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

[Russell King - ARM Linux admin]

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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