| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174 | /* * linux/include/asm/dma.h: Defines for using and allocating dma channels. * Written by Hennus Bergman, 1992. * High DMA channel support & info by Hannu Savolainen * and John Boyd, Nov. 1992. * * NOTE: all this is true *only* for ISA/EISA expansions on Mips boards * and can only be used for expansion cards. Onboard DMA controllers, such * as the R4030 on Jazz boards behave totally different! */#ifndef _ASM_DMA_H#define _ASM_DMA_H#include <asm/io.h>			/* need byte IO */#include <linux/spinlock.h>		/* And spinlocks */#include <linux/delay.h>#ifdef HAVE_REALLY_SLOW_DMA_CONTROLLER#define dma_outb	outb_p#else#define dma_outb	outb#endif#define dma_inb		inb/* * NOTES about DMA transfers: * *  controller 1: channels 0-3, byte operations, ports 00-1F *  controller 2: channels 4-7, word operations, ports C0-DF * *  - ALL registers are 8 bits only, regardless of transfer size *  - channel 4 is not used - cascades 1 into 2. *  - channels 0-3 are byte - addresses/counts are for physical bytes *  - channels 5-7 are word - addresses/counts are for physical words *  - transfers must not cross physical 64K (0-3) or 128K (5-7) boundaries *  - transfer count loaded to registers is 1 less than actual count *  - controller 2 offsets are all even (2x offsets for controller 1) *  - page registers for 5-7 don't use data bit 0, represent 128K pages *  - page registers for 0-3 use bit 0, represent 64K pages * * DMA transfers are limited to the lower 16MB of _physical_ memory. * Note that addresses loaded into registers must be _physical_ addresses, * not logical addresses (which may differ if paging is active). * *  Address mapping for channels 0-3: * *   A23 ... A16 A15 ... A8  A7 ... A0    (Physical addresses) *    |  ...  |   |  ... |   |  ... | *    |  ...  |   |  ... |   |  ... | *    |  ...  |   |  ... |   |  ... | *   P7  ...  P0  A7 ... A0  A7 ... A0 * |    Page    | Addr MSB | Addr LSB |   (DMA registers) * *  Address mapping for channels 5-7: * *   A23 ... A17 A16 A15 ... A9 A8 A7 ... A1 A0    (Physical addresses) *    |  ...  |   \   \   ... \  \  \  ... \  \ *    |  ...  |    \   \   ... \  \  \  ... \  (not used) *    |  ...  |     \   \   ... \  \  \  ... \ *   P7  ...  P1 (0) A7 A6  ... A0 A7 A6 ... A0 * |      Page      |  Addr MSB   |  Addr LSB  |   (DMA registers) * * Again, channels 5-7 transfer _physical_ words (16 bits), so addresses * and counts _must_ be word-aligned (the lowest address bit is _ignored_ at * the hardware level, so odd-byte transfers aren't possible). * * Transfer count (_not # bytes_) is limited to 64K, represented as actual * count - 1 : 64K => 0xFFFF, 1 => 0x0000.  Thus, count is always 1 or more, * and up to 128K bytes may be transferred on channels 5-7 in one operation. * */#ifndef CONFIG_GENERIC_ISA_DMA_SUPPORT_BROKEN#define MAX_DMA_CHANNELS	8#endif/* * The maximum address in KSEG0 that we can perform a DMA transfer to on this * platform.  This describes only the PC style part of the DMA logic like on * Deskstations or Acer PICA but not the much more versatile DMA logic used * for the local devices on Acer PICA or Magnums. */#if defined(CONFIG_SGI_IP22) || defined(CONFIG_SGI_IP28)/* don't care; ISA bus master won't work, ISA slave DMA supports 32bit addr */#define MAX_DMA_ADDRESS		PAGE_OFFSET#else#define MAX_DMA_ADDRESS		(PAGE_OFFSET + 0x01000000)#endif#define MAX_DMA_PFN		PFN_DOWN(virt_to_phys((void *)MAX_DMA_ADDRESS))#ifndef MAX_DMA32_PFN#define MAX_DMA32_PFN		(1UL << (32 - PAGE_SHIFT))#endif/* 8237 DMA controllers */#define IO_DMA1_BASE	0x00	/* 8 bit slave DMA, channels 0..3 */#define IO_DMA2_BASE	0xC0	/* 16 bit master DMA, ch 4(=slave input)..7 *//* DMA controller registers */#define DMA1_CMD_REG		0x08	/* command register (w) */#define DMA1_STAT_REG		0x08	/* status register (r) */#define DMA1_REQ_REG            0x09    /* request register (w) */#define DMA1_MASK_REG		0x0A	/* single-channel mask (w) */#define DMA1_MODE_REG		0x0B	/* mode register (w) */#define DMA1_CLEAR_FF_REG	0x0C	/* clear pointer flip-flop (w) */#define DMA1_TEMP_REG           0x0D    /* Temporary Register (r) */#define DMA1_RESET_REG		0x0D	/* Master Clear (w) */#define DMA1_CLR_MASK_REG       0x0E    /* Clear Mask */#define DMA1_MASK_ALL_REG       0x0F    /* all-channels mask (w) */#define DMA2_CMD_REG		0xD0	/* command register (w) */#define DMA2_STAT_REG		0xD0	/* status register (r) */#define DMA2_REQ_REG            0xD2    /* request register (w) */#define DMA2_MASK_REG		0xD4	/* single-channel mask (w) */#define DMA2_MODE_REG		0xD6	/* mode register (w) */#define DMA2_CLEAR_FF_REG	0xD8	/* clear pointer flip-flop (w) */#define DMA2_TEMP_REG           0xDA    /* Temporary Register (r) */#define DMA2_RESET_REG		0xDA	/* Master Clear (w) */#define DMA2_CLR_MASK_REG       0xDC    /* Clear Mask */#define DMA2_MASK_ALL_REG       0xDE    /* all-channels mask (w) */#define DMA_ADDR_0              0x00    /* DMA address registers */#define DMA_ADDR_1              0x02#define DMA_ADDR_2              0x04#define DMA_ADDR_3              0x06#define DMA_ADDR_4              0xC0#define DMA_ADDR_5              0xC4#define DMA_ADDR_6              0xC8#define DMA_ADDR_7              0xCC#define DMA_CNT_0               0x01    /* DMA count registers */#define DMA_CNT_1               0x03#define DMA_CNT_2               0x05#define DMA_CNT_3               0x07#define DMA_CNT_4               0xC2#define DMA_CNT_5               0xC6#define DMA_CNT_6               0xCA#define DMA_CNT_7               0xCE#define DMA_PAGE_0              0x87    /* DMA page registers */#define DMA_PAGE_1              0x83#define DMA_PAGE_2              0x81#define DMA_PAGE_3              0x82#define DMA_PAGE_5              0x8B#define DMA_PAGE_6              0x89#define DMA_PAGE_7              0x8A#define DMA_MODE_READ	0x44	/* I/O to memory, no autoinit, increment, single mode */#define DMA_MODE_WRITE	0x48	/* memory to I/O, no autoinit, increment, single mode */#define DMA_MODE_CASCADE 0xC0   /* pass thru DREQ->HRQ, DACK<-HLDA only */#define DMA_AUTOINIT	0x10extern 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);}/* enable/disable a specific DMA channel */static __inline__ void enable_dma(unsigned int dmanr){	if (dmanr<=3)
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