[v2,1/1] board: add support for RIoTboard

This is a small development board, based on Freescale IMX6 Solo SoC
(single core ARM Cortex-A9). The board has excellent support in mainline
U-Boot and Linux.

Signed-off-by: Nikolay Dimitrov <picmaster@mail.bg>
---
Changes v1 -> v2:
  - added support for extlinux, as required by U-Boot 2015.01
  - fixed some typos

 board/embest/riotboard/extlinux.conf |    6 ++++
 board/embest/riotboard/readme.txt    |   55 ++++++++++++++++++++++++++++++++++
 configs/riotboard_defconfig          |   30 +++++++++++++++++++
 3 files changed, 91 insertions(+)
 create mode 100644 board/embest/riotboard/extlinux.conf
 create mode 100644 board/embest/riotboard/readme.txt
 create mode 100644 configs/riotboard_defconfig

Dear Nikolay Dimitrov,

On Thu,  5 Mar 2015 16:31:47 +0200, Nikolay Dimitrov wrote:

> +Create 2 partitions on the SD-card using your favourite tool. Partition 1
> +should be around 32MiB, partition 2 should be big enough to hold your rootfs,
> +for example 128MiB. Here's how an example of such partition layout:
> +
> +   Device Boot      Start         End      Blocks   Id  System
> +/dev/sdX1            2048       67583       32768   83  Linux
> +/dev/sdX2           67584      329727      131072   83  Linux
> +
> +Format these SD-card partitions with your favourite filesystem:
> +
> +sudo mkfs.ext2 /dev/sdX1
> +sudo mkfs.ext2 /dev/sdX2
> +
> +Copy the kernel, device tree and extlinux configuration to SD-card partition 1:
> +
> +sudo mkdir /mnt/sdcard/
> +sudo mount /dev/sdX1 /mnt/sdcard/
> +sudo mkdir -p /mnt/sdcard/boot/extlinux/
> +sudo cp -v board/embest/riotboard/extlinux.conf /mnt/sdcard/boot/extlinux/
> +sudo cp -v uImage /mnt/sdcard/boot/
> +sudo cp -v imx6dl-riotboard.dtb /mnt/sdcard/boot/
> +sudo umount /dev/sdX1
> +
> +Then deploy your rootfs on SD-card partition 2:
> +
> +sudo mount /dev/sdX2 /mnt/sdcard/
> +sudo tar xf rootfs.tar -C /mnt/sdcard/
> +sudo umount /dev/sdX2

Is there a particular reason to have two ext2 partitions? Why not one
single partition with the rootfs, also
containing /boot/extlinux/extlinux.conf, /boot/uImage
and /boot/imx6dl-riotboard.dtb ?

Best regards,

Thomas

Hi Thomas,

On 03/05/2015 04:37 PM, Thomas Petazzoni wrote:
> Dear Nikolay Dimitrov,
>
> On Thu,  5 Mar 2015 16:31:47 +0200, Nikolay Dimitrov wrote:
>
>> +Create 2 partitions on the SD-card using your favourite tool. Partition 1
>> +should be around 32MiB, partition 2 should be big enough to hold your rootfs,
>> +for example 128MiB. Here's how an example of such partition layout:
>> +
>> +   Device Boot      Start         End      Blocks   Id  System
>> +/dev/sdX1            2048       67583       32768   83  Linux
>> +/dev/sdX2           67584      329727      131072   83  Linux
>> +
>> +Format these SD-card partitions with your favourite filesystem:
>> +
>> +sudo mkfs.ext2 /dev/sdX1
>> +sudo mkfs.ext2 /dev/sdX2
>> +
>> +Copy the kernel, device tree and extlinux configuration to SD-card partition 1:
>> +
>> +sudo mkdir /mnt/sdcard/
>> +sudo mount /dev/sdX1 /mnt/sdcard/
>> +sudo mkdir -p /mnt/sdcard/boot/extlinux/
>> +sudo cp -v board/embest/riotboard/extlinux.conf /mnt/sdcard/boot/extlinux/
>> +sudo cp -v uImage /mnt/sdcard/boot/
>> +sudo cp -v imx6dl-riotboard.dtb /mnt/sdcard/boot/
>> +sudo umount /dev/sdX1
>> +
>> +Then deploy your rootfs on SD-card partition 2:
>> +
>> +sudo mount /dev/sdX2 /mnt/sdcard/
>> +sudo tar xf rootfs.tar -C /mnt/sdcard/
>> +sudo umount /dev/sdX2
>
> Is there a particular reason to have two ext2 partitions? Why not one
> single partition with the rootfs, also
> containing /boot/extlinux/extlinux.conf, /boot/uImage
> and /boot/imx6dl-riotboard.dtb ?

Not really. Now as you're asking, I found that I'm doing this by habit
(probably inherited by some weird ARM board boot-requirements in the
past).

Would you prefer me to re-send the patch with instructions only for
single partition layout?

Kind regards,
Nikolay

Dear Nikolay Dimitrov,

On Thu, 05 Mar 2015 16:58:47 +0200, Nikolay Dimitrov wrote:

> Not really. Now as you're asking, I found that I'm doing this by habit
> (probably inherited by some weird ARM board boot-requirements in the
> past).

Yes, some boards/bootloader configuration have the limitation that the
first partition must be a FAT partition. In this case, it definitely
makes sense to have two partitions, since a Linux root filesystem can
hardly be stored in a FAT filesystem.

> Would you prefer me to re-send the patch with instructions only for
> single partition layout?

Well, in the situation of this board, where the bootloader is stored
raw and is capable of reading an ext2 filesystem, yes I believe a
single partition makes more sense.

You can ask Buildroot to install the uImage and DTB to /boot in the
root filesystem. However, for the extlinux.config file, you'll have to
add a post-build script to do this.

Best regards,

Thomas

Hi Thomas,

On 03/05/2015 05:05 PM, Thomas Petazzoni wrote:
> Dear Nikolay Dimitrov,
>
> On Thu, 05 Mar 2015 16:58:47 +0200, Nikolay Dimitrov wrote:
>
>> Not really. Now as you're asking, I found that I'm doing this by habit
>> (probably inherited by some weird ARM board boot-requirements in the
>> past).
>
> Yes, some boards/bootloader configuration have the limitation that the
> first partition must be a FAT partition. In this case, it definitely
> makes sense to have two partitions, since a Linux root filesystem can
> hardly be stored in a FAT filesystem.
>
>> Would you prefer me to re-send the patch with instructions only for
>> single partition layout?
>
> Well, in the situation of this board, where the bootloader is stored
> raw and is capable of reading an ext2 filesystem, yes I believe a
> single partition makes more sense.
>
> You can ask Buildroot to install the uImage and DTB to /boot in the
> root filesystem. However, for the extlinux.config file, you'll have to
> add a post-build script to do this.

Thanks for your comments. I think this is better than my initial
proposal. Patch is on the way.

Regards,
Nikolay