armv7: Move Exynos from 'cpu' to 'soc'.

The Exynos family and most ARM products are SoC, not just CPU.

We used to put ARM code in src/cpu to avoid polluting the code base for what was
essentially an experiment at the time. Now that it's past the experimental phase
and we're going to see more SoCs (including intel/baytrail) in coreboot.

Change-Id: I5ea1f822664244edf5f77087bc8018d7c535f81c
Reviewed-on: https://chromium-review.googlesource.com/170891
Tested-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Ronald Minnich <rminnich@chromium.org>
Commit-Queue: Hung-Te Lin <hungte@chromium.org>
(cherry picked from commit c8bb8fe0b20be37465f93c738d80e7e43033670a)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6739
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

1 files changed, 403 insertions, 0 deletions

diff --git a/src/soc/samsung/exynos5250/i2c.c b/src/soc/samsung/exynos5250/i2c.c
new file mode 100644
index 0000000000..e83ab57014
--- /dev/null
+++ b/src/soc/samsung/exynos5250/i2c.c
@@ -0,0 +1,403 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * (C) Copyright 2002
+ * David Mueller, ELSOFT AG, d.mueller@elsoft.ch
+ *
+ * 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; version 2 of the License.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <console/console.h>
+#include <delay.h>
+#include <arch/io.h>
+#include <device/i2c.h>
+#include "clk.h"
+#include "i2c.h"
+
+#define I2C_WRITE	0
+#define I2C_READ	1
+
+#define I2C_OK		0
+#define I2C_NOK		1
+#define I2C_NACK	2
+#define I2C_NOK_LA	3	/* Lost arbitration */
+#define I2C_NOK_TOUT	4	/* time out */
+
+#define I2CSTAT_BSY	0x20	/* Busy bit */
+#define I2CSTAT_NACK	0x01	/* Nack bit */
+#define I2CCON_ACKGEN	0x80	/* Acknowledge generation */
+#define I2CCON_IRPND	0x10	/* Interrupt pending bit */
+#define I2C_MODE_MT	0xC0	/* Master Transmit Mode */
+#define I2C_MODE_MR	0x80	/* Master Receive Mode */
+#define I2C_START_STOP	0x20	/* START / STOP */
+#define I2C_TXRX_ENA	0x10	/* I2C Tx/Rx enable */
+
+/* The timeouts we live by */
+enum {
+	I2C_XFER_TIMEOUT_MS	= 35,	/* xfer to complete */
+	I2C_INIT_TIMEOUT_MS	= 1000,	/* bus free on init */
+	I2C_IDLE_TIMEOUT_MS	= 100,	/* waiting for bus idle */
+	I2C_STOP_TIMEOUT_US	= 200,	/* waiting for stop events */
+};
+
+static struct s3c24x0_i2c_bus i2c_buses[] = {
+	{
+		.bus_num = 0,
+		.regs = (struct s3c24x0_i2c *)0x12c60000,
+		.periph_id = PERIPH_ID_I2C0,
+	},
+	{
+		.bus_num = 1,
+		.regs = (struct s3c24x0_i2c *)0x12c70000,
+		.periph_id = PERIPH_ID_I2C1,
+	},
+	{
+		.bus_num = 2,
+		.regs = (struct s3c24x0_i2c *)0x12c80000,
+		.periph_id = PERIPH_ID_I2C2,
+	},
+	{
+		.bus_num = 3,
+		.regs = (struct s3c24x0_i2c *)0x12c90000,
+		.periph_id = PERIPH_ID_I2C3,
+	},
+	{
+		.bus_num = 4,
+		.regs = (struct s3c24x0_i2c *)0x12ca0000,
+		.periph_id = PERIPH_ID_I2C4,
+	},
+	{
+		.bus_num = 5,
+		.regs = (struct s3c24x0_i2c *)0x12cb0000,
+		.periph_id = PERIPH_ID_I2C5,
+	},
+	{
+		.bus_num = 6,
+		.regs = (struct s3c24x0_i2c *)0x12cc0000,
+		.periph_id = PERIPH_ID_I2C6,
+	},
+	{
+		.bus_num = 7,
+		.regs = (struct s3c24x0_i2c *)0x12cd0000,
+		.periph_id = PERIPH_ID_I2C7,
+	},
+};
+
+static int WaitForXfer(struct s3c24x0_i2c *i2c)
+{
+	int i;
+
+	i = I2C_XFER_TIMEOUT_MS * 20;
+	while (!(readl(&i2c->iiccon) & I2CCON_IRPND)) {
+		if (i == 0) {
+			printk(BIOS_ERR, "%s: i2c xfer timeout\n", __func__);
+			return I2C_NOK_TOUT;
+		}
+		udelay(50);
+		i--;
+	}
+
+	return I2C_OK;
+}
+
+static int IsACK(struct s3c24x0_i2c *i2c)
+{
+	return !(readl(&i2c->iicstat) & I2CSTAT_NACK);
+}
+
+static void ReadWriteByte(struct s3c24x0_i2c *i2c)
+{
+	uint32_t x;
+
+	x = readl(&i2c->iiccon);
+	writel(x & ~I2CCON_IRPND, &i2c->iiccon);
+}
+
+static void i2c_ch_init(struct s3c24x0_i2c_bus *bus, int speed, int slaveadd)
+{
+	unsigned long freq, pres = 16, div;
+	unsigned long val;
+
+	freq = clock_get_periph_rate(bus->periph_id);
+	/* calculate prescaler and divisor values */
+	if ((freq / pres / (16 + 1)) > speed)
+		/* set prescaler to 512 */
+		pres = 512;
+
+	div = 0;
+
+	while ((freq / pres / (div + 1)) > speed)
+		div++;
+
+	/* set prescaler, divisor according to freq, also set ACKGEN, IRQ */
+	val = (div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0);
+	writel(val, &bus->regs->iiccon);
+
+	/* init to SLAVE RECEIVE mode and clear I2CADDn */
+	writel(0, &bus->regs->iicstat);
+	writel(slaveadd, &bus->regs->iicadd);
+	/* program Master Transmit (and implicit STOP) */
+	writel(I2C_MODE_MT | I2C_TXRX_ENA, &bus->regs->iicstat);
+}
+
+/*
+ * MULTI BUS I2C support
+ */
+static void i2c_bus_init(struct s3c24x0_i2c_bus *bus, int speed, int slaveadd)
+{
+	i2c_ch_init(bus, speed, slaveadd);
+}
+
+/*
+ * Verify the whether I2C ACK was received or not
+ *
+ * @param i2c	pointer to I2C register base
+ * @param buf	array of data
+ * @param len	length of data
+ * return	I2C_OK when transmission done
+ *		I2C_NACK otherwise
+ */
+static int i2c_send_verify(struct s3c24x0_i2c *i2c, unsigned char buf[],
+			   unsigned char len)
+{
+	int i, result = I2C_OK;
+
+	if (IsACK(i2c)) {
+		for (i = 0; (i < len) && (result == I2C_OK); i++) {
+			writel(buf[i], &i2c->iicds);
+			ReadWriteByte(i2c);
+			result = WaitForXfer(i2c);
+			if (result == I2C_OK && !IsACK(i2c))
+				result = I2C_NACK;
+		}
+	} else {
+		result = I2C_NACK;
+	}
+
+	return result;
+}
+
+void i2c_init(unsigned bus_num, int speed, int slaveadd)
+{
+	struct s3c24x0_i2c_bus *i2c;
+	int i;
+
+	i2c = &i2c_buses[bus_num];
+	i2c_bus_init(i2c, speed, slaveadd);
+
+	/* wait for some time to give previous transfer a chance to finish */
+	i = I2C_INIT_TIMEOUT_MS * 20;
+	while ((readl(&i2c->regs->iicstat) & I2CSTAT_BSY) && (i > 0)) {
+		udelay(50);
+		i--;
+	}
+
+	i2c_ch_init(i2c, speed, slaveadd);
+}
+
+/*
+ * Send a STOP event and wait for it to have completed
+ *
+ * @param mode	If it is a master transmitter or receiver
+ * @return I2C_OK if the line became idle before timeout I2C_NOK_TOUT otherwise
+ */
+static int i2c_send_stop(struct s3c24x0_i2c *i2c, int mode)
+{
+	int timeout;
+
+	/* Setting the STOP event to fire */
+	writel(mode | I2C_TXRX_ENA, &i2c->iicstat);
+	ReadWriteByte(i2c);
+
+	/* Wait for the STOP to send and the bus to go idle */
+	for (timeout = I2C_STOP_TIMEOUT_US; timeout > 0; timeout -= 5) {
+		if (!(readl(&i2c->iicstat) & I2CSTAT_BSY))
+			return I2C_OK;
+		udelay(5);
+	}
+
+	return I2C_NOK_TOUT;
+}
+
+/*
+ * cmd_type is 0 for write, 1 for read.
+ *
+ * addr_len can take any value from 0-255, it is only limited
+ * by the char, we could make it larger if needed. If it is
+ * 0 we skip the address write cycle.
+ */
+static int i2c_transfer(struct s3c24x0_i2c *i2c,
+			unsigned char cmd_type,
+			unsigned char chip,
+			unsigned char addr[],
+			unsigned char addr_len,
+			unsigned char data[],
+			unsigned short data_len)
+{
+	int i, result, stop_bit_result;
+	uint32_t x;
+
+	if (data == 0 || data_len == 0) {
+		/* Don't support data transfer of no length or to address 0 */
+		printk(BIOS_ERR, "i2c_transfer: bad call\n");
+		return I2C_NOK;
+	}
+
+	/* Check I2C bus idle */
+	i = I2C_IDLE_TIMEOUT_MS * 20;
+	while ((readl(&i2c->iicstat) & I2CSTAT_BSY) && (i > 0)) {
+		udelay(50);
+		i--;
+	}
+
+	if (readl(&i2c->iicstat) & I2CSTAT_BSY) {
+		printk(BIOS_ERR, "%s: bus busy\n", __func__);
+		return I2C_NOK_TOUT;
+	}
+
+	x = readl(&i2c->iiccon);
+	writel(x | I2CCON_ACKGEN, &i2c->iiccon);
+
+	if (addr && addr_len) {
+		writel(chip, &i2c->iicds);
+		/* send START */
+		writel(I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP,
+			&i2c->iicstat);
+		if (WaitForXfer(i2c) == I2C_OK)
+			result = i2c_send_verify(i2c, addr, addr_len);
+		else
+			result = I2C_NACK;
+	} else
+		result = I2C_NACK;
+
+	switch (cmd_type) {
+	case I2C_WRITE:
+		if (result == I2C_OK)
+			result = i2c_send_verify(i2c, data, data_len);
+		else {
+			writel(chip, &i2c->iicds);
+			/* send START */
+			writel(I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP,
+				&i2c->iicstat);
+			if (WaitForXfer(i2c) == I2C_OK)
+				result = i2c_send_verify(i2c, data, data_len);
+		}
+
+		if (result == I2C_OK)
+			result = WaitForXfer(i2c);
+
+		stop_bit_result = i2c_send_stop(i2c, I2C_MODE_MT);
+		break;
+
+	case I2C_READ:
+	{
+		int was_ok = (result == I2C_OK);
+
+		writel(chip, &i2c->iicds);
+		/* resend START */
+		writel(I2C_MODE_MR | I2C_TXRX_ENA |
+					I2C_START_STOP, &i2c->iicstat);
+		ReadWriteByte(i2c);
+		result = WaitForXfer(i2c);
+
+		if (was_ok || IsACK(i2c)) {
+			i = 0;
+			while ((i < data_len) && (result == I2C_OK)) {
+				/* disable ACK for final READ */
+				if (i == data_len - 1) {
+					x = readl(&i2c->iiccon) & ~I2CCON_ACKGEN;
+					writel(x, &i2c->iiccon);
+				}
+				ReadWriteByte(i2c);
+				result = WaitForXfer(i2c);
+				data[i] = readl(&i2c->iicds);
+				i++;
+			}
+		} else {
+			result = I2C_NACK;
+		}
+
+		stop_bit_result = i2c_send_stop(i2c, I2C_MODE_MR);
+		break;
+	}
+
+	default:
+		printk(BIOS_ERR, "i2c_transfer: bad call\n");
+		result = stop_bit_result = I2C_NOK;
+		break;
+	}
+
+	/*
+	 * If the transmission went fine, then only the stop bit was left to
+	 * fail.  Otherwise, the real failure we're interested in came before
+	 * that, during the actual transmission.
+	 */
+	return (result == I2C_OK) ? stop_bit_result : result;
+}
+
+int i2c_read(unsigned bus, unsigned chip, unsigned addr,
+		unsigned alen, uint8_t *buf, unsigned len)
+{
+	struct s3c24x0_i2c_bus *i2c;
+	unsigned char xaddr[4];
+	int ret;
+
+	if (alen > 4) {
+		printk(BIOS_ERR, "I2C read: addr len %d not supported\n", alen);
+		return 1;
+	}
+
+	if (alen > 0) {
+		xaddr[0] = (addr >> 24) & 0xFF;
+		xaddr[1] = (addr >> 16) & 0xFF;
+		xaddr[2] = (addr >> 8) & 0xFF;
+		xaddr[3] = addr & 0xFF;
+	}
+
+	i2c = &i2c_buses[bus];
+	ret = i2c_transfer(i2c->regs, I2C_READ, chip << 1, &xaddr[4 - alen],
+			   alen, buf, len);
+	if (ret) {
+		printk(BIOS_ERR, "I2c read: failed %d\n", ret);
+		return 1;
+	}
+	return 0;
+}
+
+int i2c_write(unsigned bus, unsigned chip, unsigned addr,
+		unsigned alen, const uint8_t *buf, unsigned len)
+{
+	struct s3c24x0_i2c_bus *i2c;
+	unsigned char xaddr[4];
+	int ret;
+
+	if (alen > 4) {
+		printk(BIOS_ERR, "I2C write: addr len %d not supported\n",
+				alen);
+		return 1;
+	}
+
+	if (alen > 0) {
+		xaddr[0] = (addr >> 24) & 0xFF;
+		xaddr[1] = (addr >> 16) & 0xFF;
+		xaddr[2] = (addr >> 8) & 0xFF;
+		xaddr[3] = addr & 0xFF;
+	}
+
+	i2c = &i2c_buses[bus];
+	ret = i2c_transfer(i2c->regs, I2C_WRITE, chip << 1, &xaddr[4 - alen],
+			   alen, (void *)buf, len);
+
+	return ret != 0;
+}