Re: Grub doesn’t load devicetree

[Simon Glass]

Hi Tomaž,

On Thu, 29 Aug 2024 at 03:44, Peter Robinson <pbrobinson at gmail.com> wrote:
>
> On Thu, 29 Aug 2024 at 10:40, Tomaž Zaman <tomaz at mono.si> wrote:
>
> > I get this:
> >
> > No UEFI binary known at 0x81000000
> >

That is the UEFI hack which we need to clean up at some point.

When you load an image, it calls efi_set_bootdev() so EFI knows where
it came from. You could check that the call is happening in your case.

Can U-Boot use the same DT as Linux?

>
> Are you building the kernel with all the appropriate UEFI shim bits?
> Installing the EFI kernel pieces etc?
>
> Sorry, I can't help with kernel build process bits, you'll need to google
> that.
>
>
> > *Tomaž Zaman, *CEO
> > Mono Technologies Inc.
> > +386 30 651 645
> >
> >
> >
> > On 29 Aug 2024 at 11:38 +0200, Peter Robinson <pbrobinson at gmail.com>,
> > wrote:
> >
> >
> >
> > On Thu, 29 Aug 2024 at 10:31, Tomaž Zaman <tomaz at mono.si> wrote:
> >
> >> Doesn’t work - at least not correctly:
> >>
> >> => fatload mmc 0:1 $fdt_addr_r /boot/dtb/fsl-ls1046a-rdb-sdk.dtb
> >> 31793 bytes read in 4 ms (7.6 MiB/s)
> >> => fatload mmc 0:1 $kernel_addr_r /EFI/boot/grubaa64.efi
> >> 3978688 bytes read in 168 ms (22.6 MiB/s)
> >> => setenv fman_ucode
> >> => bootefi $kernel_addr_r $fdt_addr_r
> >> Failed to load EFI variables
> >> WARNING failed to get smmu node: FDT_ERR_NOTFOUND
> >> WARNING failed to get smmu node: FDT_ERR_NOTFOUND
> >> Booting /\EFI\boot\grubaa64.efi
> >> Welcome to GRUB!
> >>
> >> Because of those FDT_ERR_NOTFOUND kernel reports a bunch of errors and
> >> doesn’t boot with all the hardware support I need it to.
> >>
> >> On the other hand, if I run the same kernel/devicetree/initramfs with
> >> booti, bypassing the Grub completely, it works fine. The problem is, I need
> >> Grub2 for his project.
> >>
> >
> > What if you boot the kernel directly using bootefi rather than booti?
> >
> >
> >> *Tomaž Zaman, *CEO
> >> Mono Technologies Inc.
> >> +386 30 651 645
> >>
> >>
> >>
> >> On 29 Aug 2024 at 10:02 +0200, Peter Robinson <pbrobinson at gmail.com>,
> >> wrote:
> >>
> >> On Thu, 29 Aug 2024 at 05:14, Tomaž Zaman <tomaz at mono.si> wrote:
> >>
> >>
> >> I’m working on an arm64 board with an NXP LS1046A CPU and I simply cannot
> >> get Grub to load a different device tree than the one that’s provided to it
> >> by the EFI Stub.
> >>
> >> => fatload mmc 0:1 $kernel_addr_r /EFI/boot/grubaa64.efi
> >> => fatload mmc 0:1 $fdt_addr_r /boot/dtb/fsl-ls1046a-rdb-sdk.dtb
> >> => bootefi $kernel_addr_r $fdt_addr_r
> >>
> >> At his point, I get a couple of errors like “smmu node not found”.
> >>
> >> However, if I, instead of "fsl-ls1046a-rdb-sdk.dtb” use
> >> "fsl-ls1046a-rdb.dtb”, then I get to Grub without any errors.
> >>
> >> And this is where I encounter the issue. Because I would like to use a
> >> different DTB for booting Linux than the one that’s provided by the EFI
> >> configuration table, I set
> >>
> >> devicetree /boot/dtb/fsl-ls1046a-rdb-sdk.dtb
> >> linux /boot/vmlinuz-6.6.3-arm64
> >> initrd /boot/initrd.img-6.6.3-arm64
> >>
> >> In this case, the devicetree instruction gets ignored completely, and
> >> before I see kernel loading, the message “Using FDT from the EFI
> >> configuration table"
> >>
> >> Is there a way for me to override/replace the device tree that u-boot
> >> passed to Grub? I tried passing the “dtb=“ parameter to the kernel boot
> >> command, but in that case, I get "EFI stub: ERROR: Failed to handle
> >> fs_proto” because kernel when booting doesn’t appear to have access to the
> >> same filesystem that Grub does.
> >>
> >>
> >> Why don't you load a new one into memory with u-boot and then grub
> >> will already have the one you want to use and grun doesn't need to do
> >> anything. Something like this on the U-Boot command line would load
> >> the DT and grub and start to boot:
> >>
> >> load mmc 0:1 ${kernel_addr_r} EFI/BOOT/BOOTAA64.EFI
> >> load mmc 0:1 ${fdt_addr_r} dtb/${fdtfile}
> >> bootefi ${kernel_addr_r} ${fdt_addr_r}
> >>
> >> You'll need to adjust for storage, partitions, file paths etc.
> >>
> >> Thank you!
> >>
> >>
> >> (this is my first time using *any* mailing list, so apologies if this is
> >> the wrong address to send this question to)
> >>
> >> Tomaž Zaman, CEO
> >> Mono Technologies Inc.
> >> +386 30 651 645
> >>
> >> [cid:18EB2FEE485A4DD7A1CE716CE14FCBC7]
> >>
> >>

Regards,
Simon