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path: root/src/drivers/pc80/pc/isa-dma.c
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Diffstat (limited to 'src/drivers/pc80/pc/isa-dma.c')
-rw-r--r--src/drivers/pc80/pc/isa-dma.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/src/drivers/pc80/pc/isa-dma.c b/src/drivers/pc80/pc/isa-dma.c
new file mode 100644
index 0000000000..b64f125f3a
--- /dev/null
+++ b/src/drivers/pc80/pc/isa-dma.c
@@ -0,0 +1,44 @@
+#include <arch/io.h>
+#include <pc80/isa-dma.h>
+
+/* 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_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
+
+
+void isa_dma_init(void)
+{
+ /* slave at 0x00 - 0x0f */
+ /* master at 0xc0 - 0xdf */
+ /* 0x80 - 0x8f DMA page registers */
+ /* DMA: 0x00, 0x02, 0x4, 0x06 base address for DMA channel */
+ outb(0, DMA1_RESET_REG);
+ outb(0, DMA2_RESET_REG);
+ outb(DMA_MODE_CASCADE, DMA2_MODE_REG);
+ outb(0, DMA2_MASK_REG);
+}