rk3288: add i2c

BUG=chrome-os-partner:29778
TEST=Build coreboot

Change-Id: I23af280764eb28d3f6b215ab32553fe42ee73272
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: abf5c14c8b32573107d2a1c73a752e740264db7e
Original-Change-Id: I46257cc71cc3cd1e867edf589ddf09f7990d6784
Original-Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Original-Signed-off-by: huang lin <hl@rock-chips.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/209462
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-by: David Hendricks <dhendrix@chromium.org>
Original-Commit-Queue: Julius Werner <jwerner@chromium.org>
Reviewed-on: http://review.coreboot.org/8863
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)

2 files changed, 279 insertions, 0 deletions

diff --git a/src/soc/rockchip/rk3288/Makefile.inc b/src/soc/rockchip/rk3288/Makefile.inc
index 7d5b3a5767..e6f6336c39 100644
--- a/src/soc/rockchip/rk3288/Makefile.inc
+++ b/src/soc/rockchip/rk3288/Makefile.inc
@@ -34,6 +34,7 @@ romstage-y += cbmem.c
 romstage-y += timer.c
 romstage-y += monotonic_timer.c
 romstage-$(CONFIG_DRIVERS_UART) += uart.c
+romstage-y += i2c.c
 romstage-y += clock.c
 romstage-y += spi.c
 romstage-y += media.c
@@ -41,6 +42,7 @@ romstage-y += media.c
 ramstage-y += cbmem.c
 ramstage-y += timer.c
 ramstage-y += monotonic_timer.c
+ramstage-y += i2c.c
 ramstage-y += clock.c
 ramstage-y += spi.c
 ramstage-y += media.c
diff --git a/src/soc/rockchip/rk3288/i2c.c b/src/soc/rockchip/rk3288/i2c.c
new file mode 100755
index 0000000000..80ad253e59
--- /dev/null
+++ b/src/soc/rockchip/rk3288/i2c.c
@@ -0,0 +1,277 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2014 Rockchip Inc.
+ *
+ * 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 <arch/io.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include <delay.h>
+#include <cbfs.h>
+#include <string.h>
+#include <device/i2c.h>
+
+#include "addressmap.h"
+#include "grf.h"
+#include "cpu.h"
+#define RETRY_COUNT	3
+/* 100000us = 100ms */
+#define I2C_TIMEOUT_US	100000
+#define I2C_BUS_MAX 6
+#define I2C_NOACK	2
+#define I2C_TIMEOUT	3
+
+#define i2c_info(x...) do {if (0) printk(BIOS_DEBUG, x); } while (0)
+
+struct rk3288_i2c_regs {
+	u32 i2c_con;
+	u32 i2c_clkdiv;
+	u32 i2c_mrxaddr;
+	u32 i2c_mrxraddr;
+	u32 i2c_mtxcnt;
+	u32 i2c_mrxcnt;
+	u32 i2c_ien;
+	u32 i2c_ipd;
+	u32 i2c_fcnt;
+	u32 reserved0[(0x100 - 0x24) / 4];
+	u32 txdata[8];
+	u32 reserved1[(0x200 - 0x120) / 4];
+	u32 rxdata[8];
+};
+
+struct rk3288_i2c_regs *i2c_bus[] = {
+	(struct rk3288_i2c_regs *)0xff650000,
+	(struct rk3288_i2c_regs *)0xff140000,
+	(struct rk3288_i2c_regs *)0xff660000,
+	(struct rk3288_i2c_regs *)0xff150000,
+	(struct rk3288_i2c_regs *)0xff160000,
+	(struct rk3288_i2c_regs *)0xff170000,
+};
+
+/* Con register bits. */
+#define I2C_ACT2NAK			(1<<6)
+#define I2C_NAK				(1<<5)
+#define I2C_STOP				(1<<4)
+#define I2C_START			(1<<3)
+#define I2C_MODE_TX			(0<<1)
+#define I2C_MODE_TRX		(1<<1)
+#define I2C_MODE_RX			(2<<1)
+#define I2C_EN				(1<<0)
+
+#define I2C_8BIT	(1<<24)
+#define I2C_16BIT	(3<<24)
+#define I2C_24BIT	(7<<24)
+
+/* Mtxcnt register bits. */
+#define I2C_CNT(cnt)		((cnt) & 0x3F)
+
+#define I2C_NAKRCVI	(1<<6)
+#define I2C_STOPI	(1<<5)
+#define I2C_STARTI	(1<<4)
+#define I2C_MBRFI	(1<<3)
+#define I2C_MBTFI	(1<<2)
+#define I2C_BRFI	(1<<1)
+#define I2C_BTFI	(1<<0)
+#define I2C_CLEANI	0x7F
+
+static int i2c_send_start(struct rk3288_i2c_regs *reg_addr)
+{
+	int res = 0;
+	int timeout = I2C_TIMEOUT_US;
+
+	i2c_info("I2c Start::Send Start bit\n");
+	writel(I2C_CLEANI, &reg_addr->i2c_ipd);
+	writel(I2C_EN | I2C_START, &reg_addr->i2c_con);
+	while (timeout--) {
+		if (readl(&reg_addr->i2c_ipd) & I2C_STARTI)
+			break;
+		udelay(1);
+	}
+
+	if (timeout <= 0) {
+		printk(BIOS_ERR, "I2C Start::Send Start Bit Timeout\n");
+		res = I2C_TIMEOUT;
+	}
+
+	return res;
+}
+
+static int i2c_send_stop(struct rk3288_i2c_regs *reg_addr)
+{
+	int res = 0;
+	int timeout = I2C_TIMEOUT_US;
+
+	i2c_info("I2c Stop::Send Stop bit\n");
+	writel(I2C_CLEANI, &reg_addr->i2c_ipd);
+	writel(I2C_EN | I2C_STOP, &reg_addr->i2c_con);
+	while (timeout--) {
+		if (readl(&reg_addr->i2c_ipd) & I2C_STOPI)
+			break;
+		udelay(1);
+	}
+	writel(0, &reg_addr->i2c_con);
+	if (timeout <= 0) {
+		printk(BIOS_ERR, "I2C Stop::Send Stop Bit Timeout\n");
+		res = I2C_TIMEOUT;
+	}
+
+	return res;
+}
+
+static int i2c_read(struct rk3288_i2c_regs *reg_addr, struct i2c_seg segment)
+{
+	int res = 0;
+	uint8_t *data = segment.buf;
+	int timeout = I2C_TIMEOUT_US;
+	unsigned int bytes_remaining = segment.len;
+	unsigned int bytes_transfered = 0;
+	unsigned int words_transfered = 0;
+	unsigned int rxdata = 0;
+	unsigned int con = 0;
+	unsigned int i, j;
+
+	writel(I2C_8BIT | segment.chip << 1 | 1, &reg_addr->i2c_mrxaddr);
+	writel(0, &reg_addr->i2c_mrxraddr);
+	con = I2C_MODE_TRX | I2C_EN;
+	while (bytes_remaining) {
+		bytes_transfered = MIN(bytes_remaining, 32);
+		bytes_remaining -= bytes_transfered;
+		if (!bytes_remaining)
+			con |= I2C_EN | I2C_NAK;
+		words_transfered = ALIGN_UP(bytes_transfered, 4) / 4;
+
+		writel(I2C_CLEANI, &reg_addr->i2c_ipd);
+		writel(con, &reg_addr->i2c_con);
+		writel(bytes_transfered, &reg_addr->i2c_mrxcnt);
+
+		timeout = I2C_TIMEOUT_US;
+		while (timeout--) {
+			if (readl(&reg_addr->i2c_ipd) & I2C_NAKRCVI) {
+				writel(0, &reg_addr->i2c_mrxcnt);
+				writel(0, &reg_addr->i2c_con);
+				return I2C_NOACK;
+			}
+			if (readl(&reg_addr->i2c_ipd) & I2C_MBRFI)
+				break;
+			udelay(1);
+		}
+		if (timeout <= 0) {
+			printk(BIOS_ERR, "I2C Read::Recv Data Timeout\n");
+			writel(0, &reg_addr->i2c_mrxcnt);
+			writel(0, &reg_addr->i2c_con);
+			return	I2C_TIMEOUT;
+		}
+
+		for (i = 0; i < words_transfered; i++) {
+			rxdata = readl(&reg_addr->rxdata[i]);
+			i2c_info("I2c Read::RXDATA[%d] = 0x%x\n", i, rxdata);
+			for (j = 0; j < 4; j++) {
+				if ((i * 4 + j) == bytes_transfered)
+					break;
+				*data++ = (rxdata >> (j * 8)) & 0xff;
+			}
+		}
+		con = I2C_MODE_RX | I2C_EN;
+	}
+	return res;
+}
+
+static int i2c_write(struct rk3288_i2c_regs *reg_addr, struct i2c_seg segment)
+{
+	int res = 0;
+	uint8_t *data = segment.buf;
+	int timeout = I2C_TIMEOUT_US;
+	int bytes_remaining = segment.len + 1;
+	int bytes_transfered = 0;
+	int words_transfered = 0;
+	unsigned int i;
+	unsigned int j = 1;
+	u32 txdata = 0;
+
+	txdata |= (segment.chip << 1);
+	while (bytes_remaining) {
+		bytes_transfered = MIN(bytes_remaining, 32);
+		words_transfered = ALIGN_UP(bytes_transfered, 4) / 4;
+		for (i = 0; i < words_transfered; i++) {
+			do {
+				if ((i * 4 + j) == bytes_transfered)
+					break;
+				txdata |= (*data++) << (j * 8);
+			} while (++j < 4);
+			writel(txdata, &reg_addr->txdata[i]);
+			j = 0;
+			i2c_info("I2c Write::TXDATA[%d] = 0x%x\n", i, txdata);
+			txdata = 0;
+		}
+
+		writel(I2C_CLEANI, &reg_addr->i2c_ipd);
+		writel(I2C_EN | I2C_MODE_TX, &reg_addr->i2c_con);
+		writel(bytes_transfered, &reg_addr->i2c_mtxcnt);
+
+		timeout = I2C_TIMEOUT_US;
+		while (timeout--) {
+			if (readl(&reg_addr->i2c_ipd) & I2C_NAKRCVI) {
+				writel(0, &reg_addr->i2c_mtxcnt);
+				writel(0, &reg_addr->i2c_con);
+				return I2C_NOACK;
+			}
+			if (readl(&reg_addr->i2c_ipd) & I2C_MBTFI)
+				break;
+			udelay(1);
+		}
+
+		if (timeout <= 0) {
+			printk(BIOS_ERR, "I2C Write::Send Data Timeout\n");
+			writel(0, &reg_addr->i2c_mtxcnt);
+			writel(0, &reg_addr->i2c_con);
+			return	I2C_TIMEOUT;
+		}
+
+		bytes_remaining -= bytes_transfered;
+	}
+	return res;
+}
+
+static int i2c_do_xfer(void *reg_addr, struct i2c_seg segment)
+{
+	int res = 0;
+
+	if (i2c_send_start(reg_addr))
+		return I2C_TIMEOUT;
+	if (segment.read)
+		res = i2c_read(reg_addr, segment);
+	else
+		res = i2c_write(reg_addr, segment);
+	return i2c_send_stop(reg_addr) || res;
+}
+
+int platform_i2c_transfer(unsigned bus, struct i2c_seg *segments, int seg_count)
+{
+	int i;
+	int res = 0;
+	struct rk3288_i2c_regs *regs = i2c_bus[bus];
+	struct i2c_seg  *seg = segments;
+
+	for (i = 0; i < seg_count; i++, seg++) {
+		res = i2c_do_xfer(regs, *seg);
+		if (res)
+			break;
+	}
+	return res;
+}