On Mon, Oct 14, 2019 at 12:48:29PM +0530, Pankaj Dubey wrote:
> From: Anvesh Salveru <anves...@samsung.com>
> 
> In some platforms, PCIe PHY may have issues which will prevent linkup
> to happen in GEN3 or higher speed. In case equalization fails, link will
> fallback to GEN1.
> 
> DesignWare controller gives flexibility to disable GEN3 equalization
> completely or only phase 2 and 3 of equalization.
> 
> This patch enables the DesignWare driver to disable the PCIe GEN3
> equalization by enabling one of the following quirks:
>  - DWC_EQUALIZATION_DISABLE: To disable GEN3 equalization all phases
>  - DWC_EQ_PHASE_2_3_DISABLE: To disable GEN3 equalization phase 2 & 3
> 
> Platform drivers can set these quirks via "quirk" variable of "dw_pcie"
> struct.
> 
> Signed-off-by: Anvesh Salveru <anves...@samsung.com>
> Signed-off-by: Pankaj Dubey <pankaj.du...@samsung.com>
> Acked-by: Gustavo Pimentel <gustavo.pimen...@synopsys.com>
> Reviewed-by: Andrew Murray <andrew.mur...@arm.com>
> Reviewed-by: Vidya Sagar <vid...@nvidia.com>
> ---
> Changes w.r.t v1:
>  - Rebased on latest linus/master
>  - Added Reviewed-by and Acked-by
> 
>  drivers/pci/controller/dwc/pcie-designware.c | 12 ++++++++++++
>  drivers/pci/controller/dwc/pcie-designware.h |  9 +++++++++
>  2 files changed, 21 insertions(+)

So this is v3 not v2, right ?

Here is v2:

https://patchwork.ozlabs.org/patch/1161958/

> diff --git a/drivers/pci/controller/dwc/pcie-designware.c 
> b/drivers/pci/controller/dwc/pcie-designware.c
> index 820488d..e247d6d 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -556,4 +556,16 @@ void dw_pcie_setup(struct dw_pcie *pci)
>                      PCIE_PL_CHK_REG_CHK_REG_START;
>               dw_pcie_writel_dbi(pci, PCIE_PL_CHK_REG_CONTROL_STATUS, val);
>       }
> +
> +     if (pci->quirk & DWC_EQUALIZATION_DISABLE) {
> +             val = dw_pcie_readl_dbi(pci, PCIE_PORT_GEN3_RELATED);
> +             val |= PORT_LOGIC_GEN3_EQ_DISABLE;
> +             dw_pcie_writel_dbi(pci, PCIE_PORT_GEN3_RELATED, val);
> +     }
> +
> +     if (pci->quirk & DWC_EQ_PHASE_2_3_DISABLE) {
> +             val = dw_pcie_readl_dbi(pci, PCIE_PORT_GEN3_RELATED);
> +             val |= PORT_LOGIC_GEN3_EQ_PHASE_2_3_DISABLE;
> +             dw_pcie_writel_dbi(pci, PCIE_PORT_GEN3_RELATED, val);
> +     }
>  }
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h 
> b/drivers/pci/controller/dwc/pcie-designware.h
> index 5a18e94..7d3fe6f 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -29,6 +29,10 @@
>  #define LINK_WAIT_MAX_IATU_RETRIES   5
>  #define LINK_WAIT_IATU                       9
>  
> +/* Parameters for GEN3 related quirks */
> +#define DWC_EQUALIZATION_DISABLE     BIT(1)
> +#define DWC_EQ_PHASE_2_3_DISABLE     BIT(2)
> +
>  /* Synopsys-specific PCIe configuration registers */
>  #define PCIE_PORT_LINK_CONTROL               0x710
>  #define PORT_LINK_MODE_MASK          GENMASK(21, 16)
> @@ -60,6 +64,10 @@
>  #define PCIE_MSI_INTR0_MASK          0x82C
>  #define PCIE_MSI_INTR0_STATUS                0x830
>  
> +#define PCIE_PORT_GEN3_RELATED               0x890
> +#define PORT_LOGIC_GEN3_EQ_PHASE_2_3_DISABLE BIT(9)
> +#define PORT_LOGIC_GEN3_EQ_DISABLE           BIT(16)
> +
>  #define PCIE_ATU_VIEWPORT            0x900
>  #define PCIE_ATU_REGION_INBOUND              BIT(31)
>  #define PCIE_ATU_REGION_OUTBOUND     0
> @@ -253,6 +261,7 @@ struct dw_pcie {
>       struct dw_pcie_ep       ep;
>       const struct dw_pcie_ops *ops;
>       unsigned int            version;
> +     unsigned int            quirk;
>  };
>  
>  #define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)
> -- 
> 2.7.4
> 

Reply via email to