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authorThomas Gleixner <tglx@linutronix.de>2008-01-30 07:30:20 -0500
committerIngo Molnar <mingo@elte.hu>2008-01-30 07:30:20 -0500
commitf28b8d608829aecd7343015a0df89f6b6e89d391 (patch)
tree2cee1e1791d1009066f6176a84f55a64e9e3815e /include/asm-x86/dma.h
parent2f18e47c89f1a29cc815cd225b72dd7fd86acffe (diff)
x86: merge include/asm-x86/dma.h
Almost identical. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'include/asm-x86/dma.h')
-rw-r--r--include/asm-x86/dma.h318
1 files changed, 316 insertions, 2 deletions
diff --git a/include/asm-x86/dma.h b/include/asm-x86/dma.h
index 9f936c61a4e5..e9733ce89880 100644
--- a/include/asm-x86/dma.h
+++ b/include/asm-x86/dma.h
@@ -1,5 +1,319 @@
1/*
2 * linux/include/asm/dma.h: Defines for using and allocating dma channels.
3 * Written by Hennus Bergman, 1992.
4 * High DMA channel support & info by Hannu Savolainen
5 * and John Boyd, Nov. 1992.
6 */
7
8#ifndef _ASM_X86_DMA_H
9#define _ASM_X86_DMA_H
10
11#include <linux/spinlock.h> /* And spinlocks */
12#include <asm/io.h> /* need byte IO */
13#include <linux/delay.h>
14
15
16#ifdef HAVE_REALLY_SLOW_DMA_CONTROLLER
17#define dma_outb outb_p
18#else
19#define dma_outb outb
20#endif
21
22#define dma_inb inb
23
24/*
25 * NOTES about DMA transfers:
26 *
27 * controller 1: channels 0-3, byte operations, ports 00-1F
28 * controller 2: channels 4-7, word operations, ports C0-DF
29 *
30 * - ALL registers are 8 bits only, regardless of transfer size
31 * - channel 4 is not used - cascades 1 into 2.
32 * - channels 0-3 are byte - addresses/counts are for physical bytes
33 * - channels 5-7 are word - addresses/counts are for physical words
34 * - transfers must not cross physical 64K (0-3) or 128K (5-7) boundaries
35 * - transfer count loaded to registers is 1 less than actual count
36 * - controller 2 offsets are all even (2x offsets for controller 1)
37 * - page registers for 5-7 don't use data bit 0, represent 128K pages
38 * - page registers for 0-3 use bit 0, represent 64K pages
39 *
40 * DMA transfers are limited to the lower 16MB of _physical_ memory.
41 * Note that addresses loaded into registers must be _physical_ addresses,
42 * not logical addresses (which may differ if paging is active).
43 *
44 * Address mapping for channels 0-3:
45 *
46 * A23 ... A16 A15 ... A8 A7 ... A0 (Physical addresses)
47 * | ... | | ... | | ... |
48 * | ... | | ... | | ... |
49 * | ... | | ... | | ... |
50 * P7 ... P0 A7 ... A0 A7 ... A0
51 * | Page | Addr MSB | Addr LSB | (DMA registers)
52 *
53 * Address mapping for channels 5-7:
54 *
55 * A23 ... A17 A16 A15 ... A9 A8 A7 ... A1 A0 (Physical addresses)
56 * | ... | \ \ ... \ \ \ ... \ \
57 * | ... | \ \ ... \ \ \ ... \ (not used)
58 * | ... | \ \ ... \ \ \ ... \
59 * P7 ... P1 (0) A7 A6 ... A0 A7 A6 ... A0
60 * | Page | Addr MSB | Addr LSB | (DMA registers)
61 *
62 * Again, channels 5-7 transfer _physical_ words (16 bits), so addresses
63 * and counts _must_ be word-aligned (the lowest address bit is _ignored_ at
64 * the hardware level, so odd-byte transfers aren't possible).
65 *
66 * Transfer count (_not # bytes_) is limited to 64K, represented as actual
67 * count - 1 : 64K => 0xFFFF, 1 => 0x0000. Thus, count is always 1 or more,
68 * and up to 128K bytes may be transferred on channels 5-7 in one operation.
69 *
70 */
71
72#define MAX_DMA_CHANNELS 8
73
1#ifdef CONFIG_X86_32 74#ifdef CONFIG_X86_32
2# include "dma_32.h" 75
76/* The maximum address that we can perform a DMA transfer to on this platform */
77#define MAX_DMA_ADDRESS (PAGE_OFFSET+0x1000000)
78
79#else
80
81/* 16MB ISA DMA zone */
82#define MAX_DMA_PFN ((16*1024*1024) >> PAGE_SHIFT)
83
84/* 4GB broken PCI/AGP hardware bus master zone */
85#define MAX_DMA32_PFN ((4UL*1024*1024*1024) >> PAGE_SHIFT)
86
87/* Compat define for old dma zone */
88#define MAX_DMA_ADDRESS ((unsigned long)__va(MAX_DMA_PFN << PAGE_SHIFT))
89
90#endif
91
92/* 8237 DMA controllers */
93#define IO_DMA1_BASE 0x00 /* 8 bit slave DMA, channels 0..3 */
94#define IO_DMA2_BASE 0xC0 /* 16 bit master DMA, ch 4(=slave input)..7 */
95
96/* DMA controller registers */
97#define DMA1_CMD_REG 0x08 /* command register (w) */
98#define DMA1_STAT_REG 0x08 /* status register (r) */
99#define DMA1_REQ_REG 0x09 /* request register (w) */
100#define DMA1_MASK_REG 0x0A /* single-channel mask (w) */
101#define DMA1_MODE_REG 0x0B /* mode register (w) */
102#define DMA1_CLEAR_FF_REG 0x0C /* clear pointer flip-flop (w) */
103#define DMA1_TEMP_REG 0x0D /* Temporary Register (r) */
104#define DMA1_RESET_REG 0x0D /* Master Clear (w) */
105#define DMA1_CLR_MASK_REG 0x0E /* Clear Mask */
106#define DMA1_MASK_ALL_REG 0x0F /* all-channels mask (w) */
107
108#define DMA2_CMD_REG 0xD0 /* command register (w) */
109#define DMA2_STAT_REG 0xD0 /* status register (r) */
110#define DMA2_REQ_REG 0xD2 /* request register (w) */
111#define DMA2_MASK_REG 0xD4 /* single-channel mask (w) */
112#define DMA2_MODE_REG 0xD6 /* mode register (w) */
113#define DMA2_CLEAR_FF_REG 0xD8 /* clear pointer flip-flop (w) */
114#define DMA2_TEMP_REG 0xDA /* Temporary Register (r) */
115#define DMA2_RESET_REG 0xDA /* Master Clear (w) */
116#define DMA2_CLR_MASK_REG 0xDC /* Clear Mask */
117#define DMA2_MASK_ALL_REG 0xDE /* all-channels mask (w) */
118
119#define DMA_ADDR_0 0x00 /* DMA address registers */
120#define DMA_ADDR_1 0x02
121#define DMA_ADDR_2 0x04
122#define DMA_ADDR_3 0x06
123#define DMA_ADDR_4 0xC0
124#define DMA_ADDR_5 0xC4
125#define DMA_ADDR_6 0xC8
126#define DMA_ADDR_7 0xCC
127
128#define DMA_CNT_0 0x01 /* DMA count registers */
129#define DMA_CNT_1 0x03
130#define DMA_CNT_2 0x05
131#define DMA_CNT_3 0x07
132#define DMA_CNT_4 0xC2
133#define DMA_CNT_5 0xC6
134#define DMA_CNT_6 0xCA
135#define DMA_CNT_7 0xCE
136
137#define DMA_PAGE_0 0x87 /* DMA page registers */
138#define DMA_PAGE_1 0x83
139#define DMA_PAGE_2 0x81
140#define DMA_PAGE_3 0x82
141#define DMA_PAGE_5 0x8B
142#define DMA_PAGE_6 0x89
143#define DMA_PAGE_7 0x8A
144
145/* I/O to memory, no autoinit, increment, single mode */
146#define DMA_MODE_READ 0x44
147/* memory to I/O, no autoinit, increment, single mode */
148#define DMA_MODE_WRITE 0x48
149/* pass thru DREQ->HRQ, DACK<-HLDA only */
150#define DMA_MODE_CASCADE 0xC0
151
152#define DMA_AUTOINIT 0x10
153
154
155extern spinlock_t dma_spin_lock;
156
157static __inline__ unsigned long claim_dma_lock(void)
158{
159 unsigned long flags;
160 spin_lock_irqsave(&dma_spin_lock, flags);
161 return flags;
162}
163
164static __inline__ void release_dma_lock(unsigned long flags)
165{
166 spin_unlock_irqrestore(&dma_spin_lock, flags);
167}
168
169/* enable/disable a specific DMA channel */
170static __inline__ void enable_dma(unsigned int dmanr)
171{
172 if (dmanr <= 3)
173 dma_outb(dmanr, DMA1_MASK_REG);
174 else
175 dma_outb(dmanr & 3, DMA2_MASK_REG);
176}
177
178static __inline__ void disable_dma(unsigned int dmanr)
179{
180 if (dmanr <= 3)
181 dma_outb(dmanr | 4, DMA1_MASK_REG);
182 else
183 dma_outb((dmanr & 3) | 4, DMA2_MASK_REG);
184}
185
186/* Clear the 'DMA Pointer Flip Flop'.
187 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
188 * Use this once to initialize the FF to a known state.
189 * After that, keep track of it. :-)
190 * --- In order to do that, the DMA routines below should ---
191 * --- only be used while holding the DMA lock ! ---
192 */
193static __inline__ void clear_dma_ff(unsigned int dmanr)
194{
195 if (dmanr <= 3)
196 dma_outb(0, DMA1_CLEAR_FF_REG);
197 else
198 dma_outb(0, DMA2_CLEAR_FF_REG);
199}
200
201/* set mode (above) for a specific DMA channel */
202static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
203{
204 if (dmanr <= 3)
205 dma_outb(mode | dmanr, DMA1_MODE_REG);
206 else
207 dma_outb(mode | (dmanr & 3), DMA2_MODE_REG);
208}
209
210/* Set only the page register bits of the transfer address.
211 * This is used for successive transfers when we know the contents of
212 * the lower 16 bits of the DMA current address register, but a 64k boundary
213 * may have been crossed.
214 */
215static __inline__ void set_dma_page(unsigned int dmanr, char pagenr)
216{
217 switch (dmanr) {
218 case 0:
219 dma_outb(pagenr, DMA_PAGE_0);
220 break;
221 case 1:
222 dma_outb(pagenr, DMA_PAGE_1);
223 break;
224 case 2:
225 dma_outb(pagenr, DMA_PAGE_2);
226 break;
227 case 3:
228 dma_outb(pagenr, DMA_PAGE_3);
229 break;
230 case 5:
231 dma_outb(pagenr & 0xfe, DMA_PAGE_5);
232 break;
233 case 6:
234 dma_outb(pagenr & 0xfe, DMA_PAGE_6);
235 break;
236 case 7:
237 dma_outb(pagenr & 0xfe, DMA_PAGE_7);
238 break;
239 }
240}
241
242
243/* Set transfer address & page bits for specific DMA channel.
244 * Assumes dma flipflop is clear.
245 */
246static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
247{
248 set_dma_page(dmanr, a>>16);
249 if (dmanr <= 3) {
250 dma_outb(a & 0xff, ((dmanr & 3) << 1) + IO_DMA1_BASE);
251 dma_outb((a >> 8) & 0xff, ((dmanr & 3) << 1) + IO_DMA1_BASE);
252 } else {
253 dma_outb((a >> 1) & 0xff, ((dmanr & 3) << 2) + IO_DMA2_BASE);
254 dma_outb((a >> 9) & 0xff, ((dmanr & 3) << 2) + IO_DMA2_BASE);
255 }
256}
257
258
259/* Set transfer size (max 64k for DMA0..3, 128k for DMA5..7) for
260 * a specific DMA channel.
261 * You must ensure the parameters are valid.
262 * NOTE: from a manual: "the number of transfers is one more
263 * than the initial word count"! This is taken into account.
264 * Assumes dma flip-flop is clear.
265 * NOTE 2: "count" represents _bytes_ and must be even for channels 5-7.
266 */
267static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
268{
269 count--;
270 if (dmanr <= 3) {
271 dma_outb(count & 0xff, ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE);
272 dma_outb((count >> 8) & 0xff,
273 ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE);
274 } else {
275 dma_outb((count >> 1) & 0xff,
276 ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE);
277 dma_outb((count >> 9) & 0xff,
278 ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE);
279 }
280}
281
282
283/* Get DMA residue count. After a DMA transfer, this
284 * should return zero. Reading this while a DMA transfer is
285 * still in progress will return unpredictable results.
286 * If called before the channel has been used, it may return 1.
287 * Otherwise, it returns the number of _bytes_ left to transfer.
288 *
289 * Assumes DMA flip-flop is clear.
290 */
291static __inline__ int get_dma_residue(unsigned int dmanr)
292{
293 unsigned int io_port;
294 /* using short to get 16-bit wrap around */
295 unsigned short count;
296
297 io_port = (dmanr <= 3) ? ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE
298 : ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE;
299
300 count = 1 + dma_inb(io_port);
301 count += dma_inb(io_port) << 8;
302
303 return (dmanr <= 3) ? count : (count << 1);
304}
305
306
307/* These are in kernel/dma.c: */
308extern int request_dma(unsigned int dmanr, const char *device_id);
309extern void free_dma(unsigned int dmanr);
310
311/* From PCI */
312
313#ifdef CONFIG_PCI
314extern int isa_dma_bridge_buggy;
3#else 315#else
4# include "dma_64.h" 316#define isa_dma_bridge_buggy (0)
5#endif 317#endif
318
319#endif /* _ASM_X86_DMA_H */