[U-Boot] [PATCH 1/1] efi_loader: fix setting PlatformLang

[Heinrich Schuchardt]

On 4/12/19 4:49 AM, AKASHI Takahiro wrote:
> On Thu, Apr 11, 2019 at 07:23:54PM +0200, Heinrich Schuchardt wrote:
>> The UEFI variables PlatformLang and PlatformLangCodes specify the current
>> firmware language and the list of all available languages.
>>
>> Currently their values are hard coded. With the patch a new configuration
>> variable EFI_PLATFORM_LANG_CODES is provided.
>
> Generally speaking, what I expect is that we should have a single place
> where arbitrary number of UEFI variables can be configured by default.

In U-Boot the only place for configuration is Kconfig.

For most of the variables described in the UEFI spec configuration does
not make much sense. But it may be worthwhile to look at all of them and
think about an efficient way of initialization many via an array with
names, values, and attributes.

I am looking forward to your suggestions.

Best regards

Heinrich

>
>> When initializing the UEFI subsystem this configuration variable is used to
>> initialize PlatformLangCodes. The value of variable PlatformLang is read.
>> If it is not set, the first language specified in EFI_PLATFORM_LANG_CODES
>> is used to initialize PlatformLang.
>>
>> Suggested-by: Takahiro Akashi <takahiro.akashi at linaro.org>
>> Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
>> ---
>>   lib/efi_loader/Kconfig     | 10 ++++++
>>   lib/efi_loader/efi_setup.c | 70 ++++++++++++++++++++++++++++++--------
>>   2 files changed, 66 insertions(+), 14 deletions(-)
>>
>> diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
>> index a6489ca534..50b050159c 100644
>> --- a/lib/efi_loader/Kconfig
>> +++ b/lib/efi_loader/Kconfig
>> @@ -26,6 +26,16 @@ config EFI_UNICODE_CAPITALIZATION
>>   	  set, only the the correct handling of the letters of the codepage
>>   	  used by the FAT file system is ensured.
>>
>> +config EFI_PLATFORM_LANG_CODES
>> +	string "Language codes supported by firmware"
>> +	depends on EFI_LOADER
>> +	default "en-US"
>> +	help
>> +	  This value is used to initialize the PlatformLangCodes variable. Its
>> +	  value is a semicolon (;) separated list of language codes in native
>> +	  RFC 4646 format, e.g. "en-US;de-DE". The first language code is used
>> +	  to initialize the PlatformLang variable.
>> +
>>   config EFI_LOADER_BOUNCE_BUFFER
>>   	bool "EFI Applications use bounce buffers for DMA operations"
>>   	depends on EFI_LOADER && ARM64
>> diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
>> index 6e9d5fe5b7..8f0da35ba4 100644
>> --- a/lib/efi_loader/efi_setup.c
>> +++ b/lib/efi_loader/efi_setup.c
>> @@ -10,37 +10,79 @@
>>
>>   #define OBJ_LIST_NOT_INITIALIZED 1
>>
>> -/* Language code for American English according to RFC 4646 */
>> -#define EN_US L"en-US"
>> -
>>   static efi_status_t efi_obj_list_initialized = OBJ_LIST_NOT_INITIALIZED;
>>
>> -/* Initialize and populate EFI object list */
>> -efi_status_t efi_init_obj_list(void)
>> +/**
>> + * efi_init_platform_lang() - define supported languages
>> + *
>> + * Set the PlatformLangCodes and PlatformLang variables.
>> + *
>> + * Return:	status code
>> + */
>> +static efi_status_t efi_init_platform_lang(void)
>>   {
>> -	efi_status_t ret = EFI_SUCCESS;
>> +	efi_status_t ret;
>> +	efi_uintn_t data_size = 0;
>> +	char *lang = CONFIG_EFI_PLATFORM_LANG_CODES;
>> +	char *pos;
>>
>>   	/*
>> -	 * Variable PlatformLang defines the language that the machine has been
>> -	 * configured for.
>> +	 * Variable PlatformLangCodes defines the language codes that the
>> +	 * machine can support.
>>   	 */
>> -	ret = EFI_CALL(efi_set_variable(L"PlatformLang",
>> +	ret = EFI_CALL(efi_set_variable(L"PlatformLangCodes",
>>   					&efi_global_variable_guid,
>>   					EFI_VARIABLE_BOOTSERVICE_ACCESS |
>>   					EFI_VARIABLE_RUNTIME_ACCESS,
>> -					sizeof(EN_US), EN_US));
>> +					sizeof(CONFIG_EFI_PLATFORM_LANG_CODES),
>> +					CONFIG_EFI_PLATFORM_LANG_CODES));
>>   	if (ret != EFI_SUCCESS)
>>   		goto out;
>>
>>   	/*
>> -	 * Variable PlatformLangCodes defines the language codes that the
>> -	 * machine can support.
>> +	 * Variable PlatformLang defines the language that the machine has been
>> +	 * configured for.
>>   	 */
>> -	ret = EFI_CALL(efi_set_variable(L"PlatformLangCodes",
>> +	ret = EFI_CALL(efi_get_variable(L"PlatformLang",
>>   					&efi_global_variable_guid,
>> +					NULL, &data_size, &pos));
>> +	if (ret == EFI_BUFFER_TOO_SMALL) {
>> +		/* The variable is already set. Do not change it. */
>> +		ret = EFI_SUCCESS;
>> +		goto out;
>> +	}
>> +
>> +	/*
>> +	 * The list of supported languages is semicolon separated. Use the first
>> +	 * language to initialize PlatformLang.
>> +	 */
>> +	pos = strchr(lang, ';');
>> +	if (pos)
>> +		*pos = 0;
>> +
>> +	ret = EFI_CALL(efi_set_variable(L"PlatformLang",
>> +					&efi_global_variable_guid,
>> +					EFI_VARIABLE_NON_VOLATILE |
>
> Are you going to distinguish non-volatile from volatile from now on?
> FYI, I have finished a prototype code with which UEFI variables
> are managed separately from U-Boot variables (environment).
> This will allow us to implement full semantics of non-volatile
> (and authentication in the future) attribute easily.
>
>>   					EFI_VARIABLE_BOOTSERVICE_ACCESS |
>>   					EFI_VARIABLE_RUNTIME_ACCESS,
>> -					sizeof(EN_US), EN_US));
>> +					1 + strlen(lang), lang));
>> +out:
>> +	if (ret != EFI_SUCCESS)
>> +		printf("EFI: cannot initialize platform language settings\n");
>> +	return ret;
>> +}
>> +
>> +/**
>> + * efi_init_obj_list() - Initialize and populate EFI object list
>
> Well, efi_init_obj_list() is getting bigger and bigger.
> The name doesn't reflect its function precisely any more.
>
> -Takahiro Akashi
>
>
>> + * Return:	status code
>> + */
>> +efi_status_t efi_init_obj_list(void)
>> +{
>> +	efi_status_t ret = EFI_SUCCESS;
>> +
>> +	/* Define supported languages */
>> +	ret = efi_init_platform_lang();
>>   	if (ret != EFI_SUCCESS)
>>   		goto out;
>>
>> --
>> 2.20.1
>>
>