Re: [PATCH V11 09/22] LoongArch: Add boot and setup routines

[Huacai Chen]

Hi, Ruoyao,

On Tue, May 24, 2022 at 4:27 PM Xi Ruoyao <xry111@xxxxxxxxxxx> wrote:
>
> On Wed, 2022-05-18 at 17:26 +0800, Huacai Chen wrote:
> > Currently an existing interface between the kernel and the bootloader
> > is  implemented. Kernel gets 2 values from the bootloader, passed in
> > registers a0 and a1; a0 is an "EFI boot flag" distinguishing UEFI and
> > non-UEFI firmware, while a1 is a pointer to an FDT with systable,
> > memmap, cmdline and initrd information.
>
> If I understand this correctly, we can:
>
> - set a0 to 0
> - set a1 a pointer (virtual address or physical address?) to the FDT
> with these information
>
> in the bootloader before invoking the kernel, then it will be possible
> to boot this kernel w/o firmware update?
Unfortunately, there is no released firmware for you since we recently
changed the interface again and again. :(
You can contact with Li Chao (lichao@xxxxxxxxxxx), I think he can
provide help as much as possible (at least provide temporary firmwares
for developers).
We will also provide qemu-system and virtual machine's firmware as
soon as possible.

Huacai

>
> I'd prefer to receive a firmware update anyway, but we need an
> alternative if some vendor just say "no way, our customized distro works
> fine and you should use it".  (I'm not accusing LoongArch: such annoying
> behavior is common among vendors of all architectures, and even worse
> with x86 because they often say "just use Windoge".)
> --
> Xi Ruoyao <xry111@xxxxxxxxxxx>
> School of Aerospace Science and Technology, Xidian University