[PATCH 1/1] dm: fix blk_get_devnum_by_uclass_idname()

[Simon Glass]

Hi Heinrich,

On Mon, 3 Oct 2022 at 03:36, Heinrich Schuchardt
<heinrich.schuchardt at canonical.com> wrote:
>
> On the sandbox I run:
>
>     => setenv efi_selftest block device
>     => bootefi selftest
>
> and see the following output:
>
>     ** Bad device specification host 0 **
>     Couldn't find partition host 0:0
>     Cannot read EFI system partition
>
> Running
>
>     => lsblk
>
> yields
>
>     Block Driver          Devices
>     -----------------------------
>     efi_blk             : efiloader 0
>     ide_blk             : <none>
>     mmc_blk             : mmc 2, mmc 1, mmc 0
>     nvme-blk            : <none>
>     sandbox_host_blk    : <none>
>     scsi_blk            : <none>
>     usb_storage_blk     : <none>
>     virtio-blk          : <none>
>
> So a efi_blk device was mistaken for a host device.
>
> I continue with
>
>     => host bind 0 ../sandbox.img
>     => ls host 0:1
>
> and get the following output:
>
>            13   hello.txt
>             7   u-boot.txt
>
>     2 file(s), 0 dir(s)
>
> This is the content of efiblock 0:1 and not of host 0:1 (sic!).
>
> The uclass of the parent device is irrelevant for the determination of the
> uclass of the block device. We must use the uclass stored in the block
> device descriptor.
>
> This issue has been raised repeatedly:
>
> [PATCH 1/1] block: fix blk_get_devnum_by_typename()
> https://lore.kernel.org/u-boot/20220802094933.69170-1-heinrich.schuchardt@canonical.com/
> [PATCH 1/1] blk: simplify blk_get_devnum_by_typename()
> https://lore.kernel.org/u-boot/20211023140647.7661-1-heinrich.schuchardt@canonical.com/

Yes and you were not able/willing to take on the required work, so
this carried on longer than it should have. I finally did this myself
and it is now in -next.

So we might finally be able to fix this problem properly, since
if_type is mostly just a work-around concept in -next, with just the
fake uclass_id being used at present.

Can you use if_type_to_uclass_id() here, which is the work-around
function for now?

Also, I wonder if we can require SPL_BLK and thus get rid of the
legacy block interface? Then we can drop drop uclass_id and a few
other fields from struct blk_desc.

Regards,
Simon