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SAMA5 DMA: Address of next descriptor in list is a physical address

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This commit is contained in:
Gregory Nutt 2013-12-03 09:48:13 -06:00
parent 8ad33030d3
commit d125a28b0d
1 changed files with 13 additions and 6 deletions
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19
arch/arm/src/sama5/sam_dmac.c
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@ -1470,7 +1470,7 @@ static void sam_freelinklist(struct sam_dmach_s *dmach)
{
struct sam_dmac_s *dmac = sam_controller(dmach);
struct dma_linklist_s *desc;
struct dma_linklist_s *dscr;
uintptr_t paddr;
/* Get the head of the link list and detach the link list from the DMA
* channel
@ -1480,15 +1480,22 @@ static void sam_freelinklist(struct sam_dmach_s *dmach)
dmach->llhead = NULL;
dmach->lltail = NULL;
/* Reset each descriptor in the link list (thereby freeing them) */
while (desc != NULL)
{
dscr = (struct dma_linklist_s *)desc->dscr;
/* Get the physical address of the next desriptor in the list */
paddr = desc->dscr;
DEBUGASSERT(desc->saddr != 0);
/* Free the descriptor by simply nullifying it */
memset(desc, 0, sizeof(struct dma_linklist_s));
sam_givedsem(dmac);
desc = dscr;
/* Get the virtual address of the next descriptor in the list */
desc = (struct dma_linklist_s *)sam_virtramaddr(paddr);
}
}
@ -1644,7 +1651,7 @@ static inline int sam_single(struct sam_dmach_s *dmach)
sam_putdmac(dmac, DMAC_CHER_ENA(dmach->chan), SAM_DMAC_CHER_OFFSET);
/* The DMA has been started. Once the transfer completes, hardware sets
* the interrupts and disables the channel. We will received buffer
* the interrupts and disables the channel. We will receive buffer
* complete and transfer complete interrupts.
*
* Enable error, buffer complete and transfer complete interrupts.