[PATCH v5 4/7] efi_loader: support boot from URI device path

[Masahisa Kojima]

Hi Ilias,

On Fri, 29 Sept 2023 at 20:48, Ilias Apalodimas
<ilias.apalodimas at linaro.org> wrote:
>
> Hi Kojima-san,
>
>
> [...]
>
> > +
> > +/**
> > + * try_load_default_file() - try to load the default file
> > + *
> > + * Search the device having EFI_SIMPLE_FILE_SYSTEM_PROTOCOL,
> > + * then try to load with the default boot file(e.g. EFI/BOOT/BOOTAA64.EFI).
> > + *
> > + * @dev                      pointer to the UCLASS_BLK or UCLASS_PARTITION udevice
> > + * @image_handle:    pointer to handle for newly installed image
> > + * Return:           status code
> > + */
> > +static efi_status_t try_load_default_file(struct udevice *dev,
> > +                                       efi_handle_t *image_handle)
> > +{
> > +     efi_status_t ret;
> > +     efi_handle_t handle;
> > +     struct efi_handler *handler;
> > +     struct efi_device_path *file_path;
> > +     struct efi_device_path *device_path;
> > +
> > +     if (dev_tag_get_ptr(dev, DM_TAG_EFI, (void **)&handle)) {
> > +             log_warning("DM_TAG_EFI not found\n");
> > +             return EFI_INVALID_PARAMETER;
> > +     }
> > +
> > +     ret = efi_search_protocol(handle,
> > +                               &efi_simple_file_system_protocol_guid, &handler);
> > +     if (ret != EFI_SUCCESS)
> > +             return ret;
> > +
> > +     ret = EFI_CALL(bs->open_protocol(handle, &efi_guid_device_path,
> > +                                      (void **)&device_path, efi_root, NULL,
> > +                                      EFI_OPEN_PROTOCOL_GET_PROTOCOL));
> > +     if (ret != EFI_SUCCESS)
> > +             return ret;
> > +
> > +     file_path = expand_media_path(device_path);
> > +     ret = EFI_CALL(efi_load_image(true, efi_root, file_path, NULL, 0,
> > +                                   image_handle));
> > +
> > +     efi_free_pool(file_path);
> > +
> > +     return ret;
> > +}
>
> We've discussed this on v4, but I am replying here, since you sent a v5 in
> the meantime.
> What I ideally wanted to do here is
> - Add the boot option automatically once the disk gets mount (you've
> already sent a patch for that)
> - Since the boot option is automatically added we could instead of
>   searching for BOOTAA64.EFI search for matches with a load option of
>   '1234567'.
> Is there some timing issue that I am missing which doesnt allow us to do
> that ?

Sorry, I probably misunderstood your design.
What kind of boot option is automatically added when the disk is detected?
Could you share your thoughts about the trigger to search for matches
with a load option of '1234567'?

Thanks,
Masahisa Kojima

>
> [...]
>
> Cheers
> /Ilias