Do not reset GPIO1 at boot-up because GPIO 7 in GPIO1 block is used on
OMAP4460 PandaBoard-ES to select voltage register in TPS62361 which
supplies VDD_MPU.
Without this, OMAP4460 PandaBoard-ES boards fail to boot-up because
MPU voltage switches over to VSET0 voltage value (boot voltage) which
is not sufficient to operate the device at OPP100.
Signed-off-by: Nishanth Menon <[email protected]>
---
As explained here: http://marc.info/?l=u-boot&m=133066647800872&w=2
GPIO1 reset causes PandaBoard-ES to stop functioning.
This depends on Patch series from Rajendra:
http://marc.info/?l=linux-doc&m=138131355520116&w=2
Applies on Benoit's for_13/dts branch:
https://git.kernel.org/cgit/linux/kernel/git/bcousson/linux-omap-dt.git/log/?h=for_3.13/dts
Tested on PandaBoard-ES without the u-boot uenv hack
arch/arm/boot/dts/omap4-panda-es.dts | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/arm/boot/dts/omap4-panda-es.dts b/arch/arm/boot/dts/omap4-panda-es.dts
index 56c4354..816d1c9 100644
--- a/arch/arm/boot/dts/omap4-panda-es.dts
+++ b/arch/arm/boot/dts/omap4-panda-es.dts
@@ -62,3 +62,7 @@
gpios = <&gpio1 8 GPIO_ACTIVE_HIGH>;
};
};
+
+&gpio1 {
+ ti,no-reset-on-init;
+};
--
1.7.9.5
* Nishanth Menon <[email protected]> [131010 09:53]:
> Do not reset GPIO1 at boot-up because GPIO 7 in GPIO1 block is used on
> OMAP4460 PandaBoard-ES to select voltage register in TPS62361 which
> supplies VDD_MPU.
>
> Without this, OMAP4460 PandaBoard-ES boards fail to boot-up because
> MPU voltage switches over to VSET0 voltage value (boot voltage) which
> is not sufficient to operate the device at OPP100.
Is this needs as a fix for the -rc series?
Tony
> Signed-off-by: Nishanth Menon <[email protected]>
> ---
> As explained here: http://marc.info/?l=u-boot&m=133066647800872&w=2
>
> GPIO1 reset causes PandaBoard-ES to stop functioning.
> This depends on Patch series from Rajendra:
> http://marc.info/?l=linux-doc&m=138131355520116&w=2
> Applies on Benoit's for_13/dts branch:
> https://git.kernel.org/cgit/linux/kernel/git/bcousson/linux-omap-dt.git/log/?h=for_3.13/dts
>
> Tested on PandaBoard-ES without the u-boot uenv hack
>
> arch/arm/boot/dts/omap4-panda-es.dts | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/arch/arm/boot/dts/omap4-panda-es.dts b/arch/arm/boot/dts/omap4-panda-es.dts
> index 56c4354..816d1c9 100644
> --- a/arch/arm/boot/dts/omap4-panda-es.dts
> +++ b/arch/arm/boot/dts/omap4-panda-es.dts
> @@ -62,3 +62,7 @@
> gpios = <&gpio1 8 GPIO_ACTIVE_HIGH>;
> };
> };
> +
> +&gpio1 {
> + ti,no-reset-on-init;
> +};
> --
> 1.7.9.5
>
> --
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On 10/10/2013 11:47 AM, Tony Lindgren wrote:
> * Nishanth Menon <[email protected]> [131010 09:53]:
>> Do not reset GPIO1 at boot-up because GPIO 7 in GPIO1 block is used on
>> OMAP4460 PandaBoard-ES to select voltage register in TPS62361 which
>> supplies VDD_MPU.
>>
>> Without this, OMAP4460 PandaBoard-ES boards fail to boot-up because
>> MPU voltage switches over to VSET0 voltage value (boot voltage) which
>> is not sufficient to operate the device at OPP100.
>
> Is this needs as a fix for the -rc series?
Nope, this is not a regression recently introduced, has been in since
day one of Panda-ES support. Further, we still have decision pending
on the dependent series from Rajendra[1] - will be good to see it go
in along with AM335x-EVM.
[1] http://marc.info/?t=138131368300005&r=1&w=2
--
Regards,
Nishanth Menon
Hi Nishanth,
On 10/10/2013 18:44, Nishanth Menon wrote:
> Do not reset GPIO1 at boot-up because GPIO 7 in GPIO1 block is used on
> OMAP4460 PandaBoard-ES to select voltage register in TPS62361 which
> supplies VDD_MPU.
>
> Without this, OMAP4460 PandaBoard-ES boards fail to boot-up because
> MPU voltage switches over to VSET0 voltage value (boot voltage) which
> is not sufficient to operate the device at OPP100.
>
> Signed-off-by: Nishanth Menon <[email protected]>
> ---
> As explained here: http://marc.info/?l=u-boot&m=133066647800872&w=2
>
> GPIO1 reset causes PandaBoard-ES to stop functioning.
> This depends on Patch series from Rajendra:
> http://marc.info/?l=linux-doc&m=138131355520116&w=2
> Applies on Benoit's for_13/dts branch:
> https://git.kernel.org/cgit/linux/kernel/git/bcousson/linux-omap-dt.git/log/?h=for_3.13/dts
I've just applied it after Rajendra's series.
Thanks,
Benoit
>
> Tested on PandaBoard-ES without the u-boot uenv hack
>
> arch/arm/boot/dts/omap4-panda-es.dts | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/arch/arm/boot/dts/omap4-panda-es.dts b/arch/arm/boot/dts/omap4-panda-es.dts
> index 56c4354..816d1c9 100644
> --- a/arch/arm/boot/dts/omap4-panda-es.dts
> +++ b/arch/arm/boot/dts/omap4-panda-es.dts
> @@ -62,3 +62,7 @@
> gpios = <&gpio1 8 GPIO_ACTIVE_HIGH>;
> };
> };
> +
> +&gpio1 {
> + ti,no-reset-on-init;
> +};
>
--
Beno?t Cousson
BayLibre
Embedded Linux Technology Lab
http://www.baylibre.com