diff mbox series

[v2] PCI: mediatek: Clear interrupt status before dispatching handler

Message ID 20220210012125.6420-1-qizhong.cheng@mediatek.com (mailing list archive)
State New, archived
Headers show
Series [v2] PCI: mediatek: Clear interrupt status before dispatching handler | expand

Commit Message

qizhong cheng Feb. 10, 2022, 1:21 a.m. UTC
We found a failure when used iperf tool for wifi performance testing,
there are some MSIs received while clearing the interrupt status,
these MSIs cannot be serviced.

The interrupt status can be cleared even the MSI status still remaining,
as an edge-triggered interrupts, its interrupt status should be cleared
before dispatching to the handler of device.

Signed-off-by: qizhong cheng <qizhong.cheng@mediatek.com>
---
v2:
 - Update the subject line.
 - Improve the commit log and code comments.

 drivers/pci/controller/pcie-mediatek.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

Comments

Greg Kroah-Hartman Feb. 10, 2022, 6:50 a.m. UTC | #1
On Thu, Feb 10, 2022 at 09:21:25AM +0800, qizhong cheng wrote:
> We found a failure when used iperf tool for wifi performance testing,
> there are some MSIs received while clearing the interrupt status,
> these MSIs cannot be serviced.
> 
> The interrupt status can be cleared even the MSI status still remaining,
> as an edge-triggered interrupts, its interrupt status should be cleared
> before dispatching to the handler of device.
> 
> Signed-off-by: qizhong cheng <qizhong.cheng@mediatek.com>
> ---
> v2:
>  - Update the subject line.
>  - Improve the commit log and code comments.
> 
>  drivers/pci/controller/pcie-mediatek.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>
AngeloGioacchino Del Regno Feb. 10, 2022, 2:31 p.m. UTC | #2
Il 10/02/22 02:21, qizhong cheng ha scritto:
> We found a failure when used iperf tool for wifi performance testing,
> there are some MSIs received while clearing the interrupt status,
> these MSIs cannot be serviced.
> 
> The interrupt status can be cleared even the MSI status still remaining,
> as an edge-triggered interrupts, its interrupt status should be cleared
> before dispatching to the handler of device.
> 
> Signed-off-by: qizhong cheng <qizhong.cheng@mediatek.com>

Hello Qizhong,

This commit is fixing an issue, which means that you *have to* add a proper
Fixes tag.

I believe that this is fixing commit
43e6409db64d ("PCI: mediatek: Add MSI support for MT2712 and MT7622").

Please add the tag and send a v3, after which:
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>


> ---
> v2:
>   - Update the subject line.
>   - Improve the commit log and code comments.
> 
>   drivers/pci/controller/pcie-mediatek.c | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
> index 2f3f974977a3..2856d74b2513 100644
> --- a/drivers/pci/controller/pcie-mediatek.c
> +++ b/drivers/pci/controller/pcie-mediatek.c
> @@ -624,12 +624,17 @@ static void mtk_pcie_intr_handler(struct irq_desc *desc)
>   		if (status & MSI_STATUS){
>   			unsigned long imsi_status;
>   
> +			/*
> +			 * The interrupt status can be cleared even the MSI
> +			 * status still remaining, hence as an edge-triggered
> +			 * interrupts, its interrupt status should be cleared
> +			 * before dispatching handler.
> +			 */
> +			writel(MSI_STATUS, port->base + PCIE_INT_STATUS);
>   			while ((imsi_status = readl(port->base + PCIE_IMSI_STATUS))) {
>   				for_each_set_bit(bit, &imsi_status, MTK_MSI_IRQS_NUM)
>   					generic_handle_domain_irq(port->inner_domain, bit);
>   			}
> -			/* Clear MSI interrupt status */
> -			writel(MSI_STATUS, port->base + PCIE_INT_STATUS);
>   		}
>   	}
>   
>
qizhong cheng Feb. 11, 2022, 6:50 a.m. UTC | #3
Hi AngeloGioacchino & Greg KH,

On Thu, 2022-02-10 at 15:31 +0100, AngeloGioacchino Del Regno wrote:
> Il 10/02/22 02:21, qizhong cheng ha scritto:
> > We found a failure when used iperf tool for wifi performance
> > testing,
> > there are some MSIs received while clearing the interrupt status,
> > these MSIs cannot be serviced.
> > 
> > The interrupt status can be cleared even the MSI status still
> > remaining,
> > as an edge-triggered interrupts, its interrupt status should be
> > cleared
> > before dispatching to the handler of device.
> > 
> > Signed-off-by: qizhong cheng <qizhong.cheng@mediatek.com>
> 
> Hello Qizhong,
> 
> This commit is fixing an issue, which means that you *have to* add a
> proper
> Fixes tag.
> 
> I believe that this is fixing commit
> 43e6409db64d ("PCI: mediatek: Add MSI support for MT2712 and
> MT7622").
> 
> Please add the tag and send a v3, after which:
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> 

Thanks for your reviews and suggestions.
I will fix it in the next v3 version.

> 
> > ---
> > v2:
> >   - Update the subject line.
> >   - Improve the commit log and code comments.
> > 
> >   drivers/pci/controller/pcie-mediatek.c | 9 +++++++--
> >   1 file changed, 7 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/pci/controller/pcie-mediatek.c
> > b/drivers/pci/controller/pcie-mediatek.c
> > index 2f3f974977a3..2856d74b2513 100644
> > --- a/drivers/pci/controller/pcie-mediatek.c
> > +++ b/drivers/pci/controller/pcie-mediatek.c
> > @@ -624,12 +624,17 @@ static void mtk_pcie_intr_handler(struct
> > irq_desc *desc)
> >   		if (status & MSI_STATUS){
> >   			unsigned long imsi_status;
> >   
> > +			/*
> > +			 * The interrupt status can be cleared even the
> > MSI
> > +			 * status still remaining, hence as an edge-
> > triggered
> > +			 * interrupts, its interrupt status should be
> > cleared
> > +			 * before dispatching handler.
> > +			 */
> > +			writel(MSI_STATUS, port->base +
> > PCIE_INT_STATUS);
> >   			while ((imsi_status = readl(port->base +
> > PCIE_IMSI_STATUS))) {
> >   				for_each_set_bit(bit, &imsi_status,
> > MTK_MSI_IRQS_NUM)
> >   					generic_handle_domain_irq(port-
> > >inner_domain, bit);
> >   			}
> > -			/* Clear MSI interrupt status */
> > -			writel(MSI_STATUS, port->base +
> > PCIE_INT_STATUS);
> >   		}
> >   	}
> >   
> > 
> 
>
diff mbox series

Patch

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index 2f3f974977a3..2856d74b2513 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -624,12 +624,17 @@  static void mtk_pcie_intr_handler(struct irq_desc *desc)
 		if (status & MSI_STATUS){
 			unsigned long imsi_status;
 
+			/*
+			 * The interrupt status can be cleared even the MSI
+			 * status still remaining, hence as an edge-triggered
+			 * interrupts, its interrupt status should be cleared
+			 * before dispatching handler.
+			 */
+			writel(MSI_STATUS, port->base + PCIE_INT_STATUS);
 			while ((imsi_status = readl(port->base + PCIE_IMSI_STATUS))) {
 				for_each_set_bit(bit, &imsi_status, MTK_MSI_IRQS_NUM)
 					generic_handle_domain_irq(port->inner_domain, bit);
 			}
-			/* Clear MSI interrupt status */
-			writel(MSI_STATUS, port->base + PCIE_INT_STATUS);
 		}
 	}