sunxi: fix DCDC2 output in CHIP_defconfig
PATCH 1/1 sunxi: fix DCDC2 output in CHIP_defconfig
From: Boris Brezillon <[email protected]>
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.
--- configs/CHIP_defconfig | 1 - 1 file changed, 1 deletion(-)
configs/CHIP_defconfig +0 -1
@@ -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
Signature · 1 line
2.7.1
PATCH 1/1 sunxi: fix DCDC2 output in CHIP_defconfig
Quoted 4 lines · On Mon, 7 Mar 2016 13:44:11 +0100 Maxime Ripard…
From: Boris Brezillon <[email protected]>
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?
Quoted 20 lines
Rely on the default value specified in the
Kconfigentry.Signed-off-by Boris Brezillon <[email protected]>Signed-off-by Maxime Ripard <[email protected]>--- configs/CHIP_defconfig | 1 - 1 file changed, 1 deletion(-)configs/CHIP_defconfig +0
-1@@ -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
Signature · 2 lines
Best regards, Siarhei Siamashka
PATCH 1/1 sunxi: fix DCDC2 output in CHIP_defconfig
Quoted 11 lines · Siarhei Siamashka
Quoted 4 lines · On Mon, 7 Mar 2016 13:44:11 +0100 Maxime Ripard…
From: Boris Brezillon <[email protected]>
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/CHIPv1_0-BOM-Datasheets
But note that it's the usual datasheet from Allwinner, you don't have a list of operating points.
Quoted 1 line
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
Signature · 10 lines
Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: <http://lists.denx.de/pipermail/u-boot/attachments/20160308/fbe643ea/attachment.sig>
PATCH 1/1 sunxi: fix DCDC2 output in CHIP_defconfig
In reply to Maxime RipardHi,
Quoted 9 lines · Maxime Ripard
From: Boris Brezillon <[email protected]>
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
Kconfigentry.Signed-off-by Boris Brezillon <[email protected]>Signed-off-by Maxime Ripard <[email protected]>
Thanks, merged.
Regards,
Hans
Quoted 17 lines
--- configs/CHIP_defconfig | 1 - 1 file changed, 1 deletion(-)configs/CHIP_defconfig +0
-1@@ -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