xref: /openbmc/linux/arch/m68k/include/asm/dma.h (revision 293d5b43)
1 #ifndef _M68K_DMA_H
2 #define _M68K_DMA_H 1
3 
4 #ifdef CONFIG_COLDFIRE
5 /*
6  * ColdFire DMA Model:
7  *   ColdFire DMA supports two forms of DMA: Single and Dual address. Single
8  * address mode emits a source address, and expects that the device will either
9  * pick up the data (DMA READ) or source data (DMA WRITE). This implies that
10  * the device will place data on the correct byte(s) of the data bus, as the
11  * memory transactions are always 32 bits. This implies that only 32 bit
12  * devices will find single mode transfers useful. Dual address DMA mode
13  * performs two cycles: source read and destination write. ColdFire will
14  * align the data so that the device will always get the correct bytes, thus
15  * is useful for 8 and 16 bit devices. This is the mode that is supported
16  * below.
17  *
18  * AUG/22/2000 : added support for 32-bit Dual-Address-Mode (K) 2000
19  *               Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
20  *
21  * AUG/25/2000 : added support for 8, 16 and 32-bit Single-Address-Mode (K)2000
22  *               Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
23  *
24  * APR/18/2002 : added proper support for MCF5272 DMA controller.
25  *               Arthur Shipkowski (art@videon-central.com)
26  */
27 
28 #include <asm/coldfire.h>
29 #include <asm/mcfsim.h>
30 #include <asm/mcfdma.h>
31 
32 /*
33  * Set number of channels of DMA on ColdFire for different implementations.
34  */
35 #if defined(CONFIG_M5249) || defined(CONFIG_M5307) || defined(CONFIG_M5407) || \
36 	defined(CONFIG_M523x) || defined(CONFIG_M527x) || \
37 	defined(CONFIG_M528x) || defined(CONFIG_M525x)
38 
39 #define MAX_M68K_DMA_CHANNELS 4
40 #elif defined(CONFIG_M5272)
41 #define MAX_M68K_DMA_CHANNELS 1
42 #elif defined(CONFIG_M53xx)
43 #define MAX_M68K_DMA_CHANNELS 0
44 #else
45 #define MAX_M68K_DMA_CHANNELS 2
46 #endif
47 
48 extern unsigned int dma_base_addr[MAX_M68K_DMA_CHANNELS];
49 extern unsigned int dma_device_address[MAX_M68K_DMA_CHANNELS];
50 
51 #if !defined(CONFIG_M5272)
52 #define DMA_MODE_WRITE_BIT  0x01  /* Memory/IO to IO/Memory select */
53 #define DMA_MODE_WORD_BIT   0x02  /* 8 or 16 bit transfers */
54 #define DMA_MODE_LONG_BIT   0x04  /* or 32 bit transfers */
55 #define DMA_MODE_SINGLE_BIT 0x08  /* single-address-mode */
56 
57 /* I/O to memory, 8 bits, mode */
58 #define DMA_MODE_READ	            0
59 /* memory to I/O, 8 bits, mode */
60 #define DMA_MODE_WRITE	            1
61 /* I/O to memory, 16 bits, mode */
62 #define DMA_MODE_READ_WORD          2
63 /* memory to I/O, 16 bits, mode */
64 #define DMA_MODE_WRITE_WORD         3
65 /* I/O to memory, 32 bits, mode */
66 #define DMA_MODE_READ_LONG          4
67 /* memory to I/O, 32 bits, mode */
68 #define DMA_MODE_WRITE_LONG         5
69 /* I/O to memory, 8 bits, single-address-mode */
70 #define DMA_MODE_READ_SINGLE        8
71 /* memory to I/O, 8 bits, single-address-mode */
72 #define DMA_MODE_WRITE_SINGLE       9
73 /* I/O to memory, 16 bits, single-address-mode */
74 #define DMA_MODE_READ_WORD_SINGLE  10
75 /* memory to I/O, 16 bits, single-address-mode */
76 #define DMA_MODE_WRITE_WORD_SINGLE 11
77 /* I/O to memory, 32 bits, single-address-mode */
78 #define DMA_MODE_READ_LONG_SINGLE  12
79 /* memory to I/O, 32 bits, single-address-mode */
80 #define DMA_MODE_WRITE_LONG_SINGLE 13
81 
82 #else /* CONFIG_M5272 is defined */
83 
84 /* Source static-address mode */
85 #define DMA_MODE_SRC_SA_BIT 0x01
86 /* Two bits to select between all four modes */
87 #define DMA_MODE_SSIZE_MASK 0x06
88 /* Offset to shift bits in */
89 #define DMA_MODE_SSIZE_OFF  0x01
90 /* Destination static-address mode */
91 #define DMA_MODE_DES_SA_BIT 0x10
92 /* Two bits to select between all four modes */
93 #define DMA_MODE_DSIZE_MASK 0x60
94 /* Offset to shift bits in */
95 #define DMA_MODE_DSIZE_OFF  0x05
96 /* Size modifiers */
97 #define DMA_MODE_SIZE_LONG  0x00
98 #define DMA_MODE_SIZE_BYTE  0x01
99 #define DMA_MODE_SIZE_WORD  0x02
100 #define DMA_MODE_SIZE_LINE  0x03
101 
102 /*
103  * Aliases to help speed quick ports; these may be suboptimal, however. They
104  * do not include the SINGLE mode modifiers since the MCF5272 does not have a
105  * mode where the device is in control of its addressing.
106  */
107 
108 /* I/O to memory, 8 bits, mode */
109 #define DMA_MODE_READ	              ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
110 /* memory to I/O, 8 bits, mode */
111 #define DMA_MODE_WRITE	            ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
112 /* I/O to memory, 16 bits, mode */
113 #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)
114 /* memory to I/O, 16 bits, mode */
115 #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)
116 /* I/O to memory, 32 bits, mode */
117 #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)
118 /* memory to I/O, 32 bits, mode */
119 #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)
120 
121 #endif /* !defined(CONFIG_M5272) */
122 
123 #if !defined(CONFIG_M5272)
124 /* enable/disable a specific DMA channel */
125 static __inline__ void enable_dma(unsigned int dmanr)
126 {
127   volatile unsigned short *dmawp;
128 
129 #ifdef DMA_DEBUG
130   printk("enable_dma(dmanr=%d)\n", dmanr);
131 #endif
132 
133   dmawp = (unsigned short *) dma_base_addr[dmanr];
134   dmawp[MCFDMA_DCR] |= MCFDMA_DCR_EEXT;
135 }
136 
137 static __inline__ void disable_dma(unsigned int dmanr)
138 {
139   volatile unsigned short *dmawp;
140   volatile unsigned char  *dmapb;
141 
142 #ifdef DMA_DEBUG
143   printk("disable_dma(dmanr=%d)\n", dmanr);
144 #endif
145 
146   dmawp = (unsigned short *) dma_base_addr[dmanr];
147   dmapb = (unsigned char *) dma_base_addr[dmanr];
148 
149   /* Turn off external requests, and stop any DMA in progress */
150   dmawp[MCFDMA_DCR] &= ~MCFDMA_DCR_EEXT;
151   dmapb[MCFDMA_DSR] = MCFDMA_DSR_DONE;
152 }
153 
154 /*
155  * Clear the 'DMA Pointer Flip Flop'.
156  * Write 0 for LSB/MSB, 1 for MSB/LSB access.
157  * Use this once to initialize the FF to a known state.
158  * After that, keep track of it. :-)
159  * --- In order to do that, the DMA routines below should ---
160  * --- only be used while interrupts are disabled! ---
161  *
162  * This is a NOP for ColdFire. Provide a stub for compatibility.
163  */
164 static __inline__ void clear_dma_ff(unsigned int dmanr)
165 {
166 }
167 
168 /* set mode (above) for a specific DMA channel */
169 static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
170 {
171 
172   volatile unsigned char  *dmabp;
173   volatile unsigned short *dmawp;
174 
175 #ifdef DMA_DEBUG
176   printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr, mode);
177 #endif
178 
179   dmabp = (unsigned char *) dma_base_addr[dmanr];
180   dmawp = (unsigned short *) dma_base_addr[dmanr];
181 
182   /* Clear config errors */
183   dmabp[MCFDMA_DSR] = MCFDMA_DSR_DONE;
184 
185   /* Set command register */
186   dmawp[MCFDMA_DCR] =
187     MCFDMA_DCR_INT |         /* Enable completion irq */
188     MCFDMA_DCR_CS |          /* Force one xfer per request */
189     MCFDMA_DCR_AA |          /* Enable auto alignment */
190     /* single-address-mode */
191     ((mode & DMA_MODE_SINGLE_BIT) ? MCFDMA_DCR_SAA : 0) |
192     /* sets s_rw (-> r/w) high if Memory to I/0 */
193     ((mode & DMA_MODE_WRITE_BIT) ? MCFDMA_DCR_S_RW : 0) |
194     /* Memory to I/O or I/O to Memory */
195     ((mode & DMA_MODE_WRITE_BIT) ? MCFDMA_DCR_SINC : MCFDMA_DCR_DINC) |
196     /* 32 bit, 16 bit or 8 bit transfers */
197     ((mode & DMA_MODE_WORD_BIT)  ? MCFDMA_DCR_SSIZE_WORD :
198      ((mode & DMA_MODE_LONG_BIT) ? MCFDMA_DCR_SSIZE_LONG :
199                                    MCFDMA_DCR_SSIZE_BYTE)) |
200     ((mode & DMA_MODE_WORD_BIT)  ? MCFDMA_DCR_DSIZE_WORD :
201      ((mode & DMA_MODE_LONG_BIT) ? MCFDMA_DCR_DSIZE_LONG :
202                                    MCFDMA_DCR_DSIZE_BYTE));
203 
204 #ifdef DEBUG_DMA
205   printk("%s(%d): dmanr=%d DSR[%x]=%x DCR[%x]=%x\n", __FILE__, __LINE__,
206          dmanr, (int) &dmabp[MCFDMA_DSR], dmabp[MCFDMA_DSR],
207 	 (int) &dmawp[MCFDMA_DCR], dmawp[MCFDMA_DCR]);
208 #endif
209 }
210 
211 /* Set transfer address for specific DMA channel */
212 static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
213 {
214   volatile unsigned short *dmawp;
215   volatile unsigned int   *dmalp;
216 
217 #ifdef DMA_DEBUG
218   printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr, a);
219 #endif
220 
221   dmawp = (unsigned short *) dma_base_addr[dmanr];
222   dmalp = (unsigned int *) dma_base_addr[dmanr];
223 
224   /* Determine which address registers are used for memory/device accesses */
225   if (dmawp[MCFDMA_DCR] & MCFDMA_DCR_SINC) {
226     /* Source incrementing, must be memory */
227     dmalp[MCFDMA_SAR] = a;
228     /* Set dest address, must be device */
229     dmalp[MCFDMA_DAR] = dma_device_address[dmanr];
230   } else {
231     /* Destination incrementing, must be memory */
232     dmalp[MCFDMA_DAR] = a;
233     /* Set source address, must be device */
234     dmalp[MCFDMA_SAR] = dma_device_address[dmanr];
235   }
236 
237 #ifdef DEBUG_DMA
238   printk("%s(%d): dmanr=%d DCR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
239 	__FILE__, __LINE__, dmanr, (int) &dmawp[MCFDMA_DCR], dmawp[MCFDMA_DCR],
240 	(int) &dmalp[MCFDMA_SAR], dmalp[MCFDMA_SAR],
241 	(int) &dmalp[MCFDMA_DAR], dmalp[MCFDMA_DAR]);
242 #endif
243 }
244 
245 /*
246  * Specific for Coldfire - sets device address.
247  * Should be called after the mode set call, and before set DMA address.
248  */
249 static __inline__ void set_dma_device_addr(unsigned int dmanr, unsigned int a)
250 {
251 #ifdef DMA_DEBUG
252   printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr, a);
253 #endif
254 
255   dma_device_address[dmanr] = a;
256 }
257 
258 /*
259  * NOTE 2: "count" represents _bytes_.
260  */
261 static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
262 {
263   volatile unsigned short *dmawp;
264 
265 #ifdef DMA_DEBUG
266   printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr, count);
267 #endif
268 
269   dmawp = (unsigned short *) dma_base_addr[dmanr];
270   dmawp[MCFDMA_BCR] = (unsigned short)count;
271 }
272 
273 /*
274  * Get DMA residue count. After a DMA transfer, this
275  * should return zero. Reading this while a DMA transfer is
276  * still in progress will return unpredictable results.
277  * Otherwise, it returns the number of _bytes_ left to transfer.
278  */
279 static __inline__ int get_dma_residue(unsigned int dmanr)
280 {
281   volatile unsigned short *dmawp;
282   unsigned short count;
283 
284 #ifdef DMA_DEBUG
285   printk("get_dma_residue(dmanr=%d)\n", dmanr);
286 #endif
287 
288   dmawp = (unsigned short *) dma_base_addr[dmanr];
289   count = dmawp[MCFDMA_BCR];
290   return((int) count);
291 }
292 #else /* CONFIG_M5272 is defined */
293 
294 /*
295  * The MCF5272 DMA controller is very different than the controller defined above
296  * in terms of register mapping.  For instance, with the exception of the 16-bit
297  * interrupt register (IRQ#85, for reference), all of the registers are 32-bit.
298  *
299  * The big difference, however, is the lack of device-requested DMA.  All modes
300  * are dual address transfer, and there is no 'device' setup or direction bit.
301  * You can DMA between a device and memory, between memory and memory, or even between
302  * two devices directly, with any combination of incrementing and non-incrementing
303  * addresses you choose.  This puts a crimp in distinguishing between the 'device
304  * address' set up by set_dma_device_addr.
305  *
306  * Therefore, there are two options.  One is to use set_dma_addr and set_dma_device_addr,
307  * which will act exactly as above in -- it will look to see if the source is set to
308  * autoincrement, and if so it will make the source use the set_dma_addr value and the
309  * destination the set_dma_device_addr value.  Otherwise the source will be set to the
310  * set_dma_device_addr value and the destination will get the set_dma_addr value.
311  *
312  * The other is to use the provided set_dma_src_addr and set_dma_dest_addr functions
313  * and make it explicit.  Depending on what you're doing, one of these two should work
314  * for you, but don't mix them in the same transfer setup.
315  */
316 
317 /* enable/disable a specific DMA channel */
318 static __inline__ void enable_dma(unsigned int dmanr)
319 {
320   volatile unsigned int  *dmalp;
321 
322 #ifdef DMA_DEBUG
323   printk("enable_dma(dmanr=%d)\n", dmanr);
324 #endif
325 
326   dmalp = (unsigned int *) dma_base_addr[dmanr];
327   dmalp[MCFDMA_DMR] |= MCFDMA_DMR_EN;
328 }
329 
330 static __inline__ void disable_dma(unsigned int dmanr)
331 {
332   volatile unsigned int   *dmalp;
333 
334 #ifdef DMA_DEBUG
335   printk("disable_dma(dmanr=%d)\n", dmanr);
336 #endif
337 
338   dmalp = (unsigned int *) dma_base_addr[dmanr];
339 
340   /* Turn off external requests, and stop any DMA in progress */
341   dmalp[MCFDMA_DMR] &= ~MCFDMA_DMR_EN;
342   dmalp[MCFDMA_DMR] |= MCFDMA_DMR_RESET;
343 }
344 
345 /*
346  * Clear the 'DMA Pointer Flip Flop'.
347  * Write 0 for LSB/MSB, 1 for MSB/LSB access.
348  * Use this once to initialize the FF to a known state.
349  * After that, keep track of it. :-)
350  * --- In order to do that, the DMA routines below should ---
351  * --- only be used while interrupts are disabled! ---
352  *
353  * This is a NOP for ColdFire. Provide a stub for compatibility.
354  */
355 static __inline__ void clear_dma_ff(unsigned int dmanr)
356 {
357 }
358 
359 /* set mode (above) for a specific DMA channel */
360 static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
361 {
362 
363   volatile unsigned int   *dmalp;
364   volatile unsigned short *dmawp;
365 
366 #ifdef DMA_DEBUG
367   printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr, mode);
368 #endif
369   dmalp = (unsigned int *) dma_base_addr[dmanr];
370   dmawp = (unsigned short *) dma_base_addr[dmanr];
371 
372   /* Clear config errors */
373   dmalp[MCFDMA_DMR] |= MCFDMA_DMR_RESET;
374 
375   /* Set command register */
376   dmalp[MCFDMA_DMR] =
377     MCFDMA_DMR_RQM_DUAL |         /* Mandatory Request Mode setting */
378     MCFDMA_DMR_DSTT_SD  |         /* Set up addressing types; set to supervisor-data. */
379     MCFDMA_DMR_SRCT_SD  |         /* Set up addressing types; set to supervisor-data. */
380     /* source static-address-mode */
381     ((mode & DMA_MODE_SRC_SA_BIT) ? MCFDMA_DMR_SRCM_SA : MCFDMA_DMR_SRCM_IA) |
382     /* dest static-address-mode */
383     ((mode & DMA_MODE_DES_SA_BIT) ? MCFDMA_DMR_DSTM_SA : MCFDMA_DMR_DSTM_IA) |
384     /* burst, 32 bit, 16 bit or 8 bit transfers are separately configurable on the MCF5272 */
385     (((mode & DMA_MODE_SSIZE_MASK) >> DMA_MODE_SSIZE_OFF) << MCFDMA_DMR_DSTS_OFF) |
386     (((mode & DMA_MODE_SSIZE_MASK) >> DMA_MODE_SSIZE_OFF) << MCFDMA_DMR_SRCS_OFF);
387 
388   dmawp[MCFDMA_DIR] |= MCFDMA_DIR_ASCEN;   /* Enable completion interrupts */
389 
390 #ifdef DEBUG_DMA
391   printk("%s(%d): dmanr=%d DMR[%x]=%x DIR[%x]=%x\n", __FILE__, __LINE__,
392          dmanr, (int) &dmalp[MCFDMA_DMR], dmabp[MCFDMA_DMR],
393 	 (int) &dmawp[MCFDMA_DIR], dmawp[MCFDMA_DIR]);
394 #endif
395 }
396 
397 /* Set transfer address for specific DMA channel */
398 static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
399 {
400   volatile unsigned int   *dmalp;
401 
402 #ifdef DMA_DEBUG
403   printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr, a);
404 #endif
405 
406   dmalp = (unsigned int *) dma_base_addr[dmanr];
407 
408   /* Determine which address registers are used for memory/device accesses */
409   if (dmalp[MCFDMA_DMR] & MCFDMA_DMR_SRCM) {
410     /* Source incrementing, must be memory */
411     dmalp[MCFDMA_DSAR] = a;
412     /* Set dest address, must be device */
413     dmalp[MCFDMA_DDAR] = dma_device_address[dmanr];
414   } else {
415     /* Destination incrementing, must be memory */
416     dmalp[MCFDMA_DDAR] = a;
417     /* Set source address, must be device */
418     dmalp[MCFDMA_DSAR] = dma_device_address[dmanr];
419   }
420 
421 #ifdef DEBUG_DMA
422   printk("%s(%d): dmanr=%d DMR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
423 	__FILE__, __LINE__, dmanr, (int) &dmawp[MCFDMA_DMR], dmawp[MCFDMA_DMR],
424 	(int) &dmalp[MCFDMA_DSAR], dmalp[MCFDMA_DSAR],
425 	(int) &dmalp[MCFDMA_DDAR], dmalp[MCFDMA_DDAR]);
426 #endif
427 }
428 
429 /*
430  * Specific for Coldfire - sets device address.
431  * Should be called after the mode set call, and before set DMA address.
432  */
433 static __inline__ void set_dma_device_addr(unsigned int dmanr, unsigned int a)
434 {
435 #ifdef DMA_DEBUG
436   printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr, a);
437 #endif
438 
439   dma_device_address[dmanr] = a;
440 }
441 
442 /*
443  * NOTE 2: "count" represents _bytes_.
444  *
445  * NOTE 3: While a 32-bit register, "count" is only a maximum 24-bit value.
446  */
447 static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
448 {
449   volatile unsigned int *dmalp;
450 
451 #ifdef DMA_DEBUG
452   printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr, count);
453 #endif
454 
455   dmalp = (unsigned int *) dma_base_addr[dmanr];
456   dmalp[MCFDMA_DBCR] = count;
457 }
458 
459 /*
460  * Get DMA residue count. After a DMA transfer, this
461  * should return zero. Reading this while a DMA transfer is
462  * still in progress will return unpredictable results.
463  * Otherwise, it returns the number of _bytes_ left to transfer.
464  */
465 static __inline__ int get_dma_residue(unsigned int dmanr)
466 {
467   volatile unsigned int *dmalp;
468   unsigned int count;
469 
470 #ifdef DMA_DEBUG
471   printk("get_dma_residue(dmanr=%d)\n", dmanr);
472 #endif
473 
474   dmalp = (unsigned int *) dma_base_addr[dmanr];
475   count = dmalp[MCFDMA_DBCR];
476   return(count);
477 }
478 
479 #endif /* !defined(CONFIG_M5272) */
480 #endif /* CONFIG_COLDFIRE */
481 
482 /* it's useless on the m68k, but unfortunately needed by the new
483    bootmem allocator (but this should do it for this) */
484 #define MAX_DMA_ADDRESS PAGE_OFFSET
485 
486 #define MAX_DMA_CHANNELS 8
487 
488 extern int request_dma(unsigned int dmanr, const char * device_id);	/* reserve a DMA channel */
489 extern void free_dma(unsigned int dmanr);	/* release it again */
490 
491 #ifdef CONFIG_PCI
492 extern int isa_dma_bridge_buggy;
493 #else
494 #define isa_dma_bridge_buggy    (0)
495 #endif
496 
497 #endif /* _M68K_DMA_H */
498