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-rw-r--r--arch/arm/include/asm/dma.h143
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/arm/include/asm/dma.h b/arch/arm/include/asm/dma.h
new file mode 100644
index 000000000000..9f2c5305c260
--- /dev/null
+++ b/arch/arm/include/asm/dma.h
@@ -0,0 +1,143 @@
+#ifndef __ASM_ARM_DMA_H
+#define __ASM_ARM_DMA_H
+
+typedef unsigned int dmach_t;
+
+#include <linux/spinlock.h>
+#include <asm/system.h>
+#include <asm/scatterlist.h>
+#include <asm/arch/dma.h>
+
+/*
+ * This is the maximum virtual address which can be DMA'd from.
+ */
+#ifndef MAX_DMA_ADDRESS
+#define MAX_DMA_ADDRESS 0xffffffff
+#endif
+
+/*
+ * DMA modes
+ */
+typedef unsigned int dmamode_t;
+
+#define DMA_MODE_MASK 3
+
+#define DMA_MODE_READ 0
+#define DMA_MODE_WRITE 1
+#define DMA_MODE_CASCADE 2
+#define DMA_AUTOINIT 4
+
+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);
+}
+
+/* Clear the 'DMA Pointer Flip Flop'.
+ * Write 0 for LSB/MSB, 1 for MSB/LSB access.
+ */
+#define clear_dma_ff(channel)
+
+/* Set only the page register bits of the transfer address.
+ *
+ * NOTE: This is an architecture specific function, and should
+ * be hidden from the drivers
+ */
+extern void set_dma_page(dmach_t channel, char pagenr);
+
+/* Request a DMA channel
+ *
+ * Some architectures may need to do allocate an interrupt
+ */
+extern int request_dma(dmach_t channel, const char * device_id);
+
+/* Free a DMA channel
+ *
+ * Some architectures may need to do free an interrupt
+ */
+extern void free_dma(dmach_t channel);
+
+/* Enable DMA for this channel
+ *
+ * On some architectures, this may have other side effects like
+ * enabling an interrupt and setting the DMA registers.
+ */
+extern void enable_dma(dmach_t channel);
+
+/* Disable DMA for this channel
+ *
+ * On some architectures, this may have other side effects like
+ * disabling an interrupt or whatever.
+ */
+extern void disable_dma(dmach_t channel);
+
+/* Test whether the specified channel has an active DMA transfer
+ */
+extern int dma_channel_active(dmach_t channel);
+
+/* Set the DMA scatter gather list for this channel
+ *
+ * This should not be called if a DMA channel is enabled,
+ * especially since some DMA architectures don't update the
+ * DMA address immediately, but defer it to the enable_dma().
+ */
+extern void set_dma_sg(dmach_t channel, struct scatterlist *sg, int nr_sg);
+
+/* Set the DMA address for this channel
+ *
+ * This should not be called if a DMA channel is enabled,
+ * especially since some DMA architectures don't update the
+ * DMA address immediately, but defer it to the enable_dma().
+ */
+extern void __set_dma_addr(dmach_t channel, void *addr);
+#define set_dma_addr(channel, addr) \
+ __set_dma_addr(channel, bus_to_virt(addr))
+
+/* Set the DMA byte count for this channel
+ *
+ * This should not be called if a DMA channel is enabled,
+ * especially since some DMA architectures don't update the
+ * DMA count immediately, but defer it to the enable_dma().
+ */
+extern void set_dma_count(dmach_t channel, unsigned long count);
+
+/* Set the transfer direction for this channel
+ *
+ * This should not be called if a DMA channel is enabled,
+ * especially since some DMA architectures don't update the
+ * DMA transfer direction immediately, but defer it to the
+ * enable_dma().
+ */
+extern void set_dma_mode(dmach_t channel, dmamode_t mode);
+
+/* Set the transfer speed for this channel
+ */
+extern void set_dma_speed(dmach_t channel, int cycle_ns);
+
+/* 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.
+ */
+extern int get_dma_residue(dmach_t channel);
+
+#ifndef NO_DMA
+#define NO_DMA 255
+#endif
+
+#ifdef CONFIG_PCI
+extern int isa_dma_bridge_buggy;
+#else
+#define isa_dma_bridge_buggy (0)
+#endif
+
+#endif /* _ARM_DMA_H */
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