Commit 26a55226 authored by Eric Miao's avatar Eric Miao
Browse files

[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: default avatarEric Miao <eric.miao@marvell.com>
parent b6729deb

arch/arm/mach-pxa/dma.c

+10 −8
Original line number Diff line number Diff line
@@ -121,20 +121,22 @@ int __init pxa_init_dma(int num_ch) 
	if (dma_channels == NULL)

		return -ENOMEM;



	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");

		kfree(dma_channels);

		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++)

	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");

		kfree(dma_channels);

		return ret;

	}



	num_dma_channels = num_ch;

	return 0;