#ifndef __ASM_ARM_DMA_H #define __ASM_ARM_DMA_H /* * This is the maximum virtual address which can be DMA'd from. */ #ifndef CONFIG_ZONE_DMA #define MAX_DMA_ADDRESS 0xffffffffUL #else #define MAX_DMA_ADDRESS ({ \ extern unsigned long arm_dma_zone_size; \ arm_dma_zone_size ? \ (PAGE_OFFSET + arm_dma_zone_size) : 0xffffffffUL; }) #endif #ifdef CONFIG_ISA_DMA_API /* * This is used to support drivers written for the x86 ISA DMA API. * It should not be re-used except for that purpose. */ #include <linux/spinlock.h> #include <asm/scatterlist.h> #include <mach/isa-dma.h> /* * The DMA modes reflect the settings for the ISA DMA controller */ #define DMA_MODE_MASK 0xcc #define DMA_MODE_READ 0x44 #define DMA_MODE_WRITE 0x48 #define DMA_MODE_CASCADE 0xc0 #define DMA_AUTOINIT 0x10 extern raw_spinlock_t dma_spin_lock; static inline unsigned long claim_dma_lock(void) { unsigned long flags; raw_spin_lock_irqsave(&dma_spin_lock, flags); return flags; } static inline void release_dma_lock(unsigned long flags) { raw_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(chan) /* 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(unsigned int chan, char pagenr); /* Request a DMA channel * * Some architectures may need to do allocate an interrupt */ extern int request_dma(unsigned int chan, const char * device_id); /* Free a DMA channel * * Some architectures may need to do free an interrupt */ extern void free_dma(unsigned int chan); /* 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(unsigned int chan); /* Disable DMA for this channel * * On some architectures, this may have other side effects like * disabling an interrupt or whatever. */ extern void disable_dma(unsigned int chan); /* Test whether the specified channel has an active DMA transfer */ extern int dma_channel_active(unsigned int chan); /* 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(unsigned int chan, 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(unsigned int chan, void *addr); #define set_dma_addr(chan, addr) \ __set_dma_addr(chan, (void *)__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(unsigned int chan, 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(unsigned int chan, unsigned int mode); /* Set the transfer speed for this channel */ extern void set_dma_speed(unsigned int chan, 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(unsigned int chan); #ifndef NO_DMA #define NO_DMA 255 #endif #endif /* CONFIG_ISA_DMA_API */ #ifdef CONFIG_PCI extern int isa_dma_bridge_buggy; #else #define isa_dma_bridge_buggy (0) #endif #endif /* __ASM_ARM_DMA_H */