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1#ifndef __ASM_ARM_DMA_H
2#define __ASM_ARM_DMA_H
3
4/*
5 * This is the maximum virtual address which can be DMA'd from.
6 */
7#ifndef CONFIG_ZONE_DMA
8#define MAX_DMA_ADDRESS 0xffffffffUL
9#else
10#define MAX_DMA_ADDRESS ({ \
11 extern unsigned long arm_dma_zone_size; \
12 arm_dma_zone_size ? \
13 (PAGE_OFFSET + arm_dma_zone_size) : 0xffffffffUL; })
14#endif
15
16#ifdef CONFIG_ISA_DMA_API
17/*
18 * This is used to support drivers written for the x86 ISA DMA API.
19 * It should not be re-used except for that purpose.
20 */
21#include <linux/spinlock.h>
22#include <asm/scatterlist.h>
23
24#include <mach/isa-dma.h>
25
26/*
27 * The DMA modes reflect the settings for the ISA DMA controller
28 */
29#define DMA_MODE_MASK 0xcc
30
31#define DMA_MODE_READ 0x44
32#define DMA_MODE_WRITE 0x48
33#define DMA_MODE_CASCADE 0xc0
34#define DMA_AUTOINIT 0x10
35
36extern raw_spinlock_t dma_spin_lock;
37
38static inline unsigned long claim_dma_lock(void)
39{
40 unsigned long flags;
41 raw_spin_lock_irqsave(&dma_spin_lock, flags);
42 return flags;
43}
44
45static inline void release_dma_lock(unsigned long flags)
46{
47 raw_spin_unlock_irqrestore(&dma_spin_lock, flags);
48}
49
50/* Clear the 'DMA Pointer Flip Flop'.
51 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
52 */
53#define clear_dma_ff(chan)
54
55/* Set only the page register bits of the transfer address.
56 *
57 * NOTE: This is an architecture specific function, and should
58 * be hidden from the drivers
59 */
60extern void set_dma_page(unsigned int chan, char pagenr);
61
62/* Request a DMA channel
63 *
64 * Some architectures may need to do allocate an interrupt
65 */
66extern int request_dma(unsigned int chan, const char * device_id);
67
68/* Free a DMA channel
69 *
70 * Some architectures may need to do free an interrupt
71 */
72extern void free_dma(unsigned int chan);
73
74/* Enable DMA for this channel
75 *
76 * On some architectures, this may have other side effects like
77 * enabling an interrupt and setting the DMA registers.
78 */
79extern void enable_dma(unsigned int chan);
80
81/* Disable DMA for this channel
82 *
83 * On some architectures, this may have other side effects like
84 * disabling an interrupt or whatever.
85 */
86extern void disable_dma(unsigned int chan);
87
88/* Test whether the specified channel has an active DMA transfer
89 */
90extern int dma_channel_active(unsigned int chan);
91
92/* Set the DMA scatter gather list for this channel
93 *
94 * This should not be called if a DMA channel is enabled,
95 * especially since some DMA architectures don't update the
96 * DMA address immediately, but defer it to the enable_dma().
97 */
98extern void set_dma_sg(unsigned int chan, struct scatterlist *sg, int nr_sg);
99
100/* Set the DMA address for this channel
101 *
102 * This should not be called if a DMA channel is enabled,
103 * especially since some DMA architectures don't update the
104 * DMA address immediately, but defer it to the enable_dma().
105 */
106extern void __set_dma_addr(unsigned int chan, void *addr);
107#define set_dma_addr(chan, addr) \
108 __set_dma_addr(chan, bus_to_virt(addr))
109
110/* Set the DMA byte count for this channel
111 *
112 * This should not be called if a DMA channel is enabled,
113 * especially since some DMA architectures don't update the
114 * DMA count immediately, but defer it to the enable_dma().
115 */
116extern void set_dma_count(unsigned int chan, unsigned long count);
117
118/* Set the transfer direction for this channel
119 *
120 * This should not be called if a DMA channel is enabled,
121 * especially since some DMA architectures don't update the
122 * DMA transfer direction immediately, but defer it to the
123 * enable_dma().
124 */
125extern void set_dma_mode(unsigned int chan, unsigned int mode);
126
127/* Set the transfer speed for this channel
128 */
129extern void set_dma_speed(unsigned int chan, int cycle_ns);
130
131/* Get DMA residue count. After a DMA transfer, this
132 * should return zero. Reading this while a DMA transfer is
133 * still in progress will return unpredictable results.
134 * If called before the channel has been used, it may return 1.
135 * Otherwise, it returns the number of _bytes_ left to transfer.
136 */
137extern int get_dma_residue(unsigned int chan);
138
139#ifndef NO_DMA
140#define NO_DMA 255
141#endif
142
143#endif /* CONFIG_ISA_DMA_API */
144
145#ifdef CONFIG_PCI
146extern int isa_dma_bridge_buggy;
147#else
148#define isa_dma_bridge_buggy (0)
149#endif
150
151#endif /* __ASM_ARM_DMA_H */
1#ifndef __ASM_ARM_DMA_H
2#define __ASM_ARM_DMA_H
3
4/*
5 * This is the maximum virtual address which can be DMA'd from.
6 */
7#ifndef CONFIG_ZONE_DMA
8#define MAX_DMA_ADDRESS 0xffffffffUL
9#else
10#define MAX_DMA_ADDRESS ({ \
11 extern unsigned long arm_dma_zone_size; \
12 arm_dma_zone_size ? \
13 (PAGE_OFFSET + arm_dma_zone_size) : 0xffffffffUL; })
14#endif
15
16#ifdef CONFIG_ISA_DMA_API
17/*
18 * This is used to support drivers written for the x86 ISA DMA API.
19 * It should not be re-used except for that purpose.
20 */
21#include <linux/spinlock.h>
22#include <asm/system.h>
23#include <asm/scatterlist.h>
24
25#include <mach/isa-dma.h>
26
27/*
28 * The DMA modes reflect the settings for the ISA DMA controller
29 */
30#define DMA_MODE_MASK 0xcc
31
32#define DMA_MODE_READ 0x44
33#define DMA_MODE_WRITE 0x48
34#define DMA_MODE_CASCADE 0xc0
35#define DMA_AUTOINIT 0x10
36
37extern spinlock_t dma_spin_lock;
38
39static inline unsigned long claim_dma_lock(void)
40{
41 unsigned long flags;
42 spin_lock_irqsave(&dma_spin_lock, flags);
43 return flags;
44}
45
46static inline void release_dma_lock(unsigned long flags)
47{
48 spin_unlock_irqrestore(&dma_spin_lock, flags);
49}
50
51/* Clear the 'DMA Pointer Flip Flop'.
52 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
53 */
54#define clear_dma_ff(chan)
55
56/* Set only the page register bits of the transfer address.
57 *
58 * NOTE: This is an architecture specific function, and should
59 * be hidden from the drivers
60 */
61extern void set_dma_page(unsigned int chan, char pagenr);
62
63/* Request a DMA channel
64 *
65 * Some architectures may need to do allocate an interrupt
66 */
67extern int request_dma(unsigned int chan, const char * device_id);
68
69/* Free a DMA channel
70 *
71 * Some architectures may need to do free an interrupt
72 */
73extern void free_dma(unsigned int chan);
74
75/* Enable DMA for this channel
76 *
77 * On some architectures, this may have other side effects like
78 * enabling an interrupt and setting the DMA registers.
79 */
80extern void enable_dma(unsigned int chan);
81
82/* Disable DMA for this channel
83 *
84 * On some architectures, this may have other side effects like
85 * disabling an interrupt or whatever.
86 */
87extern void disable_dma(unsigned int chan);
88
89/* Test whether the specified channel has an active DMA transfer
90 */
91extern int dma_channel_active(unsigned int chan);
92
93/* Set the DMA scatter gather list for this channel
94 *
95 * This should not be called if a DMA channel is enabled,
96 * especially since some DMA architectures don't update the
97 * DMA address immediately, but defer it to the enable_dma().
98 */
99extern void set_dma_sg(unsigned int chan, struct scatterlist *sg, int nr_sg);
100
101/* Set the DMA address for this channel
102 *
103 * This should not be called if a DMA channel is enabled,
104 * especially since some DMA architectures don't update the
105 * DMA address immediately, but defer it to the enable_dma().
106 */
107extern void __set_dma_addr(unsigned int chan, void *addr);
108#define set_dma_addr(chan, addr) \
109 __set_dma_addr(chan, bus_to_virt(addr))
110
111/* Set the DMA byte count for this channel
112 *
113 * This should not be called if a DMA channel is enabled,
114 * especially since some DMA architectures don't update the
115 * DMA count immediately, but defer it to the enable_dma().
116 */
117extern void set_dma_count(unsigned int chan, unsigned long count);
118
119/* Set the transfer direction for this channel
120 *
121 * This should not be called if a DMA channel is enabled,
122 * especially since some DMA architectures don't update the
123 * DMA transfer direction immediately, but defer it to the
124 * enable_dma().
125 */
126extern void set_dma_mode(unsigned int chan, unsigned int mode);
127
128/* Set the transfer speed for this channel
129 */
130extern void set_dma_speed(unsigned int chan, int cycle_ns);
131
132/* Get DMA residue count. After a DMA transfer, this
133 * should return zero. Reading this while a DMA transfer is
134 * still in progress will return unpredictable results.
135 * If called before the channel has been used, it may return 1.
136 * Otherwise, it returns the number of _bytes_ left to transfer.
137 */
138extern int get_dma_residue(unsigned int chan);
139
140#ifndef NO_DMA
141#define NO_DMA 255
142#endif
143
144#endif /* CONFIG_ISA_DMA_API */
145
146#ifdef CONFIG_PCI
147extern int isa_dma_bridge_buggy;
148#else
149#define isa_dma_bridge_buggy (0)
150#endif
151
152#endif /* __ASM_ARM_DMA_H */