1 #ifndef __ASM_ARM_DMA_H
2 #define __ASM_ARM_DMA_H
4 typedef unsigned int dmach_t;
6 #include <linux/config.h>
7 #include <linux/spinlock.h>
8 #include <asm/system.h>
9 #include <asm/memory.h>
10 #include <asm/scatterlist.h>
11 #include <asm/arch/dma.h>
16 typedef unsigned int dmamode_t;
18 #define DMA_MODE_MASK 3
20 #define DMA_MODE_READ 0
21 #define DMA_MODE_WRITE 1
22 #define DMA_MODE_CASCADE 2
23 #define DMA_AUTOINIT 4
25 extern spinlock_t dma_spin_lock;
27 static inline unsigned long claim_dma_lock(void)
30 spin_lock_irqsave(&dma_spin_lock, flags);
34 static inline void release_dma_lock(unsigned long flags)
36 spin_unlock_irqrestore(&dma_spin_lock, flags);
39 /* Clear the 'DMA Pointer Flip Flop'.
40 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
42 #define clear_dma_ff(channel)
44 /* Set only the page register bits of the transfer address.
46 * NOTE: This is an architecture specific function, and should
47 * be hidden from the drivers
49 extern void set_dma_page(dmach_t channel, char pagenr);
51 /* Request a DMA channel
53 * Some architectures may need to do allocate an interrupt
55 extern int request_dma(dmach_t channel, const char * device_id);
59 * Some architectures may need to do free an interrupt
61 extern void free_dma(dmach_t channel);
63 /* Enable DMA for this channel
65 * On some architectures, this may have other side effects like
66 * enabling an interrupt and setting the DMA registers.
68 extern void enable_dma(dmach_t channel);
70 /* Disable DMA for this channel
72 * On some architectures, this may have other side effects like
73 * disabling an interrupt or whatever.
75 extern void disable_dma(dmach_t channel);
77 /* Test whether the specified channel has an active DMA transfer
79 extern int dma_channel_active(dmach_t channel);
81 /* Set the DMA scatter gather list for this channel
83 * This should not be called if a DMA channel is enabled,
84 * especially since some DMA architectures don't update the
85 * DMA address immediately, but defer it to the enable_dma().
87 extern void set_dma_sg(dmach_t channel, struct scatterlist *sg, int nr_sg);
89 /* Set the DMA address for this channel
91 * This should not be called if a DMA channel is enabled,
92 * especially since some DMA architectures don't update the
93 * DMA address immediately, but defer it to the enable_dma().
95 extern void set_dma_addr(dmach_t channel, unsigned long physaddr);
97 /* Set the DMA byte count for this channel
99 * This should not be called if a DMA channel is enabled,
100 * especially since some DMA architectures don't update the
101 * DMA count immediately, but defer it to the enable_dma().
103 extern void set_dma_count(dmach_t channel, unsigned long count);
105 /* Set the transfer direction for this channel
107 * This should not be called if a DMA channel is enabled,
108 * especially since some DMA architectures don't update the
109 * DMA transfer direction immediately, but defer it to the
112 extern void set_dma_mode(dmach_t channel, dmamode_t mode);
114 /* Set the transfer speed for this channel
116 extern void set_dma_speed(dmach_t channel, int cycle_ns);
118 /* Get DMA residue count. After a DMA transfer, this
119 * should return zero. Reading this while a DMA transfer is
120 * still in progress will return unpredictable results.
121 * If called before the channel has been used, it may return 1.
122 * Otherwise, it returns the number of _bytes_ left to transfer.
124 extern int get_dma_residue(dmach_t channel);
131 extern int isa_dma_bridge_buggy;
133 #define isa_dma_bridge_buggy (0)
136 #ifndef arch_adjust_zones
137 #define arch_adjust_zones(node,size,holes)
140 #endif /* _ARM_DMA_H */