[U-Boot] [RFC PATCH 03/11] spl: fit: use U-Boot device tree when FIT image has no device tree

[Bin Meng]

On Mon, Jul 22, 2019 at 2:00 AM Lukas Auer
<lukas.auer at aisec.fraunhofer.de> wrote:
>
> As part of the SPL FIT boot flow, the device tree is appended to U-Boot
> proper. The device tree is used to record information on the loadables
> to make them available to the SPL framework and U-Boot proper. Depending
> on the U-Boot device tree provider, the FIT image might not include a
> device tree. Information on the loadables is missing in this case.
>
> When booting via firmware bundled with the FIT image, U-Boot SPL loads
> the firmware binary and U-Boot proper before starting the firmware. The
> firmware, in turn, is responsible for starting U-Boot proper.
> Information on the memory location of the U-Boot proper loadable must be
> available to the SPL framework so that it can be passed to the firmware
> binary. To support this use case when no device tree is found in the FIT
> image, fall back to the U-Boot device tree in this situation.
>
> At the same time, update the comment to remove the note that the
> destination address must be aligned to ARCH_DMA_MINALIGN. Alignment is
> only required as an intermediate step when reading external data. This
> is automatically handled by spl_fit_append_fdt(). After reading the
> external data, it is copied to the specified address, which does not
> have to be aligned to ARCH_DMA_MINALIGN.
>
> Signed-off-by: Lukas Auer <lukas.auer at aisec.fraunhofer.de>
> ---
>
>  common/spl/spl_fit.c | 37 ++++++++++++++++++++++++-------------
>  1 file changed, 24 insertions(+), 13 deletions(-)
>

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
Tested-by: Bin Meng <bmeng.cn at gmail.com>