[U-Boot] [PATCHv2] da850: Add instructions to copy AIS image to NAND

[Sekhar Nori]

Hi Axel,

On Friday 17 March 2017 09:25 PM, Axel Haslam wrote:
> Add instructions to write an AIS image to NAND
> by using the u-boot nand tools.
> 
> Signed-off-by: Axel Haslam <ahaslam at baylibre.com>
> ---
> Changes in V2:
> - add erase command before write
> - Add write info when MTD partitions are defined
> 
>  board/davinci/da8xxevm/README.da850 | 41 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 41 insertions(+)
> 
> diff --git a/board/davinci/da8xxevm/README.da850 b/board/davinci/da8xxevm/README.da850
> index 29cb4ec..519267e 100644
> --- a/board/davinci/da8xxevm/README.da850
> +++ b/board/davinci/da8xxevm/README.da850
> @@ -47,6 +47,47 @@ U-Boot > sf erase 0 +320000
>  U-Boot > tftp u-boot.ais
>  U-Boot > sf write c0700000 0 $filesize
>  
> +Flashing the images to NAND
> +===========================
> +The AIS image can be written to NAND using the u-boot "nand" commands.
> +
> +Example:
> +
> +OMAPL138_LCDK requires the AIS image to be written to the second block of
> +the NAND flash.
> +
> +From the "nand info" command we see that the second block would start at
> +offset 0x20000:
> +
> +  U-Boot > nand info
> +      sector size      128 KiB (0x20000)
> +      Page size       2048 b
> +
> +From the tftp command we see that we need to copy 0x74908 bytes from
> +memory address 0xc0700000 (0x75000 if we align a page of 2048):
> +
> +  U-Boot > tftp u-boot.ais
> +      Load address: 0xc0700000
> +      Bytes transferred = 477448 (74908 hex)
> +
> +The commands to write the image from memory to NAND would be:
> +
> +  U-Boot > nand erase 0x20000 0x75000
> +  U-Boot > nand write 0xc0700000 0x20000 0x75000
> +
> +Alternatively, MTD partitions may be defined. Using "mtdparts" to
> +conveniently have a bootloader partition starting at the second block
> +(offset 0x20000):
> +
> +  setenv mtdids nand0=davinci_nand.0
> +  setenv mtdparts mtdparts=davinci_nand.0:128k(bootenv),2m(bootloader)
> +
> +In this case the commands would be simplified to:
> +
> +  U-Boot > tftp u-boot.ais
> +  U-Boot > nand erase.part bootloader
> +  U-Boot > nand write 0xc0700000 bootloader

Looks good to me now.

Perhaps the mtdparts setting above can be part of the default
environment itself ? So the additional step of setting them up can be
avoided. But that will be a separate patch.

Thanks,
Sekhar