Currently, we map DRAM as EFI_MEMORY_WB, and the remainder of the
entire virtual address space is mapped with EFI_MEMORY_UC attributes,
regardless of whether any devices actually reside there.
Now that we are relaxing the address space limit to more than 40 bits,
mapping all that address space actually takes up more space in page
tables than we have so far made available as temporary RAM. So let's
get rid of the mapping rather than increasing the available RAM, given
that the mapping is not particularly useful anyway.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
The QemuVirtMemInfoLib ArmVirtMemInfoLib implementation created for
ArmVirtQemuKernel does exactly what we need for ArmVirtQemu, the only
difference being that the latter is PrePeiCore based, and so it uses
a different method to ensure that PcdSystemMemorySize is set when
ArmVirtGetMemoryMap() is called.
On ArmVirtQemu, we currently abuse the implied ordering guarantees
provided by ArmPlatformLib, by implementing this as follows:
ArmPlatformPkg/MemoryInitPei/MemoryInitPeim.inf [ArmVirtPkg/ArmVirtQemu.dsc]
InitializeMemory() [ArmPlatformPkg/MemoryInitPei/MemoryInitPeim.c]
ArmPlatformInitializeSystemMemory() [ArmVirtPkg/Library/ArmVirtPlatformLib/Virt.c]
//
// set PcdSystemMemorySize from the DT
//
MemoryPeim() [ArmVirtPkg/Library/ArmVirtMemoryInitPeiLib/ArmVirtMemoryInitPeiLib.c]
InitMmu() [ArmVirtPkg/Library/ArmVirtMemoryInitPeiLib/ArmVirtMemoryInitPeiLib.c]
ArmPlatformGetVirtualMemoryMap() [ArmVirtPkg/Library/ArmVirtPlatformLib/VirtMem.c]
//
// consume PcdSystemMemorySize
//
Given that we are trying to get rid of ArmPlatformLib, or at least remove
some of these API functions that are never used for their original purpose
by any platforms, we need to move the PCD assignment elsewhere.
So create a PEIM-only version of QemuVirtMemInfoLib especially for
ArmVirtQemu, and add the PCD assignment code to its constructor.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Create a new ArmVirtMemInfoLib for ArmVirtQemuKernel by cloning the
existing ArmPlatformGetVirtualMemoryMap () for this platform,
(ArmQemuRelocatablePlatformLib *not* ArmVirtPlatformLib), and cleaning
it up:
- remove support for uncached DRAM mappings
- replace EFI_D_xxx with DEBUG_xxx throughout
- use a temp variable to hold the top of the physical address space
- use AllocatePool () instead of AllocatePages (), given that we use
160 bytes only, and the memory is never freed.
In a future patch, we will add this library to the ordinary ArmVirtQemu
platform as well.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Ard Biesheuvel