RE: [PATCH 2/8] dmaengine: hisilicon: Fix CQ head update

[haijie]

Hi, Vinod,

This happens bacause I rearranged this patch without checking, it will be corrected in v2.

Thanks.

-----Original Message-----
From: Vinod Koul [mailto:vkoul@xxxxxxxxxx] 
Sent: Monday, June 27, 2022 2:13 PM
To: haijie <haijie1@xxxxxxxxxx>
Cc: Wangzhou (B) <wangzhou1@xxxxxxxxxxxxx>; dmaengine@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: [PATCH 2/8] dmaengine: hisilicon: Fix CQ head update

On 25-06-22, 15:44, Jie Hai wrote:
> After completion of data transfer of one or multiple descriptors, the 
> completion status and the current head pointer to submission queue are 
> written into the CQ and interrupt can be generated to inform the 
> software. In interrupt process CQ is read and cq_head is updated.
> 
> hisi_dma_irq updates cq_head only when the completion status is 
> success. When an abnormal interrupt reports, cq_head will not update 
> which will cause subsequent interrupt processes read the error CQ and 
> never report the correct status.
> 
> This patch updates cq_head whenever CQ is accessed.
> 
> Fixes: e9f08b65250d ("dmaengine: hisilicon: Add Kunpeng DMA engine 
> support")
> 

No need for blank line
> Signed-off-by: Jie Hai <haijie1@xxxxxxxxxx>
> ---
>  drivers/dma/hisi_dma.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/dma/hisi_dma.c b/drivers/dma/hisi_dma.c index 
> 98bc488893cc..0a0f8a4d168a 100644
> --- a/drivers/dma/hisi_dma.c
> +++ b/drivers/dma/hisi_dma.c
> @@ -436,12 +436,11 @@ static irqreturn_t hisi_dma_irq(int irq, void *data)
>  	desc = chan->desc;
>  	cqe = chan->cq + chan->cq_head;
>  	if (desc) {
> +		chan->cq_head = (chan->cq_head + 1) %
> +				hdma_dev->chan_depth;
> +		hisi_dma_chan_write(q_base, HISI_DMA_Q_CQ_HEAD_PTR,

q_base?

--
~Vinod