We are pleased to announce that the FSP External Architecture Specification v2.1 has been
posted to https://www.intel.com/fsp
* Dispatch Mode – A new optional FSP boot mode intended to ease integration of FSP
with PI spec bootloaders. In dispatch mode, FSP-M and FSP-S are containers that expose
firmware volumes (FVs) directly to the bootloader. The PEIMs in these FVs are executed
directly in the context of the PEI environment provided by the bootloader. In dispatch
mode, the FspMemoryInit(), FspSiliconInit(), and NotifyPhase() API’s are not used.
NotifyPhase() is replaced by FSP-S containing DXE drivers that provide a native
implementation of equivalent events for each of the NotifyPhase() invocations.
Dispatch mode is entirely optional. FSP 2.1 is fully backwards compatible with FSP 2.0,
all of the APIs still work the same way. We have no plans to change that. While dispatch
mode is the biggest new feature, it is also largely not relevant for Slim Bootloader.
* More Robust Error Reporting – The current FSP 2.0 just returns an EFI_STATUS code
without any context. If that status code is anything other than EFI_SUCCESS, FSP 2.0 gives
very little visibility in to what specifically may be going wrong. FSP 2.1 adds the
FSP_ERROR_INFO_HOB, which provides more granularity on FSP error data and will aid in the
debug of error codes returned by FSP.
* Improved Graphics Support – Starting with FSP 2.1, in addition to the
EFI_PEI_GRAPHICS_INFO_HOB, FSP will now also produce the EFI_PEI_GRAPHICS_DEVICE_INFO_HOB.
This enables the implementation of a generic graphics driver.
* Improved Memory Utilization – FspMemoryInit() will now run on top of the existing
bootloader stack instead of establishing it own stack. his allows the stack memory to be
reused after FspMemoryInit() returns to the bootloader. After FspMemoryInit(), large
amounts of DRAM will be available. So FSP will split its stack and global data at this
point, since the memory pressure is gone.
AmberLakeFspBinPkg has been released on https://github.com/IntelFsp/FSP
, which provides
the first implementation of FSP 2.1. This FSP is backward compatible with Kaby Lake, so
there should be a good amount of existing hardware available for those who are interested
in trying FSP 2.1. Looking forward, our upcoming Ice Lake and Comet Lake platforms will
have FSP 2.1 binaries once they are released.
Does Anything Need to Change in Slim Bootloader?
For the most part no. There are some new header structure definitions to bring in.
Optionally, Slim Bootloader can now report any data provided by FSP_ERROR_INFO_HOB and a
generic graphics driver can now be written leveraging EFI_PEI_GRAPHICS_DEVICE_INFO_HOB.