Re: [PATCH 4/6] PCI: mobiveil: Add workaround for unsupported request error

From: Russell King - ARM Linux admin
Date: Tue Sep 24 2019 - 12:56:18 EST


On Mon, Sep 16, 2019 at 10:17:40AM +0800, Xiaowei Bao wrote:
> Errata: unsupported request error on inbound posted write
> transaction, PCIe controller reports advisory error instead
> of uncorrectable error message to RC.
>
> Signed-off-by: Xiaowei Bao <xiaowei.bao@xxxxxxx>
> ---
> drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c | 13 +++++++++++++
> drivers/pci/controller/mobiveil/pcie-mobiveil.h | 4 ++++
> 2 files changed, 17 insertions(+)
>
> diff --git a/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c b/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
> index 7bfec51..5bc9ed7 100644
> --- a/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
> +++ b/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
> @@ -49,6 +49,19 @@ static void ls_pcie_g4_ep_init(struct mobiveil_pcie_ep *ep)
> struct mobiveil_pcie *mv_pci = to_mobiveil_pcie_from_ep(ep);
> int win_idx;
> u8 bar;
> + u32 val;
> +
> + /*
> + * Errata: unsupported request error on inbound posted write
> + * transaction, PCIe controller reports advisory error instead
> + * of uncorrectable error message to RC.
> + * workaround: set the bit20(unsupported_request_Error_severity) with
> + * value 1 in uncorrectable_Error_Severity_Register, make the
> + * unsupported request error generate the fatal error.
> + */
> + val = csr_readl(mv_pci, CFG_UNCORRECTABLE_ERROR_SEVERITY);
> + val |= 1 << UNSUPPORTED_REQUEST_ERROR_SHIFT;

BIT(UNSUPPORTED_REQUEST_ERROR_SHIFT) ?

> + csr_writel(mv_pci, val, CFG_UNCORRECTABLE_ERROR_SEVERITY);
>
> ep->bar_num = PCIE_LX2_BAR_NUM;
>
> diff --git a/drivers/pci/controller/mobiveil/pcie-mobiveil.h b/drivers/pci/controller/mobiveil/pcie-mobiveil.h
> index 7308fa4..a40707e 100644
> --- a/drivers/pci/controller/mobiveil/pcie-mobiveil.h
> +++ b/drivers/pci/controller/mobiveil/pcie-mobiveil.h
> @@ -123,6 +123,10 @@
> #define GPEX_BAR_SIZE_UDW 0x4DC
> #define GPEX_BAR_SELECT 0x4E0
>
> +#define CFG_UNCORRECTABLE_ERROR_SEVERITY 0x10c
> +#define UNSUPPORTED_REQUEST_ERROR_SHIFT 20
> +#define CFG_UNCORRECTABLE_ERROR_MASK 0x108
> +
> /* starting offset of INTX bits in status register */
> #define PAB_INTX_START 5
>
> --
> 2.9.5
>
>
> _______________________________________________
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>

--
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