Commit dd8f467e authored by Tobias Waldekranz's avatar Tobias Waldekranz Committed by David S. Miller
Browse files

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: default avatarTobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 909bea73

drivers/net/ethernet/freescale/xgmac_mdio.c

+37 −1
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 


#include <linux/acpi.h>

#include <linux/acpi_mdio.h>

#include <linux/clk.h>

#include <linux/interrupt.h>

#include <linux/kernel.h>

#include <linux/mdio.h>
@@ -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 @@ static int xgmac_mdio_read(struct mii_bus *bus, int phy_id, int regnum) 
	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(&regs->mdio_stat, priv->is_little_endian);

	mdio_stat &= ~MDIO_STAT_CLKDIV(0x1ff);

	mdio_stat |= MDIO_STAT_CLKDIV(div);

	xgmac_write32(mdio_stat, &regs->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));