10 * ColdFire DMA supports two forms of DMA: Single and Dual address. Single
11 * address mode emits a source address, and expects that the device will either
12 * pick up the data (DMA READ) or source data (DMA WRITE). This implies that
13 * the device will place data on the correct byte(s) of the data bus, as the
14 * memory transactions are always 32 bits. This implies that only 32 bit
15 * devices will find single mode transfers useful. Dual address DMA mode
16 * performs two cycles: source read and destination write. ColdFire will
17 * align the data so that the device will always get the correct bytes, thus
18 * is useful for 8 and 16 bit devices. This is the mode that is supported
21 * AUG/22/2000 : added support for 32-bit Dual-Address-Mode (K) 2000
22 * Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
24 * AUG/25/2000 : addad support for 8, 16 and 32-bit Single-Address-Mode (K)2000
25 * Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
27 * APR/18/2002 : added proper support for MCF5272 DMA controller.
28 * Arthur Shipkowski (art@videon-central.com)
31 #include <asm/coldfire.h>
32 #include <asm/mcfsim.h>
33 #include <asm/mcfdma.h>
36 * Set number of channels of DMA on ColdFire for different implementations.
38 #if defined(CONFIG_M5249) || defined(CONFIG_M5307) || defined(CONFIG_M5407)
39 #define MAX_M68K_DMA_CHANNELS 4
40 #elif defined(CONFIG_M5272)
41 #define MAX_M68K_DMA_CHANNELS 1
43 #define MAX_M68K_DMA_CHANNELS 2
46 extern unsigned int dma_base_addr
[MAX_M68K_DMA_CHANNELS
];
47 extern unsigned int dma_device_address
[MAX_M68K_DMA_CHANNELS
];
49 #if !defined(CONFIG_M5272)
50 #define DMA_MODE_WRITE_BIT 0x01 /* Memory/IO to IO/Memory select */
51 #define DMA_MODE_WORD_BIT 0x02 /* 8 or 16 bit transfers */
52 #define DMA_MODE_LONG_BIT 0x04 /* or 32 bit transfers */
53 #define DMA_MODE_SINGLE_BIT 0x08 /* single-address-mode */
55 /* I/O to memory, 8 bits, mode */
56 #define DMA_MODE_READ 0
57 /* memory to I/O, 8 bits, mode */
58 #define DMA_MODE_WRITE 1
59 /* I/O to memory, 16 bits, mode */
60 #define DMA_MODE_READ_WORD 2
61 /* memory to I/O, 16 bits, mode */
62 #define DMA_MODE_WRITE_WORD 3
63 /* I/O to memory, 32 bits, mode */
64 #define DMA_MODE_READ_LONG 4
65 /* memory to I/O, 32 bits, mode */
66 #define DMA_MODE_WRITE_LONG 5
67 /* I/O to memory, 8 bits, single-address-mode */
68 #define DMA_MODE_READ_SINGLE 8
69 /* memory to I/O, 8 bits, single-address-mode */
70 #define DMA_MODE_WRITE_SINGLE 9
71 /* I/O to memory, 16 bits, single-address-mode */
72 #define DMA_MODE_READ_WORD_SINGLE 10
73 /* memory to I/O, 16 bits, single-address-mode */
74 #define DMA_MODE_WRITE_WORD_SINGLE 11
75 /* I/O to memory, 32 bits, single-address-mode */
76 #define DMA_MODE_READ_LONG_SINGLE 12
77 /* memory to I/O, 32 bits, single-address-mode */
78 #define DMA_MODE_WRITE_LONG_SINGLE 13
80 #else /* CONFIG_M5272 is defined */
82 /* Source static-address mode */
83 #define DMA_MODE_SRC_SA_BIT 0x01
84 /* Two bits to select between all four modes */
85 #define DMA_MODE_SSIZE_MASK 0x06
86 /* Offset to shift bits in */
87 #define DMA_MODE_SSIZE_OFF 0x01
88 /* Destination static-address mode */
89 #define DMA_MODE_DES_SA_BIT 0x10
90 /* Two bits to select between all four modes */
91 #define DMA_MODE_DSIZE_MASK 0x60
92 /* Offset to shift bits in */
93 #define DMA_MODE_DSIZE_OFF 0x05
95 #define DMA_MODE_SIZE_LONG 0x00
96 #define DMA_MODE_SIZE_BYTE 0x01
97 #define DMA_MODE_SIZE_WORD 0x02
98 #define DMA_MODE_SIZE_LINE 0x03
101 * Aliases to help speed quick ports; these may be suboptimal, however. They
102 * do not include the SINGLE mode modifiers since the MCF5272 does not have a
103 * mode where the device is in control of its addressing.
106 /* I/O to memory, 8 bits, mode */
107 #define DMA_MODE_READ ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
108 /* memory to I/O, 8 bits, mode */
109 #define DMA_MODE_WRITE ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
110 /* I/O to memory, 16 bits, mode */
111 #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)
112 /* memory to I/O, 16 bits, mode */
113 #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)
114 /* I/O to memory, 32 bits, mode */
115 #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)
116 /* memory to I/O, 32 bits, mode */
117 #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)
119 #endif /* !defined(CONFIG_M5272) */
121 #if !defined(CONFIG_M5272)
122 /* enable/disable a specific DMA channel */
123 static __inline__
void enable_dma(unsigned int dmanr
)
125 volatile unsigned short *dmawp
;
128 printk("enable_dma(dmanr=%d)\n", dmanr
);
131 dmawp
= (unsigned short *) dma_base_addr
[dmanr
];
132 dmawp
[MCFDMA_DCR
] |= MCFDMA_DCR_EEXT
;
135 static __inline__
void disable_dma(unsigned int dmanr
)
137 volatile unsigned short *dmawp
;
138 volatile unsigned char *dmapb
;
141 printk("disable_dma(dmanr=%d)\n", dmanr
);
144 dmawp
= (unsigned short *) dma_base_addr
[dmanr
];
145 dmapb
= (unsigned char *) dma_base_addr
[dmanr
];
147 /* Turn off external requests, and stop any DMA in progress */
148 dmawp
[MCFDMA_DCR
] &= ~MCFDMA_DCR_EEXT
;
149 dmapb
[MCFDMA_DSR
] = MCFDMA_DSR_DONE
;
153 * Clear the 'DMA Pointer Flip Flop'.
154 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
155 * Use this once to initialize the FF to a known state.
156 * After that, keep track of it. :-)
157 * --- In order to do that, the DMA routines below should ---
158 * --- only be used while interrupts are disabled! ---
160 * This is a NOP for ColdFire. Provide a stub for compatibility.
162 static __inline__
void clear_dma_ff(unsigned int dmanr
)
166 /* set mode (above) for a specific DMA channel */
167 static __inline__
void set_dma_mode(unsigned int dmanr
, char mode
)
170 volatile unsigned char *dmabp
;
171 volatile unsigned short *dmawp
;
174 printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr
, mode
);
177 dmabp
= (unsigned char *) dma_base_addr
[dmanr
];
178 dmawp
= (unsigned short *) dma_base_addr
[dmanr
];
180 // Clear config errors
181 dmabp
[MCFDMA_DSR
] = MCFDMA_DSR_DONE
;
183 // Set command register
185 MCFDMA_DCR_INT
| // Enable completion irq
186 MCFDMA_DCR_CS
| // Force one xfer per request
187 MCFDMA_DCR_AA
| // Enable auto alignment
188 // single-address-mode
189 ((mode
& DMA_MODE_SINGLE_BIT
) ? MCFDMA_DCR_SAA
: 0) |
190 // sets s_rw (-> r/w) high if Memory to I/0
191 ((mode
& DMA_MODE_WRITE_BIT
) ? MCFDMA_DCR_S_RW
: 0) |
192 // Memory to I/O or I/O to Memory
193 ((mode
& DMA_MODE_WRITE_BIT
) ? MCFDMA_DCR_SINC
: MCFDMA_DCR_DINC
) |
194 // 32 bit, 16 bit or 8 bit transfers
195 ((mode
& DMA_MODE_WORD_BIT
) ? MCFDMA_DCR_SSIZE_WORD
:
196 ((mode
& DMA_MODE_LONG_BIT
) ? MCFDMA_DCR_SSIZE_LONG
:
197 MCFDMA_DCR_SSIZE_BYTE
)) |
198 ((mode
& DMA_MODE_WORD_BIT
) ? MCFDMA_DCR_DSIZE_WORD
:
199 ((mode
& DMA_MODE_LONG_BIT
) ? MCFDMA_DCR_DSIZE_LONG
:
200 MCFDMA_DCR_DSIZE_BYTE
));
203 printk("%s(%d): dmanr=%d DSR[%x]=%x DCR[%x]=%x\n", __FILE__
, __LINE__
,
204 dmanr
, (int) &dmabp
[MCFDMA_DSR
], dmabp
[MCFDMA_DSR
],
205 (int) &dmawp
[MCFDMA_DCR
], dmawp
[MCFDMA_DCR
]);
209 /* Set transfer address for specific DMA channel */
210 static __inline__
void set_dma_addr(unsigned int dmanr
, unsigned int a
)
212 volatile unsigned short *dmawp
;
213 volatile unsigned int *dmalp
;
216 printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr
, a
);
219 dmawp
= (unsigned short *) dma_base_addr
[dmanr
];
220 dmalp
= (unsigned int *) dma_base_addr
[dmanr
];
222 // Determine which address registers are used for memory/device accesses
223 if (dmawp
[MCFDMA_DCR
] & MCFDMA_DCR_SINC
) {
224 // Source incrementing, must be memory
225 dmalp
[MCFDMA_SAR
] = a
;
226 // Set dest address, must be device
227 dmalp
[MCFDMA_DAR
] = dma_device_address
[dmanr
];
229 // Destination incrementing, must be memory
230 dmalp
[MCFDMA_DAR
] = a
;
231 // Set source address, must be device
232 dmalp
[MCFDMA_SAR
] = dma_device_address
[dmanr
];
236 printk("%s(%d): dmanr=%d DCR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
237 __FILE__
, __LINE__
, dmanr
, (int) &dmawp
[MCFDMA_DCR
], dmawp
[MCFDMA_DCR
],
238 (int) &dmalp
[MCFDMA_SAR
], dmalp
[MCFDMA_SAR
],
239 (int) &dmalp
[MCFDMA_DAR
], dmalp
[MCFDMA_DAR
]);
244 * Specific for Coldfire - sets device address.
245 * Should be called after the mode set call, and before set DMA address.
247 static __inline__
void set_dma_device_addr(unsigned int dmanr
, unsigned int a
)
250 printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr
, a
);
253 dma_device_address
[dmanr
] = a
;
257 * NOTE 2: "count" represents _bytes_.
259 static __inline__
void set_dma_count(unsigned int dmanr
, unsigned int count
)
261 volatile unsigned short *dmawp
;
264 printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr
, count
);
267 dmawp
= (unsigned short *) dma_base_addr
[dmanr
];
268 dmawp
[MCFDMA_BCR
] = (unsigned short)count
;
272 * Get DMA residue count. After a DMA transfer, this
273 * should return zero. Reading this while a DMA transfer is
274 * still in progress will return unpredictable results.
275 * Otherwise, it returns the number of _bytes_ left to transfer.
277 static __inline__
int get_dma_residue(unsigned int dmanr
)
279 volatile unsigned short *dmawp
;
280 unsigned short count
;
283 printk("get_dma_residue(dmanr=%d)\n", dmanr
);
286 dmawp
= (unsigned short *) dma_base_addr
[dmanr
];
287 count
= dmawp
[MCFDMA_BCR
];
290 #else /* CONFIG_M5272 is defined */
293 * The MCF5272 DMA controller is very different than the controller defined above
294 * in terms of register mapping. For instance, with the exception of the 16-bit
295 * interrupt register (IRQ#85, for reference), all of the registers are 32-bit.
297 * The big difference, however, is the lack of device-requested DMA. All modes
298 * are dual address transfer, and there is no 'device' setup or direction bit.
299 * You can DMA between a device and memory, between memory and memory, or even between
300 * two devices directly, with any combination of incrementing and non-incrementing
301 * addresses you choose. This puts a crimp in distinguishing between the 'device
302 * address' set up by set_dma_device_addr.
304 * Therefore, there are two options. One is to use set_dma_addr and set_dma_device_addr,
305 * which will act exactly as above in -- it will look to see if the source is set to
306 * autoincrement, and if so it will make the source use the set_dma_addr value and the
307 * destination the set_dma_device_addr value. Otherwise the source will be set to the
308 * set_dma_device_addr value and the destination will get the set_dma_addr value.
310 * The other is to use the provided set_dma_src_addr and set_dma_dest_addr functions
311 * and make it explicit. Depending on what you're doing, one of these two should work
312 * for you, but don't mix them in the same transfer setup.
315 /* enable/disable a specific DMA channel */
316 static __inline__
void enable_dma(unsigned int dmanr
)
318 volatile unsigned int *dmalp
;
321 printk("enable_dma(dmanr=%d)\n", dmanr
);
324 dmalp
= (unsigned int *) dma_base_addr
[dmanr
];
325 dmalp
[MCFDMA_DMR
] |= MCFDMA_DMR_EN
;
328 static __inline__
void disable_dma(unsigned int dmanr
)
330 volatile unsigned int *dmalp
;
333 printk("disable_dma(dmanr=%d)\n", dmanr
);
336 dmalp
= (unsigned int *) dma_base_addr
[dmanr
];
338 /* Turn off external requests, and stop any DMA in progress */
339 dmalp
[MCFDMA_DMR
] &= ~MCFDMA_DMR_EN
;
340 dmalp
[MCFDMA_DMR
] |= MCFDMA_DMR_RESET
;
344 * Clear the 'DMA Pointer Flip Flop'.
345 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
346 * Use this once to initialize the FF to a known state.
347 * After that, keep track of it. :-)
348 * --- In order to do that, the DMA routines below should ---
349 * --- only be used while interrupts are disabled! ---
351 * This is a NOP for ColdFire. Provide a stub for compatibility.
353 static __inline__
void clear_dma_ff(unsigned int dmanr
)
357 /* set mode (above) for a specific DMA channel */
358 static __inline__
void set_dma_mode(unsigned int dmanr
, char mode
)
361 volatile unsigned int *dmalp
;
362 volatile unsigned short *dmawp
;
365 printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr
, mode
);
367 dmalp
= (unsigned int *) dma_base_addr
[dmanr
];
368 dmawp
= (unsigned short *) dma_base_addr
[dmanr
];
370 // Clear config errors
371 dmalp
[MCFDMA_DMR
] |= MCFDMA_DMR_RESET
;
373 // Set command register
375 MCFDMA_DMR_RQM_DUAL
| // Mandatory Request Mode setting
376 MCFDMA_DMR_DSTT_SD
| // Set up addressing types; set to supervisor-data.
377 MCFDMA_DMR_SRCT_SD
| // Set up addressing types; set to supervisor-data.
378 // source static-address-mode
379 ((mode
& DMA_MODE_SRC_SA_BIT
) ? MCFDMA_DMR_SRCM_SA
: MCFDMA_DMR_SRCM_IA
) |
380 // dest static-address-mode
381 ((mode
& DMA_MODE_DES_SA_BIT
) ? MCFDMA_DMR_DSTM_SA
: MCFDMA_DMR_DSTM_IA
) |
382 // burst, 32 bit, 16 bit or 8 bit transfers are separately configurable on the MCF5272
383 (((mode
& DMA_MODE_SSIZE_MASK
) >> DMA_MODE_SSIZE_OFF
) << MCFDMA_DMR_DSTS_OFF
) |
384 (((mode
& DMA_MODE_SSIZE_MASK
) >> DMA_MODE_SSIZE_OFF
) << MCFDMA_DMR_SRCS_OFF
);
386 dmawp
[MCFDMA_DIR
] |= MCFDMA_DIR_ASCEN
; /* Enable completion interrupts */
389 printk("%s(%d): dmanr=%d DMR[%x]=%x DIR[%x]=%x\n", __FILE__
, __LINE__
,
390 dmanr
, (int) &dmalp
[MCFDMA_DMR
], dmabp
[MCFDMA_DMR
],
391 (int) &dmawp
[MCFDMA_DIR
], dmawp
[MCFDMA_DIR
]);
395 /* Set transfer address for specific DMA channel */
396 static __inline__
void set_dma_addr(unsigned int dmanr
, unsigned int a
)
398 volatile unsigned int *dmalp
;
401 printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr
, a
);
404 dmalp
= (unsigned int *) dma_base_addr
[dmanr
];
406 // Determine which address registers are used for memory/device accesses
407 if (dmalp
[MCFDMA_DMR
] & MCFDMA_DMR_SRCM
) {
408 // Source incrementing, must be memory
409 dmalp
[MCFDMA_DSAR
] = a
;
410 // Set dest address, must be device
411 dmalp
[MCFDMA_DDAR
] = dma_device_address
[dmanr
];
413 // Destination incrementing, must be memory
414 dmalp
[MCFDMA_DDAR
] = a
;
415 // Set source address, must be device
416 dmalp
[MCFDMA_DSAR
] = dma_device_address
[dmanr
];
420 printk("%s(%d): dmanr=%d DMR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
421 __FILE__
, __LINE__
, dmanr
, (int) &dmawp
[MCFDMA_DMR
], dmawp
[MCFDMA_DMR
],
422 (int) &dmalp
[MCFDMA_DSAR
], dmalp
[MCFDMA_DSAR
],
423 (int) &dmalp
[MCFDMA_DDAR
], dmalp
[MCFDMA_DDAR
]);
428 * Specific for Coldfire - sets device address.
429 * Should be called after the mode set call, and before set DMA address.
431 static __inline__
void set_dma_device_addr(unsigned int dmanr
, unsigned int a
)
434 printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr
, a
);
437 dma_device_address
[dmanr
] = a
;
441 * NOTE 2: "count" represents _bytes_.
443 * NOTE 3: While a 32-bit register, "count" is only a maximum 24-bit value.
445 static __inline__
void set_dma_count(unsigned int dmanr
, unsigned int count
)
447 volatile unsigned int *dmalp
;
450 printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr
, count
);
453 dmalp
= (unsigned int *) dma_base_addr
[dmanr
];
454 dmalp
[MCFDMA_DBCR
] = count
;
458 * Get DMA residue count. After a DMA transfer, this
459 * should return zero. Reading this while a DMA transfer is
460 * still in progress will return unpredictable results.
461 * Otherwise, it returns the number of _bytes_ left to transfer.
463 static __inline__
int get_dma_residue(unsigned int dmanr
)
465 volatile unsigned int *dmalp
;
469 printk("get_dma_residue(dmanr=%d)\n", dmanr
);
472 dmalp
= (unsigned int *) dma_base_addr
[dmanr
];
473 count
= dmalp
[MCFDMA_DBCR
];
477 #endif /* !defined(CONFIG_M5272) */
478 #endif /* CONFIG_COLDFIRE */
480 #define MAX_DMA_CHANNELS 8
482 /* Don't define MAX_DMA_ADDRESS; it's useless on the m68k/coldfire and any
483 occurrence should be flagged as an error. */
484 /* under 2.4 it is actually needed by the new bootmem allocator */
485 #define MAX_DMA_ADDRESS PAGE_OFFSET
487 /* These are in kernel/dma.c: */
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 */
491 #endif /* _M68K_DMA_H */