/* * 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. * Changes for ppc sound by Christoph Nadig */ #ifdef __KERNEL__ #include #include #include #include /* * Note: Adapted for PowerPC by Gary Thomas * Modified by Cort Dougan * * None of this really applies for Power Macintoshes. There is * basically just enough here to get kernel/dma.c to compile. * * There may be some comments or restrictions made here which are * not valid for the PReP platform. Take what you read * with a grain of salt. */ #ifndef _ASM_DMA_H #define _ASM_DMA_H #ifndef MAX_DMA_CHANNELS #define MAX_DMA_CHANNELS 8 #endif /* The maximum address that we can perform a DMA transfer to on this platform */ /* Doesn't really apply... */ #define MAX_DMA_ADDRESS 0xFFFFFFFF /* in arch/ppc/kernel/setup.c -- Cort */ extern unsigned long DMA_MODE_WRITE, DMA_MODE_READ; extern unsigned long ISA_DMA_THRESHOLD; #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 * * On PReP, DMA transfers are limited to the lower 16MB of _physical_ memory. * On CHRP, the W83C553F (and VLSI Tollgate?) support full 32 bit addressing. * 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. * */ /* see prep_setup_arch() for detailed informations */ #if defined(CONFIG_SOUND_CS4232) && defined(CONFIG_ALL_PPC) extern long ppc_cs4232_dma, ppc_cs4232_dma2; #define SND_DMA1 ppc_cs4232_dma #define SND_DMA2 ppc_cs4232_dma2 #else #define SND_DMA1 -1 #define SND_DMA2 -1 #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_LO_PAGE_0 0x87 /* DMA page registers */ #define DMA_LO_PAGE_1 0x83 #define DMA_LO_PAGE_2 0x81 #define DMA_LO_PAGE_3 0x82 #define DMA_LO_PAGE_5 0x8B #define DMA_LO_PAGE_6 0x89 #define DMA_LO_PAGE_7 0x8A #define DMA_HI_PAGE_0 0x487 /* DMA page registers */ #define DMA_HI_PAGE_1 0x483 #define DMA_HI_PAGE_2 0x481 #define DMA_HI_PAGE_3 0x482 #define DMA_HI_PAGE_5 0x48B #define DMA_HI_PAGE_6 0x489 #define DMA_HI_PAGE_7 0x48A #define DMA1_EXT_REG 0x40B #define DMA2_EXT_REG 0x4D6 #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) { unsigned char ucDmaCmd=0x00; if (dmanr != 4) { dma_outb(0, DMA2_MASK_REG); /* This may not be enabled */ dma_outb(ucDmaCmd, DMA2_CMD_REG); /* Enable group */ } if (dmanr <= 3) { dma_outb(dmanr, DMA1_MASK_REG); dma_outb(ucDmaCmd, DMA1_CMD_REG); /* Enable group */ } 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 interrupts are disabled! --- */ 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, int pagenr) { switch(dmanr) { case 0: dma_outb(pagenr, DMA_LO_PAGE_0); dma_outb(pagenr >> 8, DMA_HI_PAGE_0); break; case 1: dma_outb(pagenr, DMA_LO_PAGE_1); dma_outb(pagenr >> 8, DMA_HI_PAGE_1); break; case 2: dma_outb(pagenr, DMA_LO_PAGE_2); dma_outb(pagenr >> 8, DMA_HI_PAGE_2); break; case 3: dma_outb(pagenr, DMA_LO_PAGE_3); dma_outb(pagenr >> 8, DMA_HI_PAGE_3); break; case 5: if (SND_DMA1 == 5 || SND_DMA2 == 5) dma_outb(pagenr, DMA_LO_PAGE_5); else dma_outb(pagenr & 0xfe, DMA_LO_PAGE_5); dma_outb(pagenr >> 8, DMA_HI_PAGE_5); break; case 6: if (SND_DMA1 == 6 || SND_DMA2 == 6) dma_outb(pagenr, DMA_LO_PAGE_6); else dma_outb(pagenr & 0xfe, DMA_LO_PAGE_6); dma_outb(pagenr >> 8, DMA_HI_PAGE_6); break; case 7: if (SND_DMA1 == 7 || SND_DMA2 == 7) dma_outb(pagenr, DMA_LO_PAGE_7); else dma_outb(pagenr & 0xfe, DMA_LO_PAGE_7); dma_outb(pagenr >> 8, DMA_HI_PAGE_7); break; } } /* Set transfer address & page bits for specific DMA channel. * Assumes dma flipflop is clear. */ static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int phys) { if (dmanr <= 3) { dma_outb(phys & 0xff, ((dmanr & 3) << 1) + IO_DMA1_BASE ); dma_outb((phys >> 8) & 0xff, ((dmanr & 3) << 1) + IO_DMA1_BASE); } else if (dmanr == SND_DMA1 || dmanr == SND_DMA2) { dma_outb(phys & 0xff, ((dmanr & 3) << 2) + IO_DMA2_BASE ); dma_outb((phys >> 8) & 0xff, ((dmanr & 3) << 2) + IO_DMA2_BASE); dma_outb((dmanr & 3), DMA2_EXT_REG); } else { dma_outb((phys >> 1) & 0xff, ((dmanr & 3) << 2) + IO_DMA2_BASE); dma_outb((phys >> 9) & 0xff, ((dmanr & 3) << 2) + IO_DMA2_BASE); } set_dma_page(dmanr, phys >> 16); } /* Set transfer size (max 64k for DMA1..3, 128k for DMA5..7) for * a specific DMA channel. * You must ensure the parameters are valid. * NOTE: from a manual: "the number of transfers is one more * than the initial word count"! This is taken into account. * Assumes dma flip-flop is clear. * NOTE 2: "count" represents _bytes_ and must be even for channels 5-7. */ static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count) { count--; if (dmanr <= 3) { dma_outb(count & 0xff, ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE); dma_outb((count >> 8) & 0xff, ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE); } else if (dmanr == SND_DMA1 || dmanr == SND_DMA2) { dma_outb( count & 0xff, ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE); dma_outb( (count >> 8) & 0xff, ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE); } else { dma_outb((count >> 1) & 0xff, ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE); dma_outb((count >> 9) & 0xff, ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE); } } /* 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. * * Assumes DMA flip-flop is clear. */ static __inline__ int get_dma_residue(unsigned int dmanr) { unsigned int io_port = (dmanr <= 3) ? ((dmanr & 3) << 1) + 1 + IO_DMA1_BASE : ((dmanr & 3) << 2) + 2 + IO_DMA2_BASE; /* using short to get 16-bit wrap around */ unsigned short count; count = 1 + dma_inb(io_port); count += dma_inb(io_port) << 8; return (dmanr <= 3 || dmanr == SND_DMA1 || dmanr == SND_DMA2) ? count : (count<<1); } /* These are in kernel/dma.c: */ /* reserve a DMA channel */ extern int request_dma(unsigned int dmanr, const char * device_id); /* release it again */ extern void free_dma(unsigned int dmanr); #ifdef CONFIG_PCI extern int isa_dma_bridge_buggy; #else #define isa_dma_bridge_buggy (0) #endif #endif /* _ASM_DMA_H */ #endif /* __KERNEL__ */