[Skiboot] [PATCH] hw/npu2-hw-procedures: Enable RX auto recal on OpenCAPI links

[Frederic Barrat]

Le 12/09/2018 à 05:45, Andrew Donnellan a écrit :
> The RX_RC_ENABLE_AUTO_RECAL flag is required on OpenCAPI but not NVLink.
> 
> Traditionally, Hostboot sets this value according to the machine type.
> However, now that Witherspoon supports both NVLink and OpenCAPI, it can't
> tell whether or not a link is OpenCAPI.
> 
> So instead, set it in skiboot, where it will only be triggered after we've
> done device detection and found an OpenCAPI device.
> 
> Signed-off-by: Andrew Donnellan <andrew.donnellan at au1.ibm.com>
> ---

Reviewed-by: Frederic Barrat <fbarrat at linux.ibm.com>


>   hw/npu2-hw-procedures.c | 8 ++++++++
>   1 file changed, 8 insertions(+)
> 
> diff --git a/hw/npu2-hw-procedures.c b/hw/npu2-hw-procedures.c
> index 86864629a66b..c30e1b03e8aa 100644
> --- a/hw/npu2-hw-procedures.c
> +++ b/hw/npu2-hw-procedures.c
> @@ -96,6 +96,7 @@ struct npu2_phy_reg NPU2_PHY_TX_NSEG_MAIN_EN		= {0x359, 51, 7};
>   struct npu2_phy_reg NPU2_PHY_RX_HIST_MIN_EYE_WIDTH	= {0x24e, 54, 8};
>   struct npu2_phy_reg NPU2_PHY_RX_HIST_MIN_EYE_WIDTH_LANE	= {0x24e, 49, 5};
>   struct npu2_phy_reg NPU2_PHY_RX_HIST_MIN_EYE_WIDTH_VALID= {0x24e, 48, 1};
> +struct npu2_phy_reg NPU2_PHY_RX_RC_ENABLE_AUTO_RECAL    = {0x25c, 51, 1};
> 
>   struct npu2_phy_reg NPU2_PHY_RX_CLKDIST_PDWN		= {0x204, 48, 3};
>   struct npu2_phy_reg NPU2_PHY_RX_IREF_PDWN		= {0x230, 54, 1};
> @@ -1009,6 +1010,13 @@ void npu2_opencapi_bump_ui_lane(struct npu2_dev *dev)
> 
>   void npu2_opencapi_phy_setup(struct npu2_dev *dev)
>   {
> +	/*
> +	 * This is only required for OpenCAPI - Hostboot tries to set this
> +	 * on systems where it can tell a link is OpenCAPI, but for
> +	 * Witherspoon it needs to be done in skiboot after device detection.
> +	 */
> +	phy_write(dev, &NPU2_PHY_RX_RC_ENABLE_AUTO_RECAL, 0x1);
> +
>   	run_procedure(dev, 4); /* procedure_phy_reset */
>   	run_procedure(dev, 5); /* procedure_phy_tx_zcal */
>   	run_procedure(dev, 6); /* procedure_phy_rx_dccal */
>