Add EP93xx ethernet driver

Added ethernet driver for EP93xx SoCs

Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
diff --git a/drivers/net/ep93xx_eth.c b/drivers/net/ep93xx_eth.c
new file mode 100644
index 0000000..4e39948
--- /dev/null
+++ b/drivers/net/ep93xx_eth.c
@@ -0,0 +1,653 @@
+/*
+ * Cirrus Logic EP93xx ethernet MAC / MII driver.
+ *
+ * Copyright (C) 2010, 2009
+ * Matthias Kaehlcke <matthias@kaehlcke.net>
+ *
+ * Copyright (C) 2004, 2005
+ * Cory T. Tusar, Videon Central, Inc., <ctusar@videon-central.com>
+ *
+ * Based on the original eth.[ch] Cirrus Logic EP93xx Rev D. Ethernet Driver,
+ * which is
+ *
+ * (C) Copyright 2002 2003
+ * Adam Bezanson, Network Audio Technologies, Inc.
+ * <bezanson@netaudiotech.com>
+ *
+ * See file CREDITS for list of people who contributed to this project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <command.h>
+#include <common.h>
+#include <asm/arch/ep93xx.h>
+#include <asm/io.h>
+#include <malloc.h>
+#include <miiphy.h>
+#include <linux/types.h>
+#include "ep93xx_eth.h"
+
+#define GET_PRIV(eth_dev)	((struct ep93xx_priv *)(eth_dev)->priv)
+#define GET_REGS(eth_dev)	(GET_PRIV(eth_dev)->regs)
+
+/* ep93xx_miiphy ops forward declarations */
+static int ep93xx_miiphy_read(char * const dev, unsigned char const addr,
+			unsigned char const reg, unsigned short * const value);
+static int ep93xx_miiphy_write(char * const dev, unsigned char const addr,
+			unsigned char const reg, unsigned short const value);
+
+#if defined(EP93XX_MAC_DEBUG)
+/**
+ * Dump ep93xx_mac values to the terminal.
+ */
+static void dump_dev(struct eth_device *dev)
+{
+	struct ep93xx_priv *priv = GET_PRIV(dev);
+	int i;
+
+	printf("\ndump_dev()\n");
+	printf("  rx_dq.base	     %p\n", priv->rx_dq.base);
+	printf("  rx_dq.current	     %p\n", priv->rx_dq.current);
+	printf("  rx_dq.end	     %p\n", priv->rx_dq.end);
+	printf("  rx_sq.base	     %p\n", priv->rx_sq.base);
+	printf("  rx_sq.current	     %p\n", priv->rx_sq.current);
+	printf("  rx_sq.end	     %p\n", priv->rx_sq.end);
+
+	for (i = 0; i < NUMRXDESC; i++)
+		printf("  rx_buffer[%2.d]      %p\n", i, NetRxPackets[i]);
+
+	printf("  tx_dq.base	     %p\n", priv->tx_dq.base);
+	printf("  tx_dq.current	     %p\n", priv->tx_dq.current);
+	printf("  tx_dq.end	     %p\n", priv->tx_dq.end);
+	printf("  tx_sq.base	     %p\n", priv->tx_sq.base);
+	printf("  tx_sq.current	     %p\n", priv->tx_sq.current);
+	printf("  tx_sq.end	     %p\n", priv->tx_sq.end);
+}
+
+/**
+ * Dump all RX status queue entries to the terminal.
+ */
+static void dump_rx_status_queue(struct eth_device *dev)
+{
+	struct ep93xx_priv *priv = GET_PRIV(dev);
+	int i;
+
+	printf("\ndump_rx_status_queue()\n");
+	printf("  descriptor address	 word1		 word2\n");
+	for (i = 0; i < NUMRXDESC; i++) {
+		printf("  [ %p ]	     %08X	 %08X\n",
+			priv->rx_sq.base + i,
+			(priv->rx_sq.base + i)->word1,
+			(priv->rx_sq.base + i)->word2);
+	}
+}
+
+/**
+ * Dump all RX descriptor queue entries to the terminal.
+ */
+static void dump_rx_descriptor_queue(struct eth_device *dev)
+{
+	struct ep93xx_priv *priv = GET_PRIV(dev);
+	int i;
+
+	printf("\ndump_rx_descriptor_queue()\n");
+	printf("  descriptor address	 word1		 word2\n");
+	for (i = 0; i < NUMRXDESC; i++) {
+		printf("  [ %p ]	     %08X	 %08X\n",
+			priv->rx_dq.base + i,
+			(priv->rx_dq.base + i)->word1,
+			(priv->rx_dq.base + i)->word2);
+	}
+}
+
+/**
+ * Dump all TX descriptor queue entries to the terminal.
+ */
+static void dump_tx_descriptor_queue(struct eth_device *dev)
+{
+	struct ep93xx_priv *priv = GET_PRIV(dev);
+	int i;
+
+	printf("\ndump_tx_descriptor_queue()\n");
+	printf("  descriptor address	 word1		 word2\n");
+	for (i = 0; i < NUMTXDESC; i++) {
+		printf("  [ %p ]	     %08X	 %08X\n",
+			priv->tx_dq.base + i,
+			(priv->tx_dq.base + i)->word1,
+			(priv->tx_dq.base + i)->word2);
+	}
+}
+
+/**
+ * Dump all TX status queue entries to the terminal.
+ */
+static void dump_tx_status_queue(struct eth_device *dev)
+{
+	struct ep93xx_priv *priv = GET_PRIV(dev);
+	int i;
+
+	printf("\ndump_tx_status_queue()\n");
+	printf("  descriptor address	 word1\n");
+	for (i = 0; i < NUMTXDESC; i++) {
+		printf("  [ %p ]	     %08X\n",
+			priv->rx_sq.base + i,
+			(priv->rx_sq.base + i)->word1);
+	}
+}
+#else
+#define dump_dev(x)
+#define dump_rx_descriptor_queue(x)
+#define dump_rx_status_queue(x)
+#define dump_tx_descriptor_queue(x)
+#define dump_tx_status_queue(x)
+#endif	/* defined(EP93XX_MAC_DEBUG) */
+
+/**
+ * Reset the EP93xx MAC by twiddling the soft reset bit and spinning until
+ * it's cleared.
+ */
+static void ep93xx_mac_reset(struct eth_device *dev)
+{
+	struct mac_regs *mac = GET_REGS(dev);
+	uint32_t value;
+
+	debug("+ep93xx_mac_reset");
+
+	value = readl(&mac->selfctl);
+	value |= SELFCTL_RESET;
+	writel(value, &mac->selfctl);
+
+	while (readl(&mac->selfctl) & SELFCTL_RESET)
+		; /* noop */
+
+	debug("-ep93xx_mac_reset");
+}
+
+/* Eth device open */
+static int ep93xx_eth_open(struct eth_device *dev, bd_t *bd)
+{
+	struct ep93xx_priv *priv = GET_PRIV(dev);
+	struct mac_regs *mac = GET_REGS(dev);
+	uchar *mac_addr = dev->enetaddr;
+	int i;
+
+	debug("+ep93xx_eth_open");
+
+	/* Reset the MAC */
+	ep93xx_mac_reset(dev);
+
+	/* Reset the descriptor queues' current and end address values */
+	priv->tx_dq.current = priv->tx_dq.base;
+	priv->tx_dq.end = (priv->tx_dq.base + NUMTXDESC);
+
+	priv->tx_sq.current = priv->tx_sq.base;
+	priv->tx_sq.end = (priv->tx_sq.base + NUMTXDESC);
+
+	priv->rx_dq.current = priv->rx_dq.base;
+	priv->rx_dq.end = (priv->rx_dq.base + NUMRXDESC);
+
+	priv->rx_sq.current = priv->rx_sq.base;
+	priv->rx_sq.end = (priv->rx_sq.base + NUMRXDESC);
+
+	/*
+	 * Set the transmit descriptor and status queues' base address,
+	 * current address, and length registers.  Set the maximum frame
+	 * length and threshold. Enable the transmit descriptor processor.
+	 */
+	writel((uint32_t)priv->tx_dq.base, &mac->txdq.badd);
+	writel((uint32_t)priv->tx_dq.base, &mac->txdq.curadd);
+	writel(sizeof(struct tx_descriptor) * NUMTXDESC, &mac->txdq.blen);
+
+	writel((uint32_t)priv->tx_sq.base, &mac->txstsq.badd);
+	writel((uint32_t)priv->tx_sq.base, &mac->txstsq.curadd);
+	writel(sizeof(struct tx_status) * NUMTXDESC, &mac->txstsq.blen);
+
+	writel(0x00040000, &mac->txdthrshld);
+	writel(0x00040000, &mac->txststhrshld);
+
+	writel((TXSTARTMAX << 0) | (PKTSIZE_ALIGN << 16), &mac->maxfrmlen);
+	writel(BMCTL_TXEN, &mac->bmctl);
+
+	/*
+	 * Set the receive descriptor and status queues' base address,
+	 * current address, and length registers.  Enable the receive
+	 * descriptor processor.
+	 */
+	writel((uint32_t)priv->rx_dq.base, &mac->rxdq.badd);
+	writel((uint32_t)priv->rx_dq.base, &mac->rxdq.curadd);
+	writel(sizeof(struct rx_descriptor) * NUMRXDESC, &mac->rxdq.blen);
+
+	writel((uint32_t)priv->rx_sq.base, &mac->rxstsq.badd);
+	writel((uint32_t)priv->rx_sq.base, &mac->rxstsq.curadd);
+	writel(sizeof(struct rx_status) * NUMRXDESC, &mac->rxstsq.blen);
+
+	writel(0x00040000, &mac->rxdthrshld);
+
+	writel(BMCTL_RXEN, &mac->bmctl);
+
+	writel(0x00040000, &mac->rxststhrshld);
+
+	/* Wait until the receive descriptor processor is active */
+	while (!(readl(&mac->bmsts) & BMSTS_RXACT))
+		; /* noop */
+
+	/*
+	 * Initialize the RX descriptor queue. Clear the TX descriptor queue.
+	 * Clear the RX and TX status queues. Enqueue the RX descriptor and
+	 * status entries to the MAC.
+	 */
+	for (i = 0; i < NUMRXDESC; i++) {
+		/* set buffer address */
+		(priv->rx_dq.base + i)->word1 = (uint32_t)NetRxPackets[i];
+
+		/* set buffer length, clear buffer index and NSOF */
+		(priv->rx_dq.base + i)->word2 = PKTSIZE_ALIGN;
+	}
+
+	memset(priv->tx_dq.base, 0,
+		(sizeof(struct tx_descriptor) * NUMTXDESC));
+	memset(priv->rx_sq.base, 0,
+		(sizeof(struct rx_status) * NUMRXDESC));
+	memset(priv->tx_sq.base, 0,
+		(sizeof(struct tx_status) * NUMTXDESC));
+
+	writel(NUMRXDESC, &mac->rxdqenq);
+	writel(NUMRXDESC, &mac->rxstsqenq);
+
+	/* Set the primary MAC address */
+	writel(AFP_IAPRIMARY, &mac->afp);
+	writel(mac_addr[0] | (mac_addr[1] << 8) |
+		(mac_addr[2] << 16) | (mac_addr[3] << 24),
+		&mac->indad);
+	writel(mac_addr[4] | (mac_addr[5] << 8), &mac->indad_upper);
+
+	/* Turn on RX and TX */
+	writel(RXCTL_IA0 | RXCTL_BA | RXCTL_SRXON |
+		RXCTL_RCRCA | RXCTL_MA, &mac->rxctl);
+	writel(TXCTL_STXON, &mac->txctl);
+
+	/* Dump data structures if we're debugging */
+	dump_dev(dev);
+	dump_rx_descriptor_queue(dev);
+	dump_rx_status_queue(dev);
+	dump_tx_descriptor_queue(dev);
+	dump_tx_status_queue(dev);
+
+	debug("-ep93xx_eth_open");
+
+	return 1;
+}
+
+/**
+ * Halt EP93xx MAC transmit and receive by clearing the TxCTL and RxCTL
+ * registers.
+ */
+static void ep93xx_eth_close(struct eth_device *dev)
+{
+	struct mac_regs *mac = GET_REGS(dev);
+
+	debug("+ep93xx_eth_close");
+
+	writel(0x00000000, &mac->rxctl);
+	writel(0x00000000, &mac->txctl);
+
+	debug("-ep93xx_eth_close");
+}
+
+/**
+ * Copy a frame of data from the MAC into the protocol layer for further
+ * processing.
+ */
+static int ep93xx_eth_rcv_packet(struct eth_device *dev)
+{
+	struct mac_regs *mac = GET_REGS(dev);
+	struct ep93xx_priv *priv = GET_PRIV(dev);
+	int len = -1;
+
+	debug("+ep93xx_eth_rcv_packet");
+
+	if (RX_STATUS_RFP(priv->rx_sq.current)) {
+		if (RX_STATUS_RWE(priv->rx_sq.current)) {
+			/*
+			 * We have a good frame. Extract the frame's length
+			 * from the current rx_status_queue entry, and copy
+			 * the frame's data into NetRxPackets[] of the
+			 * protocol stack. We track the total number of
+			 * bytes in the frame (nbytes_frame) which will be
+			 * used when we pass the data off to the protocol
+			 * layer via NetReceive().
+			 */
+			len = RX_STATUS_FRAME_LEN(priv->rx_sq.current);
+
+			NetReceive((uchar *)priv->rx_dq.current->word1,	len);
+
+			debug("reporting %d bytes...\n", len);
+		} else {
+			/* Do we have an erroneous packet? */
+			error("packet rx error, status %08X %08X",
+				priv->rx_sq.current->word1,
+				priv->rx_sq.current->word2);
+			dump_rx_descriptor_queue(dev);
+			dump_rx_status_queue(dev);
+		}
+
+		/*
+		 * Clear the associated status queue entry, and
+		 * increment our current pointers to the next RX
+		 * descriptor and status queue entries (making sure
+		 * we wrap properly).
+		 */
+		memset((void *)priv->rx_sq.current, 0,
+			sizeof(struct rx_status));
+
+		priv->rx_sq.current++;
+		if (priv->rx_sq.current >= priv->rx_sq.end)
+			priv->rx_sq.current = priv->rx_sq.base;
+
+		priv->rx_dq.current++;
+		if (priv->rx_dq.current >= priv->rx_dq.end)
+			priv->rx_dq.current = priv->rx_dq.base;
+
+		/*
+		 * Finally, return the RX descriptor and status entries
+		 * back to the MAC engine, and loop again, checking for
+		 * more descriptors to process.
+		 */
+		writel(1, &mac->rxdqenq);
+		writel(1, &mac->rxstsqenq);
+	} else {
+		len = 0;
+	}
+
+	debug("-ep93xx_eth_rcv_packet %d", len);
+	return len;
+}
+
+/**
+ * Send a block of data via ethernet.
+ */
+static int ep93xx_eth_send_packet(struct eth_device *dev,
+				volatile void * const packet, int const length)
+{
+	struct mac_regs *mac = GET_REGS(dev);
+	struct ep93xx_priv *priv = GET_PRIV(dev);
+	int ret = -1;
+
+	debug("+ep93xx_eth_send_packet");
+
+	/* Parameter check */
+	BUG_ON(packet == NULL);
+
+	/*
+	 * Initialize the TX descriptor queue with the new packet's info.
+	 * Clear the associated status queue entry. Enqueue the packet
+	 * to the MAC for transmission.
+	 */
+
+	/* set buffer address */
+	priv->tx_dq.current->word1 = (uint32_t)packet;
+
+	/* set buffer length and EOF bit */
+	priv->tx_dq.current->word2 = length | TX_DESC_EOF;
+
+	/* clear tx status */
+	priv->tx_sq.current->word1 = 0;
+
+	/* enqueue the TX descriptor */
+	writel(1, &mac->txdqenq);
+
+	/* wait for the frame to become processed */
+	while (!TX_STATUS_TXFP(priv->tx_sq.current))
+		; /* noop */
+
+	if (!TX_STATUS_TXWE(priv->tx_sq.current)) {
+		error("packet tx error, status %08X",
+			priv->tx_sq.current->word1);
+		dump_tx_descriptor_queue(dev);
+		dump_tx_status_queue(dev);
+
+		/* TODO: Add better error handling? */
+		goto eth_send_out;
+	}
+
+	ret = 0;
+	/* Fall through */
+
+eth_send_out:
+	debug("-ep93xx_eth_send_packet %d", ret);
+	return ret;
+}
+
+#if defined(CONFIG_MII)
+int ep93xx_miiphy_initialize(bd_t * const bd)
+{
+	miiphy_register("ep93xx_eth0", ep93xx_miiphy_read, ep93xx_miiphy_write);
+	return 0;
+}
+#endif
+
+/**
+ * Initialize the EP93xx MAC.  The MAC hardware is reset.  Buffers are
+ * allocated, if necessary, for the TX and RX descriptor and status queues,
+ * as well as for received packets.  The EP93XX MAC hardware is initialized.
+ * Transmit and receive operations are enabled.
+ */
+int ep93xx_eth_initialize(u8 dev_num, int base_addr)
+{
+	int ret = -1;
+	struct eth_device *dev;
+	struct ep93xx_priv *priv;
+
+	debug("+ep93xx_eth_initialize");
+
+	priv = malloc(sizeof(*priv));
+	if (!priv) {
+		error("malloc() failed");
+		goto eth_init_failed_0;
+	}
+	memset(priv, 0, sizeof(*priv));
+
+	priv->regs = (struct mac_regs *)base_addr;
+
+	priv->tx_dq.base = calloc(NUMTXDESC,
+				sizeof(struct tx_descriptor));
+	if (priv->tx_dq.base == NULL) {
+		error("calloc() failed");
+		goto eth_init_failed_1;
+	}
+
+	priv->tx_sq.base = calloc(NUMTXDESC,
+				sizeof(struct tx_status));
+	if (priv->tx_sq.base == NULL) {
+		error("calloc() failed");
+		goto eth_init_failed_2;
+	}
+
+	priv->rx_dq.base = calloc(NUMRXDESC,
+				sizeof(struct rx_descriptor));
+	if (priv->rx_dq.base == NULL) {
+		error("calloc() failed");
+		goto eth_init_failed_3;
+	}
+
+	priv->rx_sq.base = calloc(NUMRXDESC,
+				sizeof(struct rx_status));
+	if (priv->rx_sq.base == NULL) {
+		error("calloc() failed");
+		goto eth_init_failed_4;
+	}
+
+	dev = malloc(sizeof *dev);
+	if (dev == NULL) {
+		error("malloc() failed");
+		goto eth_init_failed_5;
+	}
+	memset(dev, 0, sizeof *dev);
+
+	dev->iobase = base_addr;
+	dev->priv = priv;
+	dev->init = ep93xx_eth_open;
+	dev->halt = ep93xx_eth_close;
+	dev->send = ep93xx_eth_send_packet;
+	dev->recv = ep93xx_eth_rcv_packet;
+
+	sprintf(dev->name, "ep93xx_eth-%hu", dev_num);
+
+	eth_register(dev);
+
+	/* Done! */
+	ret = 1;
+	goto eth_init_done;
+
+eth_init_failed_5:
+	free(priv->rx_sq.base);
+	/* Fall through */
+
+eth_init_failed_4:
+	free(priv->rx_dq.base);
+	/* Fall through */
+
+eth_init_failed_3:
+	free(priv->tx_sq.base);
+	/* Fall through */
+
+eth_init_failed_2:
+	free(priv->tx_dq.base);
+	/* Fall through */
+
+eth_init_failed_1:
+	free(priv);
+	/* Fall through */
+
+eth_init_failed_0:
+	/* Fall through */
+
+eth_init_done:
+	debug("-ep93xx_eth_initialize %d", ret);
+	return ret;
+}
+
+#if defined(CONFIG_MII)
+
+/**
+ * Maximum MII address we support
+ */
+#define MII_ADDRESS_MAX			31
+
+/**
+ * Maximum MII register address we support
+ */
+#define MII_REGISTER_MAX		31
+
+/**
+ * Read a 16-bit value from an MII register.
+ */
+static int ep93xx_miiphy_read(char * const dev, unsigned char const addr,
+			unsigned char const reg, unsigned short * const value)
+{
+	struct mac_regs *mac = (struct mac_regs *)MAC_BASE;
+	int ret = -1;
+	uint32_t self_ctl;
+
+	debug("+ep93xx_miiphy_read");
+
+	/* Parameter checks */
+	BUG_ON(dev == NULL);
+	BUG_ON(addr > MII_ADDRESS_MAX);
+	BUG_ON(reg > MII_REGISTER_MAX);
+	BUG_ON(value == NULL);
+
+	/*
+	 * Save the current SelfCTL register value.  Set MAC to suppress
+	 * preamble bits.  Wait for any previous MII command to complete
+	 * before issuing the new command.
+	 */
+	self_ctl = readl(&mac->selfctl);
+#if defined(CONFIG_MII_SUPPRESS_PREAMBLE)
+	writel(self_ctl & ~(1 << 8), &mac->selfctl);
+#endif	/* defined(CONFIG_MII_SUPPRESS_PREAMBLE) */
+
+	while (readl(&mac->miists) & MIISTS_BUSY)
+		; /* noop */
+
+	/*
+	 * Issue the MII 'read' command.  Wait for the command to complete.
+	 * Read the MII data value.
+	 */
+	writel(MIICMD_OPCODE_READ | ((uint32_t)addr << 5) | (uint32_t)reg,
+		&mac->miicmd);
+	while (readl(&mac->miists) & MIISTS_BUSY)
+		; /* noop */
+
+	*value = (unsigned short)readl(&mac->miidata);
+
+	/* Restore the saved SelfCTL value and return. */
+	writel(self_ctl, &mac->selfctl);
+
+	ret = 0;
+	/* Fall through */
+
+	debug("-ep93xx_miiphy_read");
+	return ret;
+}
+
+/**
+ * Write a 16-bit value to an MII register.
+ */
+static int ep93xx_miiphy_write(char * const dev, unsigned char const addr,
+			unsigned char const reg, unsigned short const value)
+{
+	struct mac_regs *mac = (struct mac_regs *)MAC_BASE;
+	int ret = -1;
+	uint32_t self_ctl;
+
+	debug("+ep93xx_miiphy_write");
+
+	/* Parameter checks */
+	BUG_ON(dev == NULL);
+	BUG_ON(addr > MII_ADDRESS_MAX);
+	BUG_ON(reg > MII_REGISTER_MAX);
+
+	/*
+	 * Save the current SelfCTL register value.  Set MAC to suppress
+	 * preamble bits.  Wait for any previous MII command to complete
+	 * before issuing the new command.
+	 */
+	self_ctl = readl(&mac->selfctl);
+#if defined(CONFIG_MII_SUPPRESS_PREAMBLE)
+	writel(self_ctl & ~(1 << 8), &mac->selfctl);
+#endif	/* defined(CONFIG_MII_SUPPRESS_PREAMBLE) */
+
+	while (readl(&mac->miists) & MIISTS_BUSY)
+		; /* noop */
+
+	/* Issue the MII 'write' command.  Wait for the command to complete. */
+	writel((uint32_t)value, &mac->miidata);
+	writel(MIICMD_OPCODE_WRITE | ((uint32_t)addr << 5) | (uint32_t)reg,
+		&mac->miicmd);
+	while (readl(&mac->miists) & MIISTS_BUSY)
+		; /* noop */
+
+	/* Restore the saved SelfCTL value and return. */
+	writel(self_ctl, &mac->selfctl);
+
+	ret = 0;
+	/* Fall through */
+
+	debug("-ep93xx_miiphy_write");
+	return ret;
+}
+#endif	/* defined(CONFIG_MII) */