[U-Boot] [RFC 2/6] efi: add RuntimeServicesSupported variable

[Heinrich Schuchardt]

On 6/5/19 6:21 AM, AKASHI Takahiro wrote:
> This variable is defined in UEFI specification 2.8, section 8.1.
> Its value should be updated whenever we add any usable runtime services
> function.

It is also required by the EBBR specification.

>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> ---
>  include/efi_api.h            | 15 +++++++++++++++
>  include/efi_loader.h         |  3 +++
>  lib/efi_loader/efi_runtime.c | 28 ++++++++++++++++++++++++++++
>  lib/efi_loader/efi_setup.c   |  5 +++++
>  4 files changed, 51 insertions(+)
>
> diff --git a/include/efi_api.h b/include/efi_api.h
> index 65584dd2d82a..d7d95edd4dfc 100644
> --- a/include/efi_api.h
> +++ b/include/efi_api.h
> @@ -213,6 +213,21 @@ struct efi_capsule_header {
>  	u32 capsule_image_size;
>  };
>
> +#define EFI_RT_SUPPORTED_GET_TIME			0x0001
> +#define EFI_RT_SUPPORTED_SET_TIME			0x0002
> +#define EFI_RT_SUPPORTED_GET_WAKEUP_TIME		0x0004
> +#define EFI_RT_SUPPORTED_SET_WAKEUP_TIME		0x0008
> +#define EFI_RT_SUPPORTED_GET_VARIABLE			0x0010
> +#define EFI_RT_SUPPORTED_GET_NEXT_VARIABLE_NAME		0x0020
> +#define EFI_RT_SUPPORTED_SET_VARIABLE			0x0040
> +#define EFI_RT_SUPPORTED_SET_VIRTUAL_ADDRESS_MAP	0x0080
> +#define EFI_RT_SUPPORTED_CONVERT_POINTER		0x0100
> +#define EFI_RT_SUPPORTED_GET_NEXT_HIGH_MONOTONIC_COUNT	0x0200
> +#define EFI_RT_SUPPORTED_RESET_SYSTEM			0x0400
> +#define EFI_RT_SUPPORTED_UPDATE_CAPSULE			0x0800
> +#define EFI_RT_SUPPORTED_QUERY_CAPSULE_CAPABILITIES	0x1000
> +#define EFI_RT_SUPPORTED_QUERY_VARIABLE_INFO		0x2000
> +
>  struct efi_runtime_services {
>  	struct efi_table_hdr hdr;
>  	efi_status_t (EFIAPI *get_time)(struct efi_time *time,
> diff --git a/include/efi_loader.h b/include/efi_loader.h
> index 23ce73226762..7bd8002e303e 100644
> --- a/include/efi_loader.h
> +++ b/include/efi_loader.h
> @@ -573,6 +573,9 @@ static inline int guidcmp(const efi_guid_t *g1, const efi_guid_t *g2)
>  #define __efi_runtime_data __attribute__ ((section (".data.efi_runtime")))
>  #define __efi_runtime __attribute__ ((section (".text.efi_runtime")))
>
> +/* Indicate supported runtime services */
> +efi_status_t efi_init_runtime_supported(void);
> +
>  /* Update CRC32 in table header */
>  void __efi_runtime efi_update_table_header_crc32(struct efi_table_hdr *table);
>
> diff --git a/lib/efi_loader/efi_runtime.c b/lib/efi_loader/efi_runtime.c
> index 60442cb21d37..cf202bb9ec07 100644
> --- a/lib/efi_loader/efi_runtime.c
> +++ b/lib/efi_loader/efi_runtime.c
> @@ -89,6 +89,34 @@ struct elf_rela {
>   * handle a good number of runtime callbacks
>   */
>
> +efi_status_t efi_init_runtime_supported(void)
> +{
> +	u16 efi_runtime_services_supported;
> +
> +	/*
> +	 * This value must be synced with efi_runtime_detach_list
> +	 * as well as efi_runtime_services.
> +	 */
> +	efi_runtime_services_supported = EFI_RT_SUPPORTED_RESET_SYSTEM;

This support is system dependent, e.g. on RK3288 systems it does not exist.

> +#ifdef CONFIG_EFI_GET_TIME
> +	efi_runtime_services_supported |= EFI_RT_SUPPORTED_GET_TIME;

We do not support this at runtime.

> +#endif
> +#ifdef CONFIG_EFI_SET_TIME
> +	efi_runtime_services_supported |= EFI_RT_SUPPORTED_SET_TIME;

We do not support this at runtime.

> +#endif
> +#ifdef CONFIG_EFI_RUNTIME_SET_VIRTUAL_ADDRESS_MAP
> +	efi_runtime_services_supported |=
> +				EFI_RT_SUPPORTED_SET_VIRTUAL_ADDRESS_MAP;

Our support is incomplete as we have not implemented ConvertPointer().

For unsupported services we will have to change the return value to
EFI_UNSUPPORTED. But that will be a separate patch.

Best regards

Heinrich

> +#endif
> +
> +	return EFI_CALL(efi_set_variable(L"RuntimeServicesSupported",
> +					 &efi_global_variable_guid,
> +					 EFI_VARIABLE_BOOTSERVICE_ACCESS |
> +					 EFI_VARIABLE_RUNTIME_ACCESS,
> +					 sizeof(efi_runtime_services_supported),
> +					 &efi_runtime_services_supported));
> +}
> +
>  /**
>   * efi_update_table_header_crc32() - Update crc32 in table header
>   *
> diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
> index 45d6aca051f3..75fa344060d5 100644
> --- a/lib/efi_loader/efi_setup.c
> +++ b/lib/efi_loader/efi_setup.c
> @@ -123,6 +123,11 @@ efi_status_t efi_init_obj_list(void)
>  	if (ret != EFI_SUCCESS)
>  		goto out;
>
> +	/* Indicate supported runtime services */
> +	ret = efi_init_runtime_supported();
> +	if (ret != EFI_SUCCESS)
> +		goto out;
> +
>  	/* Initialize system table */
>  	ret = efi_initialize_system_table();
>  	if (ret != EFI_SUCCESS)
>