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authorScott Wood <scottwood@freescale.com>2012-12-14 16:03:55 -0600
committerScott Wood <scottwood@freescale.com>2012-12-14 16:03:55 -0600
commit88c5c68ffa277bf01b3254cf5a059e2cbe07be97 (patch)
treef56b444a1c85d94d6a386df090def099632489fe /drivers
parent0b38fffbe413fc0725c750d046ca62c23fca196e (diff)
parent6e9005bd96ff0f0548a787ffafee10664a57a8e1 (diff)
Merge remote-tracking branch 'origin/master'
Diffstat (limited to 'drivers')
-rw-r--r--drivers/i2c/designware_i2c.c121
-rw-r--r--drivers/i2c/designware_i2c.h9
-rw-r--r--drivers/i2c/mxc_i2c.c4
-rw-r--r--drivers/i2c/mxs_i2c.c82
-rw-r--r--drivers/i2c/omap24xx_i2c.c15
-rw-r--r--drivers/i2c/s3c24x0_i2c.c19
-rw-r--r--drivers/i2c/soft_i2c.c3
-rw-r--r--drivers/serial/serial.c70
8 files changed, 262 insertions, 61 deletions
diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c
index bf64a2a64..665387091 100644
--- a/drivers/i2c/designware_i2c.c
+++ b/drivers/i2c/designware_i2c.c
@@ -26,7 +26,12 @@
#include <asm/arch/hardware.h>
#include "designware_i2c.h"
-static struct i2c_regs *const i2c_regs_p =
+#ifdef CONFIG_I2C_MULTI_BUS
+static unsigned int bus_initialized[CONFIG_SYS_I2C_BUS_MAX];
+static unsigned int current_bus = 0;
+#endif
+
+static struct i2c_regs *i2c_regs_p =
(struct i2c_regs *)CONFIG_SYS_I2C_BASE;
/*
@@ -39,7 +44,6 @@ static void set_speed(int i2c_spd)
{
unsigned int cntl;
unsigned int hcnt, lcnt;
- unsigned int high, low;
unsigned int enbl;
/* to set speed cltr must be disabled */
@@ -47,39 +51,38 @@ static void set_speed(int i2c_spd)
enbl &= ~IC_ENABLE_0B;
writel(enbl, &i2c_regs_p->ic_enable);
-
cntl = (readl(&i2c_regs_p->ic_con) & (~IC_CON_SPD_MSK));
switch (i2c_spd) {
case IC_SPEED_MODE_MAX:
cntl |= IC_CON_SPD_HS;
- high = MIN_HS_SCL_HIGHTIME;
- low = MIN_HS_SCL_LOWTIME;
+ hcnt = (IC_CLK * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO;
+ writel(hcnt, &i2c_regs_p->ic_hs_scl_hcnt);
+ lcnt = (IC_CLK * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO;
+ writel(lcnt, &i2c_regs_p->ic_hs_scl_lcnt);
break;
case IC_SPEED_MODE_STANDARD:
cntl |= IC_CON_SPD_SS;
- high = MIN_SS_SCL_HIGHTIME;
- low = MIN_SS_SCL_LOWTIME;
+ hcnt = (IC_CLK * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO;
+ writel(hcnt, &i2c_regs_p->ic_ss_scl_hcnt);
+ lcnt = (IC_CLK * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO;
+ writel(lcnt, &i2c_regs_p->ic_ss_scl_lcnt);
break;
case IC_SPEED_MODE_FAST:
default:
cntl |= IC_CON_SPD_FS;
- high = MIN_FS_SCL_HIGHTIME;
- low = MIN_FS_SCL_LOWTIME;
+ hcnt = (IC_CLK * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO;
+ writel(hcnt, &i2c_regs_p->ic_fs_scl_hcnt);
+ lcnt = (IC_CLK * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO;
+ writel(lcnt, &i2c_regs_p->ic_fs_scl_lcnt);
break;
}
writel(cntl, &i2c_regs_p->ic_con);
- hcnt = (IC_CLK * high) / NANO_TO_MICRO;
- writel(hcnt, &i2c_regs_p->ic_fs_scl_hcnt);
-
- lcnt = (IC_CLK * low) / NANO_TO_MICRO;
- writel(lcnt, &i2c_regs_p->ic_fs_scl_lcnt);
-
- /* re-enable i2c ctrl back now that speed is set */
+ /* Enable back i2c now speed set */
enbl |= IC_ENABLE_0B;
writel(enbl, &i2c_regs_p->ic_enable);
}
@@ -150,6 +153,10 @@ void i2c_init(int speed, int slaveadd)
enbl = readl(&i2c_regs_p->ic_enable);
enbl |= IC_ENABLE_0B;
writel(enbl, &i2c_regs_p->ic_enable);
+
+#ifdef CONFIG_I2C_MULTI_BUS
+ bus_initialized[current_bus] = 1;
+#endif
}
/*
@@ -274,7 +281,10 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
start_time_rx = get_timer(0);
while (len) {
- writel(IC_CMD, &i2c_regs_p->ic_cmd_data);
+ if (len == 1)
+ writel(IC_CMD | IC_STOP, &i2c_regs_p->ic_cmd_data);
+ else
+ writel(IC_CMD, &i2c_regs_p->ic_cmd_data);
if (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE) {
*buffer++ = (uchar)readl(&i2c_regs_p->ic_cmd_data);
@@ -313,9 +323,11 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
start_time_tx = get_timer(0);
while (len) {
if (readl(&i2c_regs_p->ic_status) & IC_STATUS_TFNF) {
- writel(*buffer, &i2c_regs_p->ic_cmd_data);
+ if (--len == 0)
+ writel(*buffer | IC_STOP, &i2c_regs_p->ic_cmd_data);
+ else
+ writel(*buffer, &i2c_regs_p->ic_cmd_data);
buffer++;
- len--;
start_time_tx = get_timer(0);
} else if (get_timer(start_time_tx) > (nb * I2C_BYTE_TO)) {
@@ -344,3 +356,74 @@ int i2c_probe(uchar chip)
return ret;
}
+
+#ifdef CONFIG_I2C_MULTI_BUS
+int i2c_set_bus_num(unsigned int bus)
+{
+ switch (bus) {
+ case 0:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE;
+ break;
+#ifdef CONFIG_SYS_I2C_BASE1
+ case 1:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE1;
+ break;
+#endif
+#ifdef CONFIG_SYS_I2C_BASE2
+ case 2:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE2;
+ break;
+#endif
+#ifdef CONFIG_SYS_I2C_BASE3
+ case 3:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE3;
+ break;
+#endif
+#ifdef CONFIG_SYS_I2C_BASE4
+ case 4:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE4;
+ break;
+#endif
+#ifdef CONFIG_SYS_I2C_BASE5
+ case 5:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE5;
+ break;
+#endif
+#ifdef CONFIG_SYS_I2C_BASE6
+ case 6:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE6;
+ break;
+#endif
+#ifdef CONFIG_SYS_I2C_BASE7
+ case 7:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE7;
+ break;
+#endif
+#ifdef CONFIG_SYS_I2C_BASE8
+ case 8:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE8;
+ break;
+#endif
+#ifdef CONFIG_SYS_I2C_BASE9
+ case 9:
+ i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE9;
+ break;
+#endif
+ default:
+ printf("Bad bus: %d\n", bus);
+ return -1;
+ }
+
+ current_bus = bus;
+
+ if (!bus_initialized[current_bus])
+ i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+
+ return 0;
+}
+
+int i2c_get_bus_num(void)
+{
+ return current_bus;
+}
+#endif
diff --git a/drivers/i2c/designware_i2c.h b/drivers/i2c/designware_i2c.h
index 03b520ed4..2faf4a871 100644
--- a/drivers/i2c/designware_i2c.h
+++ b/drivers/i2c/designware_i2c.h
@@ -60,14 +60,16 @@ struct i2c_regs {
u32 ic_tx_abrt_source;
};
+#if !defined(IC_CLK)
#define IC_CLK 166
+#endif
#define NANO_TO_MICRO 1000
/* High and low times in different speed modes (in ns) */
#define MIN_SS_SCL_HIGHTIME 4000
-#define MIN_SS_SCL_LOWTIME 5000
-#define MIN_FS_SCL_HIGHTIME 800
-#define MIN_FS_SCL_LOWTIME 1700
+#define MIN_SS_SCL_LOWTIME 4700
+#define MIN_FS_SCL_HIGHTIME 600
+#define MIN_FS_SCL_LOWTIME 1300
#define MIN_HS_SCL_HIGHTIME 60
#define MIN_HS_SCL_LOWTIME 160
@@ -95,6 +97,7 @@ struct i2c_regs {
/* i2c data buffer and command register definitions */
#define IC_CMD 0x0100
+#define IC_STOP 0x0200
/* i2c interrupt status register definitions */
#define IC_GEN_CALL 0x0800
diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
index 18270b9de..a73b10b9c 100644
--- a/drivers/i2c/mxc_i2c.c
+++ b/drivers/i2c/mxc_i2c.c
@@ -115,7 +115,7 @@ static uint8_t i2c_imx_get_clk(unsigned int rate)
/*
* Set I2C Bus speed
*/
-int bus_i2c_set_bus_speed(void *base, int speed)
+static int bus_i2c_set_bus_speed(void *base, int speed)
{
struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
u8 clk_idx = i2c_imx_get_clk(speed);
@@ -133,7 +133,7 @@ int bus_i2c_set_bus_speed(void *base, int speed)
/*
* Get I2C Speed
*/
-unsigned int bus_i2c_get_bus_speed(void *base)
+static unsigned int bus_i2c_get_bus_speed(void *base)
{
struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
u8 clk_idx = readb(&i2c_regs->ifdr);
diff --git a/drivers/i2c/mxs_i2c.c b/drivers/i2c/mxs_i2c.c
index 2a193c220..b907f7b37 100644
--- a/drivers/i2c/mxs_i2c.c
+++ b/drivers/i2c/mxs_i2c.c
@@ -28,6 +28,7 @@
#include <common.h>
#include <malloc.h>
+#include <i2c.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
@@ -40,6 +41,7 @@ void mxs_i2c_reset(void)
{
struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
int ret;
+ int speed = i2c_get_bus_speed();
ret = mxs_reset_block(&i2c_regs->hw_i2c_ctrl0_reg);
if (ret) {
@@ -53,6 +55,8 @@ void mxs_i2c_reset(void)
&i2c_regs->hw_i2c_ctrl1_clr);
writel(I2C_QUEUECTRL_PIO_QUEUE_MODE, &i2c_regs->hw_i2c_queuectrl_set);
+
+ i2c_set_bus_speed(speed);
}
void mxs_i2c_setup_read(uint8_t chip, int len)
@@ -210,37 +214,65 @@ int i2c_probe(uchar chip)
return ret;
}
-void i2c_init(int speed, int slaveadd)
+int i2c_set_bus_speed(unsigned int speed)
{
struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
+ /*
+ * The timing derivation algorithm. There is no documentation for this
+ * algorithm available, it was derived by using the scope and fiddling
+ * with constants until the result observed on the scope was good enough
+ * for 20kHz, 50kHz, 100kHz, 200kHz, 300kHz and 400kHz. It should be
+ * possible to assume the algorithm works for other frequencies as well.
+ *
+ * Note it was necessary to cap the frequency on both ends as it's not
+ * possible to configure completely arbitrary frequency for the I2C bus
+ * clock.
+ */
+ uint32_t clk = mxc_get_clock(MXC_XTAL_CLK);
+ uint32_t base = ((clk / speed) - 38) / 2;
+ uint16_t high_count = base + 3;
+ uint16_t low_count = base - 3;
+ uint16_t rcv_count = (high_count * 3) / 4;
+ uint16_t xmit_count = low_count / 4;
+
+ if (speed > 540000) {
+ printf("MXS I2C: Speed too high (%d Hz)\n", speed);
+ return -EINVAL;
+ }
- mxs_i2c_reset();
-
- switch (speed) {
- case 100000:
- writel((0x0078 << I2C_TIMING0_HIGH_COUNT_OFFSET) |
- (0x0030 << I2C_TIMING0_RCV_COUNT_OFFSET),
- &i2c_regs->hw_i2c_timing0);
- writel((0x0080 << I2C_TIMING1_LOW_COUNT_OFFSET) |
- (0x0030 << I2C_TIMING1_XMIT_COUNT_OFFSET),
- &i2c_regs->hw_i2c_timing1);
- break;
- case 400000:
- writel((0x000f << I2C_TIMING0_HIGH_COUNT_OFFSET) |
- (0x0007 << I2C_TIMING0_RCV_COUNT_OFFSET),
- &i2c_regs->hw_i2c_timing0);
- writel((0x001f << I2C_TIMING1_LOW_COUNT_OFFSET) |
- (0x000f << I2C_TIMING1_XMIT_COUNT_OFFSET),
- &i2c_regs->hw_i2c_timing1);
- break;
- default:
- printf("MXS I2C: Invalid speed selected (%d Hz)\n", speed);
- return;
+ if (speed < 12000) {
+ printf("MXS I2C: Speed too low (%d Hz)\n", speed);
+ return -EINVAL;
}
- writel((0x0015 << I2C_TIMING2_BUS_FREE_OFFSET) |
- (0x000d << I2C_TIMING2_LEADIN_COUNT_OFFSET),
+ writel((high_count << 16) | rcv_count, &i2c_regs->hw_i2c_timing0);
+ writel((low_count << 16) | xmit_count, &i2c_regs->hw_i2c_timing1);
+
+ writel((0x0030 << I2C_TIMING2_BUS_FREE_OFFSET) |
+ (0x0030 << I2C_TIMING2_LEADIN_COUNT_OFFSET),
&i2c_regs->hw_i2c_timing2);
+ return 0;
+}
+
+unsigned int i2c_get_bus_speed(void)
+{
+ struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
+ uint32_t clk = mxc_get_clock(MXC_XTAL_CLK);
+ uint32_t timing0;
+
+ timing0 = readl(&i2c_regs->hw_i2c_timing0);
+ /*
+ * This is a reverse version of the algorithm presented in
+ * i2c_set_bus_speed(). Please refer there for details.
+ */
+ return clk / ((((timing0 >> 16) - 3) * 2) + 38);
+}
+
+void i2c_init(int speed, int slaveadd)
+{
+ mxs_i2c_reset();
+ i2c_set_bus_speed(speed);
+
return;
}
diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c
index 094305fdf..af454f901 100644
--- a/drivers/i2c/omap24xx_i2c.c
+++ b/drivers/i2c/omap24xx_i2c.c
@@ -179,7 +179,8 @@ static int i2c_read_byte(u8 devaddr, u16 regoffset, u8 alen, u8 *value)
if (status & I2C_STAT_XRDY) {
w = tmpbuf[i++];
#if !(defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX))
+ defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
+ defined(CONFIG_OMAP54XX))
w |= tmpbuf[i++] << 8;
#endif
writew(w, &i2c_base->data);
@@ -209,7 +210,8 @@ static int i2c_read_byte(u8 devaddr, u16 regoffset, u8 alen, u8 *value)
}
if (status & I2C_STAT_RRDY) {
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX)
+ defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
+ defined(CONFIG_OMAP54XX)
*value = readb(&i2c_base->data);
#else
*value = readw(&i2c_base->data);
@@ -239,7 +241,8 @@ static void flush_fifo(void)
stat = readw(&i2c_base->stat);
if (stat == I2C_STAT_RRDY) {
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX)
+ defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
+ defined(CONFIG_OMAP54XX)
readb(&i2c_base->data);
#else
readw(&i2c_base->data);
@@ -289,7 +292,8 @@ int i2c_probe(uchar chip)
if (status & I2C_STAT_RRDY) {
res = 0;
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX)
+ defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
+ defined(CONFIG_OMAP54XX)
readb(&i2c_base->data);
#else
readw(&i2c_base->data);
@@ -376,7 +380,8 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
if (status & I2C_STAT_XRDY) {
w = (i < 0) ? tmpbuf[2+i] : buffer[i];
#if !(defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX))
+ defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
+ defined(CONFIG_OMAP54XX))
w |= ((++i < 0) ? tmpbuf[2+i] : buffer[i]) << 8;
#endif
writew(w, &i2c_base->data);
diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c
index 9bc4c7f1d..90d297a28 100644
--- a/drivers/i2c/s3c24x0_i2c.c
+++ b/drivers/i2c/s3c24x0_i2c.c
@@ -27,7 +27,7 @@
*/
#include <common.h>
-#ifdef CONFIG_EXYNOS5
+#if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
#include <asm/arch/clk.h>
#include <asm/arch/cpu.h>
#else
@@ -62,7 +62,7 @@
static unsigned int g_current_bus; /* Stores Current I2C Bus */
-#ifndef CONFIG_EXYNOS5
+#if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
static int GetI2CSDA(void)
{
struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio();
@@ -121,7 +121,12 @@ static void ReadWriteByte(struct s3c24x0_i2c *i2c)
static struct s3c24x0_i2c *get_base_i2c(void)
{
-#ifdef CONFIG_EXYNOS5
+#ifdef CONFIG_EXYNOS4
+ struct s3c24x0_i2c *i2c = (struct s3c24x0_i2c *)(samsung_get_base_i2c()
+ + (EXYNOS4_I2C_SPACING
+ * g_current_bus));
+ return i2c;
+#elif defined CONFIG_EXYNOS5
struct s3c24x0_i2c *i2c = (struct s3c24x0_i2c *)(samsung_get_base_i2c()
+ (EXYNOS5_I2C_SPACING
* g_current_bus));
@@ -134,7 +139,7 @@ static struct s3c24x0_i2c *get_base_i2c(void)
static void i2c_ch_init(struct s3c24x0_i2c *i2c, int speed, int slaveadd)
{
ulong freq, pres = 16, div;
-#ifdef CONFIG_EXYNOS5
+#if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
freq = get_i2c_clk();
#else
freq = get_PCLK();
@@ -188,7 +193,7 @@ unsigned int i2c_get_bus_num(void)
void i2c_init(int speed, int slaveadd)
{
struct s3c24x0_i2c *i2c;
-#ifndef CONFIG_EXYNOS5
+#if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio();
#endif
int i;
@@ -204,7 +209,7 @@ void i2c_init(int speed, int slaveadd)
i--;
}
-#ifndef CONFIG_EXYNOS5
+#if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
if ((readl(&i2c->iicstat) & I2CSTAT_BSY) || GetI2CSDA() == 0) {
#ifdef CONFIG_S3C2410
ulong old_gpecon = readl(&gpio->gpecon);
@@ -248,7 +253,7 @@ void i2c_init(int speed, int slaveadd)
writel(old_gpecon, &gpio->pgcon);
#endif
}
-#endif /* #ifndef CONFIG_EXYNOS5 */
+#endif /* #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) */
i2c_ch_init(i2c, speed, slaveadd);
}
diff --git a/drivers/i2c/soft_i2c.c b/drivers/i2c/soft_i2c.c
index 1595c0714..ae3c57392 100644
--- a/drivers/i2c/soft_i2c.c
+++ b/drivers/i2c/soft_i2c.c
@@ -30,6 +30,9 @@
#include <ioports.h>
#include <asm/io.h>
#endif
+#if defined(CONFIG_AVR32)
+#include <asm/arch/portmux.h>
+#endif
#if defined(CONFIG_AT91FAMILY)
#include <asm/io.h>
#include <asm/arch/hardware.h>
diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
index f5f43a6dd..1f8955a0f 100644
--- a/drivers/serial/serial.c
+++ b/drivers/serial/serial.c
@@ -22,6 +22,7 @@
*/
#include <common.h>
+#include <environment.h>
#include <serial.h>
#include <stdio_dev.h>
#include <post.h>
@@ -32,6 +33,11 @@ DECLARE_GLOBAL_DATA_PTR;
static struct serial_device *serial_devices;
static struct serial_device *serial_current;
+/*
+ * Table with supported baudrates (defined in config_xyz.h)
+ */
+static const unsigned long baudrate_table[] = CONFIG_SYS_BAUDRATE_TABLE;
+#define N_BAUDRATES (sizeof(baudrate_table) / sizeof(baudrate_table[0]))
/**
* serial_null() - Void registration routine of a serial driver
@@ -46,6 +52,70 @@ static void serial_null(void)
}
/**
+ * on_baudrate() - Update the actual baudrate when the env var changes
+ *
+ * This will check for a valid baudrate and only apply it if valid.
+ */
+static int on_baudrate(const char *name, const char *value, enum env_op op,
+ int flags)
+{
+ int i;
+ int baudrate;
+
+ switch (op) {
+ case env_op_create:
+ case env_op_overwrite:
+ /*
+ * Switch to new baudrate if new baudrate is supported
+ */
+ baudrate = simple_strtoul(value, NULL, 10);
+
+ /* Not actually changing */
+ if (gd->baudrate == baudrate)
+ return 0;
+
+ for (i = 0; i < N_BAUDRATES; ++i) {
+ if (baudrate == baudrate_table[i])
+ break;
+ }
+ if (i == N_BAUDRATES) {
+ if ((flags & H_FORCE) == 0)
+ printf("## Baudrate %d bps not supported\n",
+ baudrate);
+ return 1;
+ }
+ if ((flags & H_INTERACTIVE) != 0) {
+ printf("## Switch baudrate to %d"
+ " bps and press ENTER ...\n", baudrate);
+ udelay(50000);
+ }
+
+ gd->baudrate = baudrate;
+#if defined(CONFIG_PPC) || defined(CONFIG_MCF52x2)
+ gd->bd->bi_baudrate = baudrate;
+#endif
+
+ serial_setbrg();
+
+ udelay(50000);
+
+ if ((flags & H_INTERACTIVE) != 0)
+ while (1) {
+ if (getc() == '\r')
+ break;
+ }
+
+ return 0;
+ case env_op_delete:
+ printf("## Baudrate may not be deleted\n");
+ return 1;
+ default:
+ return 0;
+ }
+}
+U_BOOT_ENV_CALLBACK(baudrate, on_baudrate);
+
+/**
* serial_initfunc() - Forward declare of driver registration routine
* @name: Name of the real driver registration routine.
*