Re: [PATCH] configs: layerscape: Disable the EFI_LOADER feature

[Michael Walle <michael@walle.cc>]

Am 2021-07-26 08:18, schrieb Z.Q. Hou:
> Hi Tom,
> 
>> -----Original Message-----
>> From: Tom Rini <trini@konsulko.com>
>> Sent: 2021年7月22日 23:26
>> To: Z.Q. Hou <zhiqiang.hou@nxp.com>; Michael Walle <michael@walle.cc>;
>> Heinrich Schuchardt <xypron.glpk@gmx.de>
>> Cc: u-boot@lists.denx.de; Priyanka Jain <priyanka.jain@nxp.com>
>> Subject: Re: [PATCH] configs: layerscape: Disable the EFI_LOADER 
>> feature
>> 
>> On Thu, Jul 22, 2021 at 02:25:59PM +0800, Zhiqiang Hou wrote:
>> 
>> > From: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
>> >
>> > The feature BOOTENV_SHARED_EFI is not supported on layerscape boards,
>> > it didn't result kernel boot crash previously since there isn't the
>> > efi/boot/"BOOTEFI_NAME" and it skip calling of 'boot_efi_binary'.
>> >
>> > But since the commit f3866909e350 ("distro_bootcmd: call EFI bootmgr
>> > even without having /EFI/boot"), it will cause kernel boot crash as
>> > there isn't a valid fdt_addr and it finially uses the device tree blob
>> > of U-Boot and further cause errors.
>> >
>> > As this feature is enabled by default for armv7 and armv8, so disable
>> > it explicitly to avoid calling the 'scan_dev_for_efi'.
>> 
>> I'm not thrilled with this.  Why isn't the solution to get and keep in 
>> sync the
>> device trees, so that the tree U-Boot has is valid for the kernel?  
>> I'm also
>> open to discussing f3866909e350 more.  But I'm really opposed to 
>> disabling
>> EFI_LOADER on modern platforms as that will make adoption of U-Boot in
>> device harder I feel.
>> 
> 
> I think it doesn't make sense for the platforms on which the EFI boot
> is not planed.
> As there isn't EFI boot needed components in the search path, finally
> the EFI boot
> will be skipped. I don't want to look into the EFI boot process, so I
> trend to disable
> the feature, is it acceptable?

Actually, from a customer point of view, this is really annoying. These
platforms should be reference implenention and you're skipping an
important feature, that is booting a generic linux distribution.

Anyway, I don't understand why the efi bootmgr boots on your board
at all. AFAIK it needs the BootOrder/BootNext EFI variables, no?

-michael