patch-2.3.41 linux/include/asm-m68k/apollodma.h

• Lines: 249
• Date: Fri Jan 28 08:04:58 2000
• Orig file: v2.3.40/linux/include/asm-m68k/apollodma.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.40/linux/include/asm-m68k/apollodma.h linux/include/asm-m68k/apollodma.h
@@ -0,0 +1,248 @@
+/* $Id: dma.h,v 1.7 1992/12/14 00:29:34 root Exp root $
+ * 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.
+ */
+
+#ifndef _ASM_APOLLO_DMA_H
+#define _ASM_APOLLO_DMA_H
+
+#include <asm/apollohw.h>		/* need byte IO */
+#include <asm/spinlock.h>	/* And spinlocks */
+#include <linux/delay.h>
+
+
+#define dma_outb(val,addr) (*((volatile unsigned char *)(addr+IO_BASE)) = (val))
+#define dma_inb(addr)	   (*((volatile unsigned char *)(addr+IO_BASE)))
+
+/*
+ * 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. 
+ *
+ */
+
+#define MAX_DMA_CHANNELS	8
+
+/* The maximum address that we can perform a DMA transfer to on this platform */#define MAX_DMA_ADDRESS      (PAGE_OFFSET+0x1000000)
+
+/* 8237 DMA controllers */
+#define IO_DMA1_BASE	0x10C00	/* 8 bit slave DMA, channels 0..3 */
+#define IO_DMA2_BASE	0x10D00	/* 16 bit master DMA, ch 4(=slave input)..7 */
+
+/* DMA controller registers */
+#define DMA1_CMD_REG		(IO_DMA1_BASE+0x08) /* command register (w) */
+#define DMA1_STAT_REG		(IO_DMA1_BASE+0x08) /* status register (r) */
+#define DMA1_REQ_REG            (IO_DMA1_BASE+0x09) /* request register (w) */
+#define DMA1_MASK_REG		(IO_DMA1_BASE+0x0A) /* single-channel mask (w) */
+#define DMA1_MODE_REG		(IO_DMA1_BASE+0x0B) /* mode register (w) */
+#define DMA1_CLEAR_FF_REG	(IO_DMA1_BASE+0x0C) /* clear pointer flip-flop (w) */
+#define DMA1_TEMP_REG           (IO_DMA1_BASE+0x0D) /* Temporary Register (r) */
+#define DMA1_RESET_REG		(IO_DMA1_BASE+0x0D) /* Master Clear (w) */
+#define DMA1_CLR_MASK_REG       (IO_DMA1_BASE+0x0E) /* Clear Mask */
+#define DMA1_MASK_ALL_REG       (IO_DMA1_BASE+0x0F) /* all-channels mask (w) */
+
+#define DMA2_CMD_REG		(IO_DMA2_BASE+0x10) /* command register (w) */
+#define DMA2_STAT_REG		(IO_DMA2_BASE+0x10) /* status register (r) */
+#define DMA2_REQ_REG            (IO_DMA2_BASE+0x12) /* request register (w) */
+#define DMA2_MASK_REG		(IO_DMA2_BASE+0x14) /* single-channel mask (w) */
+#define DMA2_MODE_REG		(IO_DMA2_BASE+0x16) /* mode register (w) */
+#define DMA2_CLEAR_FF_REG	(IO_DMA2_BASE+0x18) /* clear pointer flip-flop (w) */
+#define DMA2_TEMP_REG           (IO_DMA2_BASE+0x1A) /* Temporary Register (r) */
+#define DMA2_RESET_REG		(IO_DMA2_BASE+0x1A) /* Master Clear (w) */
+#define DMA2_CLR_MASK_REG       (IO_DMA2_BASE+0x1C) /* Clear Mask */
+#define DMA2_MASK_ALL_REG       (IO_DMA2_BASE+0x1E) /* all-channels mask (w) */
+
+#define DMA_ADDR_0              (IO_DMA1_BASE+0x00) /* DMA address registers */
+#define DMA_ADDR_1              (IO_DMA1_BASE+0x02)
+#define DMA_ADDR_2              (IO_DMA1_BASE+0x04)
+#define DMA_ADDR_3              (IO_DMA1_BASE+0x06)
+#define DMA_ADDR_4              (IO_DMA2_BASE+0x00)
+#define DMA_ADDR_5              (IO_DMA2_BASE+0x04)
+#define DMA_ADDR_6              (IO_DMA2_BASE+0x08)
+#define DMA_ADDR_7              (IO_DMA2_BASE+0x0C)
+
+#define DMA_CNT_0               (IO_DMA1_BASE+0x01)   /* DMA count registers */
+#define DMA_CNT_1               (IO_DMA1_BASE+0x03)
+#define DMA_CNT_2               (IO_DMA1_BASE+0x05)
+#define DMA_CNT_3               (IO_DMA1_BASE+0x07)
+#define DMA_CNT_4               (IO_DMA2_BASE+0x02)
+#define DMA_CNT_5               (IO_DMA2_BASE+0x06)
+#define DMA_CNT_6               (IO_DMA2_BASE+0x0A)
+#define DMA_CNT_7               (IO_DMA2_BASE+0x0E)
+
+#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
+
+#define DMA_8BIT 0
+#define DMA_16BIT 1
+#define DMA_BUSMASTER 2
+
+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 transfer address & page bits for specific DMA channel.
+ * Assumes dma flipflop is clear.
+ */
+static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
+{
+	if (dmanr <= 3)  {
+	    dma_outb( a & 0xff, ((dmanr&3)<<1) + IO_DMA1_BASE );
+            dma_outb( (a>>8) & 0xff, ((dmanr&3)<<1) + IO_DMA1_BASE );
+	}  else  {
+	    dma_outb( (a>>1) & 0xff, ((dmanr&3)<<2) + IO_DMA2_BASE );
+	    dma_outb( (a>>9) & 0xff, ((dmanr&3)<<2) + IO_DMA2_BASE );
+	}
+}
+
+
+/* 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 {
+	    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)? count : (count<<1);
+}
+
+
+/* These are in kernel/dma.c: */
+extern int request_dma(unsigned int dmanr, const char * device_id);	/* reserve a DMA channel */
+extern void free_dma(unsigned int dmanr);	/* release it again */
+
+/* These are in arch/m68k/apollo/dma.c: */
+extern unsigned short dma_map_page(unsigned long phys_addr,int count,int type);
+extern void dma_unmap_page(unsigned short dma_addr);
+
+#endif /* _ASM_APOLLO_DMA_H */