RE: [PATCHv2 10/25] PCI: mobiveil: fix the INTx process error

["M.h. Lian" <minghuan.lian@nxp.com>]

reviewed-by: Minghuan Lian <Minghuan.Lian@nxp.com>

> -----Original Message-----
> From: Z.q. Hou
> Sent: Tuesday, November 20, 2018 5:27 PM
> To: linux-pci@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> devicetree@vger.kernel.org; linux-kernel@vger.kernel.org;
> bhelgaas@google.com; robh+dt@kernel.org; mark.rutland@arm.com;
> l.subrahmanya@mobiveil.co.in; shawnguo@kernel.org; Leo Li
> <leoyang.li@nxp.com>; lorenzo.pieralisi@arm.com;
> catalin.marinas@arm.com; will.deacon@arm.com
> Cc: Mingkai Hu <mingkai.hu@nxp.com>; M.h. Lian
> <minghuan.lian@nxp.com>; Xiaowei Bao <xiaowei.bao@nxp.com>; Z.q. Hou
> <zhiqiang.hou@nxp.com>
> Subject: [PATCHv2 10/25] PCI: mobiveil: fix the INTx process error
> 
> From: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
> 
> In the loop block, there is not code change the loop key, this patch updated
> the loop key by re-read the INTx status register.
> 
> This patch also change to clear the handled INTx status.
> 
> Note: Need MV to test this fix.
> 
> Fixes: 9af6bcb11e12 ("PCI: mobiveil: Add Mobiveil PCIe Host Bridge IP driver")
> Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
> ---
> V2:
>  - Added fixes entry.
> 
>  drivers/pci/controller/pcie-mobiveil.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/pci/controller/pcie-mobiveil.c
> b/drivers/pci/controller/pcie-mobiveil.c
> index 4ba458474e42..78e575e71f4d 100644
> --- a/drivers/pci/controller/pcie-mobiveil.c
> +++ b/drivers/pci/controller/pcie-mobiveil.c
> @@ -361,6 +361,7 @@ static void mobiveil_pcie_isr(struct irq_desc *desc)
>  	/* Handle INTx */
>  	if (intr_status & PAB_INTP_INTX_MASK) {
>  		shifted_status = csr_readl(pcie,
> PAB_INTP_AMBA_MISC_STAT);
> +		shifted_status &= PAB_INTP_INTX_MASK;
>  		shifted_status >>= PAB_INTX_START;
>  		do {
>  			for_each_set_bit(bit, &shifted_status,
> PCI_NUM_INTX) { @@ -372,12 +373,16 @@ static void
> mobiveil_pcie_isr(struct irq_desc *desc)
>  					dev_err_ratelimited(dev,
> "unexpected IRQ, INT%d\n",
>  							    bit);
> 
> -				/* clear interrupt */
> -				csr_writel(pcie,
> -					   shifted_status << PAB_INTX_START,
> +				/* clear interrupt handled */
> +				csr_writel(pcie, 1 << (PAB_INTX_START + bit),
>  					   PAB_INTP_AMBA_MISC_STAT);
>  			}
> -		} while ((shifted_status >> PAB_INTX_START) != 0);
> +
> +			shifted_status = csr_readl(pcie,
> +
> PAB_INTP_AMBA_MISC_STAT);
> +			shifted_status &= PAB_INTP_INTX_MASK;
> +			shifted_status >>= PAB_INTX_START;
> +		} while (shifted_status != 0);
>  	}
> 
>  	/* read extra MSI status register */
> --
> 2.17.1