sravan/system76-edk2
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

ArmVirtPkg/QemuVirtMemInfoLib: remove 1:1 mapping of top of PA range

Browse Source 
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>
This commit is contained in:
Ard Biesheuvel
2018-11-27 15:25:42 +01:00
parent 66e06a72bf
commit 364eed8479
5 changed files with 5 additions and 97 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.c
View File

@@ -21,11 +21,6 @@
// Number of Virtual Memory Map Descriptors
#define MAX_VIRTUAL_MEMORY_MAP_DESCRIPTORS 5
EFI_PHYSICAL_ADDRESS
ArmGetPhysAddrTop (
VOID
);
/**
Return the Virtual Memory Map of your platform
@@ -45,7 +40,6 @@ ArmVirtGetMemoryMap (
)
{
ARM_MEMORY_REGION_DESCRIPTOR *VirtualMemoryTable;
UINT64 TopOfMemory;
ASSERT (VirtualMemoryMap != NULL);
@@ -78,23 +72,14 @@ ArmVirtGetMemoryMap (
VirtualMemoryTable[1].Length = VirtualMemoryTable[0].PhysicalBase;
VirtualMemoryTable[1].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_DEVICE;
// Peripheral space after DRAM
TopOfMemory = MIN (1ULL << FixedPcdGet8 (PcdPrePiCpuMemorySize),
ArmGetPhysAddrTop ());
VirtualMemoryTable[2].PhysicalBase = VirtualMemoryTable[0].Length + VirtualMemoryTable[1].Length;
VirtualMemoryTable[2].VirtualBase = VirtualMemoryTable[2].PhysicalBase;
VirtualMemoryTable[2].Length = TopOfMemory -
VirtualMemoryTable[2].PhysicalBase;
VirtualMemoryTable[2].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_DEVICE;
// Remap the FD region as normal executable memory
VirtualMemoryTable[3].PhysicalBase = PcdGet64 (PcdFdBaseAddress);
VirtualMemoryTable[3].VirtualBase = VirtualMemoryTable[3].PhysicalBase;
VirtualMemoryTable[3].Length = FixedPcdGet32 (PcdFdSize);
VirtualMemoryTable[3].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK;
VirtualMemoryTable[2].PhysicalBase = PcdGet64 (PcdFdBaseAddress);
VirtualMemoryTable[2].VirtualBase = VirtualMemoryTable[2].PhysicalBase;
VirtualMemoryTable[2].Length = FixedPcdGet32 (PcdFdSize);
VirtualMemoryTable[2].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK;
// End of Table
ZeroMem (&VirtualMemoryTable[4], sizeof (ARM_MEMORY_REGION_DESCRIPTOR));
ZeroMem (&VirtualMemoryTable[3], sizeof (ARM_MEMORY_REGION_DESCRIPTOR));
*VirtualMemoryMap = VirtualMemoryTable;
}