Re: [PATCH v6 10/20] LoongArch: Boot Image bits

[Yao Zi <me@ziyao.cc>]

On Sat, Oct 31, 2026 at 01:43:27AM -0700, Simon Glass wrote:
> Hi Jiaxun,
> 
> On 2026-10-29T05:07:18+11:00, Yao Zi <me@ziyao.cc> wrote:
> > LoongArch: Boot Image bits
> >
> > Implement loading and booting functions for LoongArch
> > standard kernel image as per spec.
> >
> > LoongArch kernel do expect us to fake a efi systemtable
> > for passing fdt to kernel, we don't need to implement any
> > EFI functions for kernel because it won't look into anything
> > beside devicetree from that table if we tell kernel we are
> > not efi compatible by setting a0 boot argument to zero.
> >
> > Link: https://docs.kernel.org/arch/loongarch/booting.html
> > Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
> > Signed-off-by: Yao Zi <me@ziyao.cc>
> >
> >  arch/loongarch/lib/Makefile |   2 +
> >  arch/loongarch/lib/bootm.c  | 129 ++++++++++++++++++++++++++++++++++++++++++++
> >  arch/loongarch/lib/image.c  |  77 ++++++++++++++++++++++++++
> >  boot/Kconfig                |   1 +
> >  cmd/Kconfig                 |   2 +-
> >  5 files changed, 210 insertions(+), 1 deletion(-)
> 
> > diff --git a/arch/loongarch/lib/bootm.c b/arch/loongarch/lib/bootm.c
> > @@ -0,0 +1,129 @@
> > +	systab->hdr.crc32 = crc32(0, (const unsigned char *)systab,
> > +				  systab->hdr.headersize);
> > +
> > +	cfgtab[0].guid = efi_guid_fdt;
> > +	cfgtab[0].table = images->ft_addr;
> > +
> > +	gd->bd->bi_boot_params = (ulong)systab;
> 
> The CRC is still calculated before cfgtab[0] is filled in, so please
> move it after that.

Oops, I'm totally confused by UEFI specification, where hdr.headersize
is the size of the full table, instead of only the header's size :(

I'll fix it up.

> Also please use map_to_sysmem(systab) for
> bi_boot_params rather than a plain cast.

The problem is that bi_boot_params is ulong, not a pointer, I don't
think it improves anything here?

> > diff --git a/arch/loongarch/lib/image.c b/arch/loongarch/lib/image.c
> > @@ -0,0 +1,77 @@
> > +	uint32_t	code0;			/* Executable code */
> > +	uint32_t	code1;			/* Executable code */
> > +	uint64_t	kernel_entry;		/* Kernel entry point */
> 
> Please can you use u32/u64 for these members?

Sure.

> In any case:
> Reviewed-by: Simon Glass <sjg@chromium.org>
> 
> Regards,
> Simon

Best regards,
Yao Zi