Re: [PATCH v2 5/5] net: ti: icssg-prueth: am65x SR2.0 add 10M full duplex support

[Roger Quadros <rogerq@kernel.org>]

On 07/08/2023 14:00, MD Danish Anwar wrote:
> From: Grygorii Strashko <grygorii.strashko@ti.com>
> 
> For AM65x SR2.0 it's required to enable IEP1 in raw 64bit mode which is
> used by PRU FW to monitor the link and apply w/a for 10M link issue.
> Note. No public errata available yet.
> 
> Without this w/a the PRU FW will stuck if link state changes under TX
> traffic pressure.
> 
> Hence, add support for 10M full duplex for AM65x SR2.0:
>  - add new IEP API to enable IEP, but without PTP support
>  - add pdata quirk_10m_link_issue to enable 10M link issue w/a.
> 
> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
> Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
> ---
>  drivers/net/ethernet/ti/icssg/icss_iep.c     | 26 ++++++++++++++++++++
>  drivers/net/ethernet/ti/icssg/icss_iep.h     |  2 ++
>  drivers/net/ethernet/ti/icssg/icssg_config.c |  6 +++++
>  drivers/net/ethernet/ti/icssg/icssg_prueth.c | 17 +++++++++++--
>  4 files changed, 49 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/ti/icssg/icss_iep.c b/drivers/net/ethernet/ti/icssg/icss_iep.c
> index 455c803dea36..527f17430f05 100644
> --- a/drivers/net/ethernet/ti/icssg/icss_iep.c
> +++ b/drivers/net/ethernet/ti/icssg/icss_iep.c
> @@ -721,6 +721,32 @@ void icss_iep_put(struct icss_iep *iep)
>  }
>  EXPORT_SYMBOL_GPL(icss_iep_put);
>  
> +void icss_iep_init_fw(struct icss_iep *iep)
> +{
> +	/* start IEP for FW use in raw 64bit mode, no PTP support */
> +	iep->clk_tick_time = iep->def_inc;
> +	iep->cycle_time_ns = 0;
> +	iep->ops = NULL;
> +	iep->clockops_data = NULL;
> +	icss_iep_set_default_inc(iep, iep->def_inc);
> +	icss_iep_set_compensation_inc(iep, iep->def_inc);
> +	icss_iep_set_compensation_count(iep, 0);
> +	regmap_write(iep->map, ICSS_IEP_SYNC_PWIDTH_REG, iep->refclk_freq / 10); /* 100 ms pulse */
> +	regmap_write(iep->map, ICSS_IEP_SYNC0_PERIOD_REG, 0);
> +	if (iep->plat_data->flags & ICSS_IEP_SLOW_COMPEN_REG_SUPPORT)
> +		icss_iep_set_slow_compensation_count(iep, 0);
> +
> +	icss_iep_enable(iep);
> +	icss_iep_settime(iep, 0);
> +}
> +EXPORT_SYMBOL_GPL(icss_iep_init_fw);
> +
> +void icss_iep_exit_fw(struct icss_iep *iep)
> +{
> +	icss_iep_disable(iep);
> +}
> +EXPORT_SYMBOL_GPL(icss_iep_exit_fw);
> +
>  int icss_iep_init(struct icss_iep *iep, const struct icss_iep_clockops *clkops,
>  		  void *clockops_data, u32 cycle_time_ns)
>  {
> diff --git a/drivers/net/ethernet/ti/icssg/icss_iep.h b/drivers/net/ethernet/ti/icssg/icss_iep.h
> index 9c7f4d0a0916..803a4b714893 100644
> --- a/drivers/net/ethernet/ti/icssg/icss_iep.h
> +++ b/drivers/net/ethernet/ti/icssg/icss_iep.h
> @@ -35,5 +35,7 @@ int icss_iep_exit(struct icss_iep *iep);
>  int icss_iep_get_count_low(struct icss_iep *iep);
>  int icss_iep_get_count_hi(struct icss_iep *iep);
>  int icss_iep_get_ptp_clock_idx(struct icss_iep *iep);
> +void icss_iep_init_fw(struct icss_iep *iep);
> +void icss_iep_exit_fw(struct icss_iep *iep);
>  
>  #endif /* __NET_TI_ICSS_IEP_H */
> diff --git a/drivers/net/ethernet/ti/icssg/icssg_config.c b/drivers/net/ethernet/ti/icssg/icssg_config.c
> index ab648d3efe85..4c2b5d496670 100644
> --- a/drivers/net/ethernet/ti/icssg/icssg_config.c
> +++ b/drivers/net/ethernet/ti/icssg/icssg_config.c
> @@ -210,6 +210,9 @@ void icssg_config_ipg(struct prueth_emac *emac)
>  	case SPEED_100:
>  		icssg_mii_update_ipg(prueth->mii_rt, slice, MII_RT_TX_IPG_100M);
>  		break;
> +	case SPEED_10:
> +		icssg_mii_update_ipg(prueth->mii_rt, slice, MII_RT_TX_IPG_100M);
> +		break;
>  	default:
>  		/* Other links speeds not supported */
>  		netdev_err(emac->ndev, "Unsupported link speed\n");
> @@ -440,6 +443,9 @@ void icssg_config_set_speed(struct prueth_emac *emac)
>  	case SPEED_100:
>  		fw_speed = FW_LINK_SPEED_100M;
>  		break;
> +	case SPEED_10:
> +		fw_speed = FW_LINK_SPEED_10M;
> +		break;
>  	default:
>  		/* Other links speeds not supported */
>  		netdev_err(emac->ndev, "Unsupported link speed\n");
> diff --git a/drivers/net/ethernet/ti/icssg/icssg_prueth.c b/drivers/net/ethernet/ti/icssg/icssg_prueth.c
> index b82a718fd602..216918162960 100644
> --- a/drivers/net/ethernet/ti/icssg/icssg_prueth.c
> +++ b/drivers/net/ethernet/ti/icssg/icssg_prueth.c
> @@ -1131,7 +1131,6 @@ static int emac_phy_connect(struct prueth_emac *emac)
>  
>  	/* remove unsupported modes */
>  	phy_remove_link_mode(ndev->phydev, ETHTOOL_LINK_MODE_10baseT_Half_BIT);
> -	phy_remove_link_mode(ndev->phydev, ETHTOOL_LINK_MODE_10baseT_Full_BIT);
>  	phy_remove_link_mode(ndev->phydev, ETHTOOL_LINK_MODE_100baseT_Half_BIT);
>  	phy_remove_link_mode(ndev->phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
>  	phy_remove_link_mode(ndev->phydev, ETHTOOL_LINK_MODE_Pause_BIT);
> @@ -2081,13 +2080,20 @@ static int prueth_probe(struct platform_device *pdev)
>  		goto free_pool;
>  	}
>  
> +	if (prueth->pdata.quirk_10m_link_issue) {
> +		/* Enable IEP1 for FW in 64bit mode as W/A for 10M FD link detect issue under TX
> +		 * traffic.
> +		 */
> +		icss_iep_init_fw(prueth->iep1);

This is the only place where IEP1 is used.
You should add all IEP1 related code in this patch.

> +	}
> +
>  	/* setup netdev interfaces */
>  	if (eth0_node) {
>  		ret = prueth_netdev_init(prueth, eth0_node);
>  		if (ret) {
>  			dev_err_probe(dev, ret, "netdev init %s failed\n",
>  				      eth0_node->name);
> -			goto netdev_exit;
> +			goto exit_iep;
>  		}
>  		prueth->emac[PRUETH_MAC0]->iep = prueth->iep0;
>  	}
> @@ -2158,6 +2164,10 @@ static int prueth_probe(struct platform_device *pdev)
>  		prueth_netdev_exit(prueth, eth_node);
>  	}
>  
> +exit_iep:
> +	if (prueth->pdata.quirk_10m_link_issue)
> +		icss_iep_exit_fw(prueth->iep1);
> +
>  free_pool:
>  	gen_pool_free(prueth->sram_pool,
>  		      (unsigned long)prueth->msmcram.va, msmc_ram_size);
> @@ -2203,6 +2213,9 @@ static void prueth_remove(struct platform_device *pdev)
>  		prueth_netdev_exit(prueth, eth_node);
>  	}
>  
> +	if (prueth->pdata.quirk_10m_link_issue)
> +		icss_iep_exit_fw(prueth->iep1);
> +
>  	icss_iep_put(prueth->iep1);
>  	icss_iep_put(prueth->iep0);
>  

-- 
cheers,
-roger