[U-Boot] [PATCH] exynos: Adjust the starting MIF voltage to 1.05v

Some Exynos5250 silicon may require 1.05v on the MIF to be stable, so to be safe we can default to 1.05v instead of 1.00v. This can be set optimally later in the boot process by the kernel.
The 0x6 value for 1.05v comes from the MAX77686 datasheet.
Signed-off-by: Bernie Thompson bhthompson@chromium.org --- board/samsung/smdk5250/smdk5250.c | 2 +- include/power/max77686_pmic.h | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/board/samsung/smdk5250/smdk5250.c b/board/samsung/smdk5250/smdk5250.c index 217c6df..2cea844 100644 --- a/board/samsung/smdk5250/smdk5250.c +++ b/board/samsung/smdk5250/smdk5250.c @@ -182,7 +182,7 @@ int power_init_board(void)
/* VDD_MIF */ if (pmic_reg_write(p, MAX77686_REG_PMIC_BUCK1OUT, - MAX77686_BUCK1OUT_1V)) { + MAX77686_BUCK1OUT_1_05V)) { debug("%s: PMIC %d register write failed\n", __func__, MAX77686_REG_PMIC_BUCK1OUT); return -1; diff --git a/include/power/max77686_pmic.h b/include/power/max77686_pmic.h index fdc7ca9..1c374a9 100644 --- a/include/power/max77686_pmic.h +++ b/include/power/max77686_pmic.h @@ -157,6 +157,8 @@ enum {
/* Buck1 1 volt value */ #define MAX77686_BUCK1OUT_1V 0x5 +/* Buck1 1.05 volt value */ +#define MAX77686_BUCK1OUT_1_05V 0x6 #define MAX77686_BUCK1CTRL_EN (3 << 0) /* Buck2 1.3 volt value */ #define MAX77686_BUCK2DVS1_1_3V 0x38

On Mon, Apr 15, 2013 at 11:34 AM, Bernie Thompson bhthompson@chromium.org wrote:
Some Exynos5250 silicon may require 1.05v on the MIF to be stable, so to be safe we can default to 1.05v instead of 1.00v. This can be set optimally later in the boot process by the kernel.
The 0x6 value for 1.05v comes from the MAX77686 datasheet.
Signed-off-by: Bernie Thompson bhthompson@chromium.org
Acked-by: Simon Glass sjg@chromium.org
board/samsung/smdk5250/smdk5250.c | 2 +- include/power/max77686_pmic.h | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/board/samsung/smdk5250/smdk5250.c b/board/samsung/smdk5250/smdk5250.c index 217c6df..2cea844 100644 --- a/board/samsung/smdk5250/smdk5250.c +++ b/board/samsung/smdk5250/smdk5250.c @@ -182,7 +182,7 @@ int power_init_board(void)
/* VDD_MIF */ if (pmic_reg_write(p, MAX77686_REG_PMIC_BUCK1OUT,
MAX77686_BUCK1OUT_1V)) {
MAX77686_BUCK1OUT_1_05V)) { debug("%s: PMIC %d register write failed\n", __func__, MAX77686_REG_PMIC_BUCK1OUT); return -1;
diff --git a/include/power/max77686_pmic.h b/include/power/max77686_pmic.h index fdc7ca9..1c374a9 100644 --- a/include/power/max77686_pmic.h +++ b/include/power/max77686_pmic.h @@ -157,6 +157,8 @@ enum {
/* Buck1 1 volt value */ #define MAX77686_BUCK1OUT_1V 0x5 +/* Buck1 1.05 volt value */ +#define MAX77686_BUCK1OUT_1_05V 0x6 #define MAX77686_BUCK1CTRL_EN (3 << 0) /* Buck2 1.3 volt value */
#define MAX77686_BUCK2DVS1_1_3V 0x38
1.8.1.3
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On 12/05/13 03:50, Simon Glass wrote:
On Mon, Apr 15, 2013 at 11:34 AM, Bernie Thompson bhthompson@chromium.org wrote:
Some Exynos5250 silicon may require 1.05v on the MIF to be stable, so to be safe we can default to 1.05v instead of 1.00v. This can be set optimally later in the boot process by the kernel.
The 0x6 value for 1.05v comes from the MAX77686 datasheet.
Signed-off-by: Bernie Thompson bhthompson@chromium.org
Acked-by: Simon Glass sjg@chromium.org
board/samsung/smdk5250/smdk5250.c | 2 +- include/power/max77686_pmic.h | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-)
applied to u-boot-samsung.
Thanks, Minkyu Kang.
participants (3)
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Bernie Thompson
-
Minkyu Kang
-
Simon Glass