#ifndef __ASM_ARM_DMA_H #define __ASM_ARM_DMA_H typedef unsigned int dmach_t; #include #include #include #include /* * This is the maximum virtual address which can be DMA'd from. */ #ifndef MAX_DMA_ADDRESS #define MAX_DMA_ADDRESS 0xffffffff #endif /* * DMA modes */ typedef unsigned int dmamode_t; #define DMA_MODE_MASK 3 #define DMA_MODE_READ 0 #define DMA_MODE_WRITE 1 #define DMA_MODE_CASCADE 2 #define DMA_AUTOINIT 4 extern spinlock_t dma_spin_lock; static inline unsigned long claim_dma_lock(void) { unsigned long flags; spin_lock_irqsave(&dma_spin_lock, flags); return flags; } static inline void release_dma_lock(unsigned long flags) { spin_unlock_irqrestore(&dma_spin_lock, flags); } /* Clear the 'DMA Pointer Flip Flop'. * Write 0 for LSB/MSB, 1 for MSB/LSB access. */ #define clear_dma_ff(channel) /* Set only the page register bits of the transfer address. * * NOTE: This is an architecture specific function, and should * be hidden from the drivers */ extern void set_dma_page(dmach_t channel, char pagenr); /* Request a DMA channel * * Some architectures may need to do allocate an interrupt */ extern int request_dma(dmach_t channel, const char * device_id); /* Free a DMA channel * * Some architectures may need to do free an interrupt */ extern void free_dma(dmach_t channel); /* Enable DMA for this channel * * On some architectures, this may have other side effects like * enabling an interrupt and setting the DMA registers. */ extern void enable_dma(dmach_t channel); /* Disable DMA for this channel * * On some architectures, this may have other side effects like * disabling an interrupt or whatever. */ extern void disable_dma(dmach_t channel); /* Test whether the specified channel has an active DMA transfer */ extern int dma_channel_active(dmach_t channel); /* Set the DMA scatter gather list for this channel * * This should not be called if a DMA channel is enabled, * especially since some DMA architectures don't update the * DMA address immediately, but defer it to the enable_dma(). */ extern void set_dma_sg(dmach_t channel, struct scatterlist *sg, int nr_sg); /* Set the DMA address for this channel * * This should not be called if a DMA channel is enabled, * especially since some DMA architectures don't update the * DMA address immediately, but defer it to the enable_dma(). */ extern void __set_dma_addr(dmach_t channel, void *addr); #define set_dma_addr(channel, addr) \ __set_dma_addr(channel, bus_to_virt(addr)) /* Set the DMA byte count for this channel * * This should not be called if a DMA channel is enabled, * especially since some DMA architectures don't update the * DMA count immediately, but defer it to the enable_dma(). */ extern void set_dma_count(dmach_t channel, unsigned long count); /* Set the transfer direction for this channel * * This should not be called if a DMA channel is enabled, * especially since some DMA architectures don't update the * DMA transfer direction immediately, but defer it to the * enable_dma(). */ extern void set_dma_mode(dmach_t channel, dmamode_t mode); /* Set the transfer speed for this channel */ extern void set_dma_speed(dmach_t channel, int cycle_ns); /* Get DMA residue count. After a DMA transfer, this * should return zero. Reading this while a DMA transfer is * still in progress will return unpredictable results. * If called before the channel has been used, it may return 1. * Otherwise, it returns the number of _bytes_ left to transfer. */ extern int get_dma_residue(dmach_t channel); #ifndef NO_DMA #define NO_DMA 255 #endif #ifdef CONFIG_PCI extern int isa_dma_bridge_buggy; #else #define isa_dma_bridge_buggy (0) #endif #endif /* _ARM_DMA_H */