Commit 090a37ce authored by Russell King's avatar Russell King
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ARM: riscpc: dma: use __iomem pointers for writing DMA 



Use __iomem pointers for efficiency to write the DMA registers.
This avoids the compiler emitting several instructions for each access
to calculate the register address.

Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
parent e659587c

arch/arm/mach-rpc/dma.c

+17 −17
Original line number Diff line number Diff line
@@ -27,9 +27,9 @@ 


struct iomd_dma {

	struct dma_struct	dma;

	unsigned int		state;

	unsigned long		base;		/* Controller base address */

	void __iomem		*base;		/* Controller base address */

	int			irq;		/* Controller IRQ */

	unsigned int		state;

	dma_addr_t		cur_addr;

	unsigned int		cur_len;

	dma_addr_t		dma_addr;
@@ -98,12 +98,12 @@ static void iomd_get_next_sg(struct iomd_dma *idma) 
static irqreturn_t iomd_dma_handle(int irq, void *dev_id)

{

	struct iomd_dma *idma = dev_id;

	unsigned long base = idma->base;

	void __iomem *base = idma->base;

	unsigned int state = idma->state;

	unsigned int status, cur, end;



	do {

		status = iomd_readb(base + ST);

		status = readb(base + ST);

		if (!(status & DMA_ST_INT))

			goto out;
@@ -119,8 +119,8 @@ static irqreturn_t iomd_dma_handle(int irq, void *dev_id) 
			cur = CURB;

			end = ENDB;

		}

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

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

		writel(idma->cur_addr, base + cur);

		writel(idma->cur_len, base + end);



		if (status & DMA_ST_OFL &&

		    idma->cur_len == (DMA_END_S|DMA_END_L))
@@ -152,7 +152,7 @@ static void iomd_free_dma(unsigned int chan, dma_t *dma) 
static void iomd_enable_dma(unsigned int chan, dma_t *dma)

{

	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);

	unsigned long dma_base = idma->base;

	void __iomem *base = idma->base;

	unsigned int ctrl = TRANSFER_SIZE | DMA_CR_E;



	if (idma->dma.invalid) {
@@ -175,27 +175,27 @@ static void iomd_enable_dma(unsigned int chan, dma_t *dma) 
		idma->dma_addr = idma->dma.sg->dma_address;

		idma->dma_len = idma->dma.sg->length;



		iomd_writeb(DMA_CR_C, dma_base + CR);

		writeb(DMA_CR_C, base + CR);

		idma->state = DMA_ST_AB;

	}



	if (idma->dma.dma_mode == DMA_MODE_READ)

		ctrl |= DMA_CR_D;



	iomd_writeb(ctrl, dma_base + CR);

	writeb(ctrl, base + CR);

	enable_irq(idma->irq);

}



static void iomd_disable_dma(unsigned int chan, dma_t *dma)

{

	struct iomd_dma *idma = container_of(dma, struct iomd_dma, dma);

	unsigned long dma_base = idma->base;

	void __iomem *base = idma->base;

	unsigned long flags;



	local_irq_save(flags);

	if (idma->state != ~DMA_ST_AB)

		disable_irq(idma->irq);

	iomd_writeb(0, dma_base + CR);

	writeb(0, base + CR);

	local_irq_restore(flags);

}
@@ -358,17 +358,17 @@ static int __init rpc_dma_init(void) 
	 */

	iomd_writeb(DMA_EXT_IO3|DMA_EXT_IO2, IOMD_DMAEXT);



	iomd_dma[DMA_0].base	= IOMD_IO0CURA;

	iomd_dma[DMA_0].base	= IOMD_BASE + IOMD_IO0CURA;

	iomd_dma[DMA_0].irq	= IRQ_DMA0;

	iomd_dma[DMA_1].base	= IOMD_IO1CURA;

	iomd_dma[DMA_1].base	= IOMD_BASE + IOMD_IO1CURA;

	iomd_dma[DMA_1].irq	= IRQ_DMA1;

	iomd_dma[DMA_2].base	= IOMD_IO2CURA;

	iomd_dma[DMA_2].base	= IOMD_BASE + IOMD_IO2CURA;

	iomd_dma[DMA_2].irq	= IRQ_DMA2;

	iomd_dma[DMA_3].base	= IOMD_IO3CURA;

	iomd_dma[DMA_3].base	= IOMD_BASE + IOMD_IO3CURA;

	iomd_dma[DMA_3].irq	= IRQ_DMA3;

	iomd_dma[DMA_S0].base	= IOMD_SD0CURA;

	iomd_dma[DMA_S0].base	= IOMD_BASE + IOMD_SD0CURA;

	iomd_dma[DMA_S0].irq	= IRQ_DMAS0;

	iomd_dma[DMA_S1].base	= IOMD_SD1CURA;

	iomd_dma[DMA_S1].base	= IOMD_BASE + IOMD_SD1CURA;

	iomd_dma[DMA_S1].irq	= IRQ_DMAS1;



	for (i = DMA_0; i <= DMA_S1; i++) {