summaryrefslogtreecommitdiffstats
path: root/include/asm-i386/mca_dma.h
diff options
context:
space:
mode:
authorRalf Baechle <ralf@linux-mips.org>1999-02-15 02:15:32 +0000
committerRalf Baechle <ralf@linux-mips.org>1999-02-15 02:15:32 +0000
commit86464aed71025541805e7b1515541aee89879e33 (patch)
treee01a457a4912a8553bc65524aa3125d51f29f810 /include/asm-i386/mca_dma.h
parent88f99939ecc6a95a79614574cb7d95ffccfc3466 (diff)
Merge with Linux 2.2.1.
Diffstat (limited to 'include/asm-i386/mca_dma.h')
-rw-r--r--include/asm-i386/mca_dma.h126
1 files changed, 126 insertions, 0 deletions
diff --git a/include/asm-i386/mca_dma.h b/include/asm-i386/mca_dma.h
new file mode 100644
index 000000000..791152f3d
--- /dev/null
+++ b/include/asm-i386/mca_dma.h
@@ -0,0 +1,126 @@
+#ifndef MCA_DMA_H
+#define MCA_DMA_H
+
+#include <asm/io.h>
+#include <linux/ioport.h>
+
+/*
+ * Microchannel specific DMA stuff. DMA on an MCA machine is fairly similar to
+ * standard PC dma, but it certainly has its quirks. DMA register addresses
+ * are in a different place and there are some added functions. Most of this
+ * should be pretty obvious on inspection. Note that the user must divide
+ * count by 2 when using 16-bit dma; that is not handled by these functions.
+ *
+ * Ramen Noodles are yummy.
+ *
+ * 1998 Tymm Twillman <tymm@computer.org>
+ */
+
+/*
+ * Registers that are used by the DMA controller; FN is the function register
+ * (tell the controller what to do) and EXE is the execution register (how
+ * to do it)
+ */
+
+#define MCA_DMA_REG_FN 0x18
+#define MCA_DMA_REG_EXE 0x1A
+
+/*
+ * Functions that the DMA controller can do
+ */
+
+#define MCA_DMA_FN_SET_IO 0x00
+#define MCA_DMA_FN_SET_ADDR 0x20
+#define MCA_DMA_FN_GET_ADDR 0x30
+#define MCA_DMA_FN_SET_COUNT 0x40
+#define MCA_DMA_FN_GET_COUNT 0x50
+#define MCA_DMA_FN_GET_STATUS 0x60
+#define MCA_DMA_FN_SET_MODE 0x70
+#define MCA_DMA_FN_SET_ARBUS 0x80
+#define MCA_DMA_FN_MASK 0x90
+#define MCA_DMA_FN_RESET_MASK 0xA0
+#define MCA_DMA_FN_MASTER_CLEAR 0xD0
+
+/*
+ * Modes (used by setting MCA_DMA_FN_MODE in the function register)
+ *
+ * Note that the MODE_READ is read from memory (write to device), and
+ * MODE_WRITE is vice-versa.
+ */
+
+#define MCA_DMA_MODE_XFER 0x04 /* read by default */
+#define MCA_DMA_MODE_READ 0x04 /* same as XFER */
+#define MCA_DMA_MODE_WRITE 0x08 /* OR with MODE_XFER to use */
+#define MCA_DMA_MODE_IO 0x01 /* DMA from IO register */
+#define MCA_DMA_MODE_16 0x40 /* 16 bit xfers */
+
+
+
+static __inline__ void mca_enable_dma(unsigned int dmanr)
+{
+ outb(MCA_DMA_FN_RESET_MASK | dmanr, MCA_DMA_REG_FN);
+}
+
+static __inline__ void mca_disable_dma(unsigned int dmanr)
+{
+ outb(MCA_DMA_FN_MASK | dmanr, MCA_DMA_REG_FN);
+}
+
+static __inline__ void mca_set_dma_addr(unsigned int dmanr, unsigned int a)
+{
+ outb(MCA_DMA_FN_SET_ADDR | dmanr, MCA_DMA_REG_FN);
+ outb(a & 0xff, MCA_DMA_REG_EXE);
+ outb((a >> 8) & 0xff, MCA_DMA_REG_EXE);
+ outb((a >> 16) & 0xff, MCA_DMA_REG_EXE);
+}
+
+static __inline__ unsigned int mca_get_dma_addr(unsigned int dmanr)
+{
+ unsigned int addr;
+
+ outb(MCA_DMA_FN_GET_ADDR | dmanr, MCA_DMA_REG_FN);
+ addr = inb(MCA_DMA_REG_EXE);
+ addr |= inb(MCA_DMA_REG_EXE) << 8;
+ addr |= inb(MCA_DMA_REG_EXE) << 16;
+
+ return addr;
+}
+
+static __inline__ void mca_set_dma_count(unsigned int dmanr, unsigned int count)
+{
+ count--; /* transfers one more than count -- correct for this */
+
+ outb(MCA_DMA_FN_SET_COUNT | dmanr, MCA_DMA_REG_FN);
+ outb(count & 0xff, MCA_DMA_REG_EXE);
+ outb((count >> 8) & 0xff, MCA_DMA_REG_EXE);
+}
+
+static __inline__ unsigned int mca_get_dma_residue(unsigned int dmanr)
+{
+ unsigned short count;
+
+ outb(MCA_DMA_FN_GET_COUNT | dmanr, MCA_DMA_REG_FN);
+ count = 1 + inb(MCA_DMA_REG_EXE);
+ count += inb(MCA_DMA_REG_EXE) << 8;
+
+ return count;
+}
+
+static __inline__ void mca_set_dma_io(unsigned int dmanr, unsigned int io_addr)
+{
+ /*
+ * DMA from a port address -- set the io address
+ */
+
+ outb(MCA_DMA_FN_SET_IO | dmanr, MCA_DMA_REG_FN);
+ outb(io_addr & 0xff, MCA_DMA_REG_EXE);
+ outb((io_addr >> 8) & 0xff, MCA_DMA_REG_EXE);
+}
+
+static __inline__ void mca_set_dma_mode(unsigned int dmanr, unsigned int mode)
+{
+ outb(MCA_DMA_FN_SET_MODE | dmanr, MCA_DMA_REG_FN);
+ outb(mode, MCA_DMA_REG_EXE);
+}
+
+#endif MCA_DMA_H