[PATCH v2 1/3] irqchip: dw-apb-ictl: always use use {readl|writel}_relaxed

Jisheng Zhang jszhang at marvell.com
Tue Nov 11 22:22:52 PST 2014


There's no DMA at all, the device type memory attribute can ensure the
operations order and relaxed version imply compiler barrier, so we are safe
to use relaxed version to improve the performance a bit.

Signed-off-by: Jisheng Zhang <jszhang at marvell.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth at gmail.com>
---
 drivers/irqchip/irq-dw-apb-ictl.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/irqchip/irq-dw-apb-ictl.c b/drivers/irqchip/irq-dw-apb-ictl.c
index 31e231e..fcc3385 100644
--- a/drivers/irqchip/irq-dw-apb-ictl.c
+++ b/drivers/irqchip/irq-dw-apb-ictl.c
@@ -94,16 +94,16 @@ static int __init dw_apb_ictl_init(struct device_node *np,
 	 */
 
 	/* mask and enable all interrupts */
-	writel(~0, iobase + APB_INT_MASK_L);
-	writel(~0, iobase + APB_INT_MASK_H);
-	writel(~0, iobase + APB_INT_ENABLE_L);
-	writel(~0, iobase + APB_INT_ENABLE_H);
+	writel_relaxed(~0, iobase + APB_INT_MASK_L);
+	writel_relaxed(~0, iobase + APB_INT_MASK_H);
+	writel_relaxed(~0, iobase + APB_INT_ENABLE_L);
+	writel_relaxed(~0, iobase + APB_INT_ENABLE_H);
 
-	reg = readl(iobase + APB_INT_ENABLE_H);
+	reg = readl_relaxed(iobase + APB_INT_ENABLE_H);
 	if (reg)
 		nrirqs = 32 + fls(reg);
 	else
-		nrirqs = fls(readl(iobase + APB_INT_ENABLE_L));
+		nrirqs = fls(readl_relaxed(iobase + APB_INT_ENABLE_L));
 
 	domain = irq_domain_add_linear(np, nrirqs,
 				       &irq_generic_chip_ops, NULL);
-- 
2.1.3




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