[U-Boot] Booting on RK3399

[Simon Glass]

HI Mark,

On Wed, 2 Jan 2019 at 18:50, Mark Kettenis <mark.kettenis at xs4all.nl> wrote:
>
> > From: Simon Glass <sjg at chromium.org>
> > Date: Wed, 2 Jan 2019 18:15:31 -0700
> >
> > Hi Kever,
> >
> > I have a firefly-rk3399 and would like to boot it into U-Boot (as a start)
> > from an uSD card.
> >
> > Are there instructions somewhere on how to do this? I gather that I need
> > OP-TEE but not how to build it or how to put the image together. I would
> > like to have instructions in README.rockchip if possible.
> >
> > I'm planning to add U-Boot support for bob and maybe kevin (both
> > Chromebooks) but am not sure where to start. I thought the firefly might be
> > best since it is pretty common.
>
> Hi Simon,
>
> The instructions in board/u-boot/rockchip/evb_rk3399/README apply to
> the firefly-rk3399 as well.  I've successfully built working firmware
> for my board using the TF-A (ATF) 2.0 release and U-Boot SPL in the
> past that way.

Thanks for the pointer. That was the file I was looking for and I
didn't think to look at the evb.

>
> One complication with the firefly board is that by default it boots
> from eMMC, so you can't easily test new firmware by putting it on uSD
> card unless you make the eMMC unbootable somehow (e.g. by overwriting
> the start of the eMMC storage with zeroes).  In that case you can boot
> from uSD card if you write U-Boot SPL and U-Boot proper at the right
> offsets:
>
> # dd if=idbspl.img of=/dev/sd1c seek=64
> # dd if=u-boot.itb of=/dev/sd1c seek=16384
>
> (that's on OpenBSD, on Linux the device names will be different)

Yes I did that with my board, so it already boots from uSD.

>
> Haven't tested flashing eMMC with rkdeveloptool myself, but that
> should work on the firefly as well.
>
> Another complication as that the serial console speed defaults to
> 1500000 which isn't supported by all serial-to-USB chips and frankly

Yes I seem to have one that supports this, so this is fine.

> too sensitive to wire noise.  Also be aware that TF-A built from the
> official ARM sources at
>
>   https://github.com/ARM-software/arm-trusted-firmware.git
>
> defaults to 115200 (which is more reasonable IMHO).  So I have the
> following diff in my U-Boot tree.  The device tree change comes in
> handy if you want to boot from uSD card, otherwise U-Boot SPL will
> attempt to load the full U-Boot from eMMC.  Perhaps that bit should be
> committed at some point.
>
> Having support for bob would be great.  I have one, and would like to
> make OpenBSD run on it.

OK well I think I'll start with an existing board and then see what is needed.

Regards,
Simon

>
> Cheers,
>
> Mark
>
>
> diff --git a/arch/arm/dts/rk3399-firefly.dts b/arch/arm/dts/rk3399-firefly.dts
> index be350866a7..f90e7e88db 100644
> --- a/arch/arm/dts/rk3399-firefly.dts
> +++ b/arch/arm/dts/rk3399-firefly.dts
> @@ -15,7 +15,7 @@
>
>         chosen {
>                 stdout-path = &uart2;
> -               u-boot,spl-boot-order = &sdhci, &sdmmc;
> +               u-boot,spl-boot-order = "same-as-spl", &sdhci, &sdmmc;
>         };
>
>         backlight: backlight {
> diff --git a/configs/firefly-rk3399_defconfig b/configs/firefly-rk3399_defconfig
> index 7ac4064a8b..01b3a0771f 100644
> --- a/configs/firefly-rk3399_defconfig
> +++ b/configs/firefly-rk3399_defconfig
> @@ -58,7 +58,7 @@ CONFIG_REGULATOR_RK8XX=y
>  CONFIG_PWM_ROCKCHIP=y
>  CONFIG_RAM=y
>  CONFIG_SPL_RAM=y
> -CONFIG_BAUDRATE=1500000
> +CONFIG_BAUDRATE=115200
>  CONFIG_DEBUG_UART_SHIFT=2
>  CONFIG_SYSRESET=y
>  CONFIG_USB=y