[U-Boot] [PATCH] sunxi: fix DCDC2 output in CHIP_defconfig
From: Boris Brezillon boris.brezillon@free-electrons.com
Unlike the datasheet recommendation, the R8 SoC requires a 1.4V supply for its CPU when operating at 1Ghz.
Rely on the default value specified in the Kconfig entry.
Signed-off-by: Boris Brezillon boris.brezillon@free-electrons.com Signed-off-by: Maxime Ripard maxime.ripard@free-electrons.com --- configs/CHIP_defconfig | 1 - 1 file changed, 1 deletion(-)
diff --git a/configs/CHIP_defconfig b/configs/CHIP_defconfig index 78b2c511bfa2..3135d1c88e79 100644 --- a/configs/CHIP_defconfig +++ b/configs/CHIP_defconfig @@ -9,7 +9,6 @@ CONFIG_SPL=y CONFIG_SYS_EXTRA_OPTIONS="CONS_INDEX=2" # CONFIG_CMD_IMLS is not set CONFIG_CMD_GPIO=y -CONFIG_AXP_DCDC2_VOLT=1300 CONFIG_AXP_ALDO3_VOLT=3300 CONFIG_AXP_ALDO4_VOLT=3300 CONFIG_USB_MUSB_GADGET=y
On Mon, 7 Mar 2016 13:44:11 +0100 Maxime Ripard maxime.ripard@free-electrons.com wrote:
From: Boris Brezillon boris.brezillon@free-electrons.com
Unlike the datasheet recommendation, the R8 SoC requires a 1.4V supply for its CPU when operating at 1Ghz.
That's interesting. Is this R8 SoC datasheet with the Allwinner recommended cpufreq operating points available in public access somewhere?
Are they really recommending 1008MHz @1.3V there?
Rely on the default value specified in the Kconfig entry.
Signed-off-by: Boris Brezillon boris.brezillon@free-electrons.com Signed-off-by: Maxime Ripard maxime.ripard@free-electrons.com
configs/CHIP_defconfig | 1 - 1 file changed, 1 deletion(-)
diff --git a/configs/CHIP_defconfig b/configs/CHIP_defconfig index 78b2c511bfa2..3135d1c88e79 100644 --- a/configs/CHIP_defconfig +++ b/configs/CHIP_defconfig @@ -9,7 +9,6 @@ CONFIG_SPL=y CONFIG_SYS_EXTRA_OPTIONS="CONS_INDEX=2" # CONFIG_CMD_IMLS is not set CONFIG_CMD_GPIO=y -CONFIG_AXP_DCDC2_VOLT=1300 CONFIG_AXP_ALDO3_VOLT=3300 CONFIG_AXP_ALDO4_VOLT=3300 CONFIG_USB_MUSB_GADGET=y
On Mon, Mar 07, 2016 at 03:50:11PM +0200, Siarhei Siamashka wrote:
On Mon, 7 Mar 2016 13:44:11 +0100 Maxime Ripard maxime.ripard@free-electrons.com wrote:
From: Boris Brezillon boris.brezillon@free-electrons.com
Unlike the datasheet recommendation, the R8 SoC requires a 1.4V supply for its CPU when operating at 1Ghz.
That's interesting. Is this R8 SoC datasheet with the Allwinner recommended cpufreq operating points available in public access somewhere?
Yeah: https://github.com/NextThingCo/CHIP-Hardware/tree/master/CHIP%5Bv1_0%5D/CHIP...
But note that it's the usual datasheet from Allwinner, you don't have a list of operating points.
Are they really recommending 1008MHz @1.3V there?
It was a misunderstanding on our side. We thought that the nominal tension was the recommended one, and our prototypes were running just fine with it. Later samples (probably from a different batch) turned out to have memory corruptions because of the lower voltage.
Maxime
Hi,
On 07-03-16 13:44, Maxime Ripard wrote:
From: Boris Brezillon boris.brezillon@free-electrons.com
Unlike the datasheet recommendation, the R8 SoC requires a 1.4V supply for its CPU when operating at 1Ghz.
Rely on the default value specified in the Kconfig entry.
Signed-off-by: Boris Brezillon boris.brezillon@free-electrons.com Signed-off-by: Maxime Ripard maxime.ripard@free-electrons.com
Thanks, merged.
Regards,
Hans
configs/CHIP_defconfig | 1 - 1 file changed, 1 deletion(-)
diff --git a/configs/CHIP_defconfig b/configs/CHIP_defconfig index 78b2c511bfa2..3135d1c88e79 100644 --- a/configs/CHIP_defconfig +++ b/configs/CHIP_defconfig @@ -9,7 +9,6 @@ CONFIG_SPL=y CONFIG_SYS_EXTRA_OPTIONS="CONS_INDEX=2" # CONFIG_CMD_IMLS is not set CONFIG_CMD_GPIO=y -CONFIG_AXP_DCDC2_VOLT=1300 CONFIG_AXP_ALDO3_VOLT=3300 CONFIG_AXP_ALDO4_VOLT=3300 CONFIG_USB_MUSB_GADGET=y
participants (3)
-
Hans de Goede -
Maxime Ripard -
Siarhei Siamashka