| Grant Likely | 9274498 | 2009-04-25 12:53:39 +0000 | [diff] [blame] | 1 | /* | 
 | 2 |  * MDIO bus driver for the Xilinx TEMAC device | 
 | 3 |  * | 
 | 4 |  * Copyright (c) 2009 Secret Lab Technologies, Ltd. | 
 | 5 |  */ | 
 | 6 |  | 
 | 7 | #include <linux/io.h> | 
 | 8 | #include <linux/netdevice.h> | 
 | 9 | #include <linux/mutex.h> | 
 | 10 | #include <linux/phy.h> | 
 | 11 | #include <linux/of.h> | 
 | 12 | #include <linux/of_device.h> | 
 | 13 | #include <linux/of_mdio.h> | 
 | 14 |  | 
 | 15 | #include "ll_temac.h" | 
 | 16 |  | 
 | 17 | /* --------------------------------------------------------------------- | 
 | 18 |  * MDIO Bus functions | 
 | 19 |  */ | 
 | 20 | static int temac_mdio_read(struct mii_bus *bus, int phy_id, int reg) | 
 | 21 | { | 
 | 22 | 	struct temac_local *lp = bus->priv; | 
 | 23 | 	u32 rc; | 
 | 24 |  | 
 | 25 | 	/* Write the PHY address to the MIIM Access Initiator register. | 
 | 26 | 	 * When the transfer completes, the PHY register value will appear | 
 | 27 | 	 * in the LSW0 register */ | 
 | 28 | 	mutex_lock(&lp->indirect_mutex); | 
 | 29 | 	temac_iow(lp, XTE_LSW0_OFFSET, (phy_id << 5) | reg); | 
 | 30 | 	rc = temac_indirect_in32(lp, XTE_MIIMAI_OFFSET); | 
 | 31 | 	mutex_unlock(&lp->indirect_mutex); | 
 | 32 |  | 
 | 33 | 	dev_dbg(lp->dev, "temac_mdio_read(phy_id=%i, reg=%x) == %x\n", | 
 | 34 | 		phy_id, reg, rc); | 
 | 35 |  | 
 | 36 | 	return rc; | 
 | 37 | } | 
 | 38 |  | 
 | 39 | static int temac_mdio_write(struct mii_bus *bus, int phy_id, int reg, u16 val) | 
 | 40 | { | 
 | 41 | 	struct temac_local *lp = bus->priv; | 
 | 42 |  | 
 | 43 | 	dev_dbg(lp->dev, "temac_mdio_write(phy_id=%i, reg=%x, val=%x)\n", | 
 | 44 | 		phy_id, reg, val); | 
 | 45 |  | 
 | 46 | 	/* First write the desired value into the write data register | 
 | 47 | 	 * and then write the address into the access initiator register | 
 | 48 | 	 */ | 
 | 49 | 	mutex_lock(&lp->indirect_mutex); | 
 | 50 | 	temac_indirect_out32(lp, XTE_MGTDR_OFFSET, val); | 
 | 51 | 	temac_indirect_out32(lp, XTE_MIIMAI_OFFSET, (phy_id << 5) | reg); | 
 | 52 | 	mutex_unlock(&lp->indirect_mutex); | 
 | 53 |  | 
 | 54 | 	return 0; | 
 | 55 | } | 
 | 56 |  | 
 | 57 | int temac_mdio_setup(struct temac_local *lp, struct device_node *np) | 
 | 58 | { | 
 | 59 | 	struct mii_bus *bus; | 
 | 60 | 	const u32 *bus_hz; | 
 | 61 | 	int clk_div; | 
 | 62 | 	int rc, size; | 
 | 63 | 	struct resource res; | 
 | 64 |  | 
 | 65 | 	/* Calculate a reasonable divisor for the clock rate */ | 
 | 66 | 	clk_div = 0x3f; /* worst-case default setting */ | 
 | 67 | 	bus_hz = of_get_property(np, "clock-frequency", &size); | 
 | 68 | 	if (bus_hz && size >= sizeof(*bus_hz)) { | 
 | 69 | 		clk_div = (*bus_hz) / (2500 * 1000 * 2) - 1; | 
 | 70 | 		if (clk_div < 1) | 
 | 71 | 			clk_div = 1; | 
 | 72 | 		if (clk_div > 0x3f) | 
 | 73 | 			clk_div = 0x3f; | 
 | 74 | 	} | 
 | 75 |  | 
 | 76 | 	/* Enable the MDIO bus by asserting the enable bit and writing | 
 | 77 | 	 * in the clock config */ | 
 | 78 | 	mutex_lock(&lp->indirect_mutex); | 
 | 79 | 	temac_indirect_out32(lp, XTE_MC_OFFSET, 1 << 6 | clk_div); | 
 | 80 | 	mutex_unlock(&lp->indirect_mutex); | 
 | 81 |  | 
 | 82 | 	bus = mdiobus_alloc(); | 
 | 83 | 	if (!bus) | 
 | 84 | 		return -ENOMEM; | 
 | 85 |  | 
 | 86 | 	of_address_to_resource(np, 0, &res); | 
 | 87 | 	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx", | 
 | 88 | 		 (unsigned long long)res.start); | 
 | 89 | 	bus->priv = lp; | 
 | 90 | 	bus->name = "Xilinx TEMAC MDIO"; | 
 | 91 | 	bus->read = temac_mdio_read; | 
 | 92 | 	bus->write = temac_mdio_write; | 
 | 93 | 	bus->parent = lp->dev; | 
 | 94 | 	bus->irq = lp->mdio_irqs; /* preallocated IRQ table */ | 
 | 95 |  | 
 | 96 | 	lp->mii_bus = bus; | 
 | 97 |  | 
 | 98 | 	rc = of_mdiobus_register(bus, np); | 
 | 99 | 	if (rc) | 
 | 100 | 		goto err_register; | 
 | 101 |  | 
 | 102 | 	mutex_lock(&lp->indirect_mutex); | 
 | 103 | 	dev_dbg(lp->dev, "MDIO bus registered;  MC:%x\n", | 
 | 104 | 		temac_indirect_in32(lp, XTE_MC_OFFSET)); | 
 | 105 | 	mutex_unlock(&lp->indirect_mutex); | 
 | 106 | 	return 0; | 
 | 107 |  | 
 | 108 |  err_register: | 
 | 109 | 	mdiobus_free(bus); | 
 | 110 | 	return rc; | 
 | 111 | } | 
 | 112 |  | 
 | 113 | void temac_mdio_teardown(struct temac_local *lp) | 
 | 114 | { | 
 | 115 | 	mdiobus_unregister(lp->mii_bus); | 
 | 116 | 	kfree(lp->mii_bus->irq); | 
 | 117 | 	mdiobus_free(lp->mii_bus); | 
 | 118 | 	lp->mii_bus = NULL; | 
 | 119 | } | 
 | 120 |  |