[U-Boot] [PATCH v5 05/18] arm: MediaTek: add basic support for MT7623 boards

[Simon Glass]

Hi Weijie,

On 15 November 2018 at 23:08, Weijie Gao <weijie.gao at mediatek.com> wrote:
> On Thu, 2018-11-15 at 11:21 -0800, Simon Glass wrote:
>> Hi,
>>
>> On 14 November 2018 at 18:07, Ryder Lee <ryder.lee at mediatek.com> wrote:
>> > From: Weijie Gao <weijie.gao at mediatek.com>
>> >
>> > This adds a general board file based on MT7623 SoCs from MediaTek.
>> >
>> > As this u-boot is loaded by MTK proprietary preloader, there is no
>> > low level initializtion codes.
>> >
>> > Signed-off-by: Weijie Gao <weijie.gao at mediatek.com>
>> > Signed-off-by: Ryder Lee <ryder.lee at mediatek.com>
>> > Tested-by: Matthias Brugger <matthias.bgg at gmail.com>
>> > ---
>> > Changes since v5: None
>> > Changes since v4:
>> > -Add gd->bd->bi_boot_params for legacy method - ATAGs.
>> > ---
>> >  arch/arm/mach-mediatek/Kconfig                | 13 ++++
>> >  arch/arm/mach-mediatek/Makefile               |  1 +
>> >  arch/arm/mach-mediatek/mt7623/Makefile        |  4 ++
>> >  arch/arm/mach-mediatek/mt7623/init.c          | 54 +++++++++++++++
>> >  arch/arm/mach-mediatek/mt7623/lowlevel_init.S | 22 ++++++
>> >  arch/arm/mach-mediatek/mt7623/preloader.h     | 99
+++++++++++++++++++++++++++
>> >  board/mediatek/mt7623/Kconfig                 | 13 ++++
>> >  board/mediatek/mt7623/MAINTAINERS             |  7 ++
>> >  board/mediatek/mt7623/Makefile                |  3 +
>> >  board/mediatek/mt7623/mt7623_rfb.c            | 16 +++++
>> >  configs/mt7623n_bpir2_defconfig               | 54 +++++++++++++++
>> >  include/configs/mt7623.h                      | 56 +++++++++++++++
>> >  12 files changed, 342 insertions(+)
>> >  create mode 100644 arch/arm/mach-mediatek/mt7623/Makefile
>> >  create mode 100644 arch/arm/mach-mediatek/mt7623/init.c
>> >  create mode 100644 arch/arm/mach-mediatek/mt7623/lowlevel_init.S
>> >  create mode 100644 arch/arm/mach-mediatek/mt7623/preloader.h
>> >  create mode 100644 board/mediatek/mt7623/Kconfig
>> >  create mode 100644 board/mediatek/mt7623/MAINTAINERS
>> >  create mode 100644 board/mediatek/mt7623/Makefile
>> >  create mode 100644 board/mediatek/mt7623/mt7623_rfb.c
>> >  create mode 100644 configs/mt7623n_bpir2_defconfig
>> >  create mode 100644 include/configs/mt7623.h
>>
>> Can this use the bloblist feature which should land soon?
>>
>> For now, see dm/spl-working.
>>
>> Regards,
>> Simon
>
> Hi Simon,
>
> I've read the code for spl handoff. It's a good way though but
> unfortunately it cannot be applied to the MT7623 boards.
>
> The reason is that MT7623 uses a MediaTek proprietary preloader which
> has the same function as the U-Boot SPL. But the preloader is
> close-sourced (by company policy) and only available in binary release.
> This means we can't use a real U-Boot SPL to replace the preloader.

Can you work to get U-Boot SPL running on the chip?

What is the reason for the proprietary SPL?

>
> At present this chip has already been used in many products. We can't
> either release a different preloader which introduces compatibility
> issues.

What sort of compatibility issues? I cannot see any advantage with a
proprietary SPL.

>
> So the conclusion is that we cannot use the bloblist feature for this
> SoC.

Regards,
Simon