mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-25 19:07:46 +00:00
2fb3ec5c95
The values of ISA_DMA_THRESHOLD and MAX_DMA_ADDRESS are related; one is the physical/bus address, the other is the virtual address. Both need to be kept in step, so rather than having platforms define both, allow them to define a single macro which sets both of these macros appropraitely. Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
152 lines
4.0 KiB
C
152 lines
4.0 KiB
C
#ifndef __ASM_ARM_DMA_H
|
|
#define __ASM_ARM_DMA_H
|
|
|
|
#include <asm/memory.h>
|
|
|
|
/*
|
|
* This is the maximum virtual address which can be DMA'd from.
|
|
*/
|
|
#ifndef ARM_DMA_ZONE_SIZE
|
|
#define MAX_DMA_ADDRESS 0xffffffff
|
|
#else
|
|
#define MAX_DMA_ADDRESS (PAGE_OFFSET + ARM_DMA_ZONE_SIZE)
|
|
#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/system.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 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(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, 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 */
|