From b24f119d672b709d153ff2ac091d4aa63ec6877d Mon Sep 17 00:00:00 2001
From: Ben Warren <bwarren@qstreams.com>
Date: Thu, 7 Sep 2006 16:51:04 -0400
Subject: [PATCH] Multi-bus I2C implementation of MPC834x
Hello,
Attached is a patch implementing multiple I2C buses on the MPC834x CPU
family and the MPC8349EMDS board in particular.
This patch requires Patch 1 (Add support for multiple I2C buses).
Testing was performed on a 533MHz board.
/*** Note: This patch replaces ticket DNX#2006083042000027 ***/
Signed-off-by: Ben Warren <bwarren@qstreams.com>
CHANGELOG:
Implemented driver-level code to support two I2C buses on the
MPC834x CPU family and the MPC8349EMDS board. Available I2C bus speeds
are 50kHz, 100kHz and 400kHz on each bus.
regards,
Ben
---
cpu/mpc83xx/i2c.c | 168 ++++++++++++++++++++++++++++++++++++------
include/asm-ppc/i2c.h | 21 +++---
include/configs/MPC8349EMDS.h | 6 +-
3 files changed, 160 insertions(+), 35 deletions(-)
diff --git a/cpu/mpc83xx/i2c.c b/cpu/mpc83xx/i2c.c
index 723feeb..fc89fb1 100644
--- a/cpu/mpc83xx/i2c.c
+++ b/cpu/mpc83xx/i2c.c
@@ -45,37 +45,123 @@
#include <i2c.h>
#include <asm/i2c.h>
-#if defined(CONFIG_MPC8349EMDS) || defined(CONFIG_TQM834X)
-i2c_t * mpc83xx_i2c = (i2c_t*)(CFG_IMMRBAR + CFG_I2C_OFFSET);
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Three I2C bus speeds are supported here (50kHz, 100kHz
+ * and 400kHz). It should be easy to add more. Note that
+ * the maximum bus speed for I2C bus 1 is CSB/3, while I2C
+ * bus 2 can go as high as CSB.
+ * Typical values for CSB are 266MHz and 200MHz. */
+
+ /* 50kH 100kHz 400kHz */
+static const uchar speed_map_266[][3] =
+ {{0x2e, 0x2a, 0x20}, /* base 88MHz */
+ {0x34, 0x30, 0x28}}; /* base 266 MHz */
+
+static const uchar speed_map_200[][3] =
+ {{0x2c, 0x28, 0x20}, /* base 66 MHz */
+ {0x33, 0x2f, 0x26}}; /* base 200 MHz */
+
+/* Initialize the bus pointer to whatever one the SPD EEPROM is on.
+ * Default is bus 1. This is necessary because the DDR initialization
+ * runs from ROM, and we can't switch buses because we can't modify
+ * the i2c_dev variable. Everything gets straightened out once i2c_init
+ * is called from RAM. */
+
+#if defined CFG_SPD_BUS_NUM
+static i2c_t *i2c_dev = CFG_SPD_BUS_NUM;
+#else
+static i2c_t *i2c_dev = I2C_1;
#endif
-void
-i2c_init(int speed, int slaveadd)
+static uchar busNum = I2C_BUS_1 ;
+static int bus_speed[2] = {0, 0};
+
+static int set_speed(int speed)
+{
+ uchar value;
+ const uchar *spdPtr;
+
+ /* Global data contains maximum I2C bus 1 speed, which is CSB/3 */
+ if(gd->i2c_clk == 88000000)
+ {
+ spdPtr = speed_map_266[busNum];
+ }
+ else if(gd->i2c_clk == 66000000)
+ {
+ spdPtr = speed_map_200[busNum];
+ }
+ else
+ {
+ printf("Max I2C bus speed %d not supported\n", gd->i2c_clk);
+ return -1;
+ }
+
+ switch(speed)
+ {
+ case 50000:
+ value = *(spdPtr + 0);
+ break;
+ case 100000:
+ value = *(spdPtr + 1);
+ break;
+ case 400000:
+ value = *(spdPtr + 2);
+ break;
+ default:
+ printf("I2C bus speed %d not supported\n", speed);
+ return -2;
+ }
+ /* set clock */
+ writeb(value, &i2c_dev->fdr);
+ bus_speed[busNum] = speed;
+ return 0;
+}
+
+
+static void _i2c_init(int speed, int slaveadd)
{
/* stop I2C controller */
- writeb(0x00 , &I2C->cr);
+ writeb(0x00 , &i2c_dev->cr);
/* set clock */
- writeb(speed, &I2C->fdr);
+ writeb(speed, &i2c_dev->fdr);
/* set default filter */
- writeb(0x10,&I2C->dfsrr);
+ writeb(0x10,&i2c_dev->dfsrr);
/* write slave address */
- writeb(slaveadd, &I2C->adr);
+ writeb(slaveadd, &i2c_dev->adr);
/* clear status register */
- writeb(0x00, &I2C->sr);
+ writeb(0x00, &i2c_dev->sr);
/* start I2C controller */
- writeb(I2C_CR_MEN, &I2C->cr);
+ writeb(I2C_CR_MEN, &i2c_dev->cr);
+}
+
+void i2c_init(int speed, int slaveadd)
+{
+ /* Set both interfaces to the same speed and slave address */
+ /* Note: This function gets called twice - before and after
+ * relocation to RAM. The first time it's called, we are unable
+ * to change buses, so whichever one 'i2c_dev' was initialized to
+ * gets set twice. When run from RAM both buses get set properly */
+
+ i2c_set_bus_num(I2C_BUS_1);
+ _i2c_init(speed, slaveadd);
+#ifdef CFG_I2C2_OFFSET
+ i2c_set_bus_num(I2C_BUS_2);
+ _i2c_init(speed, slaveadd);
+ i2c_set_bus_num(I2C_BUS_1);
+#endif /* CFG_I2C2_OFFSET */
}
static __inline__ int
i2c_wait4bus (void)
{
ulong timeval = get_timer (0);
- while (readb(&I2C->sr) & I2C_SR_MBB) {
+ while (readb(&i2c_dev->sr) & I2C_SR_MBB) {
if (get_timer (timeval) > I2C_TIMEOUT) {
return -1;
}
@@ -89,12 +175,12 @@ i2c_wait (int write)
u32 csr;
ulong timeval = get_timer(0);
do {
- csr = readb(&I2C->sr);
+ csr = readb(&i2c_dev->sr);
if (!(csr & I2C_SR_MIF))
continue;
- writeb(0x0, &I2C->sr);
+ writeb(0x0, &i2c_dev->sr);
if (csr & I2C_SR_MAL) {
debug("i2c_wait: MAL\n");
@@ -123,9 +209,9 @@ i2c_write_addr (u8 dev, u8 dir, int rsta)
{
writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX |
(rsta?I2C_CR_RSTA:0),
- &I2C->cr);
+ &i2c_dev->cr);
- writeb((dev << 1) | dir, &I2C->dr);
+ writeb((dev << 1) | dir, &i2c_dev->dr);
if (i2c_wait (I2C_WRITE) < 0)
return 0;
@@ -138,10 +224,10 @@ __i2c_write (u8 *data, int length)
int i;
writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX,
- &I2C->cr);
+ &i2c_dev->cr);
for (i=0; i < length; i++) {
- writeb(data[i], &I2C->dr);
+ writeb(data[i], &i2c_dev->dr);
if (i2c_wait (I2C_WRITE) < 0)
break;
@@ -156,10 +242,10 @@ __i2c_read (u8 *data, int length)
writeb(I2C_CR_MEN | I2C_CR_MSTA |
((length == 1) ? I2C_CR_TXAK : 0),
- &I2C->cr);
+ &i2c_dev->cr);
/* dummy read */
- readb(&I2C->dr);
+ readb(&i2c_dev->dr);
for (i=0; i < length; i++) {
if (i2c_wait (I2C_READ) < 0)
@@ -169,13 +255,13 @@ __i2c_read (u8 *data, int length)
if (i == length - 2)
writeb(I2C_CR_MEN | I2C_CR_MSTA |
I2C_CR_TXAK,
- &I2C->cr);
+ &i2c_dev->cr);
/* Generate stop on last byte */
if (i == length - 1)
- writeb(I2C_CR_MEN | I2C_CR_TXAK, &I2C->cr);
+ writeb(I2C_CR_MEN | I2C_CR_TXAK, &i2c_dev->cr);
- data[i] = readb(&I2C->dr);
+ data[i] = readb(&i2c_dev->dr);
}
return i;
}
@@ -201,7 +287,7 @@ i2c_read (u8 dev, uint addr, int alen, u8 *data, int length)
i = __i2c_read (data, length);
exit:
- writeb(I2C_CR_MEN, &I2C->cr);
+ writeb(I2C_CR_MEN, &i2c_dev->cr);
return !(i == length);
}
@@ -223,7 +309,7 @@ i2c_write (u8 dev, uint addr, int alen, u8 *data, int length)
i = __i2c_write (data, length);
exit:
- writeb(I2C_CR_MEN, &I2C->cr);
+ writeb(I2C_CR_MEN, &i2c_dev->cr);
return !(i == length);
}
@@ -254,4 +340,38 @@ void i2c_reg_write (uchar i2c_addr, uchar reg, uchar val)
i2c_write (i2c_addr, reg, 1, &val, 1);
}
+int i2c_set_bus_num(uchar bus)
+{
+ if(bus == I2C_BUS_1)
+ {
+ i2c_dev = I2C_1;
+ }
+#ifdef CFG_I2C2_OFFSET
+ else if(bus == I2C_BUS_2)
+ {
+ i2c_dev = I2C_2;
+ }
+#endif /* CFG_I2C2_OFFSET */
+ else
+ {
+ return -1;
+ }
+ busNum = bus;
+ return 0;
+}
+
+int i2c_set_bus_speed(int speed)
+{
+ return set_speed(speed);
+}
+
+uchar i2c_get_bus_num(void)
+{
+ return busNum;
+}
+
+int i2c_get_bus_speed(void)
+{
+ return bus_speed[busNum];
+}
#endif /* CONFIG_HARD_I2C */
diff --git a/include/asm-ppc/i2c.h b/include/asm-ppc/i2c.h
index 2ae3367..baf9d9a 100644
--- a/include/asm-ppc/i2c.h
+++ b/include/asm-ppc/i2c.h
@@ -79,6 +79,12 @@ typedef struct i2c
#endif
#define I2C_TIMEOUT (CFG_HZ/4)
+enum I2C_BUS_NUM
+{
+ I2C_BUS_1 = 0,
+ I2C_BUS_2,
+};
+
#ifndef CFG_IMMRBAR
#error CFG_IMMRBAR is not defined in /include/configs/${BOARD}.h
#endif
@@ -87,15 +93,12 @@ typedef struct i2c
#error CFG_I2C_OFFSET is not defined in /include/configs/${BOARD}.h
#endif
-#if defined(CONFIG_MPC8349EMDS) || defined(CONFIG_TQM834X)
-/*
- * MPC8349 have two i2c bus
- */
-extern i2c_t * mpc83xx_i2c;
-#define I2C mpc83xx_i2c
-#else
-#define I2C ((i2c_t*)(CFG_IMMRBAR + CFG_I2C_OFFSET))
-#endif
+#define I2C_1 ((i2c_t*)(CFG_IMMRBAR + CFG_I2C_OFFSET))
+
+/* Optional support for second I2C bus */
+#ifdef CFG_I2C2_OFFSET
+#define I2C_2 ((i2c_t*)(CFG_IMMRBAR + CFG_I2C2_OFFSET))
+#endif /* CFG_I2C2_OFFSET */
#define I2C_READ 1
#define I2C_WRITE 0
diff --git a/include/configs/MPC8349EMDS.h b/include/configs/MPC8349EMDS.h
index 66f1646..4d5ad57 100644
--- a/include/configs/MPC8349EMDS.h
+++ b/include/configs/MPC8349EMDS.h
@@ -35,7 +35,7 @@
* High Level Configuration Options
*/
#define CONFIG_E300 1 /* E300 Family */
-#define CONFIG_MPC83XX 1 /* MPC83XX family */
+#define CONFIG_MPC834X 1 /* MPC834X family */
#define CONFIG_MPC8349 1 /* MPC8349 specific */
#define CONFIG_MPC8349EMDS 1 /* MPC8349EMDS board specific */
@@ -311,9 +311,11 @@
/* I2C */
#define CONFIG_HARD_I2C /* I2C with hardware support*/
#undef CONFIG_SOFT_I2C /* I2C bit-banged */
+#define CONFIG_I2C_MULTI_BUS
+#define CONFIG_I2C_CMD_TREE
#define CFG_I2C_SPEED 400000 /* I2C speed and slave address */
#define CFG_I2C_SLAVE 0x7F
-#define CFG_I2C_NOPROBES {0x69} /* Don't probe these addrs */
+#define CFG_I2C_NOPROBES {{0,0x69}} /* Don't probe these addrs */
#define CFG_I2C_OFFSET 0x3000
#define CFG_I2C2_OFFSET 0x3100