The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 4b5923249b8fa427943b50b8f35265176472be38 Mon Sep 17 00:00:00 2001

From: Martin Blumenstingl martin.blumenstingl@googlemail.com Date: Thu, 8 Apr 2021 20:38:28 +0200 Subject: [PATCH] net: dsa: lantiq_gswip: Configure all remaining GSWIP_MII_CFG bits

There are a few more bits in the GSWIP_MII_CFG register for which we did rely on the boot-loader (or the hardware defaults) to set them up properly.

For some external RMII PHYs we need to select the GSWIP_MII_CFG_RMII_CLK bit and also we should un-set it for non-RMII PHYs. The GSWIP_MII_CFG_RMII_CLK bit is ignored for other PHY connection modes.

The GSWIP IP also supports in-band auto-negotiation for RGMII PHYs when the GSWIP_MII_CFG_RGMII_IBS bit is set. Clear this bit always as there's no known hardware which uses this (so it is not tested yet).

Clear the xMII isolation bit when set at initialization time if it was previously set by the bootloader. Not doing so could lead to no traffic (neither RX nor TX) on a port with this bit set.

While here, also add the GSWIP_MII_CFG_RESET bit. We don't need to manage it because this bit is self-clearning when set. We still add it here to get a better overview of the GSWIP_MII_CFG register.

Fixes: 14fceff4771e51 ("net: dsa: Add Lantiq / Intel DSA driver for vrx200") Cc: stable@vger.kernel.org Suggested-by: Hauke Mehrtens hauke@hauke-m.de Acked-by: Hauke Mehrtens hauke@hauke-m.de Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com Reviewed-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: David S. Miller davem@davemloft.net

diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c index 126d4ea868ba..bf5c62e5c0b0 100644 --- a/drivers/net/dsa/lantiq_gswip.c +++ b/drivers/net/dsa/lantiq_gswip.c @@ -93,8 +93,12 @@

/* GSWIP MII Registers */ #define GSWIP_MII_CFGp(p) (0x2 * (p)) +#define GSWIP_MII_CFG_RESET BIT(15) #define GSWIP_MII_CFG_EN BIT(14) +#define GSWIP_MII_CFG_ISOLATE BIT(13) #define GSWIP_MII_CFG_LDCLKDIS BIT(12) +#define GSWIP_MII_CFG_RGMII_IBS BIT(8) +#define GSWIP_MII_CFG_RMII_CLK BIT(7) #define GSWIP_MII_CFG_MODE_MIIP 0x0 #define GSWIP_MII_CFG_MODE_MIIM 0x1 #define GSWIP_MII_CFG_MODE_RMIIP 0x2 @@ -821,9 +825,11 @@ static int gswip_setup(struct dsa_switch *ds) /* Configure the MDIO Clock 2.5 MHz */ gswip_mdio_mask(priv, 0xff, 0x09, GSWIP_MDIO_MDC_CFG1);

- /* Disable the xMII link */ + /* Disable the xMII interface and clear it's isolation bit */ for (i = 0; i < priv->hw_info->max_ports; i++) - gswip_mii_mask_cfg(priv, GSWIP_MII_CFG_EN, 0, i); + gswip_mii_mask_cfg(priv, + GSWIP_MII_CFG_EN | GSWIP_MII_CFG_ISOLATE, + 0, i);

/* enable special tag insertion on cpu port */ gswip_switch_mask(priv, 0, GSWIP_FDMA_PCTRL_STEN, @@ -1597,6 +1603,9 @@ static void gswip_phylink_mac_config(struct dsa_switch *ds, int port, break; case PHY_INTERFACE_MODE_RMII: miicfg |= GSWIP_MII_CFG_MODE_RMIIM; + + /* Configure the RMII clock as output: */ + miicfg |= GSWIP_MII_CFG_RMII_CLK; break; case PHY_INTERFACE_MODE_RGMII: case PHY_INTERFACE_MODE_RGMII_ID: @@ -1609,7 +1618,11 @@ static void gswip_phylink_mac_config(struct dsa_switch *ds, int port, "Unsupported interface: %d\n", state->interface); return; } - gswip_mii_mask_cfg(priv, GSWIP_MII_CFG_MODE_MASK, miicfg, port); + + gswip_mii_mask_cfg(priv, + GSWIP_MII_CFG_MODE_MASK | GSWIP_MII_CFG_RMII_CLK | + GSWIP_MII_CFG_RGMII_IBS | GSWIP_MII_CFG_LDCLKDIS, + miicfg, port);

switch (state->interface) { case PHY_INTERFACE_MODE_RGMII_ID: