[U-Boot] [PATCH 1/3] rockchip: rk3399: add tpl support【请注意，邮件由sjg at google.com代发】

[Jagan Teki]

Hi Kever,

On Thu, Apr 18, 2019 at 12:37 PM Kever Yang <kever.yang at rock-chips.com> wrote:
>
> Hi Simon,
>
>
> On 04/18/2019 12:32 PM, Simon Glass wrote:
> > Hi Kever,
> >
> > On Mon, 1 Apr 2019 at 02:21, Kever Yang <kever.yang at rock-chips.com> wrote:
> >> Rockchip platform suppose to use TPL(run in SRAM) as dram init and
> >> SPL(run in DDR SDRAM) as pre-loader, so that the SPL would not be
> >> limited by SRAM size.
> >> This patch add rk3399-board-tpl.c and its common configs.
> > So this means that TPL inits SDRAM? That seems strange to me...why
> > have SPL at all, then? What is SPL supported to do on RK3399
> > platforms?
>
> The model is:
> TPL's code in SRAM, load by BOOTROM, EL3 mode(armv8) ,and focus at DDR
> SDRAM init, have code size limit by SRAM;
> SPL's code in DDR, load by BOOTROM, EL3 mode(armv8), and main feature is:
> - parse and load trust, eg, bl31, bl32, op-tee, which need to before U-Boot;
> - parse and load firmware for next stage, eg. u-boot, kernel;
> U-Boot proper code in DDR, load by SPL, EL2 mode(armv8), full feature;
>
> and we may add features like below for SPL:
> - secure verify for u-boot.itb;
> - relocate to support bl31 better;
> - boot kernel in falcon mode directly from SPL;
> - implement usb download mode(rockusb) in case u-boot is broken;
> - enable partition support to support A/B system for U-Boot;
> - more storage driver support at the same time other than mmc, eg. spi,
> nand;

Agreed.

I have tried for similar model to add falcon in rk3288.
So the TPL can boot from ROM and SPL can be from boot device sd/emmc/
etc correct?

Jagan.