From dd8f467eda72cdaff50e4636c382709124956da3 Mon Sep 17 00:00:00 2001 From: Tobias Waldekranz Date: Wed, 26 Jan 2022 17:05:42 +0100 Subject: [PATCH] net/fsl: xgmac_mdio: Support setting the MDC frequency Support the standard "clock-frequency" attribute to set the generated MDC frequency. If not specified, the driver will leave the divisor bits untouched. Signed-off-by: Tobias Waldekranz Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/xgmac_mdio.c | 38 ++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/freescale/xgmac_mdio.c b/drivers/net/ethernet/freescale/xgmac_mdio.c index 18bf2370d45a..d38d0c372585 100644 --- a/drivers/net/ethernet/freescale/xgmac_mdio.c +++ b/drivers/net/ethernet/freescale/xgmac_mdio.c @@ -14,6 +14,7 @@ #include #include +#include #include #include #include @@ -36,7 +37,7 @@ struct tgec_mdio_controller { } __packed; #define MDIO_STAT_ENC BIT(6) -#define MDIO_STAT_CLKDIV(x) (((x>>1) & 0xff) << 8) +#define MDIO_STAT_CLKDIV(x) (((x) & 0x1ff) << 7) #define MDIO_STAT_BSY BIT(0) #define MDIO_STAT_RD_ER BIT(1) #define MDIO_STAT_PRE_DIS BIT(5) @@ -51,6 +52,8 @@ struct tgec_mdio_controller { struct mdio_fsl_priv { struct tgec_mdio_controller __iomem *mdio_base; + struct clk *enet_clk; + u32 mdc_freq; bool is_little_endian; bool has_a009885; bool has_a011043; @@ -255,6 +258,35 @@ irq_restore: return ret; } +static int xgmac_mdio_set_mdc_freq(struct mii_bus *bus) +{ + struct mdio_fsl_priv *priv = (struct mdio_fsl_priv *)bus->priv; + struct tgec_mdio_controller __iomem *regs = priv->mdio_base; + struct device *dev = bus->parent; + u32 mdio_stat, div; + + if (device_property_read_u32(dev, "clock-frequency", &priv->mdc_freq)) + return 0; + + priv->enet_clk = devm_clk_get(dev, NULL); + if (IS_ERR(priv->enet_clk)) { + dev_err(dev, "Input clock unknown, not changing MDC frequency"); + return PTR_ERR(priv->enet_clk); + } + + div = ((clk_get_rate(priv->enet_clk) / priv->mdc_freq) - 1) / 2; + if (div < 5 || div > 0x1ff) { + dev_err(dev, "Requested MDC frequecy is out of range, ignoring"); + return -EINVAL; + } + + mdio_stat = xgmac_read32(®s->mdio_stat, priv->is_little_endian); + mdio_stat &= ~MDIO_STAT_CLKDIV(0x1ff); + mdio_stat |= MDIO_STAT_CLKDIV(div); + xgmac_write32(mdio_stat, ®s->mdio_stat, priv->is_little_endian); + return 0; +} + static void xgmac_mdio_set_suppress_preamble(struct mii_bus *bus) { struct mdio_fsl_priv *priv = (struct mdio_fsl_priv *)bus->priv; @@ -319,6 +351,10 @@ static int xgmac_mdio_probe(struct platform_device *pdev) xgmac_mdio_set_suppress_preamble(bus); + ret = xgmac_mdio_set_mdc_freq(bus); + if (ret) + return ret; + fwnode = pdev->dev.fwnode; if (is_of_node(fwnode)) ret = of_mdiobus_register(bus, to_of_node(fwnode));