P4080 PCIe Adapter SDK User Guide Production Release

Freescale Semiconductor
int dma_ring_init(struct dma_ring *dring, struct dma_channel *dma_chan, itn count);
struct dma_ring {
};
u32 head;
u32 tail;
u32 free;
u32 count;
u8 *ring_mem;
u32 ring_memsize;
struct dma_channel *dma_chan;
struct dma_sw_desc *ring_base;
head – Head index to the DMA descriptor ring.
tail – Tail index to the DMA descriptor ring.
free – Index representing first free DMA descriptor
count – Maximum number of DMA descriptors in the DMA ring.
ring_mem – Pointer to the allocated physical memory for DMA ring
ring_memsize – Total memory of the DMA ring
dma_chan – CCSR reference to DMA channel
ring_base – Aligned start address from “ring_mem”
struct dma_channel {
u32 mr;
u32 sr;
u32 eclndar;
u32 clndar;
u32 satr;
u32 sar;
u32 datr;
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