[Sound-open-firmware] [PATCH] cnl: gp-dma: fix gp-dma dead loop issue

[Liam Girdwood]

On Wed, 2018-02-28 at 16:52 +0800, Rander Wang wrote:
> In irq function, two dma would be checked which one is
> the interrupted one, so get it after check.
> 
> Signed-off-by: Rander Wang <rander.wang at intel.com>
> ---
>  src/drivers/dw-dma.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/src/drivers/dw-dma.c b/src/drivers/dw-dma.c
> index be19e12..6fd46e0 100644
> --- a/src/drivers/dw-dma.c
> +++ b/src/drivers/dw-dma.c
> @@ -1034,7 +1034,7 @@ static int dw_dma_probe(struct dma *dma)
>  static void dw_dma_irq_handler(void *data)
>  {
>  	struct dma *dma = (struct dma *)data;
> -	struct dma_pdata *p = dma_get_drvdata(dma);
> +	struct dma_pdata *p;
>  	struct dma_sg_elem next;
>  	uint32_t status_tfr = 0;
>  	uint32_t status_block = 0;
> @@ -1058,6 +1058,7 @@ static void dw_dma_irq_handler(void *data)
>  	}
>  
>  	tracev_dma("DIr");
> +	p = dma_get_drvdata(dma);
>  
>  	/* get the source of our IRQ. */
>  	status_block = dw_read(dma, DW_STATUS_BLOCK);


Iiuc, the IRQ for both DMACs on CNL is shared ? and we determine which
DMAC has the IRQ by reading each status register above ?

If so, this fails when both DMACs have IRQs at the same time.

Please do something like :-

dw_dma_irq_handler_cnl()
{
	dma = dmac0;

	/* read status for DMAC0 */
	status_intr = dw_read(dma, DW_INTR_STATUS);
	if (status_intr)
		dw_dma_irq_handler(dma);

	dma = dmac1;

	/* read status for DMAC1 */
	status_intr = dw_read(dma, DW_INTR_STATUS);
	if (status_intr)
		dw_dma_irq_handler(dma);
}

Liam