Commit 8194468f authored by Russell King's avatar Russell King
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ARM: riscpc: dma: eliminate "cur_sg" scatterlist usage 



All we really need is the DMA address and size, we don't need the
baggage of a full scatterlist structure.

Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
parent ffd9a1ba

arch/arm/mach-rpc/dma.c

+15 −14
Original line number Diff line number Diff line
@@ -30,7 +30,8 @@ struct iomd_dma { 
	unsigned int		state;

	unsigned long		base;		/* Controller base address */

	int			irq;		/* Controller IRQ */

	struct scatterlist	cur_sg;		/* Current controller buffer */

	dma_addr_t		cur_addr;

	unsigned int		cur_len;

	dma_addr_t		dma_addr;

	unsigned int		dma_len;

};
@@ -53,13 +54,13 @@ typedef enum { 
#define CR	(IOMD_IO0CR - IOMD_IO0CURA)

#define ST	(IOMD_IO0ST - IOMD_IO0CURA)



static void iomd_get_next_sg(struct scatterlist *sg, struct iomd_dma *idma)

static void iomd_get_next_sg(struct iomd_dma *idma)

{

	unsigned long end, offset, flags = 0;



	if (idma->dma.sg) {

		sg->dma_address = idma->dma_addr;

		offset = sg->dma_address & ~PAGE_MASK;

		idma->cur_addr = idma->dma_addr;

		offset = idma->cur_addr & ~PAGE_MASK;



		end = offset + idma->dma_len;
@@ -69,7 +70,7 @@ static void iomd_get_next_sg(struct scatterlist *sg, struct iomd_dma *idma) 
		if (offset + TRANSFER_SIZE >= end)

			flags |= DMA_END_L;



		sg->length = end - TRANSFER_SIZE;

		idma->cur_len = end - TRANSFER_SIZE;



		idma->dma_len -= end - offset;

		idma->dma_addr += end - offset;
@@ -87,11 +88,11 @@ static void iomd_get_next_sg(struct scatterlist *sg, struct iomd_dma *idma) 
		}

	} else {

		flags = DMA_END_S | DMA_END_L;

		sg->dma_address = 0;

		sg->length = 0;

		idma->cur_addr = 0;

		idma->cur_len = 0;

	}



	sg->length |= flags;

	idma->cur_len |= flags;

}



static irqreturn_t iomd_dma_handle(int irq, void *dev_id)
@@ -107,26 +108,26 @@ static irqreturn_t iomd_dma_handle(int irq, void *dev_id) 
			return IRQ_HANDLED;



		if ((idma->state ^ status) & DMA_ST_AB)

			iomd_get_next_sg(&idma->cur_sg, idma);

			iomd_get_next_sg(idma);



		switch (status & (DMA_ST_OFL | DMA_ST_AB)) {

		case DMA_ST_OFL:			/* OIA */

		case DMA_ST_AB:				/* .IB */

			iomd_writel(idma->cur_sg.dma_address, base + CURA);

			iomd_writel(idma->cur_sg.length, base + ENDA);

			iomd_writel(idma->cur_addr, base + CURA);

			iomd_writel(idma->cur_len, base + ENDA);

			idma->state = DMA_ST_AB;

			break;



		case DMA_ST_OFL | DMA_ST_AB:		/* OIB */

		case 0:					/* .IA */

			iomd_writel(idma->cur_sg.dma_address, base + CURB);

			iomd_writel(idma->cur_sg.length, base + ENDB);

			iomd_writel(idma->cur_addr, base + CURB);

			iomd_writel(idma->cur_len, base + ENDB);

			idma->state = 0;

			break;

		}



		if (status & DMA_ST_OFL &&

		    idma->cur_sg.length == (DMA_END_S|DMA_END_L))

		    idma->cur_len == (DMA_END_S|DMA_END_L))

			break;

	} while (1);