[U-Boot] flashing and testing u-boot on chromebook_bob

Sahaj Sarup sahajsarup at gmail.com
Sat Nov 30 05:24:02 UTC 2019


Hi Simon,

Been a couple of weeks. I have obtained a SuzyQable and its working
well with bob. I can see RxTx from Cr50, AP and EC. On mainline linux
from ArchLinuxArm I can see earlyprintk as well. However I am still
stuck on the u-boot end.

Just to make sure I didn't miss anything, I'm laying down all the
steps that I followed to have u-boot chainloaded from depthcharge on
bob.

1. Build U-boot
- Build bl31 as in README.rockchip. export bl31.elf as BL31 env
- change CONFIG_SYS_TEXT_BASE to 0x20000100
    - 0x20000000 From
https://chromium.googlesource.com/chromiumos/platform/depthcharge/+/refs/heads/master/board/bob/defconfig#11
    - 0x100 padding for fit image.
- make chromebook_bob_defconfig
- make

2. Create Fit Image (some hints taken from
https://wiki.debian.org/InstallingDebianOn/Asus/C101PA)
- Using the following .its
```
/dts-v1/;

/ {
    description = "U-Boot + FDT -------- THIS PADDING IS NEEDED SO THE
IMAGE STARTS AT THE RIGHT OFFSET";
    #address-cells = <1>;

    images {

        kernel at 1 {
            description = "kernel";
            data = /incbin/("../../u-boot.bin");
            type = "kernel_noload";
            os = "linux";
            arch = "arm64";
            compression = "none";
            load = <0>;
            entry = <0>;
        };
        fdt at 1 {
            description = "rk3399-gru-bob.dtb";
            data = /incbin/("../../arch/arm/dts/rk3399-gru-bob.dtb");
            type = "flat_dt";
            arch = "arm64";
            compression = "none";
            hash at 1 {
                                algo = "sha1";
                        };
        };

    };
    configurations {
        default = "conf at 1";
        conf at 1 {
            kernel = "kernel at 1";
            fdt = "fdt at 1";
        };

    };

};
```

- mkimage -D "-I dts -O dtb -p 2048" -f
doc/chromium/chromebook_bob.its ./u-boot-chromium.fit

- Made sure that the offset is 0x100

```
[sahaj at fedora-work u-boot]$ hexdump u-boot.bin | head
0000000 000a 1400 201f d503 0100 2000 0000 0000

[sahaj at fedora-work u-boot]$ hexdump u-boot-chromium.fit | head -20
<truncated>
00000e0 0000 0300 0000 0700 0000 0000 656b 6e72
00000f0 6c65 0000 0000 0300 0b00 842c 0000 1b00
0000100 000a 1400 201f d503 0100 2000 0000 0000
0000110 33f8 000a 0000 0000 33f8 000a 0000 0000
0000120 0a18 000c 0000 0000 003c 1400 76a0 1000
0000130 4241 d538 303f f100 00a0 5400 203f f100
[sahaj at fedora-work u-boot]$
```

- Created bootloader offset: dd if=/dev/zero of=bootloader.bin bs=512 count=1

- Build image: vbutil_kernel --pack u-boot.kpart --version 1 --vmlinuz
u-boot-chromium.fit --arch aarch64 --keyblock
doc/chromium/devkeys/kernel.keyblock --signprivate
doc/chromium/devkeys/kernel_data_key.vbprivk --config dummy.txt
--bootloader bootloader.bin


3. Flash and boot:

- SDCard kernel part: cgpt add -i 1 -t kernel -b 8192 -s 65536 -l
Kernel -S 1 -T 5 -P 10 /dev/sda
- sudo dd if=u-boot.kpart of=/dev/sdd1
- On the dev mode screen select ctrl+u
- ttyUSB1 (AP COnsole) remains blank
- power led is solid
- keep power button pressed for 10 sec for poweroff



On Fri, 22 Nov 2019 at 03:53, Simon Glass <sjg at chromium.org> wrote:
>
> +U-Boot Mailing List
> Please do copy the mailing list on each message.
>
> On Wed, 20 Nov 2019 at 17:16, Sahaj Sarup <sahajsarup at gmail.com> wrote:
> >
> >
> >
> > On Tue, Nov 19, 2019, 06:51 Simon Glass <sjg at chromium.org> wrote:
> >>
> >> Hi Sahaj,
> >>
> >> On Mon, 18 Nov 2019 at 00:09, Sahaj Sarup <sahajsarup at gmail.com> wrote:
> >> >
> >> > see in-line...
> >> >
> >> > On Mon, 18 Nov 2019 at 11:16, Simon Glass <sjg at chromium.org> wrote:
> >> > >
> >> > > Hi Sahaj,
> >> > >
> >> > > On Sun, 17 Nov 2019 at 21:33, Sahaj Sarup <sahajsarup at gmail.com> wrote:
> >> > > >
> >> > > > Hi All,
> >> > > >
> >> > > > I was wondering if you could answer a few questions regarding u-boot
> >> > > > on Asus CP101 gru/bob ?
> >> > > >
> >> > > > - To test the u-boot image following README.chromium-chainload,
> >> > > > should I expect output on the display or do I need
> >> > > > CDD/SuzyQable Cable for serial?
> >> > >
> >> > > The display should work OK. I don't think that device supports CCD.
> >> >
> >> > Well since the display is blank and the uboot.bin and uboot.fit have
> >> > a correct 0x100 offset, I'll need to wait for my CCD cable to arrive.
> >> > Bob in fact supports ccd:
> >> > https://www.chromium.org/chromium-os/developer-information-for-chrome-os-devices
> >> > Although, i am confused as well since edp is supported, at least in
> >> > the dts files.
> >>
> >> Then I suspect it is broken.
> >
> >
> > Not broken, doesn't exist. The Edp driver is only for rk3288. I'm guessing they use the same ip, but soc specific stuff needs to be added for 3399.
> >
> > I was taking a look at rockchip's u-boot fork, looks like they are using drm for display now.
>
> OK I see,
>
> Regards,
> Simon



-- 
Best Regards
Sahaj Sarup


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