[PATCH 02/10] efi_loader: add option to initialise EFI subsystem early

[Heinrich Schuchardt]

On 4/28/20 2:16 AM, AKASHI Takahiro wrote:
> Heinrich,
>
> On Mon, Apr 27, 2020 at 10:09:11PM +0200, Heinrich Schuchardt wrote:
>> On 4/27/20 11:48 AM, AKASHI Takahiro wrote:
>>> If this option is enabled, the initialisation of UEFI subsystem will be
>>> done as part of U-Boot initialisation.
>>>
>>> This feature will be utilised in implementing capsule-on-disk feature.
>>
>> This would mean that we allow unaligned access very early. Something
>> Siarhei was against:
>
> ?
> Even with CONFIG_EFI_CAPSULE_ON_DISK_EARLY enabled,
> efi_init_obj_list() is called at the last of "init" list
> and efi_launch_capsules() is called just before the main
> command loop.
> So "unalignment" issue won't happen.

efi_init_obj_list() is even called when booting via booti and therefore
before a lot of other code.

Best regards

Heinrich

>
>> https://lists.denx.de/pipermail/u-boot/2018-March/324242.html
>> https://patchwork.ozlabs.org/project/uboot/patch/20180329213350.7868-1-xypron.glpk@gmx.de/
>>
>> Why can't you wait with the capsule update until any command initializes
>> the UEFI sub-system.
>
> This topic is the one the I mentioned in RFC's cover letter
> and asked you for comments several time.
> Anyway, there are a couple of reasons:
> 1. Updated firmware may have some effects on not only UEFI
>    subsystem but also U-Boot's other features.
> 2. Firmware update should surely take place after reboot
>    as UEFI specification expects.
> 3. Firmware update should not rely on user's interactions
>    or whatever "bootcmd" is set to.
> 4. In case of failure of firmware update, some recovery should
>    be automatically taken "before" the command line is handed over
>    to users. (The feature is not implemented yet though.)
>
> -Takahiro Akashi
>
>
>> Best regards
>>
>> Heinrich
>>
>>>
>>> Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
>>> ---
>>>  common/board_r.c       | 6 ++++++
>>>  lib/efi_loader/Kconfig | 4 ++++
>>>  2 files changed, 10 insertions(+)
>>>
>>> diff --git a/common/board_r.c b/common/board_r.c
>>> index 0bbeaa7594c6..7cf21a6078f9 100644
>>> --- a/common/board_r.c
>>> +++ b/common/board_r.c
>>> @@ -64,6 +64,9 @@
>>>  #if defined(CONFIG_GPIO_HOG)
>>>  #include <asm/gpio.h>
>>>  #endif
>>> +#ifdef CONFIG_EFI_SETUP_EARLY
>>> +#include <efi_loader.h>
>>> +#endif
>>>
>>>  DECLARE_GLOBAL_DATA_PTR;
>>>
>>> @@ -867,6 +870,9 @@ static init_fnc_t init_sequence_r[] = {
>>>  #endif
>>>  #if defined(CONFIG_M68K) && defined(CONFIG_BLOCK_CACHE)
>>>  	blkcache_init,
>>> +#endif
>>> +#ifdef CONFIG_EFI_SETUP_EARLY
>>> +	(init_fnc_t)efi_init_obj_list,
>>>  #endif
>>>  	run_main_loop,
>>>  };
>>> diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
>>> index 1cfa24ffcf72..7cc2d940f848 100644
>>> --- a/lib/efi_loader/Kconfig
>>> +++ b/lib/efi_loader/Kconfig
>>> @@ -25,6 +25,10 @@ config EFI_LOADER
>>>
>>>  if EFI_LOADER
>>>
>>> +config EFI_SETUP_EARLY
>>> +	bool
>>> +	default n
>>> +
>>>  config EFI_GET_TIME
>>>  	bool "GetTime() runtime service"
>>>  	depends on DM_RTC
>>>
>>