On 12 August 2016 at 11:35, Sandy Patterson <apatter...@sightlogix.com> wrote:
> On Fri, Aug 12, 2016 at 1:20 PM, Simon Glass <s...@chromium.org> wrote:
>> Hi Ziyuan,
>> On 11 August 2016 at 05:35, Ziyuan Xu <xzy...@rock-chips.com> wrote:
>> > On 2016年08月11日 19:31, Sandy Patterson wrote:
>> >> Simon,
>> >> I am trying to format a patch to disable MMC in the SPL if booting main
>> >> u-boot using BOOTROM, therefore the SPL MMC isn't needed.
>> >> Is the best solution to wrap every header file (rock2.h
>> >> firefly-rk3288.h,
>> >> etc) with ifdefs on the BACK_TO_BROM define? Or would it be better to
>> >> move
>> >> the SPL MMC define into rk3288-common.h and just have chromebook_jerry
>> >> undef
>> >> it like it does the SPL GPIO code.
>> >> With that change, enabling BOOT_TO_BROM shrinks the spl from 32K to
>> >> 23K.
>> > Note that, firefly-rk3288 use OF_PLATDATA, we will use
>> > u-boot-spl-no-dtb.bin
>> > instead of u-boot-spl-dtb.bin, and the size of u-boot-spl-no-dtb.bin is
>> > almost 23K.
>> > @Simon, I think we will update doc/README.rockchip if you insist on
>> > OF_PLATDATA for firefly-rk3288. we no longer use u-boot-spl-dtb.bin.:-)
>> I don't insist :-)
>> I really don't like OF_PLATDATA. But it cuts the size down a lot
>> (~6KB) and we are otherwise always running out of space on rk3288.
>> If there is a better idea, let's have it. Otherwise, yes we can update the
> @Ziyuan, I did my testing on rock2 which doesn't use OF_PLATDATA, the
> board should see the same final size which is roughly equivalent to the
> firefly SPL size.
> We ran out of space in SPL. I too was afraid of using OF_PLATDATA mostly
> Simon's commit message.
> I would propose moving to using the BOOTROM to load U-Boot proper. You
> need any of the media drivers since the BOOTROM was already able to load the
> it should be fine loading the full U-Boot.
> I get 9K from removing MMC from rock2. I'm happy to write a patch that
> applies this logic
> to the remainder of the rk3288 boards if that's the way you'd like to go.
> You could test it by
> enabling the BOOT_TO_BROM config.
My concern with the Rockchip back-to-brom feature is that then U-Boot
cannot load U-Boot normally as SPL likes to do. I think it is fine
when we are short on space, but OF_PLATDATA fixes that.
So I think the back-to-rom feature need to be optional on boards which
don't have to use it, since it uses a non-standard boot approach,
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