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Date:   Mon, 27 Jun 2022 11:42:54 +0530
From:   Vinod Koul <vkoul@kernel.org>
To:     Jie Hai <haijie1@huawei.com>
Cc:     wangzhou1@hisilicon.com, dmaengine@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/8] dmaengine: hisilicon: Fix CQ head update
Message-ID: <YrlKZgC999AYMvXY@matsya>
References: <20220625074422.3479591-1-haijie1@huawei.com>
 <20220625074422.3479591-3-haijie1@huawei.com>
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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@huawei.com>
> ---
>  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