SGX Registration Status

This variable is created by BIOS and is always available to software for reading on all boot flows (including when SGX is disabled). When BIOS needs to communicate to the software that some action needs to take place, BIOS resets one of the defined Status bits to 0. When software completes the action, it can set the relevant status bit to 1 to prevent BIOS from requesting the same action on a subsequent boot and to limit exposure of privacy sensitive data. When all valid status bits are set to 1, BIOS makes this variable read-only. Software can also use this variable to query the status of an action on future boot flows, so the status bits need to be preserved by BIOS across boots (until a new action is required). If one of the status bits remains 0 on a subsequent boot, BIOS provides the data necessary to allow the software to retry that action.

BIOS communicates to software any errors that occurred during a boot flow by setting the Error Code to a non-zero value (with the most significant bit reset to 0). If BIOS reports an error, there is no action for software to take. Software can also write to the Error Code when it encounters an error (with the most significant bit set to 1). To allow a software Error Code to persist across boot flows, BIOS should not overwrite a non-zero software ErrorCode on a subsequent successful normal boot flow.

Table 1: SgxRegistrationStatus

GUID	f236c5dc-a491-4bbe-bcdd-88885770df45
Size	2
Attributes	Read-Write then Read-only.
Description	BIOS creates this variable whenever communication to the registration authority service is required or whenever a key blob backup is required.
Fields	See table SgxRegistrationStatus Fields

Table 2: SgxRegistrationStatus Fields

Name	Size	Type	Description
Version	2	LE Integer	1
Size	2	LE Integer	Size in bytes of data below
Status	2	Little Endian	BIT[0]: SgxRegistrationComplete     0: SGX Registration is in progress.     SgxRegistrationServerRequest is accessible.     1: SGX Registration is complete.     SGXRegistrationResponse is available when ErrorCode is 0.     SgxPlatformServerRequest is not accessible on next boot. BIT[1]: SgxRegistrationPackageInfo read complete     0: RegistrationPackageInfo backup in process.     SgxRegistrationPackageInfo accessible.     1: RegistrationPackageInfo backup is complete.     SgxRegistrationPackageInfo is not accessible on next boot. BIT[15:2]: Reserved
Error Code	1	N/A	Registration Error Code. BIOS errors have most significant bit reset. SW errors have most significant bit set.