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b8f114db JL |
1 | #ifndef _ASM_POWERPC_DMA_H |
2 | #define _ASM_POWERPC_DMA_H | |
88ced031 | 3 | #ifdef __KERNEL__ |
b8f114db | 4 | |
1da177e4 | 5 | /* |
b8f114db | 6 | * Defines for using and allocating dma channels. |
1da177e4 LT |
7 | * Written by Hennus Bergman, 1992. |
8 | * High DMA channel support & info by Hannu Savolainen | |
9 | * and John Boyd, Nov. 1992. | |
10 | * Changes for ppc sound by Christoph Nadig | |
11 | */ | |
12 | ||
1da177e4 LT |
13 | /* |
14 | * Note: Adapted for PowerPC by Gary Thomas | |
15 | * Modified by Cort Dougan <cort@cs.nmt.edu> | |
16 | * | |
17 | * None of this really applies for Power Macintoshes. There is | |
18 | * basically just enough here to get kernel/dma.c to compile. | |
19 | * | |
20 | * There may be some comments or restrictions made here which are | |
21 | * not valid for the PReP platform. Take what you read | |
22 | * with a grain of salt. | |
23 | */ | |
24 | ||
b8f114db JL |
25 | #include <asm/io.h> |
26 | #include <linux/spinlock.h> | |
1da177e4 LT |
27 | |
28 | #ifndef MAX_DMA_CHANNELS | |
29 | #define MAX_DMA_CHANNELS 8 | |
30 | #endif | |
31 | ||
32 | /* The maximum address that we can perform a DMA transfer to on this platform */ | |
33 | /* Doesn't really apply... */ | |
b8f114db | 34 | #define MAX_DMA_ADDRESS (~0UL) |
1da177e4 | 35 | |
1da177e4 LT |
36 | #ifdef HAVE_REALLY_SLOW_DMA_CONTROLLER |
37 | #define dma_outb outb_p | |
38 | #else | |
39 | #define dma_outb outb | |
40 | #endif | |
41 | ||
42 | #define dma_inb inb | |
43 | ||
44 | /* | |
45 | * NOTES about DMA transfers: | |
46 | * | |
47 | * controller 1: channels 0-3, byte operations, ports 00-1F | |
48 | * controller 2: channels 4-7, word operations, ports C0-DF | |
49 | * | |
50 | * - ALL registers are 8 bits only, regardless of transfer size | |
51 | * - channel 4 is not used - cascades 1 into 2. | |
52 | * - channels 0-3 are byte - addresses/counts are for physical bytes | |
53 | * - channels 5-7 are word - addresses/counts are for physical words | |
54 | * - transfers must not cross physical 64K (0-3) or 128K (5-7) boundaries | |
55 | * - transfer count loaded to registers is 1 less than actual count | |
56 | * - controller 2 offsets are all even (2x offsets for controller 1) | |
57 | * - page registers for 5-7 don't use data bit 0, represent 128K pages | |
58 | * - page registers for 0-3 use bit 0, represent 64K pages | |
59 | * | |
60 | * On PReP, DMA transfers are limited to the lower 16MB of _physical_ memory. | |
61 | * On CHRP, the W83C553F (and VLSI Tollgate?) support full 32 bit addressing. | |
62 | * Note that addresses loaded into registers must be _physical_ addresses, | |
63 | * not logical addresses (which may differ if paging is active). | |
64 | * | |
65 | * Address mapping for channels 0-3: | |
66 | * | |
67 | * A23 ... A16 A15 ... A8 A7 ... A0 (Physical addresses) | |
68 | * | ... | | ... | | ... | | |
69 | * | ... | | ... | | ... | | |
70 | * | ... | | ... | | ... | | |
71 | * P7 ... P0 A7 ... A0 A7 ... A0 | |
72 | * | Page | Addr MSB | Addr LSB | (DMA registers) | |
73 | * | |
74 | * Address mapping for channels 5-7: | |
75 | * | |
76 | * A23 ... A17 A16 A15 ... A9 A8 A7 ... A1 A0 (Physical addresses) | |
77 | * | ... | \ \ ... \ \ \ ... \ \ | |
78 | * | ... | \ \ ... \ \ \ ... \ (not used) | |
79 | * | ... | \ \ ... \ \ \ ... \ | |
80 | * P7 ... P1 (0) A7 A6 ... A0 A7 A6 ... A0 | |
81 | * | Page | Addr MSB | Addr LSB | (DMA registers) | |
82 | * | |
83 | * Again, channels 5-7 transfer _physical_ words (16 bits), so addresses | |
84 | * and counts _must_ be word-aligned (the lowest address bit is _ignored_ at | |
85 | * the hardware level, so odd-byte transfers aren't possible). | |
86 | * | |
87 | * Transfer count (_not # bytes_) is limited to 64K, represented as actual | |
88 | * count - 1 : 64K => 0xFFFF, 1 => 0x0000. Thus, count is always 1 or more, | |
89 | * and up to 128K bytes may be transferred on channels 5-7 in one operation. | |
90 | * | |
91 | */ | |
92 | ||
1da177e4 LT |
93 | /* 8237 DMA controllers */ |
94 | #define IO_DMA1_BASE 0x00 /* 8 bit slave DMA, channels 0..3 */ | |
95 | #define IO_DMA2_BASE 0xC0 /* 16 bit master DMA, ch 4(=slave input)..7 */ | |
96 | ||
97 | /* DMA controller registers */ | |
98 | #define DMA1_CMD_REG 0x08 /* command register (w) */ | |
99 | #define DMA1_STAT_REG 0x08 /* status register (r) */ | |
100 | #define DMA1_REQ_REG 0x09 /* request register (w) */ | |
101 | #define DMA1_MASK_REG 0x0A /* single-channel mask (w) */ | |
102 | #define DMA1_MODE_REG 0x0B /* mode register (w) */ | |
103 | #define DMA1_CLEAR_FF_REG 0x0C /* clear pointer flip-flop (w) */ | |
104 | #define DMA1_TEMP_REG 0x0D /* Temporary Register (r) */ | |
105 | #define DMA1_RESET_REG 0x0D /* Master Clear (w) */ | |
106 | #define DMA1_CLR_MASK_REG 0x0E /* Clear Mask */ | |
107 | #define DMA1_MASK_ALL_REG 0x0F /* all-channels mask (w) */ | |
108 | ||
109 | #define DMA2_CMD_REG 0xD0 /* command register (w) */ | |
110 | #define DMA2_STAT_REG 0xD0 /* status register (r) */ | |
111 | #define DMA2_REQ_REG 0xD2 /* request register (w) */ | |
112 | #define DMA2_MASK_REG 0xD4 /* single-channel mask (w) */ | |
113 | #define DMA2_MODE_REG 0xD6 /* mode register (w) */ | |
114 | #define DMA2_CLEAR_FF_REG 0xD8 /* clear pointer flip-flop (w) */ | |
115 | #define DMA2_TEMP_REG 0xDA /* Temporary Register (r) */ | |
116 | #define DMA2_RESET_REG 0xDA /* Master Clear (w) */ | |
117 | #define DMA2_CLR_MASK_REG 0xDC /* Clear Mask */ | |
118 | #define DMA2_MASK_ALL_REG 0xDE /* all-channels mask (w) */ | |
119 | ||
120 | #define DMA_ADDR_0 0x00 /* DMA address registers */ | |
121 | #define DMA_ADDR_1 0x02 | |
122 | #define DMA_ADDR_2 0x04 | |
123 | #define DMA_ADDR_3 0x06 | |
124 | #define DMA_ADDR_4 0xC0 | |
125 | #define DMA_ADDR_5 0xC4 | |
126 | #define DMA_ADDR_6 0xC8 | |
127 | #define DMA_ADDR_7 0xCC | |
128 | ||
129 | #define DMA_CNT_0 0x01 /* DMA count registers */ | |
130 | #define DMA_CNT_1 0x03 | |
131 | #define DMA_CNT_2 0x05 | |
132 | #define DMA_CNT_3 0x07 | |
133 | #define DMA_CNT_4 0xC2 | |
134 | #define DMA_CNT_5 0xC6 | |
135 | #define DMA_CNT_6 0xCA | |
136 | #define DMA_CNT_7 0xCE | |
137 | ||
138 | #define DMA_LO_PAGE_0 0x87 /* DMA page registers */ | |
139 | #define DMA_LO_PAGE_1 0x83 | |
140 | #define DMA_LO_PAGE_2 0x81 | |
141 | #define DMA_LO_PAGE_3 0x82 | |
142 | #define DMA_LO_PAGE_5 0x8B | |
143 | #define DMA_LO_PAGE_6 0x89 | |
144 | #define DMA_LO_PAGE_7 0x8A | |
145 | ||
146 | #define DMA_HI_PAGE_0 0x487 /* DMA page registers */ | |
147 | #define DMA_HI_PAGE_1 0x483 | |
148 | #define DMA_HI_PAGE_2 0x481 | |
149 | #define DMA_HI_PAGE_3 0x482 | |
150 | #define DMA_HI_PAGE_5 0x48B | |
151 | #define DMA_HI_PAGE_6 0x489 | |
152 | #define DMA_HI_PAGE_7 0x48A | |
153 | ||
154 | #define DMA1_EXT_REG 0x40B | |
155 | #define DMA2_EXT_REG 0x4D6 | |
156 | ||
b8f114db JL |
157 | #ifndef __powerpc64__ |
158 | /* in arch/ppc/kernel/setup.c -- Cort */ | |
159 | extern unsigned int DMA_MODE_WRITE; | |
160 | extern unsigned int DMA_MODE_READ; | |
161 | extern unsigned long ISA_DMA_THRESHOLD; | |
162 | #else | |
163 | #define DMA_MODE_READ 0x44 /* I/O to memory, no autoinit, increment, single mode */ | |
164 | #define DMA_MODE_WRITE 0x48 /* memory to I/O, no autoinit, increment, single mode */ | |
165 | #endif | |
166 | ||
1da177e4 | 167 | #define DMA_MODE_CASCADE 0xC0 /* pass thru DREQ->HRQ, DACK<-HLDA only */ |
b8f114db | 168 | |
1da177e4 LT |
169 | #define DMA_AUTOINIT 0x10 |
170 | ||
171 | extern spinlock_t dma_spin_lock; | |
172 | ||
173 | static __inline__ unsigned long claim_dma_lock(void) | |
174 | { | |
175 | unsigned long flags; | |
176 | spin_lock_irqsave(&dma_spin_lock, flags); | |
177 | return flags; | |
178 | } | |
179 | ||
180 | static __inline__ void release_dma_lock(unsigned long flags) | |
181 | { | |
182 | spin_unlock_irqrestore(&dma_spin_lock, flags); | |
183 | } | |
184 | ||
185 | /* enable/disable a specific DMA channel */ | |
186 | static __inline__ void enable_dma(unsigned int dmanr) | |
187 | { | |
188 | unsigned char ucDmaCmd = 0x00; | |
189 | ||
190 | if (dmanr != 4) { | |
191 | dma_outb(0, DMA2_MASK_REG); /* This may not be enabled */ | |
192 | dma_outb(ucDmaCmd, DMA2_CMD_REG); /* Enable group */ | |
193 | } | |
194 | if (dmanr <= 3) { | |
195 | dma_outb(dmanr, DMA1_MASK_REG); | |
196 | dma_outb(ucDmaCmd, DMA1_CMD_REG); /* Enable group */ | |
b8f114db | 197 | } else { |
1da177e4 | 198 | dma_outb(dmanr & 3, DMA2_MASK_REG); |
b8f114db | 199 | } |
1da177e4 LT |
200 | } |
201 | ||
202 | static __inline__ void disable_dma(unsigned int dmanr) | |
203 | { | |
204 | if (dmanr <= 3) | |
205 | dma_outb(dmanr | 4, DMA1_MASK_REG); | |
206 | else | |
207 | dma_outb((dmanr & 3) | 4, DMA2_MASK_REG); | |
208 | } | |
209 | ||
210 | /* Clear the 'DMA Pointer Flip Flop'. | |
211 | * Write 0 for LSB/MSB, 1 for MSB/LSB access. | |
212 | * Use this once to initialize the FF to a known state. | |
213 | * After that, keep track of it. :-) | |
214 | * --- In order to do that, the DMA routines below should --- | |
215 | * --- only be used while interrupts are disabled! --- | |
216 | */ | |
217 | static __inline__ void clear_dma_ff(unsigned int dmanr) | |
218 | { | |
219 | if (dmanr <= 3) | |
220 | dma_outb(0, DMA1_CLEAR_FF_REG); | |
221 | else | |
222 | dma_outb(0, DMA2_CLEAR_FF_REG); | |
223 | } | |
224 | ||
225 | /* set mode (above) for a specific DMA channel */ | |
226 | static __inline__ void set_dma_mode(unsigned int dmanr, char mode) | |
227 | { | |
228 | if (dmanr <= 3) | |
229 | dma_outb(mode | dmanr, DMA1_MODE_REG); | |
230 | else | |
231 | dma_outb(mode | (dmanr & 3), DMA2_MODE_REG); | |
232 | } | |
233 | ||
234 | /* Set only the page register bits of the transfer address. | |
235 | * This is used for successive transfers when we know the contents of | |
236 | * the lower 16 bits of the DMA current address register, but a 64k boundary | |
237 | * may have been crossed. | |
238 | */ | |
239 | static __inline__ void set_dma_page(unsigned int dmanr, int pagenr) | |
240 | { | |
241 | switch (dmanr) { | |
242 | case 0: | |
243 | dma_outb(pagenr, DMA_LO_PAGE_0); | |
244 | dma_outb(pagenr >> 8, DMA_HI_PAGE_0); | |
245 | break; | |
246 | case 1: | |
247 | dma_outb(pagenr, DMA_LO_PAGE_1); | |
248 | dma_outb(pagenr >> 8, DMA_HI_PAGE_1); | |
249 | break; | |
250 | case 2: | |
251 | dma_outb(pagenr, DMA_LO_PAGE_2); | |
252 | dma_outb(pagenr >> 8, DMA_HI_PAGE_2); | |
253 | break; | |
254 | case 3: | |
255 | dma_outb(pagenr, DMA_LO_PAGE_3); | |
256 | dma_outb(pagenr >> 8, DMA_HI_PAGE_3); | |
257 | break; | |
258 | case 5: | |
83bad1d7 | 259 | dma_outb(pagenr & 0xfe, DMA_LO_PAGE_5); |
1da177e4 LT |
260 | dma_outb(pagenr >> 8, DMA_HI_PAGE_5); |
261 | break; | |
262 | case 6: | |
83bad1d7 | 263 | dma_outb(pagenr & 0xfe, DMA_LO_PAGE_6); |
1da177e4 LT |
264 | dma_outb(pagenr >> 8, DMA_HI_PAGE_6); |
265 | break; | |
266 | case 7: | |
83bad1d7 | 267 | dma_outb(pagenr & 0xfe, DMA_LO_PAGE_7); |
1da177e4 LT |
268 | dma_outb(pagenr >> 8, DMA_HI_PAGE_7); |
269 | break; | |
270 | } | |
271 | } | |
272 | ||
273 | /* Set transfer address & page bits for specific DMA channel. | |
274 | * Assumes dma flipflop is clear. | |
275 | */ | |
276 | static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int phys) | |
277 | { | |
278 | if (dmanr <= 3) { | |
b8f114db JL |
279 | dma_outb(phys & 0xff, |
280 | ((dmanr & 3) << 1) + IO_DMA1_BASE); | |
281 | dma_outb((phys >> 8) & 0xff, | |
282 | ((dmanr & 3) << 1) + IO_DMA1_BASE); | |
1da177e4 | 283 | } else { |
b8f114db JL |
284 | dma_outb((phys >> 1) & 0xff, |
285 | ((dmanr & 3) << 2) + IO_DMA2_BASE); | |
286 | dma_outb((phys >> 9) & 0xff, | |
287 | ((dmanr & 3) << 2) + IO_DMA2_BASE); | |
1da177e4 LT |
288 | } |
289 | set_dma_page(dmanr, phys >> 16); | |
290 | } | |
291 | ||
b8f114db | 292 | |
1da177e4 LT |
293 | /* Set transfer size (max 64k for DMA1..3, 128k for DMA5..7) for |
294 | * a specific DMA channel. | |
295 | * You must ensure the parameters are valid. | |
296 | * NOTE: from a manual: "the number of transfers is one more | |
297 | * than the initial word count"! This is taken into account. | |
298 | * Assumes dma flip-flop is clear. | |
299 | * NOTE 2: "count" represents _bytes_ and must be even for channels 5-7. | |
300 | */ | |
301 | static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count) | |
302 | { | |
303 | count--; | |
304 | if (dmanr <= 3) { | |
b8f114db JL |
305 | dma_outb(count & 0xff, |
306 | ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE); | |
307 | dma_outb((count >> 8) & 0xff, | |
308 | ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE); | |
1da177e4 | 309 | } else { |
b8f114db JL |
310 | dma_outb((count >> 1) & 0xff, |
311 | ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE); | |
312 | dma_outb((count >> 9) & 0xff, | |
313 | ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE); | |
1da177e4 LT |
314 | } |
315 | } | |
316 | ||
b8f114db | 317 | |
1da177e4 LT |
318 | /* Get DMA residue count. After a DMA transfer, this |
319 | * should return zero. Reading this while a DMA transfer is | |
320 | * still in progress will return unpredictable results. | |
321 | * If called before the channel has been used, it may return 1. | |
322 | * Otherwise, it returns the number of _bytes_ left to transfer. | |
323 | * | |
324 | * Assumes DMA flip-flop is clear. | |
325 | */ | |
326 | static __inline__ int get_dma_residue(unsigned int dmanr) | |
327 | { | |
b8f114db JL |
328 | unsigned int io_port = (dmanr <= 3) |
329 | ? ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE | |
1da177e4 LT |
330 | : ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE; |
331 | ||
332 | /* using short to get 16-bit wrap around */ | |
333 | unsigned short count; | |
334 | ||
335 | count = 1 + dma_inb(io_port); | |
336 | count += dma_inb(io_port) << 8; | |
337 | ||
83bad1d7 | 338 | return (dmanr <= 3) ? count : (count << 1); |
1da177e4 LT |
339 | } |
340 | ||
341 | /* These are in kernel/dma.c: */ | |
342 | ||
343 | /* reserve a DMA channel */ | |
344 | extern int request_dma(unsigned int dmanr, const char *device_id); | |
345 | /* release it again */ | |
346 | extern void free_dma(unsigned int dmanr); | |
347 | ||
348 | #ifdef CONFIG_PCI | |
349 | extern int isa_dma_bridge_buggy; | |
350 | #else | |
351 | #define isa_dma_bridge_buggy (0) | |
352 | #endif | |
b8f114db | 353 | |
88ced031 | 354 | #endif /* __KERNEL__ */ |
b8f114db | 355 | #endif /* _ASM_POWERPC_DMA_H */ |