[PATCH 0/5] sunxi: remove lowlevel_init

[Jesse Taube]

On 1/24/22 20:15, Andre Przywara wrote:
> For a long time the Allwinner platform was using the lowlevel_init()
> routine in U-Boot's boot process, even though there did not seem to be
> a real need for that. The README file suggests it should only be used
> for "bare minimum" tasks to reach board_init_f(). The routines called
> in arch/arm/mach-sunxi/board.c:s_init() did nothing that really
> warranted the early and special execution. Since we always run with an
> SPL, the board_init_f() routine in there seems to be the right place
> for early peripherals initialisation.
> Having those routines in s_init() actually forced other parts of U-Boot
> to follow suit: for instance we added a lowlevel_init() function to the
> armv8 side, just for sunxi. The same game seems to repeat for the
> ARM9 support we need for the F1C100s chip, and possibly for the RISC-V
> part as well.
> 
> To avoid this and to cleanup some code on the way, remove the need for
> lowlevel_init for sunxi completely, by:
> - moving the early peripheral init (clocks, timer, pinmux) to
>    board_init_f(). This also avoids executing those bits a second time when
>    we boot up U-Boot proper. (patch 1/5)
> - move the "SRAM setup" bits for just a few old SoCs into a separate file,
>    and include this only if needed. (patch 3/5)
> - move the ACTLR.SMPEN bit setting from board.c into start.S, because we
>    actually need to set this bit early. Other platforms should be able to
>    scrap their own copies and piggy back on this change. (patch 2/5)
> This allows us to actually remove the lowlevel_init.S file from armv8 in
> patch 4/5, as sunxi was the only user.
> For good measure, we also clean up some bits in sunxi_common.h. (patch 5/5)
> 
> I compile tested this for all sunxi boards, and boot tested (into Linux) on
> Pine64, PineH64, BananaPi M1, OrangePi Zero. But there is a high chance of
> something breaking, so please give it a good shake on whatever Allwinner
> hardware you have access to.
> 
> Thanks,
> Andre
> 
> Andre Przywara (5):
>    sunxi: move non-essential code out of s_init()
>    sunxi: move Cortex SMPEN setting into start.S
>    sunxi: move early "SRAM setup" into separate file
>    armv8: remove no longer needed lowlevel_init.S
>    sunxi-common.h: remove pointless #ifdefs
> 
>   arch/arm/Kconfig                   |  3 --
>   arch/arm/cpu/armv7/Kconfig         |  7 +++
>   arch/arm/cpu/armv7/start.S         | 11 +++++
>   arch/arm/cpu/armv7/sunxi/Makefile  |  3 ++
>   arch/arm/cpu/armv7/sunxi/sram.c    | 45 +++++++++++++++++
>   arch/arm/cpu/armv8/Makefile        |  1 -
>   arch/arm/cpu/armv8/lowlevel_init.S | 43 ----------------
>   arch/arm/mach-sunxi/Kconfig        |  2 -
>   arch/arm/mach-sunxi/board.c        | 78 ++++++++----------------------
>   include/configs/sunxi-common.h     |  7 ---
>   10 files changed, 86 insertions(+), 114 deletions(-)
>   create mode 100644 arch/arm/cpu/armv7/sunxi/sram.c
>   delete mode 100644 arch/arm/cpu/armv8/lowlevel_init.S
> 

Tested-By: Jesse Taube <Mr.Bossman075 at gmail.com>

Tested on Lamobo_R1_defconfig.

Thanks,
	Jesse Taube