[U-Boot] [PATCH v2 2/3] spl: add relocation support【请注意，邮件由sjg at google.com代发】

[Simon Glass]

Hi,

On Tue, 28 May 2019 at 09:47, Andy Yan <andy.yan at rock-chips.com> wrote:
>
> Hi Simon:
>
> On 2019/5/23 上午3:39, Simon Glass wrote:
>
> Hi Andy,
>
> On Tue, 21 May 2019 at 19:43, Andy Yan <andyshrk at gmail.com> wrote:
>
> Hi Andre:
>
> Andre Przywara <andre.przywara at arm.com> 于2019年5月20日周一 下午11:59写道：
>
> On Mon, 20 May 2019 14:34:01 +0800
> Andy Yan <andy.yan at rock-chips.com> wrote:
>
> Hi,
>
> On 2019/5/19 上午12:26, Simon Glass wrote:
>
> Hi Andy,
>
> Instead of this could you:
>
> - move ATF?
>
> All rockchip based arm64 ATF run from the start 64KB of dram as this
> will give convenient for kernel manage the memory.
>
> This is just BL31 of ATF, right?
> ATF recently gained PIE support for BL31 [1], so by just enabling this in
> platform.mk you will get a relocatable BL31 image, with a very minimal
> runtime linker. Worked out of the box on Allwinner for me, but YMMV.
> So you could load newer ATF builds everywhere.
>
>
> This is not the root case, actually we want put ATF as close as possible to
> the start of dram, this give linux kernel convenient to manage the memory.
>
> But instead of 64KB you could put it at 32KB or 128KB. It's still in
> the first 1MB. Linux won't care, right?
>
>
>
> Does that help you?
>
> On the other hand, change the ATF load address will break the
> compatibility of the exiting firmware.
>
> I am not sure what you mean with "compatibility of existing firmware"?
> Surely you combine all the firmware components (SPL/TPL/ATF/U-Boot proper)
> into one image? And there would be no real mix and match, with older
> pre-compiled builds? So by changing the ATF base address and the load
> address in TPL at the same time you won't have issues?
>
> I mean older pre-compiled builds published by rockchip rkbin [1], many
> projects and popular boards directly use this , for example Armbian. How to
> change the base address of the pre-build binary?
>  [1] https://github.com/rockchip-linux/rkbin
>
> Perhaps I am misunderstanding your intent here, but mainline U-Boot
> should not be bound to the design decisions of old closed-source
> binaries.
>
> Indeed rockchip have submit the ATF support for rockchip platforms to ATF mainline. But the situation is: we see many people like  directly use the pre-build binary from rkbin, they are used on many popular boards and projects. Armbian is one of the example for this[0] , it use mainline u-boot, but use atf from rkbin for  some boards.
>
> So we are really care about the compatibility.

OK I understand that. But perhaps for your newer chips you can start
using U-Boot SPL instead of rkbin? Then, we can move away from the
limitations.



>
> [0]https://github.com/armbian/build/blob/master/config/sources/rockchip64.conf
>
> [...]
>

Regards,
Simon