351 * --- In order to do that, the DMA routines below should ---
352 * --- only be used while interrupts are disabled! ---
353 *
354 * This is a NOP for ColdFire. Provide a stub for compatibility.
355 */
356static __inline__ void clear_dma_ff(unsigned int dmanr)
357{
358}
359
360/* set mode (above) for a specific DMA channel */
361static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
362{
363
364 volatile unsigned int *dmalp;
365 volatile unsigned short *dmawp;
366
367#ifdef DMA_DEBUG
368 printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr, mode);
369#endif
370 dmalp = (unsigned int *) dma_base_addr[dmanr];
371 dmawp = (unsigned short *) dma_base_addr[dmanr];
372
373 /* Clear config errors */
374 dmalp[MCFDMA_DMR] |= MCFDMA_DMR_RESET;
375
376 /* Set command register */
377 dmalp[MCFDMA_DMR] =
378 MCFDMA_DMR_RQM_DUAL | /* Mandatory Request Mode setting */
379 MCFDMA_DMR_DSTT_SD | /* Set up addressing types; set to supervisor-data. */
380 MCFDMA_DMR_SRCT_SD | /* Set up addressing types; set to supervisor-data. */
381 /* source static-address-mode */
382 ((mode & DMA_MODE_SRC_SA_BIT) ? MCFDMA_DMR_SRCM_SA : MCFDMA_DMR_SRCM_IA) |
383 /* dest static-address-mode */
384 ((mode & DMA_MODE_DES_SA_BIT) ? MCFDMA_DMR_DSTM_SA : MCFDMA_DMR_DSTM_IA) |
385 /* burst, 32 bit, 16 bit or 8 bit transfers are separately configurable on the MCF5272 */
386 (((mode & DMA_MODE_SSIZE_MASK) >> DMA_MODE_SSIZE_OFF) << MCFDMA_DMR_DSTS_OFF) |
387 (((mode & DMA_MODE_SSIZE_MASK) >> DMA_MODE_SSIZE_OFF) << MCFDMA_DMR_SRCS_OFF);
388
389 dmawp[MCFDMA_DIR] |= MCFDMA_DIR_ASCEN; /* Enable completion interrupts */
390
391#ifdef DEBUG_DMA
392 printk("%s(%d): dmanr=%d DMR[%x]=%x DIR[%x]=%x\n", __FILE__, __LINE__,
393 dmanr, (int) &dmalp[MCFDMA_DMR], dmalp[MCFDMA_DMR],
394 (int) &dmawp[MCFDMA_DIR], dmawp[MCFDMA_DIR]);
395#endif
396}
397
398/* Set transfer address for specific DMA channel */
399static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
400{
401 volatile unsigned int *dmalp;
402
403#ifdef DMA_DEBUG
404 printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr, a);
405#endif
406
407 dmalp = (unsigned int *) dma_base_addr[dmanr];
408
409 /* Determine which address registers are used for memory/device accesses */
410 if (dmalp[MCFDMA_DMR] & MCFDMA_DMR_SRCM) {
411 /* Source incrementing, must be memory */
412 dmalp[MCFDMA_DSAR] = a;
413 /* Set dest address, must be device */
414 dmalp[MCFDMA_DDAR] = dma_device_address[dmanr];
415 } else {
416 /* Destination incrementing, must be memory */
417 dmalp[MCFDMA_DDAR] = a;
418 /* Set source address, must be device */
419 dmalp[MCFDMA_DSAR] = dma_device_address[dmanr];
420 }
421
422#ifdef DEBUG_DMA
423 printk("%s(%d): dmanr=%d DMR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
424 __FILE__, __LINE__, dmanr, (int) &dmalp[MCFDMA_DMR], dmalp[MCFDMA_DMR],
425 (int) &dmalp[MCFDMA_DSAR], dmalp[MCFDMA_DSAR],
426 (int) &dmalp[MCFDMA_DDAR], dmalp[MCFDMA_DDAR]);
427#endif
428}
429
430/*
431 * Specific for Coldfire - sets device address.
432 * Should be called after the mode set call, and before set DMA address.
433 */
434static __inline__ void set_dma_device_addr(unsigned int dmanr, unsigned int a)
435{
436#ifdef DMA_DEBUG
437 printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr, a);
438#endif
439
440 dma_device_address[dmanr] = a;
441}
442
443/*
444 * NOTE 2: "count" represents _bytes_.
445 *
446 * NOTE 3: While a 32-bit register, "count" is only a maximum 24-bit value.
447 */
448static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
449{
450 volatile unsigned int *dmalp;
451
452#ifdef DMA_DEBUG
453 printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr, count);
454#endif
455
456 dmalp = (unsigned int *) dma_base_addr[dmanr];
457 dmalp[MCFDMA_DBCR] = count;
458}
459
460/*
461 * Get DMA residue count. After a DMA transfer, this
462 * should return zero. Reading this while a DMA transfer is
463 * still in progress will return unpredictable results.
464 * Otherwise, it returns the number of _bytes_ left to transfer.
465 */
466static __inline__ int get_dma_residue(unsigned int dmanr)
467{
468 volatile unsigned int *dmalp;
469 unsigned int count;
470
471#ifdef DMA_DEBUG
472 printk("get_dma_residue(dmanr=%d)\n", dmanr);
473#endif
474
475 dmalp = (unsigned int *) dma_base_addr[dmanr];
476 count = dmalp[MCFDMA_DBCR];
477 return(count);
478}
479
480#endif /* !defined(CONFIG_M5272) */
481#endif /* CONFIG_COLDFIRE */
482
483/* it's useless on the m68k, but unfortunately needed by the new
484 bootmem allocator (but this should do it for this) */
485#define MAX_DMA_ADDRESS PAGE_OFFSET
486
487#define MAX_DMA_CHANNELS 8
488
489extern int request_dma(unsigned int dmanr, const char * device_id); /* reserve a DMA channel */
490extern void free_dma(unsigned int dmanr); /* release it again */
491
492#ifdef CONFIG_PCI
493extern int isa_dma_bridge_buggy;
494#else
495#define isa_dma_bridge_buggy (0)
496#endif
497
498#endif /* _M68K_DMA_H */