[PATCH v2] ARM: dts: imx6qdl-nitrogen6x: Add SPI NOR partitions

[PATCH v2] ARM: dts: imx6qdl-nitrogen6x: Add SPI NOR partitions

[Otavio Salvador]

This adds the partitions definition for the SPI NOR to provide
backward compatibility with the documented[1] layout used with
Boundary Devices BSP.

1. https://boundarydevices.com/boot-flash-access-linux/

It exports to Linux:

 mtd0: bootloader
 mtd1: env
 mtd2: splash

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
---

Changes in v2:
 - rework labels (Fabio Estevam)
 - add read-only flags (Fabio Estevam)

 arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi b/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi
index 4bdf29169d2a..28545412577a 100644
--- a/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi
+++ b/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi
@@ -276,6 +276,26 @@
 		compatible = "sst,sst25vf016b", "jedec,spi-nor";
 		spi-max-frequency = <20000000>;
 		reg = <0>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+		partition@0 {
+			label = "bootloader";
+			reg = <0x0 0xc0000>;
+			read-only;
+		};
+
+		partition@c0000 {
+			label = "env";
+			reg = <0xc0000 0x2000>;
+			read-only;
+		};
+
+		partition@c2000 {
+			label = "splash";
+			reg = <0xc2000 0x13e000>;
+			read-only;
+		};
 	};
 };
 
-- 
2.15.0

Re: [PATCH v2] ARM: dts: imx6qdl-nitrogen6x: Add SPI NOR partitions

[Otavio Salvador]

On Fri, Nov 24, 2017 at 3:00 PM, Otavio Salvador
<otavio-fKevB0iiKLMBZ+LybsDmbA@public.gmane.org> wrote:
> This adds the partitions definition for the SPI NOR to provide
> backward compatibility with the documented[1] layout used with
> Boundary Devices BSP.
>
> 1. https://boundarydevices.com/boot-flash-access-linux/
>
> It exports to Linux:
>
>  mtd0: bootloader
>  mtd1: env
>  mtd2: splash
>
> Signed-off-by: Otavio Salvador <otavio-fKevB0iiKLMBZ+LybsDmbA@public.gmane.org>

After thinking a bit about Fabio's recommendation to use 'read-only'
to protect the partitions, I think it'd be better to use 'lock' so it
is still possible to write them on Linux but it requires a unlock
prior changing it.

In my case, I am interested in being capable of upgrading the
bootloader from Linux.

What people think?

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750
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Re: [PATCH v2] ARM: dts: imx6qdl-nitrogen6x: Add SPI NOR partitions

[Gary Bisson]

Hi Otavio,

On Sat, Nov 25, 2017 at 07:55:53AM -0200, Otavio Salvador wrote:
> On Fri, Nov 24, 2017 at 3:00 PM, Otavio Salvador
> <otavio@ossystems.com.br> wrote:
> > This adds the partitions definition for the SPI NOR to provide
> > backward compatibility with the documented[1] layout used with
> > Boundary Devices BSP.
> >
> > 1. https://boundarydevices.com/boot-flash-access-linux/
> >
> > It exports to Linux:
> >
> >  mtd0: bootloader
> >  mtd1: env
> >  mtd2: splash
> >
> > Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
> 
> After thinking a bit about Fabio's recommendation to use 'read-only'
> to protect the partitions, I think it'd be better to use 'lock' so it
> is still possible to write them on Linux but it requires a unlock
> prior changing it.
> 
> In my case, I am interested in being capable of upgrading the
> bootloader from Linux.
> 
> What people think?

Agreed, I would rather have the lock option, especially for the splash
and environment.

Regards,
Gary

Re: [PATCH v2] ARM: dts: imx6qdl-nitrogen6x: Add SPI NOR partitions

[Otavio Salvador]

On Mon, Nov 27, 2017 at 8:17 AM, Gary Bisson
<gary.bisson@boundarydevices.com> wrote:
> Hi Otavio,
>
> On Sat, Nov 25, 2017 at 07:55:53AM -0200, Otavio Salvador wrote:
>> On Fri, Nov 24, 2017 at 3:00 PM, Otavio Salvador
>> <otavio@ossystems.com.br> wrote:
>> > This adds the partitions definition for the SPI NOR to provide
>> > backward compatibility with the documented[1] layout used with
>> > Boundary Devices BSP.
>> >
>> > 1. https://boundarydevices.com/boot-flash-access-linux/
>> >
>> > It exports to Linux:
>> >
>> >  mtd0: bootloader
>> >  mtd1: env
>> >  mtd2: splash
>> >
>> > Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
>>
>> After thinking a bit about Fabio's recommendation to use 'read-only'
>> to protect the partitions, I think it'd be better to use 'lock' so it
>> is still possible to write them on Linux but it requires a unlock
>> prior changing it.
>>
>> In my case, I am interested in being capable of upgrading the
>> bootloader from Linux.
>>
>> What people think?
>
> Agreed, I would rather have the lock option, especially for the splash
> and environment.

I will prepare a new patch using the lock option on the three
partitions so we allow the user to change them but knowing it may
break the system.

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750