Re: Testing the recent RISC-V DT patchsets

Atish Patra
2019-05-29T07:50:18Z

On 5/28/19 8:36 AM, Karsten Merker wrote:
> On Tue, May 28, 2019 at 05:10:42PM +0200, Loys Ollivier wrote:
>> On Tue 28 May 2019 at 01:32, Paul Walmsley <paul.walmsley@sifive.com> wrote:
>>
>>> An update for those testing RISC-V patches: here's a new branch of
>>> riscv-pk/bbl that doesn't try to read or modify the DT data at all, which
>>> should be useful until U-Boot settles down.
> [...]
>>> Here is an Linux kernel branch with updated DT data that can be booted
>>> with the above bootloader:
>>>
>>> https://github.com/sifive/riscv-linux/tree/dev/paulw/dts-v5.2-rc1-experimental
>>>
>>> A sample boot log follows, using a 'defconfig' build from that branch.
>>
>> Thanks Paul, I can confirm that it works.
>>
>> Something is still unclear to myself.
>> Using FSBL + riscv-pk/bbl the linux kernel + device tree boots.
>> Neither FSBL nor riscv-pk/bbl are modifying the DT.
>>
>> Using FSBL + OpenSBI + U-Boot the same kernel + device tree hangs on
>> running /init.
>>
>> Would you have any pointer on what riscv-pk does that OpenSBI/U-boot doesn't ?
>> Or maybe it is the other way around - OpenSBI/U-boot does something that
>> extra that should not happen.
>
> Hello,
>
> I don't know which version of OpenSBI you are using, but there is
> a problem with the combination of kernel 5.2-rc1 and OpenSBI
> versions before commit
>
> https://github.com/riscv/opensbi/commit/4e2cd478208531c47343290f15b577d40c82649c
>
> that can result in a hang on executing init, so in case you
> should be using an older OpenSBI build that might be the source
> of the problem that you are experiencing.
>
> Regards,
> Karsten
>

I verified the updated DT with upstream kernel for the boot flow OpenSBI
+ U-Boot + Linux or OpenSBI + Linux.

OpenSBI should be compiled for sifive platform with following additional
argument

FW_PAYLOAD_FDT_PATH=<linux kernel
source>/arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dtb

FYI: It will only work when kernel is given a payload to U-Boot/OpenSBI
directly.

Network booting is still not working as the clock driver probe doesn't
happen because of the updated DT.

--
Regards,
Atish