Our poor man's implementation of EnterS3WithImmediateWake () currently
sets a high TPL level to disable interrupts, and simply calls the
PEI entrypoint again after disabling the MMU.
Unfortunately, this is not sufficient: DMA capable devices such as
network controllers or USB controllers may still be enabled and
writing to memory, e.g., in response to incoming network packets.
So instead, do the full ExitBootServices() dance: allocate space and
get the memory map, call ExitBootServices(), and in case it fails, get
the memory map again and call ExitBootServices() again. This ensures
that all cleanup related to DMA capable devices is performed before
doing the warm reset.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Implement ResetSystemLib's EnterS3WithImmediateWake() routine using
a jump back to the PEI entry point with interrupts and MMU+caches
disabled. This is only possible at boot time, when we are sure that
the current CPU is the only one up and running. Also, it depends on
the platform whether the PEI code is preserved in memory (it may be
copied to DRAM rather than execute in place), so also add a feature
PCD to selectively enable this feature.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
This adds an implementation of the ResetSystemLib library class as
defined in MdeModulePkg. It is used as the platform glue by the generic
ResetSystemRuntimeDxe which lives in the same package.
This implementation is intended to replace the EfiResetSystemLib based
implementation that is deprecated now that we have decided that there is
no longer a reason to keep a different ResetSystem() implementation
under EmbeddedPkg.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Ard Biesheuvel