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							- /*
 
-  * 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	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);
 
- }
 
- /* enable/disable a specific DMA channel */
 
- static __inline__ void enable_dma(unsigned int dmanr)
 
- {
 
- 	if (dmanr<=3)
 
- 		dma_outb(dmanr,  DMA1_MASK_REG);
 
- 	else
 
- 		dma_outb(dmanr & 3,  DMA2_MASK_REG);
 
- }
 
- static __inline__ void disable_dma(unsigned int dmanr)
 
- {
 
- 	if (dmanr<=3)
 
- 		dma_outb(dmanr | 4,  DMA1_MASK_REG);
 
- 	else
 
- 		dma_outb((dmanr & 3) | 4,  DMA2_MASK_REG);
 
- }
 
- /* Clear the 'DMA Pointer Flip Flop'.
 
-  * Write 0 for LSB/MSB, 1 for MSB/LSB access.
 
-  * Use this once to initialize the FF to a known state.
 
-  * After that, keep track of it. :-)
 
-  * --- In order to do that, the DMA routines below should ---
 
-  * --- only be used while holding the DMA lock ! ---
 
-  */
 
- static __inline__ void clear_dma_ff(unsigned int dmanr)
 
- {
 
- 	if (dmanr<=3)
 
- 		dma_outb(0,  DMA1_CLEAR_FF_REG);
 
- 	else
 
- 		dma_outb(0,  DMA2_CLEAR_FF_REG);
 
- }
 
- /* set mode (above) for a specific DMA channel */
 
- static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
 
- {
 
- 	if (dmanr<=3)
 
- 		dma_outb(mode | dmanr,  DMA1_MODE_REG);
 
- 	else
 
- 		dma_outb(mode | (dmanr&3),  DMA2_MODE_REG);
 
- }
 
- /* Set only the page register bits of the transfer address.
 
-  * This is used for successive transfers when we know the contents of
 
-  * the lower 16 bits of the DMA current address register, but a 64k boundary
 
-  * may have been crossed.
 
-  */
 
- static __inline__ void set_dma_page(unsigned int dmanr, char pagenr)
 
- {
 
 
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