Hi Sandy,
On 12 August 2016 at 11:35, Sandy Patterson apatterson@sightlogix.com wrote:
On Fri, Aug 12, 2016 at 1:20 PM, Simon Glass sjg@chromium.org wrote:
Hi Ziyuan,
On 11 August 2016 at 05:35, Ziyuan Xu xzy.xu@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 docs.
@Ziyuan, I did my testing on rock2 which doesn't use OF_PLATDATA, the firefly board should see the same final size which is roughly equivalent to the current firefly SPL size.
We ran out of space in SPL. I too was afraid of using OF_PLATDATA mostly from Simon's commit message.
I would propose moving to using the BOOTROM to load U-Boot proper. You shouldn't need any of the media drivers since the BOOTROM was already able to load the SPL 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,
Regards, Simon