[RFC 3/8] powerpc: Add bootwrapper support for Marvell/mv64x60 I2C

Mark A. Greer mgreer at mvista.com
Wed Mar 28 11:10:19 EST 2007


Signed-off-by: Mark A. Greer <mgreer at mvista.com>
---

 Makefile      |    3 
 mv64x60_i2c.c |  206 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 208 insertions(+), 1 deletion(-)
---

diff --git a/arch/powerpc/boot/mv64x60_i2c.c b/arch/powerpc/boot/mv64x60_i2c.c
Index: powerpc/arch/powerpc/boot/mv64x60_i2c.c
===================================================================
--- /dev/null
+++ powerpc/arch/powerpc/boot/mv64x60_i2c.c
@@ -0,0 +1,206 @@
+/*
+ * Bootloader version of the i2c driver for the MV64x60.
+ *
+ * Author: Dale Farnsworth <dfarnsworth at mvista.com>
+ * Maintained by: Mark A. Greer <mgreer at mvista.com>
+ *
+ * 2003, 2007 (c) MontaVista, Software, Inc.  This file is licensed under
+ * the terms of the GNU General Public License version 2.  This program is
+ * licensed "as is" without any warranty of any kind, whether express or
+ * implied.
+ */
+
+#include <stdarg.h>
+#include <stddef.h>
+#include "types.h"
+#include "elf.h"
+#include "page.h"
+#include "string.h"
+#include "stdio.h"
+#include "io.h"
+#include "ops.h"
+#include "mv64x60.h"
+
+extern void udelay(long);
+
+/* Register defines */
+#define	MV64x60_I2C_REG_SLAVE_ADDR			0x00
+#define	MV64x60_I2C_REG_DATA				0x04
+#define	MV64x60_I2C_REG_CONTROL				0x08
+#define	MV64x60_I2C_REG_STATUS				0x0c
+#define	MV64x60_I2C_REG_BAUD				0x0c
+#define	MV64x60_I2C_REG_EXT_SLAVE_ADDR			0x10
+#define	MV64x60_I2C_REG_SOFT_RESET			0x1c
+
+#define	MV64x60_I2C_CONTROL_ACK				0x04
+#define	MV64x60_I2C_CONTROL_IFLG			0x08
+#define	MV64x60_I2C_CONTROL_STOP			0x10
+#define	MV64x60_I2C_CONTROL_START			0x20
+#define	MV64x60_I2C_CONTROL_TWSIEN			0x40
+#define	MV64x60_I2C_CONTROL_INTEN			0x80
+
+#define	MV64x60_I2C_STATUS_BUS_ERR			0x00
+#define	MV64x60_I2C_STATUS_MAST_START			0x08
+#define	MV64x60_I2C_STATUS_MAST_REPEAT_START		0x10
+#define	MV64x60_I2C_STATUS_MAST_WR_ADDR_ACK		0x18
+#define	MV64x60_I2C_STATUS_MAST_WR_ADDR_NO_ACK		0x20
+#define	MV64x60_I2C_STATUS_MAST_WR_ACK			0x28
+#define	MV64x60_I2C_STATUS_MAST_WR_NO_ACK		0x30
+#define	MV64x60_I2C_STATUS_MAST_LOST_ARB		0x38
+#define	MV64x60_I2C_STATUS_MAST_RD_ADDR_ACK		0x40
+#define	MV64x60_I2C_STATUS_MAST_RD_ADDR_NO_ACK		0x48
+#define	MV64x60_I2C_STATUS_MAST_RD_DATA_ACK		0x50
+#define	MV64x60_I2C_STATUS_MAST_RD_DATA_NO_ACK		0x58
+#define	MV64x60_I2C_STATUS_MAST_WR_ADDR_2_ACK		0xd0
+#define	MV64x60_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK	0xd8
+#define	MV64x60_I2C_STATUS_MAST_RD_ADDR_2_ACK		0xe0
+#define	MV64x60_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK	0xe8
+#define	MV64x60_I2C_STATUS_NO_STATUS			0xf8
+
+static u8 *ctlr_base;
+
+static int mv64x60_i2c_wait_for_status(int wanted)
+{
+	int i;
+	int status;
+
+	for (i=0; i<1000; i++) {
+		udelay(10);
+		status = in_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_STATUS))
+			& 0xff;
+		if (status == wanted)
+			return status;
+	}
+	return -status;
+}
+
+static int mv64x60_i2c_control(int control, int status)
+{
+	out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
+	return mv64x60_i2c_wait_for_status(status);
+}
+
+static int mv64x60_i2c_read_byte(int control, int status)
+{
+	out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
+	if (mv64x60_i2c_wait_for_status(status) < 0)
+		return -1;
+	return in_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_DATA)) & 0xff;
+}
+
+static int mv64x60_i2c_write_byte(int data, int control, int status)
+{
+	out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_DATA), data & 0xff);
+	out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
+	return mv64x60_i2c_wait_for_status(status);
+}
+
+int mv64x60_i2c_read(u32 devaddr, u8 *buf, u32 offset, u32 offset_size,
+		 u32 count)
+{
+	int i;
+	int data;
+	int control;
+	int status;
+
+	if (ctlr_base == NULL)
+		return -1;
+
+	/* send reset */
+	out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_SOFT_RESET), 0);
+	out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_SLAVE_ADDR), 0);
+	out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_EXT_SLAVE_ADDR), 0);
+	out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_BAUD), (4 << 3) | 0x4);
+
+	if (mv64x60_i2c_control(MV64x60_I2C_CONTROL_TWSIEN,
+				MV64x60_I2C_STATUS_NO_STATUS) < 0)
+		return -1;
+
+	/* send start */
+	control = MV64x60_I2C_CONTROL_START | MV64x60_I2C_CONTROL_TWSIEN;
+	status = MV64x60_I2C_STATUS_MAST_START;
+	if (mv64x60_i2c_control(control, status) < 0)
+		return -1;
+
+	/* select device for writing */
+	data = devaddr & ~0x1;
+	control = MV64x60_I2C_CONTROL_TWSIEN;
+	status = MV64x60_I2C_STATUS_MAST_WR_ADDR_ACK;
+	if (mv64x60_i2c_write_byte(data, control, status) < 0)
+		return -1;
+
+	/* send offset of data */
+	control = MV64x60_I2C_CONTROL_TWSIEN;
+	status = MV64x60_I2C_STATUS_MAST_WR_ACK;
+	if (offset_size > 1) {
+		if (mv64x60_i2c_write_byte(offset >> 8, control, status) < 0)
+			return -1;
+	}
+	if (mv64x60_i2c_write_byte(offset, control, status) < 0)
+		return -1;
+
+	/* resend start */
+	control = MV64x60_I2C_CONTROL_START | MV64x60_I2C_CONTROL_TWSIEN;
+	status = MV64x60_I2C_STATUS_MAST_REPEAT_START;
+	if (mv64x60_i2c_control(control, status) < 0)
+		return -1;
+
+	/* select device for reading */
+	data = devaddr | 0x1;
+	control = MV64x60_I2C_CONTROL_TWSIEN;
+	status = MV64x60_I2C_STATUS_MAST_RD_ADDR_ACK;
+	if (mv64x60_i2c_write_byte(data, control, status) < 0)
+		return -1;
+
+	/* read all but last byte of data */
+	control = MV64x60_I2C_CONTROL_ACK | MV64x60_I2C_CONTROL_TWSIEN;
+	status = MV64x60_I2C_STATUS_MAST_RD_DATA_ACK;
+
+	for (i=1; i<count; i++) {
+		data = mv64x60_i2c_read_byte(control, status);
+		if (data < 0) {
+			printf("errors on iteration %d\n", i);
+			return -1;
+		}
+		*buf++ = data;
+	}
+
+	/* read last byte of data */
+	control = MV64x60_I2C_CONTROL_TWSIEN;
+	status = MV64x60_I2C_STATUS_MAST_RD_DATA_NO_ACK;
+	data = mv64x60_i2c_read_byte(control, status);
+	if (data < 0)
+		return -1;
+	*buf++ = data;
+
+	/* send stop */
+	control = MV64x60_I2C_CONTROL_STOP | MV64x60_I2C_CONTROL_TWSIEN;
+	status = MV64x60_I2C_STATUS_NO_STATUS;
+	if (mv64x60_i2c_control(control, status) < 0)
+		return -1;
+
+	return count;
+}
+
+int mv64x60_i2c_open(void)
+{
+	u32 v;
+	void *devp;
+
+	devp = finddevice("/mv64x60/i2c");
+	if (devp == NULL)
+		goto err_out;
+	if (getprop(devp, "virtual-reg", &v, sizeof(v)) != sizeof(v))
+		goto err_out;
+
+	ctlr_base = (u8 *)v;
+	return 0;
+
+err_out:
+	return -1;
+}
+
+void mv64x60_i2c_close(void)
+{
+	ctlr_base = NULL;
+}
Index: powerpc/arch/powerpc/boot/Makefile
===================================================================
--- powerpc.orig/arch/powerpc/boot/Makefile
+++ powerpc/arch/powerpc/boot/Makefile
@@ -42,7 +42,8 @@ $(addprefix $(obj)/,$(zlib) main.o): $(a
 
 src-wlib := string.S crt0.S stdio.c main.c flatdevtree.c flatdevtree_misc.c \
 		ns16550.c serial.c simple_alloc.c div64.S util.S \
-		gunzip_util.c devtree.c elf_util.c mv64x60.c mpsc.c $(zlib)
+		gunzip_util.c devtree.c elf_util.c mv64x60.c mpsc.c \
+		mv64x60_i2c.c $(zlib)
 cuboot-plats := 83xx
 src-plat := of.c $(cuboot-plats:%=cuboot-%.c)
 src-boot := $(src-wlib) $(src-plat) empty.c



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