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: Russell King <rmk+kernel@armlinux.org.uk>

diff --git a/arch/arm/mach-rpc/dma.c b/arch/arm/mach-rpc/dma.c
index 6140472..eeda808 100644 (file)
--- a/arch/arm/mach-rpc/dma.c
+++ b/arch/arm/mach-rpc/dma.c
@@ -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++) {