[U-Boot] [PATCH] TI: DaVinci: Updating EMAC driver for DM365 and DM646x

[s-paulraj at ti.com]

From: Sandeep Paulraj <s-paulraj at ti.com>

The EMAC IP on DM365 and DM646x is slightly different from
that on DM644x. This patch updates the DaVinci EMAC driver
so that EMAC becomes operational on DM365 in U-Boot.
A flag 'CONFIG_DAVINCI_EMAC_VERSION2' is used in the driver.
This flag will need to be defined in the DM365 config file.

Signed-off-by: Sandeep Paulraj <s-paulraj at ti.com>
---
The same modifications work on DM646x in a slightly older version
of U-Boot. So when enabled this should work on the DM6467 EVM as well.
This has at this point of time not been tested on the DM6467 in the latest
version of U-Boot.
 drivers/net/davinci_emac.c |   79 ++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 77 insertions(+), 2 deletions(-)

diff --git a/drivers/net/davinci_emac.c b/drivers/net/davinci_emac.c
index fa8cee4..0d61c91 100644
--- a/drivers/net/davinci_emac.c
+++ b/drivers/net/davinci_emac.c
@@ -107,6 +107,33 @@ static void davinci_eth_mdio_enable(void)
 	while (adap_mdio->CONTROL & MDIO_CONTROL_IDLE) {;}
 }
 
+/* Read a PHY register via MDIO inteface */
+static int mdio_read(int phy_addr, int reg_num)
+{
+	adap_mdio->USERACCESS0 = MDIO_USERACCESS0_GO |
+					MDIO_USERACCESS0_WRITE_READ |
+					((reg_num & 0x1F) << 21) |
+					((phy_addr & 0x1F) << 16);
+
+	/* Wait for command to complete */
+	while ((adap_mdio->USERACCESS0 & MDIO_USERACCESS0_GO) != 0);
+
+	return adap_mdio->USERACCESS0 & 0xFFFF;
+}
+
+/* Write to a PHY register via MDIO inteface */
+void mdio_write(int phy_addr, int reg_num, unsigned int data)
+{
+	/* Wait for User access register to be ready */
+	while ((adap_mdio->USERACCESS0 & MDIO_USERACCESS0_GO) != 0);
+
+	adap_mdio->USERACCESS0 = MDIO_USERACCESS0_GO |
+					MDIO_USERACCESS0_WRITE_WRITE |
+					((reg_num & 0x1F) << 21) |
+					((phy_addr & 0x1F) << 16) |
+					(data & 0xFFFF);
+}
+
 /*
  * Tries to find an active connected PHY. Returns 1 if address if found.
  * If no active PHY (or more than one PHY) found returns 0.
@@ -248,6 +275,31 @@ static int davinci_mii_phy_write(char *devname, unsigned char addr, unsigned cha
 
 #endif
 
+static void emac_gigabit_enable(void)
+{
+	int temp;
+
+	temp = mdio_read(EMAC_MDIO_PHY_NUM, 0);
+
+	if (temp & (1 << 6)) {
+		/*
+		 * Check if link detected is giga-bit
+		 * If Gigabit mode detected, enable gigbit in MAC and PHY
+		 */
+		adap_emac->MACCONTROL |= EMAC_MACCONTROL_GIGFORCE |
+						EMAC_MACCONTROL_GIGABIT_ENABLE;
+
+		/*
+		 * The SYS_CLK which feeds the SOC for giga-bit operation
+		 * does not seem to be enabled after reset as expected.
+		 * Force enabling SYS_CLK by writing to the PHY
+		 */
+		temp = mdio_read(EMAC_MDIO_PHY_NUM, 22);
+		temp |= (1 << 4);
+		mdio_write(EMAC_MDIO_PHY_NUM, 22, temp);
+	}
+}
+
 
 /* Eth device open */
 static int davinci_eth_open(struct eth_device *dev, bd_t *bis)
@@ -261,10 +313,15 @@ static int davinci_eth_open(struct eth_device *dev, bd_t *bis)
 	/* Reset EMAC module and disable interrupts in wrapper */
 	adap_emac->SOFTRESET = 1;
 	while (adap_emac->SOFTRESET != 0) {;}
+#if defined(CONFIG_DAVINCI_EMAC_VERSION2)
+	adap_ewrap->SOFTRST = 1;
+	while (adap_ewrap->SOFTRST != 0);
+#else
 	adap_ewrap->EWCTL = 0;
 	for (cnt = 0; cnt < 5; cnt++) {
 		clkdiv = adap_ewrap->EWCTL;
 	}
+#endif
 
 	rx_desc = emac_rx_desc;
 
@@ -282,6 +339,10 @@ static int davinci_eth_open(struct eth_device *dev, bd_t *bis)
 	adap_emac->MACADDRLO =
 		(davinci_eth_mac_addr[5] << 8) |
 		(davinci_eth_mac_addr[4]);
+#if defined(CONFIG_DAVINCI_EMAC_VERSION2)
+	/* Set the Match and Valid Bits */
+	adap_emac->MACADDRLO |= (1 << 19) | (1 << 20);
+#endif
 
 	adap_emac->MACHASH1 = 0;
 	adap_emac->MACHASH2 = 0;
@@ -347,8 +408,15 @@ static int davinci_eth_open(struct eth_device *dev, bd_t *bis)
 	clkdiv = (EMAC_MDIO_BUS_FREQ / EMAC_MDIO_CLOCK_FREQ) - 1;
 	adap_mdio->CONTROL = ((clkdiv & 0xff) | MDIO_CONTROL_ENABLE | MDIO_CONTROL_FAULT);
 
+#if defined(CONFIG_DAVINCI_EMAC_VERSION2)
+	/* We need to wait for MDIO to start */
+	udelay(1000);
+#endif
+
 	if (!phy.get_link_speed(active_phy_addr))
 		return(0);
+	else
+		emac_gigabit_enable();
 
 	/* Start receive process */
 	adap_emac->RX0HDP = (u_int32_t)emac_rx_desc;
@@ -411,7 +479,11 @@ static void davinci_eth_close(struct eth_device *dev)
 
 	/* Reset EMAC module and disable interrupts in wrapper */
 	adap_emac->SOFTRESET = 1;
+#if defined(CONFIG_DAVINCI_EMAC_VERSION2)
+	adap_ewrap->SOFTRST = 1;
+#else
 	adap_ewrap->EWCTL = 0;
+#endif
 
 	debug_emac("- emac_close\n");
 }
@@ -433,7 +505,8 @@ static int davinci_eth_send_packet (struct eth_device *dev,
 	if (!phy.get_link_speed (active_phy_addr)) {
 		printf ("WARN: emac_send_packet: No link\n");
 		return (ret_status);
-	}
+	} else
+		emac_gigabit_enable();
 
 	/* Check packet size and if < EMAC_MIN_ETHERNET_PKT_SIZE, pad it up */
 	if (length < EMAC_MIN_ETHERNET_PKT_SIZE) {
@@ -456,7 +529,9 @@ static int davinci_eth_send_packet (struct eth_device *dev,
 		if (!phy.get_link_speed (active_phy_addr)) {
 			davinci_eth_ch_teardown (EMAC_CH_TX);
 			return (ret_status);
-		}
+		} else
+			emac_gigabit_enable();
+
 		if (adap_emac->TXINTSTATRAW & 0x01) {
 			ret_status = length;
 			break;
-- 
1.6.0.4