[ARM] pxa: stop and disable IRQ for each DMA channels at startup
Some broken bootloaders will leave the DMA channel state unclean, which
we should really initialize correctly here.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
diff --git a/arch/arm/mach-pxa/dma.c b/arch/arm/mach-pxa/dma.c
index b1514fb..7de17fc 100644
--- a/arch/arm/mach-pxa/dma.c
+++ b/arch/arm/mach-pxa/dma.c
@@ -121,6 +121,16 @@
if (dma_channels == NULL)
return -ENOMEM;
+ /* dma channel priorities on pxa2xx processors:
+ * ch 0 - 3, 16 - 19 <--> (0) DMA_PRIO_HIGH
+ * ch 4 - 7, 20 - 23 <--> (1) DMA_PRIO_MEDIUM
+ * ch 8 - 15, 24 - 31 <--> (2) DMA_PRIO_LOW
+ */
+ for (i = 0; i < num_ch; i++) {
+ DCSR(i) = 0;
+ dma_channels[i].prio = min((i & 0xf) >> 2, DMA_PRIO_LOW);
+ }
+
ret = request_irq(IRQ_DMA, dma_irq_handler, IRQF_DISABLED, "DMA", NULL);
if (ret) {
printk (KERN_CRIT "Wow! Can't register IRQ for DMA\n");
@@ -128,14 +138,6 @@
return ret;
}
- /* dma channel priorities on pxa2xx processors:
- * ch 0 - 3, 16 - 19 <--> (0) DMA_PRIO_HIGH
- * ch 4 - 7, 20 - 23 <--> (1) DMA_PRIO_MEDIUM
- * ch 8 - 15, 24 - 31 <--> (2) DMA_PRIO_LOW
- */
- for (i = 0; i < num_ch; i++)
- dma_channels[i].prio = min((i & 0xf) >> 2, DMA_PRIO_LOW);
-
num_dma_channels = num_ch;
return 0;
}
