From 79eacb8b197f7459a75c7d3ec33ceef88475d5a1 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Fri, 4 May 2018 19:23:59 +0300 Subject: [PATCH] memac_init_phy: RGMII fixed-link: pass adjust_link callback to of_phy_connect * The mEMAC configuration for RGMII is held in the IF_MODE register * In the driver, IF_MODE is configured in 2 places (both in fman_memac.c): - fman_memac_init: sets the IF_MODE bit macro IF_MODE_RGMII_AUTO (this translates to setting ENA = 1 - Enable automatic speed selection - RGMII PHY in-band status information is used to select the speed of operation). - fman_memac_adjust_link: brings the RGMII port in ENA = 0 mode (link speed not determined autonomously by the MAC, but set according to SSP). * The issue with the current code is that in the case of RGMII fixed-link, the of_phy_attach function is being called, instead of of_phy_connect with a callback that calls fman_memac_adjust_link. * For this reason, the RGMII port is left in a state with ENA = 1. In most (if not all) RGMII fixed-link setups, the link partner will not send any in-bank link speed information that is expected by the mEMAC. * The effect is that the link speed setting will probably not be correct (and will definitely not be according to the "fixed-link" property in the DTS). * The adjust_link callback seems to be called by the PHY state machine, even for fixed links, exactly once: on "link up". Therefore, this patch ensures that on link up, RGMII fixed links are configured to the link speed that is set in the DTS, and not left with IF_MODE[ENA] = 1. Signed-off-by: Vladimir Oltean --- drivers/net/ethernet/freescale/sdk_dpaa/mac-api.c | 38 ++++++++++++++++++----- 1 file changed, 31 insertions(+), 7 deletions(-) --- a/drivers/net/ethernet/freescale/sdk_dpaa/mac-api.c +++ b/drivers/net/ethernet/freescale/sdk_dpaa/mac-api.c @@ -502,17 +502,41 @@ static int memac_init_phy(struct net_dev struct mac_device *mac_dev) { struct phy_device *phy_dev; + void (*adjust_link_handler)(struct net_device *); if ((macdev2enetinterface(mac_dev) == e_ENET_MODE_XGMII_10000) || - (macdev2enetinterface(mac_dev) == e_ENET_MODE_SGMII_2500) || - of_phy_is_fixed_link(mac_dev->phy_node)) { - phy_dev = of_phy_connect(net_dev, mac_dev->phy_node, - &adjust_link_void, 0, - mac_dev->phy_if); + (macdev2enetinterface(mac_dev) == e_ENET_MODE_SGMII_2500)) { + /* Pass a void link state handler to the PHY state machine + * for XGMII (10G) and SGMII 2.5G, as the hardware does not + * permit dynamic link speed adjustments. */ + adjust_link_handler = adjust_link_void; + } else if (macdev2enetinterface(mac_dev) & e_ENET_IF_RGMII) { + /* Regular RGMII ports connected to a PHY, as well as + * ports that are marked as "fixed-link" in the DTS, + * will have the adjust_link callback. This calls + * fman_memac_adjust_link in order to configure the + * IF_MODE register, which is needed in both cases. + */ + adjust_link_handler = adjust_link; + } else if (of_phy_is_fixed_link(mac_dev->phy_node)) { + /* Pass a void link state handler for fixed-link + * interfaces that are not RGMII. Only RGMII has been + * tested and confirmed to work with fixed-link. Other + * MII interfaces may need further work. + * TODO: Change this as needed. + */ + adjust_link_handler = adjust_link_void; } else { - phy_dev = of_phy_connect(net_dev, mac_dev->phy_node, - &adjust_link, 0, mac_dev->phy_if); + /* MII, RMII, SMII, GMII, SGMII, BASEX ports, + * that are NOT fixed-link. + * TODO: May not be needed for interfaces that + * pass through the SerDes block (*SGMII, XFI). + */ + adjust_link_handler = adjust_link; } + phy_dev = of_phy_connect(net_dev, mac_dev->phy_node, + adjust_link_handler, 0, + mac_dev->phy_if); if (unlikely(phy_dev == NULL) || IS_ERR(phy_dev)) { netdev_err(net_dev, "Could not connect to PHY %s\n",