[PATCH] ARM: dts: omap4-panda-es: Do not reset gpio1

[PATCH] ARM: dts: omap4-panda-es: Do not reset gpio1

[Nishanth Menon]

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 <nm@ti.com>
---
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

Re: [PATCH] ARM: dts: omap4-panda-es: Do not reset gpio1

[Tony Lindgren]

* Nishanth Menon <nm@ti.com> [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 <nm@ti.com>
> ---
> 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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Re: [PATCH] ARM: dts: omap4-panda-es: Do not reset gpio1

[Nishanth Menon]

On 10/10/2013 11:47 AM, Tony Lindgren wrote:
> * Nishanth Menon <nm@ti.com> [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

Re: [PATCH] ARM: dts: omap4-panda-es: Do not reset gpio1

[Benoit Cousson]

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 <nm@ti.com>
> ---
> 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;
> +};
>


-- 
Benoît Cousson
BayLibre
Embedded Linux Technology Lab
www.baylibre.com