Re: [PATCH 2/2] PCI: dwc: Add support to configure for ECRC

[Jingoo Han]

On 10/25/20, 3:31 AM, Vidya Sagar wrote:
> 
> DesignWare core has a TLP digest (TD) override bit in one of the control
> registers of ATU. This bit also needs to be programmed for proper ECRC
> functionality. This is currently identified as an issue with DesignWare
> IP version 4.90a. This patch does the required programming in ATU upon
> querying the system policy for ECRC.
>
> Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
> ---
>  drivers/pci/controller/dwc/pcie-designware.c | 8 ++++++--
>  drivers/pci/controller/dwc/pcie-designware.h | 2 ++
>  2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> index b5e438b70cd5..810dcbdbe869 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -245,7 +245,7 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, u8 func_no,
>  				 lower_32_bits(pci_addr));
>  	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_UPPER_TARGET,
>  				 upper_32_bits(pci_addr));
> -	val = type | PCIE_ATU_FUNC_NUM(func_no);
> +	val = type | PCIE_ATU_FUNC_NUM(func_no) | pci->td << PCIE_ATU_TD_SHIFT;
>  	val = upper_32_bits(size - 1) ?
>  		val | PCIE_ATU_INCREASE_REGION_SIZE : val;
>  	dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1, val);
> @@ -295,7 +295,8 @@ static void __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
>  	dw_pcie_writel_dbi(pci, PCIE_ATU_UPPER_TARGET,
>  			   upper_32_bits(pci_addr));
>  	dw_pcie_writel_dbi(pci, PCIE_ATU_CR1, type |
> -			   PCIE_ATU_FUNC_NUM(func_no));
> +			   PCIE_ATU_FUNC_NUM(func_no) |
> +			   pci->td << PCIE_ATU_TD_SHIFT);
>  	dw_pcie_writel_dbi(pci, PCIE_ATU_CR2, PCIE_ATU_ENABLE);
>
>  	/*
> @@ -565,6 +566,9 @@ void dw_pcie_setup(struct dw_pcie *pci)
>  	dev_dbg(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ?
>  		"enabled" : "disabled");
>
> +	if (pci->version == 0x490A)
> +		pci->td = pcie_is_ecrc_enabled();
> +
>  	if (pci->link_gen > 0)
>  		dw_pcie_link_set_max_speed(pci, pci->link_gen);
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> index 21dd06831b50..d34723e42e79 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -90,6 +90,7 @@
>  #define PCIE_ATU_TYPE_IO		0x2
>  #define PCIE_ATU_TYPE_CFG0		0x4
>  #define PCIE_ATU_TYPE_CFG1		0x5
> +#define PCIE_ATU_TD_SHIFT		8
>  #define PCIE_ATU_FUNC_NUM(pf)           ((pf) << 20)
>  #define PCIE_ATU_CR2			0x908
>  #define PCIE_ATU_ENABLE			BIT(31)
> @@ -276,6 +277,7 @@ struct dw_pcie {
>  	int			num_lanes;
>  	int			link_gen;
>  	u8			n_fts[2];
> +	bool			td;	/* TLP Digest (for ECRC purpose) */

If possible, don't add a new variable to 'dw_pcie' structure.
Please find a way to set TD bit without adding a new variable to 'dw_pcie' structure'.

Best regards,
Jingoo Han

>  };
>
>  #define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)
> -- 
> 2.17.1