[U-Boot] [PATCH v2 4/5] cmd: bootefi: run an EFI application of a specific load option

[Heinrich Schuchardt <xypron.glpk@gmx.de>]

On 2/28/19 5:28 AM, AKASHI Takahiro wrote:
> On Wed, Feb 27, 2019 at 08:33:17PM +0100, Heinrich Schuchardt wrote:
>> On 2/27/19 7:47 AM, AKASHI Takahiro wrote:
>>> On Wed, Feb 27, 2019 at 07:31:06AM +0100, Heinrich Schuchardt wrote:
>>>> On 2/27/19 6:58 AM, AKASHI Takahiro wrote:
>>>>> On Tue, Feb 26, 2019 at 08:30:50PM +0100, Heinrich Schuchardt wrote:
>>>>>> On 1/15/19 3:54 AM, AKASHI Takahiro wrote:
>>>>>>> With this patch applied, we will be able to selectively execute
>>>>>>> an EFI application by specifying a load option, say "1" for Boot0001,
>>>>>>> "2" for Boot0002 and so on.
>>>>>>>
>>>>>>>   => bootefi bootmgr <fdt addr> 1, or
>>>>>>>      bootefi bootmgr - 1
>>>>>>
>>>>>> You already introduced the support for BootNext. So is there a real benefit?
>>>>>
>>>>> This is a convenient way of running EFI application directly,
>>>>> but I already removed this feature from the next version.
>>>>
>>>> Please, remove 'run -e' instead because it cannot specify the device
>>>> tree needed for booting ARM boards.
>>>
>>> See my comment for patch#5 first.
>>>
>>>>>
>>>>>>>
>>>>>>> Please note that BootXXXX need not be included in "BootOrder".
>>>>>>>
>>>>>>> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
>>>>>>> ---
>>>>>>>  cmd/bootefi.c | 39 ++++++++++++++++++++++++++++-----------
>>>>>>>  1 file changed, 28 insertions(+), 11 deletions(-)
>>>>>>>
>>>>>>> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
>>>>>>> index 3be01b49b589..241fd0f987ab 100644
>>>>>>> --- a/cmd/bootefi.c
>>>>>>> +++ b/cmd/bootefi.c
>>>>>>> @@ -471,16 +471,15 @@ static efi_status_t bootefi_test_prepare
>>>>>>>  
>>>>>>>  #endif /* CONFIG_CMD_BOOTEFI_SELFTEST */
>>>>>>>  
>>>>>>> -static int do_bootefi_bootmgr_exec(void)
>>>>>>> +static int do_bootefi_bootmgr_exec(int boot_id)
>>>>>>>  {
>>>>>>>  	struct efi_device_path *device_path, *file_path;
>>>>>>>  	void *addr;
>>>>>>>  	efi_status_t r;
>>>>>>>  
>>>>>>> -	addr = efi_bootmgr_load(EFI_BOOTMGR_DEFAULT_ORDER,
>>>>>>> -				&device_path, &file_path);
>>>>>>> +	addr = efi_bootmgr_load(boot_id, &device_path, &file_path);
>>>>>>>  	if (!addr)
>>>>>>> -		return 1;
>>>>>>> +		return CMD_RET_FAILURE;
>>>>>>>  
>>>>>>>  	printf("## Starting EFI application at %p ...\n", addr);
>>>>>>>  	r = do_bootefi_exec(addr, device_path, file_path);
>>>>>>> @@ -488,9 +487,9 @@ static int do_bootefi_bootmgr_exec(void)
>>>>>>>  	       r & ~EFI_ERROR_MASK);
>>>>>>>  
>>>>>>>  	if (r != EFI_SUCCESS)
>>>>>>> -		return 1;
>>>>>>> +		return CMD_RET_FAILURE;
>>>>>>>  
>>>>>>> -	return 0;
>>>>>>> +	return CMD_RET_SUCCESS;
>>>>>>>  }
>>>>>>>  
>>>>>>>  /* Interpreter command to boot an arbitrary EFI image from memory */
>>>>>>> @@ -546,10 +545,28 @@ static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
>>>>>>>  	} else
>>>>>>>  #endif
>>>>>>>  	if (!strcmp(argv[1], "bootmgr")) {
>>>>>>> -		if (efi_handle_fdt(argc > 2 ? argv[2] : NULL))
>>>>>>> -			return CMD_RET_FAILURE;
>>>>>>> +		char *fdtstr, *endp;
>>>>>>> +		int boot_id = EFI_BOOTMGR_DEFAULT_ORDER;
>>>>>>> +
>>>>>>> +		if (argc > 2) {
>>>>>>> +			fdtstr = argv[2];
>>>>>>> +			 /* Special address "-" means no device tree */
>>>>>>> +			if (fdtstr[0] == '-')
>>>>>>> +				fdtstr = NULL;
>>>>>>> +
>>>>>>> +			r = efi_handle_fdt(fdtstr);
>>>>>>> +			if (r)
>>>>>>> +				return CMD_RET_FAILURE;
>>>>>>> +		}
>>>>>>> +
>>>>>>> +		if (argc > 3) {
>>>>>>> +			boot_id = (int)simple_strtoul(argv[3], &endp, 0);
>>>>>>> +			if ((argv[3] + strlen(argv[3]) != endp) ||
>>>>>>> +			    boot_id > 0xffff)
>>>>>>> +				return CMD_RET_USAGE;
>>>>>>> +		}
>>>>>>>  
>>>>>>> -		return do_bootefi_bootmgr_exec();
>>>>>>> +		return do_bootefi_bootmgr_exec(boot_id);
>>>>>>
>>>>>> Why not communicate via the BootNext variable?
>>>>>
>>>>> I don't get your point.
>>>>> BootNext and BootOrder are both defined by UEFI specification.
>>>>
>>>> Instead of changing the interface of do_bootefi_bootmgr_exec()
>>>
>>> Who care changing an *internal* function?
> 
> So do you agree?

What is wrong about calling efi_set_variable(L"BootNext", ) instead?
Wouldn't that result in less code?

> 
>>>
>>>> you could
>>>> simply set BootNext. Then the boot manager would pick up the option from
>>>> the variable and finally delete the variable. This would result in less
>>>> code.
>>>
>>> No. Even with "run -e," BootNext will disappear after execution.
>>> This is a requirement by UEFI spec.
>>
>> Shouldn't BootNext always be reset when executing bootefi no matter
>> whether the boot manager is used or not?
> 
> Didn't I say the same thing?
> Or do you expect that BootNext remain after "run -e"?

As described in the response to patch 5/5 'run -e' is not usable with
ARM given the current state of device trees in Linux.

Patch 1/5 only deletes variable BootNext if the boot manager is called.
Is this really correct? Shouldn't we delete the BootNext variable when
executing `bootefi $kernel_addr_r $fdt_addr_r`, too?

Best regards

Heinrich

> 
> -Takahiro Akashi
> 
>> Regards
>>
>> Heinrich
>>
>>>
>>> Thanks,
>>> -Takahiro Akashi
>>>
>>>> Best regards
>>>>
>>>> Heinrich
>>>>
>>>>>
>>>>>>>  	} else {
>>>>>>>  		saddr = argv[1];
>>>>>>>  
>>>>>>> @@ -590,7 +607,7 @@ static char bootefi_help_text[] =
>>>>>>>  	"    Use environment variable efi_selftest to select a single test.\n"
>>>>>>>  	"    Use 'setenv efi_selftest list' to enumerate all tests.\n"
>>>>>>>  #endif
>>>>>>> -	"bootefi bootmgr [fdt addr]\n"
>>>>>>> +	"bootefi bootmgr [<fdt addr>|'-' [<boot id>]]\n"
>>>>>>>  	"  - load and boot EFI payload based on BootOrder/BootXXXX variables.\n"
>>>>>>>  	"\n"
>>>>>>>  	"    If specified, the device tree located at <fdt address> gets\n"
>>>>>>> @@ -598,7 +615,7 @@ static char bootefi_help_text[] =
>>>>>>>  #endif
>>>>>>>  
>>>>>>>  U_BOOT_CMD(
>>>>>>> -	bootefi, 3, 0, do_bootefi,
>>>>>>> +	bootefi, 5, 0, do_bootefi,
>>>>>>
>>>>>> Why 5?
>>>>>
>>>>> For additional/optional '-' and <boot id>.
>>>>> But I removed this feature from bootefi.
>>>>>
>>>>> Thanks,
>>>>> -Takahiro Akashi
>>>>>
>>>>>
>>>>>> Best regards
>>>>>>
>>>>>> Heinrich
>>>>>>
>>>>>>>  	"Boots an EFI payload from memory",
>>>>>>>  	bootefi_help_text
>>>>>>>  );
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>