[ADS5121] Support for the ADS5121 board

The following MPC5121e subsystems are supported:

- low-level CPU init
- NOR Boot Flash (common CFI driver)
- DDR SDRAM
- FEC
- I2C
- Watchdog

Signed-off-by: Grzegorz Bernacki <gjb@semihalf.com>
Signed-off-by: Rafal Jaworowski <raj@semihalf.com>
Signed-off-by: Jan Wrobel <wrr@semihalf.com>

1 files changed, 431 insertions, 0 deletions

diff --git a/cpu/mpc512x/i2c.c b/cpu/mpc512x/i2c.c
new file mode 100644
index 0000000..00e28d6
--- /dev/null
+++ b/cpu/mpc512x/i2c.c
@@ -0,0 +1,431 @@
+/*
+ * (C) Copyright 2003 - 2007
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * Based on the MPC5xxx code.
+ */
+
+#include <common.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#ifdef CONFIG_HARD_I2C
+
+#include <mpc512x.h>
+#include <i2c.h>
+
+#define immr ((immap_t *)CFG_IMMR)
+
+/* by default set I2C bus 0 active */
+static unsigned int bus_num = 0;
+
+#define I2C_TIMEOUT	100
+#define I2C_RETRIES	3
+
+struct mpc512x_i2c_tap {
+	int scl2tap;
+	int tap2tap;
+};
+
+static int  mpc_reg_in(volatile u32 *reg);
+static void mpc_reg_out(volatile u32 *reg, int val, int mask);
+static int  wait_for_bb(void);
+static int  wait_for_pin(int *status);
+static int  do_address(uchar chip, char rdwr_flag);
+static int  send_bytes(uchar chip, char *buf, int len);
+static int  receive_bytes(uchar chip, char *buf, int len);
+static int  mpc_get_fdr(int);
+
+static int mpc_reg_in (volatile u32 *reg)
+{
+	int ret = *reg >> 24;
+	__asm__ __volatile__ ("eieio");
+	return ret;
+}
+
+static void mpc_reg_out (volatile u32 *reg, int val, int mask)
+{
+	int tmp;
+
+	if (!mask) {
+		*reg = val << 24;
+	} else {
+		tmp = mpc_reg_in (reg);
+		*reg = ((tmp & ~mask) | (val & mask)) << 24;
+	}
+	__asm__ __volatile__ ("eieio");
+
+	return;
+}
+
+static int wait_for_bb (void)
+{
+	i2c512x_dev_t *regs = &immr->i2c.dev[bus_num];
+	int timeout = I2C_TIMEOUT;
+	int status;
+
+	status = mpc_reg_in (&regs->msr);
+
+	while (timeout-- && (status & I2C_BB)) {
+		volatile int temp;
+		mpc_reg_out (&regs->mcr, I2C_STA, I2C_STA);
+		temp = mpc_reg_in (&regs->mdr);
+		mpc_reg_out (&regs->mcr, 0, I2C_STA);
+		mpc_reg_out (&regs->mcr, 0, 0);
+		mpc_reg_out (&regs->mcr, I2C_EN, 0);
+
+		udelay (1000);
+		status = mpc_reg_in (&regs->msr);
+	}
+
+	return (status & I2C_BB);
+}
+
+static int wait_for_pin (int *status)
+{
+	i2c512x_dev_t *regs = &immr->i2c.dev[bus_num];
+	int timeout = I2C_TIMEOUT;
+
+	*status = mpc_reg_in (&regs->msr);
+
+	while (timeout-- && !(*status & I2C_IF)) {
+		udelay (1000);
+		*status = mpc_reg_in (&regs->msr);
+	}
+
+	if (!(*status & I2C_IF)) {
+		return -1;
+	}
+
+	mpc_reg_out (&regs->msr, 0, I2C_IF);
+
+	return 0;
+}
+
+static int do_address (uchar chip, char rdwr_flag)
+{
+	i2c512x_dev_t *regs = &immr->i2c.dev[bus_num];
+	int status;
+
+	chip <<= 1;
+
+	if (rdwr_flag) {
+		chip |= 1;
+	}
+
+	mpc_reg_out (&regs->mcr, I2C_TX, I2C_TX);
+	mpc_reg_out (&regs->mdr, chip, 0);
+
+	if (wait_for_pin (&status)) {
+		return -2;
+	}
+
+	if (status & I2C_RXAK) {
+		return -3;
+	}
+
+	return 0;
+}
+
+static int send_bytes (uchar chip, char *buf, int len)
+{
+	i2c512x_dev_t *regs = &immr->i2c.dev[bus_num];
+	int wrcount;
+	int status;
+
+	for (wrcount = 0; wrcount < len; ++wrcount) {
+
+		mpc_reg_out (&regs->mdr, buf[wrcount], 0);
+
+		if (wait_for_pin (&status)) {
+			break;
+		}
+
+		if (status & I2C_RXAK) {
+			break;
+		}
+
+	}
+
+	return !(wrcount == len);
+}
+
+static int receive_bytes (uchar chip, char *buf, int len)
+{
+	i2c512x_dev_t *regs = &immr->i2c.dev[bus_num];
+	int dummy   = 1;
+	int rdcount = 0;
+	int status;
+	int i;
+
+	mpc_reg_out (&regs->mcr, 0, I2C_TX);
+
+	for (i = 0; i < len; ++i) {
+		buf[rdcount] = mpc_reg_in (&regs->mdr);
+
+		if (dummy) {
+			dummy = 0;
+		} else {
+			rdcount++;
+		}
+
+		if (wait_for_pin (&status)) {
+			return -4;
+		}
+	}
+
+	mpc_reg_out (&regs->mcr, I2C_TXAK, I2C_TXAK);
+	buf[rdcount++] = mpc_reg_in (&regs->mdr);
+
+	if (wait_for_pin (&status)) {
+		return -5;
+	}
+
+	mpc_reg_out (&regs->mcr, 0, I2C_TXAK);
+
+	return 0;
+}
+
+/**************** I2C API ****************/
+
+void i2c_init (int speed, int saddr)
+{
+	int i;
+	for(i = 0; i < I2C_BUS_CNT; i++){
+		i2c512x_dev_t *regs = &immr->i2c.dev[i];
+		mpc_reg_out (&regs->mcr, 0, 0);
+
+		/* Set clock */
+		mpc_reg_out (&regs->mfdr, mpc_get_fdr (speed), 0);
+		mpc_reg_out (&regs->madr, saddr << 1, 0);
+
+		/* Enable module */
+		mpc_reg_out (&regs->mcr, I2C_EN, I2C_INIT_MASK);
+		mpc_reg_out (&regs->msr, 0, I2C_IF);
+	}
+
+	/* Disable interrupts */
+	immr->i2c.icr = 0;
+	/* Turn off filters */
+	immr->i2c.mifr = 0;
+	return;
+}
+
+static int mpc_get_fdr (int speed)
+{
+	static int fdr = -1;
+
+	if (fdr == -1) {
+		ulong best_speed = 0;
+		ulong divider;
+		ulong ipb, scl;
+		ulong bestmatch = 0xffffffffUL;
+		int best_i = 0, best_j = 0, i, j;
+		int SCL_Tap[] = { 9, 10, 12, 15, 5, 6, 7, 8};
+		struct mpc512x_i2c_tap scltap[] = {
+			{4, 1},
+			{4, 2},
+			{6, 4},
+			{6, 8},
+			{14, 16},
+			{30, 32},
+			{62, 64},
+			{126, 128}
+		};
+
+		ipb = gd->ipb_clk;
+		for (i = 7; i >= 0; i--) {
+			for (j = 7; j >= 0; j--) {
+				scl = 2 * (scltap[j].scl2tap +
+					   (SCL_Tap[i] - 1) * scltap[j].tap2tap
+					   + 2);
+				if (ipb <= speed*scl) {
+					if ((speed*scl - ipb) < bestmatch) {
+						bestmatch = speed*scl - ipb;
+						best_i = i;
+						best_j = j;
+						best_speed = ipb/scl;
+					}
+				}
+			}
+		}
+		divider = (best_i & 3) | ((best_i & 4) << 3) | (best_j << 2);
+		if (gd->flags & GD_FLG_RELOC) {
+			fdr = divider;
+		} else {
+			debug("%ld kHz, \n", best_speed / 1000);
+			return divider;
+		}
+	}
+
+	return fdr;
+}
+
+int i2c_probe (uchar chip)
+{
+	i2c512x_dev_t *regs = &immr->i2c.dev[bus_num];
+	int i;
+
+	for (i = 0; i < I2C_RETRIES; i++) {
+		mpc_reg_out (&regs->mcr, I2C_STA, I2C_STA);
+
+		if (! do_address (chip, 0)) {
+			mpc_reg_out (&regs->mcr, 0, I2C_STA);
+			udelay (500);
+			break;
+		}
+
+		mpc_reg_out (&regs->mcr, 0, I2C_STA);
+		udelay (500);
+	}
+
+	return (i == I2C_RETRIES);
+}
+
+int i2c_read (uchar chip, uint addr, int alen, uchar *buf, int len)
+{
+	char xaddr[4];
+	i2c512x_dev_t *regs = &immr->i2c.dev[bus_num];
+	int ret = -1;
+
+	xaddr[0] = (addr >> 24) & 0xFF;
+	xaddr[1] = (addr >> 16) & 0xFF;
+	xaddr[2] = (addr >>  8) & 0xFF;
+	xaddr[3] =  addr	& 0xFF;
+
+	if (wait_for_bb ()) {
+		printf ("i2c_read: bus is busy\n");
+		goto Done;
+	}
+
+	mpc_reg_out (&regs->mcr, I2C_STA, I2C_STA);
+	if (do_address (chip, 0)) {
+		printf ("i2c_read: failed to address chip\n");
+		goto Done;
+	}
+
+	if (send_bytes (chip, &xaddr[4-alen], alen)) {
+		printf ("i2c_read: send_bytes failed\n");
+		goto Done;
+	}
+
+	mpc_reg_out (&regs->mcr, I2C_RSTA, I2C_RSTA);
+	if (do_address (chip, 1)) {
+		printf ("i2c_read: failed to address chip\n");
+		goto Done;
+	}
+
+	if (receive_bytes (chip, (char *)buf, len)) {
+		printf ("i2c_read: receive_bytes failed\n");
+		goto Done;
+	}
+
+	ret = 0;
+Done:
+	mpc_reg_out (&regs->mcr, 0, I2C_STA);
+	return ret;
+}
+
+int i2c_write (uchar chip, uint addr, int alen, uchar *buf, int len)
+{
+	char xaddr[4];
+	i2c512x_dev_t *regs = &immr->i2c.dev[bus_num];
+	int ret = -1;
+
+	xaddr[0] = (addr >> 24) & 0xFF;
+	xaddr[1] = (addr >> 16) & 0xFF;
+	xaddr[2] = (addr >>  8) & 0xFF;
+	xaddr[3] =  addr	& 0xFF;
+
+	if (wait_for_bb ()) {
+		printf ("i2c_write: bus is busy\n");
+		goto Done;
+	}
+
+	mpc_reg_out (&regs->mcr, I2C_STA, I2C_STA);
+	if (do_address (chip, 0)) {
+		printf ("i2c_write: failed to address chip\n");
+		goto Done;
+	}
+
+	if (send_bytes (chip, &xaddr[4-alen], alen)) {
+		printf ("i2c_write: send_bytes failed\n");
+		goto Done;
+	}
+
+	if (send_bytes (chip, (char *)buf, len)) {
+		printf ("i2c_write: send_bytes failed\n");
+		goto Done;
+	}
+
+	ret = 0;
+Done:
+	mpc_reg_out (&regs->mcr, 0, I2C_STA);
+	return ret;
+}
+
+uchar i2c_reg_read (uchar chip, uchar reg)
+{
+	uchar buf;
+
+	i2c_read (chip, reg, 1, &buf, 1);
+
+	return buf;
+}
+
+void i2c_reg_write (uchar chip, uchar reg, uchar val)
+{
+	i2c_write (chip, reg, 1, &val, 1);
+
+	return;
+}
+
+
+int i2c_set_bus_num (unsigned int bus)
+{
+	if (bus >= I2C_BUS_CNT) {
+		return -1;
+	}
+	bus_num = bus;
+
+	return 0;
+}
+
+unsigned int i2c_get_bus_num (void)
+{
+	return bus_num;
+}
+
+/* TODO */
+unsigned int i2c_get_bus_speed (void)
+{
+	return -1;
+}
+
+int i2c_set_bus_speed (unsigned int speed)
+{
+	if (speed != CFG_I2C_SPEED)
+		return -1;
+
+	return 0;
+}
+
+#endif	/* CONFIG_HARD_I2C */