EFI Preboot Guidelines and Windows 8 UEFI Secure Boot for HP Business Notebooks and Desktops PPS Business Notebook and Desktop - Technical White Paper

Technical white paper | UEFI Secure Boot on HP business notebooks, desktops, and workstations
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法规及政策，并已获得所需的一切事先批准及许可（如适用）。若因您未获得相应的操作/使用许可而发生的
合规问题，皆由您自行承担全部责任，与惠普无涉。
确认启用TPM, 按 “+”。取消，按 “-“.
NoPPIProvision Flag in F10
The default for the NoPPIProvision flag is based on the factory setting.
TPM auto-provisioning
Windows 8 will automatically take TPM ownership to ease the deployment scenario. On an out of box setup, the OS will
automatically prepare the TPM for use. It does this by making use of the new PPI flag dUEFIned in the “PPI v1.2 PC client
Specific TPM interface” spec. The default scenario for first OS start is ”TPM is not ready for use” and the NoPPIProvision flag
is set to
True (the user will not be prompted for TPM provisioning). At this point TPM’s state is “Disabled”, “Deactivated,” and
“Not Owned.” The OS will then issue the TPM command 10 and after the first boot cycle the TPM will be “Enabled and
Activated.” Finally, after the second OS start, the TPM will be “Owned” and Windows will report that the TPM is ready for use.
If users choose not to employ this TPM auto-provisioning option, they can use the Windows Wizard to manually provision
the TPM.
POST
POST includes these tools and information:
• Drivers and firmware versions of installed software
• Information about disk drives directly attached to the chipset (not to a Smart Array Controller)
POST initializes the display in its native resolution. The logo requirements are as follows:
• Logo design:
– Centered horizontally
– 38.2% from top of screen
• Logo size:
– <
40% of screen height
– < 40% of screen width
POST time (for notebooks)
In order to minimize POST time, USB Initialization is bypassed on the default boot path. Fast boot initializes the internal HDD
only to achieve the required boot time.
POST time (for desktops and workstations)
USB initialization is not bypassed on desktops and workstations since these systems frequently have USB keyboards and
USB pointing devices.
Windows 8 Hybrid Boot and flash
By default, Hybrid Boot is enabled for Windows 8 shutdown. It is the hibernation without user data. Thus at the next boot,
the OS does a resume from S4 instead of the cold boot. However, when BIOS changes certain system configurations, either
via flash or some setting change during POST, a full restart is required for the OS to pick up the changes. In such cases, the
BIOS must inform the OS to do a full boot using the ACPI specification.
The Firmware ACPI Control Structure (FACS) table (from the ACPI specification),contains a four-byte field at offset 8 called
“Hardware Signature” with the following description:
The value of the system’s “hardware signature” at last boot is calculated by the BIOS on a best effort basis to indicate the
base hardware configuration of the system such that different base hardware configurations can have different hardware
signature values. OS-directed Power Management (OSPM) uses this information in waking from an S4 state, by comparing
the current hardware signature to the signature values saved in the nonvolatile sleep image. If the values are not the same,
OSPM assumes that the saved non-volatile image is from a different hardware configuration and cannot be restored.”