Device tree aware EMAC driver

Based on BenH's earlier work, this is a new version of the EMAC driver
for the built-in ethernet found on PowerPC 4xx embedded CPUs.  The
same ASIC is also found in the Axon bridge chip.  This new version is
designed to work in the arch/powerpc tree, using the device tree to
probe the device, rather than the old and ugly arch/ppc OCP layer.

This driver is designed to sit alongside the old driver (that lies in
drivers/net/ibm_emac and this one in drivers/net/ibm_newemac).  The
old driver is left in place to support arch/ppc until arch/ppc itself
reaches its final demise (not too long now, with luck).

This driver still has a number of things that could do with cleaning
up, but I think they can be fixed up after merging.  Specifically:
	- Should be adjusted to properly use the dma mapping API.
Axon needs this.
	- Probe logic needs reworking, in conjuction with the general
probing code for of_platform devices.  The dependencies here between
EMAC, MAL, ZMII etc. make this complicated.  At present, it usually
works, because we initialize and register the sub-drivers before the
EMAC driver itself, and (being in driver code) runs after the devices
themselves have been instantiated from the device tree.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 373 insertions, 0 deletions

diff --git a/drivers/net/ibm_newemac/phy.c b/drivers/net/ibm_newemac/phy.c
new file mode 100644
index 00000000000..aa1f0ddf1e3
--- /dev/null
+++ b/drivers/net/ibm_newemac/phy.c
@@ -0,0 +1,373 @@
+/*
+ * drivers/net/ibm_newemac/phy.c
+ *
+ * Driver for PowerPC 4xx on-chip ethernet controller, PHY support.
+ * Borrowed from sungem_phy.c, though I only kept the generic MII
+ * driver for now.
+ *
+ * This file should be shared with other drivers or eventually
+ * merged as the "low level" part of miilib
+ *
+ * (c) 2003, Benjamin Herrenscmidt (benh@kernel.crashing.org)
+ * (c) 2004-2005, Eugene Surovegin <ebs@ebshome.net>
+ *
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/netdevice.h>
+#include <linux/mii.h>
+#include <linux/ethtool.h>
+#include <linux/delay.h>
+
+#include "emac.h"
+#include "phy.h"
+
+static inline int phy_read(struct mii_phy *phy, int reg)
+{
+	return phy->mdio_read(phy->dev, phy->address, reg);
+}
+
+static inline void phy_write(struct mii_phy *phy, int reg, int val)
+{
+	phy->mdio_write(phy->dev, phy->address, reg, val);
+}
+
+int emac_mii_reset_phy(struct mii_phy *phy)
+{
+	int val;
+	int limit = 10000;
+
+	val = phy_read(phy, MII_BMCR);
+	val &= ~(BMCR_ISOLATE | BMCR_ANENABLE);
+	val |= BMCR_RESET;
+	phy_write(phy, MII_BMCR, val);
+
+	udelay(300);
+
+	while (limit--) {
+		val = phy_read(phy, MII_BMCR);
+		if (val >= 0 && (val & BMCR_RESET) == 0)
+			break;
+		udelay(10);
+	}
+	if ((val & BMCR_ISOLATE) && limit > 0)
+		phy_write(phy, MII_BMCR, val & ~BMCR_ISOLATE);
+
+	return limit <= 0;
+}
+
+static int genmii_setup_aneg(struct mii_phy *phy, u32 advertise)
+{
+	int ctl, adv;
+
+	phy->autoneg = AUTONEG_ENABLE;
+	phy->speed = SPEED_10;
+	phy->duplex = DUPLEX_HALF;
+	phy->pause = phy->asym_pause = 0;
+	phy->advertising = advertise;
+
+	ctl = phy_read(phy, MII_BMCR);
+	if (ctl < 0)
+		return ctl;
+	ctl &= ~(BMCR_FULLDPLX | BMCR_SPEED100 | BMCR_SPEED1000 | BMCR_ANENABLE);
+
+	/* First clear the PHY */
+	phy_write(phy, MII_BMCR, ctl);
+
+	/* Setup standard advertise */
+	adv = phy_read(phy, MII_ADVERTISE);
+	if (adv < 0)
+		return adv;
+	adv &= ~(ADVERTISE_ALL | ADVERTISE_100BASE4 | ADVERTISE_PAUSE_CAP |
+		 ADVERTISE_PAUSE_ASYM);
+	if (advertise & ADVERTISED_10baseT_Half)
+		adv |= ADVERTISE_10HALF;
+	if (advertise & ADVERTISED_10baseT_Full)
+		adv |= ADVERTISE_10FULL;
+	if (advertise & ADVERTISED_100baseT_Half)
+		adv |= ADVERTISE_100HALF;
+	if (advertise & ADVERTISED_100baseT_Full)
+		adv |= ADVERTISE_100FULL;
+	if (advertise & ADVERTISED_Pause)
+		adv |= ADVERTISE_PAUSE_CAP;
+	if (advertise & ADVERTISED_Asym_Pause)
+		adv |= ADVERTISE_PAUSE_ASYM;
+	phy_write(phy, MII_ADVERTISE, adv);
+
+	if (phy->features &
+	    (SUPPORTED_1000baseT_Full | SUPPORTED_1000baseT_Half)) {
+		adv = phy_read(phy, MII_CTRL1000);
+		if (adv < 0)
+			return adv;
+		adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
+		if (advertise & ADVERTISED_1000baseT_Full)
+			adv |= ADVERTISE_1000FULL;
+		if (advertise & ADVERTISED_1000baseT_Half)
+			adv |= ADVERTISE_1000HALF;
+		phy_write(phy, MII_CTRL1000, adv);
+	}
+
+	/* Start/Restart aneg */
+	ctl = phy_read(phy, MII_BMCR);
+	ctl |= (BMCR_ANENABLE | BMCR_ANRESTART);
+	phy_write(phy, MII_BMCR, ctl);
+
+	return 0;
+}
+
+static int genmii_setup_forced(struct mii_phy *phy, int speed, int fd)
+{
+	int ctl;
+
+	phy->autoneg = AUTONEG_DISABLE;
+	phy->speed = speed;
+	phy->duplex = fd;
+	phy->pause = phy->asym_pause = 0;
+
+	ctl = phy_read(phy, MII_BMCR);
+	if (ctl < 0)
+		return ctl;
+	ctl &= ~(BMCR_FULLDPLX | BMCR_SPEED100 | BMCR_SPEED1000 | BMCR_ANENABLE);
+
+	/* First clear the PHY */
+	phy_write(phy, MII_BMCR, ctl | BMCR_RESET);
+
+	/* Select speed & duplex */
+	switch (speed) {
+	case SPEED_10:
+		break;
+	case SPEED_100:
+		ctl |= BMCR_SPEED100;
+		break;
+	case SPEED_1000:
+		ctl |= BMCR_SPEED1000;
+		break;
+	default:
+		return -EINVAL;
+	}
+	if (fd == DUPLEX_FULL)
+		ctl |= BMCR_FULLDPLX;
+	phy_write(phy, MII_BMCR, ctl);
+
+	return 0;
+}
+
+static int genmii_poll_link(struct mii_phy *phy)
+{
+	int status;
+
+	/* Clear latched value with dummy read */
+	phy_read(phy, MII_BMSR);
+	status = phy_read(phy, MII_BMSR);
+	if (status < 0 || (status & BMSR_LSTATUS) == 0)
+		return 0;
+	if (phy->autoneg == AUTONEG_ENABLE && !(status & BMSR_ANEGCOMPLETE))
+		return 0;
+	return 1;
+}
+
+static int genmii_read_link(struct mii_phy *phy)
+{
+	if (phy->autoneg == AUTONEG_ENABLE) {
+		int glpa = 0;
+		int lpa = phy_read(phy, MII_LPA) & phy_read(phy, MII_ADVERTISE);
+		if (lpa < 0)
+			return lpa;
+
+		if (phy->features &
+		    (SUPPORTED_1000baseT_Full | SUPPORTED_1000baseT_Half)) {
+			int adv = phy_read(phy, MII_CTRL1000);
+			glpa = phy_read(phy, MII_STAT1000);
+
+			if (glpa < 0 || adv < 0)
+				return adv;
+
+			glpa &= adv << 2;
+		}
+
+		phy->speed = SPEED_10;
+		phy->duplex = DUPLEX_HALF;
+		phy->pause = phy->asym_pause = 0;
+
+		if (glpa & (LPA_1000FULL | LPA_1000HALF)) {
+			phy->speed = SPEED_1000;
+			if (glpa & LPA_1000FULL)
+				phy->duplex = DUPLEX_FULL;
+		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
+			phy->speed = SPEED_100;
+			if (lpa & LPA_100FULL)
+				phy->duplex = DUPLEX_FULL;
+		} else if (lpa & LPA_10FULL)
+			phy->duplex = DUPLEX_FULL;
+
+		if (phy->duplex == DUPLEX_FULL) {
+			phy->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
+			phy->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
+		}
+	} else {
+		int bmcr = phy_read(phy, MII_BMCR);
+		if (bmcr < 0)
+			return bmcr;
+
+		if (bmcr & BMCR_FULLDPLX)
+			phy->duplex = DUPLEX_FULL;
+		else
+			phy->duplex = DUPLEX_HALF;
+		if (bmcr & BMCR_SPEED1000)
+			phy->speed = SPEED_1000;
+		else if (bmcr & BMCR_SPEED100)
+			phy->speed = SPEED_100;
+		else
+			phy->speed = SPEED_10;
+
+		phy->pause = phy->asym_pause = 0;
+	}
+	return 0;
+}
+
+/* Generic implementation for most 10/100/1000 PHYs */
+static struct mii_phy_ops generic_phy_ops = {
+	.setup_aneg	= genmii_setup_aneg,
+	.setup_forced	= genmii_setup_forced,
+	.poll_link	= genmii_poll_link,
+	.read_link	= genmii_read_link
+};
+
+static struct mii_phy_def genmii_phy_def = {
+	.phy_id		= 0x00000000,
+	.phy_id_mask	= 0x00000000,
+	.name		= "Generic MII",
+	.ops		= &generic_phy_ops
+};
+
+/* CIS8201 */
+#define MII_CIS8201_10BTCSR	0x16
+#define  TENBTCSR_ECHO_DISABLE	0x2000
+#define MII_CIS8201_EPCR	0x17
+#define  EPCR_MODE_MASK		0x3000
+#define  EPCR_GMII_MODE		0x0000
+#define  EPCR_RGMII_MODE	0x1000
+#define  EPCR_TBI_MODE		0x2000
+#define  EPCR_RTBI_MODE		0x3000
+#define MII_CIS8201_ACSR	0x1c
+#define  ACSR_PIN_PRIO_SELECT	0x0004
+
+static int cis8201_init(struct mii_phy *phy)
+{
+	int epcr;
+
+	epcr = phy_read(phy, MII_CIS8201_EPCR);
+	if (epcr < 0)
+		return epcr;
+
+	epcr &= ~EPCR_MODE_MASK;
+
+	switch (phy->mode) {
+	case PHY_MODE_TBI:
+		epcr |= EPCR_TBI_MODE;
+		break;
+	case PHY_MODE_RTBI:
+		epcr |= EPCR_RTBI_MODE;
+		break;
+	case PHY_MODE_GMII:
+		epcr |= EPCR_GMII_MODE;
+		break;
+	case PHY_MODE_RGMII:
+	default:
+		epcr |= EPCR_RGMII_MODE;
+	}
+
+	phy_write(phy, MII_CIS8201_EPCR, epcr);
+
+	/* MII regs override strap pins */
+	phy_write(phy, MII_CIS8201_ACSR,
+		  phy_read(phy, MII_CIS8201_ACSR) | ACSR_PIN_PRIO_SELECT);
+
+	/* Disable TX_EN -> CRS echo mode, otherwise 10/HDX doesn't work */
+	phy_write(phy, MII_CIS8201_10BTCSR,
+		  phy_read(phy, MII_CIS8201_10BTCSR) | TENBTCSR_ECHO_DISABLE);
+
+	return 0;
+}
+
+static struct mii_phy_ops cis8201_phy_ops = {
+	.init		= cis8201_init,
+	.setup_aneg	= genmii_setup_aneg,
+	.setup_forced	= genmii_setup_forced,
+	.poll_link	= genmii_poll_link,
+	.read_link	= genmii_read_link
+};
+
+static struct mii_phy_def cis8201_phy_def = {
+	.phy_id		= 0x000fc410,
+	.phy_id_mask	= 0x000ffff0,
+	.name		= "CIS8201 Gigabit Ethernet",
+	.ops		= &cis8201_phy_ops
+};
+
+static struct mii_phy_def *mii_phy_table[] = {
+	&cis8201_phy_def,
+	&genmii_phy_def,
+	NULL
+};
+
+int emac_mii_phy_probe(struct mii_phy *phy, int address)
+{
+	struct mii_phy_def *def;
+	int i;
+	u32 id;
+
+	phy->autoneg = AUTONEG_DISABLE;
+	phy->advertising = 0;
+	phy->address = address;
+	phy->speed = SPEED_10;
+	phy->duplex = DUPLEX_HALF;
+	phy->pause = phy->asym_pause = 0;
+
+	/* Take PHY out of isolate mode and reset it. */
+	if (emac_mii_reset_phy(phy))
+		return -ENODEV;
+
+	/* Read ID and find matching entry */
+	id = (phy_read(phy, MII_PHYSID1) << 16) | phy_read(phy, MII_PHYSID2);
+	for (i = 0; (def = mii_phy_table[i]) != NULL; i++)
+		if ((id & def->phy_id_mask) == def->phy_id)
+			break;
+	/* Should never be NULL (we have a generic entry), but... */
+	if (!def)
+		return -ENODEV;
+
+	phy->def = def;
+
+	/* Determine PHY features if needed */
+	phy->features = def->features;
+	if (!phy->features) {
+		u16 bmsr = phy_read(phy, MII_BMSR);
+		if (bmsr & BMSR_ANEGCAPABLE)
+			phy->features |= SUPPORTED_Autoneg;
+		if (bmsr & BMSR_10HALF)
+			phy->features |= SUPPORTED_10baseT_Half;
+		if (bmsr & BMSR_10FULL)
+			phy->features |= SUPPORTED_10baseT_Full;
+		if (bmsr & BMSR_100HALF)
+			phy->features |= SUPPORTED_100baseT_Half;
+		if (bmsr & BMSR_100FULL)
+			phy->features |= SUPPORTED_100baseT_Full;
+		if (bmsr & BMSR_ESTATEN) {
+			u16 esr = phy_read(phy, MII_ESTATUS);
+			if (esr & ESTATUS_1000_TFULL)
+				phy->features |= SUPPORTED_1000baseT_Full;
+			if (esr & ESTATUS_1000_THALF)
+				phy->features |= SUPPORTED_1000baseT_Half;
+		}
+		phy->features |= SUPPORTED_MII;
+	}
+
+	/* Setup default advertising */
+	phy->advertising = phy->features;
+
+	return 0;
+}
+
+MODULE_LICENSE("GPL");