On 27.01.2022 18:37, Robert Hancock wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>
> The GEM controllers on ZynqMP were missing some initialization steps which
> are required in some cases when using SGMII mode, which uses the PS-GTR
> transceivers managed by the phy-zynqmp driver.
>
> The GEM core appears to need a hardware-level reset in order to work
> properly in SGMII mode in cases where the GT reference clock was not
> present at initial power-on. This can be done using a reset mapped to
> the zynqmp-reset driver in the device tree.
>
> Also, when in SGMII mode, the GEM driver needs to ensure the PHY is
> initialized and powered on.
>
> Signed-off-by: Robert Hancock <robert.hancock@xxxxxxxxxx>
Reviewed-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
> ---
> drivers/net/ethernet/cadence/macb.h | 4 ++
> drivers/net/ethernet/cadence/macb_main.c | 63 ++++++++++++++++++++++--
> 2 files changed, 64 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h
> index 9ddbee7de72b..f0a7d8396a4a 100644
> --- a/drivers/net/ethernet/cadence/macb.h
> +++ b/drivers/net/ethernet/cadence/macb.h
> @@ -12,6 +12,7 @@
> #include <linux/ptp_clock_kernel.h>
> #include <linux/net_tstamp.h>
> #include <linux/interrupt.h>
> +#include <linux/phy/phy.h>
>
> #if defined(CONFIG_ARCH_DMA_ADDR_T_64BIT) || defined(CONFIG_MACB_USE_HWSTAMP)
> #define MACB_EXT_DESC
> @@ -1291,6 +1292,9 @@ struct macb {
> u32 wol;
>
> struct macb_ptp_info *ptp_info; /* macb-ptp interface */
> +
> + struct phy *sgmii_phy; /* for ZynqMP SGMII mode */
> +
> #ifdef MACB_EXT_DESC
> uint8_t hw_dma_cap;
> #endif
> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> index a363da928e8b..1ce20bf52f72 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -34,7 +34,9 @@
> #include <linux/udp.h>
> #include <linux/tcp.h>
> #include <linux/iopoll.h>
> +#include <linux/phy/phy.h>
> #include <linux/pm_runtime.h>
> +#include <linux/reset.h>
> #include "macb.h"
>
> /* This structure is only used for MACB on SiFive FU540 devices */
> @@ -2739,10 +2741,14 @@ static int macb_open(struct net_device *dev)
>
> macb_init_hw(bp);
>
> - err = macb_phylink_connect(bp);
> + err = phy_power_on(bp->sgmii_phy);
> if (err)
> goto reset_hw;
>
> + err = macb_phylink_connect(bp);
> + if (err)
> + goto phy_off;
> +
> netif_tx_start_all_queues(dev);
>
> if (bp->ptp_info)
> @@ -2750,6 +2756,9 @@ static int macb_open(struct net_device *dev)
>
> return 0;
>
> +phy_off:
> + phy_power_off(bp->sgmii_phy);
> +
> reset_hw:
> macb_reset_hw(bp);
> for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue)
> @@ -2775,6 +2784,8 @@ static int macb_close(struct net_device *dev)
> phylink_stop(bp->phylink);
> phylink_disconnect_phy(bp->phylink);
>
> + phy_power_off(bp->sgmii_phy);
> +
> spin_lock_irqsave(&bp->lock, flags);
> macb_reset_hw(bp);
> netif_carrier_off(dev);
> @@ -4544,13 +4555,55 @@ static const struct macb_config np4_config = {
> .usrio = &macb_default_usrio,
> };
>
> +static int zynqmp_init(struct platform_device *pdev)
> +{
> + struct net_device *dev = platform_get_drvdata(pdev);
> + struct macb *bp = netdev_priv(dev);
> + int ret;
> +
> + if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII) {
> + /* Ensure PS-GTR PHY device used in SGMII mode is ready */
> + bp->sgmii_phy = devm_phy_get(&pdev->dev, "sgmii-phy");
> +
> + if (IS_ERR(bp->sgmii_phy)) {
> + ret = PTR_ERR(bp->sgmii_phy);
> + dev_err_probe(&pdev->dev, ret,
> + "failed to get PS-GTR PHY\n");
> + return ret;
> + }
> +
> + ret = phy_init(bp->sgmii_phy);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to init PS-GTR PHY: %d\n",
> + ret);
> + return ret;
> + }
> + }
> +
> + /* Fully reset GEM controller at hardware level using zynqmp-reset driver,
> + * if mapped in device tree.
> + */
> + ret = device_reset_optional(&pdev->dev);
> + if (ret) {
> + dev_err_probe(&pdev->dev, ret, "failed to reset controller");
> + phy_exit(bp->sgmii_phy);
> + return ret;
> + }
> +
> + ret = macb_init(pdev);
> + if (ret)
> + phy_exit(bp->sgmii_phy);
> +
> + return ret;
> +}
> +
> static const struct macb_config zynqmp_config = {
> .caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE |
> MACB_CAPS_JUMBO |
> MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_BD_RD_PREFETCH,
> .dma_burst_length = 16,
> .clk_init = macb_clk_init,
> - .init = macb_init,
> + .init = zynqmp_init,
> .jumbo_max_len = 10240,
> .usrio = &macb_default_usrio,
> };
> @@ -4767,7 +4820,7 @@ static int macb_probe(struct platform_device *pdev)
>
> err = macb_mii_init(bp);
> if (err)
> - goto err_out_free_netdev;
> + goto err_out_phy_exit;
>
> netif_carrier_off(dev);
>
> @@ -4792,6 +4845,9 @@ static int macb_probe(struct platform_device *pdev)
> mdiobus_unregister(bp->mii_bus);
> mdiobus_free(bp->mii_bus);
>
> +err_out_phy_exit:
> + phy_exit(bp->sgmii_phy);
> +
> err_out_free_netdev:
> free_netdev(dev);
>
> @@ -4813,6 +4869,7 @@ static int macb_remove(struct platform_device *pdev)
>
> if (dev) {
> bp = netdev_priv(dev);
> + phy_exit(bp->sgmii_phy);
> mdiobus_unregister(bp->mii_bus);
> mdiobus_free(bp->mii_bus);
>
> --
> 2.31.1
>
