ArmPkg Runtime - jljusten/tianocore GitHub Wiki

Table of Contents

How to write a UEFI Runtime driver

Implementation Rules

  • Ensure your driver has been declared with 'MODULE_TYPE = DXE_RUNTIME_DRIVER' in its INF file.
That would load the code and data sections into UEFI memory regions marked as 'Runtime' regions (EfiRuntimeServicesCode and EfiRuntimeServicesData)
  • Allocate all the persistent data into runtime space (ie: use AllocateRuntimePool() instead of AllocatePool())
  • Do not allocate memory in code called after ExitBootServices().
  • Do not access BootServices API during Runtime mode - or protect the code:
  if (!EfiAtRuntime ()) {
    // Raise TPL to TPL_HIGH to stop anyone from interrupting us.
    OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
  }
  • Declare the controller memory region as Runtime Memory Mapped IO:
  Status = gDS->SetMemorySpaceAttributes (mControllerRegionBase, mControllerRegionSize, EFI_MEMORY_UC | EFI_MEMORY_RUNTIME);
  ASSERT_EFI_ERROR (Status);
  • Do not hardcode base addresses in code called after ExitBootServices(). These addresses might need to be fixed up in Operating System Virtual Memory view.
  • Fixup all the controller and dynamic addresses invoked during Runtime mode. Example:
VOID
EFIAPI
MyDriverVirtualNotifyEvent (
  IN EFI_EVENT        Event,
  IN VOID             *Context
  )
{
  EfiConvertPointer (0x0, (VOID**)&mMyControllerBase);

  // Convert allocated buffer
  EfiConvertPointer (0x0, (VOID**)&mMyDriverInstance->Buffer);

  // Convert BlockIo protocol
  EfiConvertPointer (0x0, (VOID**)&mMyDriverInstance->BlockIoProtocol.FlushBlocks);
  EfiConvertPointer (0x0, (VOID**)&mMyDriverInstance->BlockIoProtocol.ReadBlocks);
  EfiConvertPointer (0x0, (VOID**)&mMyDriverInstance->BlockIoProtocol.Reset);
  EfiConvertPointer (0x0, (VOID**)&mMyDriverInstance->BlockIoProtocol.WriteBlocks);

  return;
}

DriverEntryPoint () {
  (...)
  mMyDriverInstance->Buffer = AllocateRuntimePool (BUFFER_SIZE);

  //
  // Register for the virtual address change event
  //
  Status = gBS->CreateEventEx (
                  EVT_NOTIFY_SIGNAL,
                  TPL_NOTIFY,
                  MyDriverVirtualNotifyEvent,
                  NULL,
                  &gEfiEventVirtualAddressChangeGuid,
                  &mMyDriverVirtualAddrChangeEvent
                  );
  ASSERT_EFI_ERROR (Status);

  (...)
}

Validation

UEFI Shell

Confirm the runtime regions are present by using the command 'memmap' in the EFI Shell.

Note: The attribute '8000000000000000' means runtime memory region 

UEFI v2.40 (ARM Fixed Virtual Platform EFI Apr 11 2014 11:55:10, 0x00000000)
Shell> memmap
Type      Start            End              #pages             Attributes
Available 0000000080000000-0000000087FFFFFF 0000000000008000 000000000000000F
Available 000000008C000000-00000000FFAB0FFF 0000000000073AB1 000000000000000F
BS_Data   00000000FFAB1000-00000000FFFFFFFF 000000000000054F 000000000000000F
Available 0000000880000000-00000008FADC2FFF 000000000007ADC3 000000000000000F
LoaderCode 00000008FADC3000-00000008FAEBAFFF 00000000000000F8 000000000000000F
BS_Code   00000008FAEBB000-00000008FAFB2FFF 00000000000000F8 000000000000000F
RT_Code   00000008FAFB3000-00000008FAFBEFFF 000000000000000C 800000000000000F <-- Runtime
RT_Data   00000008FAFBF000-00000008FAFD7FFF 0000000000000019 800000000000000F <-- Runtime
RT_Code   00000008FAFD8000-00000008FAFF4FFF 000000000000001D 800000000000000F <-- Runtime
Available 00000008FAFF5000-00000008FC6DAFFF 00000000000016E6 000000000000000F
BS_Data   00000008FC6DB000-00000008FC74DFFF 0000000000000073 000000000000000F
Available 00000008FC74E000-00000008FC7C0FFF 0000000000000073 000000000000000F
BS_Data   00000008FC7C1000-00000008FC8B8FFF 00000000000000F8 000000000000000F
Available 00000008FC8B9000-00000008FC8D5FFF 000000000000001D 000000000000000F
BS_Data   00000008FC8D6000-00000008FC906FFF 0000000000000031 000000000000000F
Available 00000008FC907000-00000008FC91EFFF 0000000000000018 000000000000000F
BS_Data   00000008FC91F000-00000008FC95CFFF 000000000000003E 000000000000000F
Available 00000008FC95D000-00000008FC973FFF 0000000000000017 000000000000000F
BS_Data   00000008FC974000-00000008FFE28FFF 00000000000034B5 000000000000000F
Available 00000008FFE29000-00000008FFE91FFF 0000000000000069 000000000000000F
BS_Code   00000008FFE92000-00000008FFFB8FFF 0000000000000127 000000000000000F
RT_Code   00000008FFFB9000-00000008FFFCCFFF 0000000000000014 800000000000000F <-- Runtime
RT_Data   00000008FFFCD000-00000008FFFFEFFF 0000000000000032 800000000000000F <-- Runtime
BS_Data   00000008FFFFF000-00000008FFFFFFFF 0000000000000001 000000000000000F
MMIO      000000000C000000-000000000FFEFFFF 0000000000003FF0 8000000000000001 <-- Runtime (NOR Flash)
MMIO      000000001C170000-000000001C170FFF 0000000000000001 8000000000000001 <-- Runtime (RTC controller)
  Reserved  :          0 Pages (0)
  LoaderCode:        248 Pages (1,015,808)
  LoaderData:          0 Pages (0)
  BS_Code   :        543 Pages (2,224,128)
  BS_Data   :     15,327 Pages (62,779,392)
  RT_Code   :         61 Pages (249,856)
  RT_Data   :         75 Pages (307,200)
  ACPI Recl :          0 Pages (0)
  ACPI NVS  :          0 Pages (0)
  MMIO      :     16,369 Pages (67,047,424)
  Available :  1,015,938 Pages (4,161,282,048)
Total Memory: 4095 MB (4,294,905,856 Bytes)
Shell>

Linux

By passing the argument 'uefi_debug', the Linux kernel dumps the UEFI information. Example: 

EFI stub: Booting Linux Kernel...
Initializing cgroup subsys cpu
Linux version 3.14.0-next-20140402+ (gcc version 4.8.3 20131111 (prerelease) (crosstool-NG linaro-1.13.1-4.8-2013.11 - Linaro GCC 2013.10) ) #1 SMP PREEMPT Fri Apr 11 15:39:25 BST 2014
CPU: AArch64 Processor [410fd0f0] revision 0
bootconsole [earlycon0] enabled
efi: Getting parameters from FDT:
efi:   System Table: 0x00000008ffffef18
efi:   MemMap Address: 0x00000008fa366018
efi:   MemMap Size: 0x00000930
efi:   MemMap Desc. Size: 0x00000030
efi:   MemMap Desc. Version: 0x00000001
EFI v2.40 by ARM Fixed Virtual Platform EFI Apr 11 2014 11:55:10
efi: 
Processing EFI memory map:
  0x000080000000-0x000080000fff [Loader Data]
  0x000080001000-0x00008007ffff [Conventional Memory]
  0x000080080000-0x000080655fff [Loader Data]
  0x000080656000-0x000087ffffff [Conventional Memory]
  0x00008c000000-0x00009fdfffff [Conventional Memory]
  0x00009fe00000-0x00009fe03fff [Loader Data]
  0x00009fe04000-0x0000ffab0fff [Conventional Memory]
  0x0000ffab1000-0x0000ffffffff [Boot Data]*
  0x000880000000-0x0008fa365fff [Conventional Memory]
  0x0008fa366000-0x0008fa366fff [Loader Data]
  0x0008fa367000-0x0008fa910fff [Loader Code]
  0x0008fa911000-0x0008fafb2fff [Boot Code]*
  0x0008fafb3000-0x0008fafbefff [Runtime Code]*
  0x0008fafbf000-0x0008fafd7fff [Runtime Data]*
  0x0008fafd8000-0x0008faff4fff [Runtime Code]*
  0x0008faff5000-0x0008fc63cfff [Conventional Memory]
  0x0008fc63d000-0x0008fc74dfff [Boot Data]*
  0x0008fc74e000-0x0008fc7c0fff [Conventional Memory]
  0x0008fc7c1000-0x0008fc8b8fff [Boot Data]*
  0x0008fc8b9000-0x0008fc8d5fff [Conventional Memory]
  0x0008fc8d6000-0x0008fc906fff [Boot Data]*
  0x0008fc907000-0x0008fc91efff [Conventional Memory]
  0x0008fc91f000-0x0008fc937fff [Boot Data]*
  0x0008fc938000-0x0008fc975fff [Conventional Memory]
  0x0008fc976000-0x0008fc981fff [Boot Data]*
  0x0008fc982000-0x0008fc98efff [Conventional Memory]
  0x0008fc98f000-0x0008fc991fff [Boot Data]*
  0x0008fc992000-0x0008fc9b0fff [Conventional Memory]
  0x0008fc9b1000-0x0008fce31fff [Boot Data]*
  0x0008fce32000-0x0008fce80fff [Conventional Memory]
  0x0008fce81000-0x0008ff682fff [Boot Data]*
  0x0008ff683000-0x0008ff685fff [Conventional Memory]
  0x0008ff686000-0x0008ff686fff [Boot Data]*
  0x0008ff687000-0x0008ff698fff [Conventional Memory]
  0x0008ff699000-0x0008ff699fff [Boot Data]*
  0x0008ff69a000-0x0008ff69dfff [Conventional Memory]
  0x0008ff69e000-0x0008ff69efff [Boot Data]*
  0x0008ff69f000-0x0008ff69ffff [Conventional Memory]
  0x0008ff6a0000-0x0008ff6c4fff [Boot Data]*
  0x0008ff6c5000-0x0008ff6cafff [Conventional Memory]
  0x0008ff6cb000-0x0008ffe28fff [Boot Data]*
  0x0008ffe29000-0x0008ffe8efff [Conventional Memory]
  0x0008ffe8f000-0x0008ffe91fff [Loader Data]
  0x0008ffe92000-0x0008fffb8fff [Boot Code]*
  0x0008fffb9000-0x0008fffccfff [Runtime Code]*
  0x0008fffcd000-0x0008ffffefff [Runtime Data]*
  0x0008fffff000-0x0008ffffffff [Boot Data]*
  0x00000c000000-0x00000ffeffff [Memory Mapped I/O]
  0x00001c170000-0x00001c170fff [Memory Mapped I/O]
(...)
Kernel command line: dtb=fvp-base-gicv2-psci.dtb console=ttyAMA0 earlyprintk=pl011,0x1c090000 debug uefi_debug root=/dev/vda2 rw
(...)
Remapping and enabling EFI services.
  EFI remap 0x0008fafb3000 => ffffffc87afb3000
  EFI remap 0x0008fafbf000 => ffffffc87afbf000
  EFI remap 0x0008fafd8000 => ffffffc87afd8000
  EFI remap 0x0008fffb9000 => ffffffc87ffb9000
  EFI remap 0x0008fffcd000 => ffffffc87ffcd000
  EFI remap 0x00000c000000 => ffffff8000080000
  EFI remap 0x00001c170000 => ffffff8000012000
  EFI freeing: 0x0000ffab1000-0x0000ffffffff
  EFI freeing: 0x0008fa911000-0x0008fafb2fff
  EFI freeing: 0x0008fc63d000-0x0008fc74dfff
  EFI freeing: 0x0008fc7c1000-0x0008fc8b8fff
  EFI freeing: 0x0008fc8d6000-0x0008fc906fff
  EFI freeing: 0x0008fc91f000-0x0008fc937fff
  EFI freeing: 0x0008fc976000-0x0008fc981fff
  EFI freeing: 0x0008fc98f000-0x0008fc991fff
  EFI freeing: 0x0008fc9b1000-0x0008fce31fff
  EFI freeing: 0x0008fce81000-0x0008ff682fff
  EFI freeing: 0x0008ff686000-0x0008ff686fff
  EFI freeing: 0x0008ff699000-0x0008ff699fff
  EFI freeing: 0x0008ff69e000-0x0008ff69efff
  EFI freeing: 0x0008ff6a0000-0x0008ff6c4fff
  EFI freeing: 0x0008ff6cb000-0x0008ffe28fff
  EFI freeing: 0x0008ffe92000-0x0008fffb8fff
  EFI freeing: 0x0008fffff000-0x0008ffffffff
Freed 0x4384000 bytes of EFI boot services memory
(...)

Accessing the UEFI variables from the Linux terminal: 

root@genericarmv8:~# efibootmgr -d /dev/vda
BootCurrent: 0003
Timeout: 5 seconds
BootOrder: 0003
Boot0000* Linux from SemiHosting
Boot0003  EFI Stub
Boot0005* grub
root@genericarmv8:~#

Debugging

To debug UEFI Runtime services, you could have a look at the 'Validation' section to ensure your UEFI Services behave as expected.

If the UEFI Runtime Services are not implemented correctly, your Operating System would crash when accessing them.

Use Case 1: EfiConvertPointer()

1. Trigger the crash in Linux. Keep the failing virtual address and the values of the PC and LR registers. center

  • Failing Virtual Adress: 0xffaae850
  • PC: 0xffffffc0031c473c
  • LR: 0xffffffc0031c4710
2. Get the remapped UEFI Runtime regions of the Linux Virtual Memory map center ... and find out which region the failing values are part of:
  • 0x0000831b7000 => 0xffffffc0031b7000
  • 0x0000ffa99000 => 0xffffffc07fa99000
And calculate the offset (it is likely the offsets are the same for each mapping).
In our case the offste is 0xFFFFFFBF80000000 for both ranges.

From this offset, we can get the corresponding PC value into the UEFI space: 0x831C473C

3. Restart UEFI and load the symbols.
Set a breakpoint (or go to the PC location) center From this window, we can see the 'Fvb' variable is at 0xffaae840. 'Fvb->GetPhysicalAddress()' is actually at 0xffaae850.
We can conclude that the Linux kernel was still accessing the address of Fvb->GetPhysicalAddress in the UEFI memory view.

The fix is to convert this address when the Operating System notifies the change of the Virtual Memory map to the UEFI Runtime Services: 

VOID
EFIAPI
NorFlashVirtualNotifyEvent (
  IN EFI_EVENT        Event,
  IN VOID             *Context
  )
{
  (..)
  EfiConvertPointer (0x0, (VOID**)&mNorFlashInstance->FvbProtocol.GetPhysicalAddress);
  (..)
}

Use Case 2: Boot Service API

1. Get the information from the crash
center

2. Restart UEFI and load the symbols.
Set a breakpoint (or go to the PC location)
center

Conclusion: AllocatePool (UEFI Boot Services function) is invoked during the UEFI Runtime phase (after gBS->ExitBootServices() is called).
It is illegal!

Use Case 3: Direct access to hardware registers

1. Get the information from the crash
center

0x0c00_0000 is actually the NOR Flash address (see: http://infocenter.arm.com/help/topic/com.arm.doc.dui0677c/BBACIHDC.html). The UEFI Runtime NOR Flash driver accessed the hardware region without updating the base address into the Linux Virtual Memory Map.

To identify which part of the driver is accessing the hardware register, we load the symbols into the Linux Memory map.
In UEFI Memory map: 

Add symbols of /home/olimar01/tianocore/Build/ArmVExpress-FVP-AArch64/DEBUG_GCC48/AARCH64/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe/DEBUG/ArmVeNorFlashDxe.dll at 0x831d4260

After converting the UEFI address into the Linux Memory Map (and force the symbols to be loaded in EL1 Non-Secure world): 

add-symbol-file /home/olimar01/tianocore/Build/ArmVExpress-FVP-AArch64/DEBUG_GCC48/AARCH64/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe/DEBUG/ArmVeNorFlashDxe.dll EL1N:0xFFFFFFC0031D4260

2. Restart the environment. Load the symbols and add the breakpoint: 

add-symbol-file /home/olimar01/tianocore/Build/ArmVExpress-FVP-AArch64/DEBUG_GCC48/AARCH64/ArmPlatformPkg/Drivers/NorFlashDxe/NorFlashDxe/DEBUG/ArmVeNorFlashDxe.dll EL1N:0xFFFFFFC0031D4260
hbreak -p EL1N:0xffffffc0031d8e14
center

Conclusion: Fixing up Instance->DeviceAddress (physical address of the NOR Flash device) when the virtual memory map is changed at Runtime should fix the issue.

Tuning

We saw earlier there were multiple UEFI Data and Code Runtime regions in the EFI Shell. 

UEFI v2.40 (ARM Fixed Virtual Platform EFI Apr 11 2014 11:55:10, 0x00000000)
Shell> memmap
Type      Start            End              #pages             Attributes
Available 0000000080000000-0000000087FFFFFF 0000000000008000 000000000000000F
Available 000000008C000000-00000000FFAB0FFF 0000000000073AB1 000000000000000F
BS_Data   00000000FFAB1000-00000000FFFFFFFF 000000000000054F 000000000000000F
Available 0000000880000000-00000008FADC2FFF 000000000007ADC3 000000000000000F
LoaderCode 00000008FADC3000-00000008FAEBAFFF 00000000000000F8 000000000000000F
BS_Code   00000008FAEBB000-00000008FAFB2FFF 00000000000000F8 000000000000000F
RT_Code   00000008FAFB3000-00000008FAFBEFFF 000000000000000C 800000000000000F <-- Runtime
RT_Data   00000008FAFBF000-00000008FAFD7FFF 0000000000000019 800000000000000F <-- Runtime
RT_Code   00000008FAFD8000-00000008FAFF4FFF 000000000000001D 800000000000000F <-- Runtime
Available 00000008FAFF5000-00000008FC6DAFFF 00000000000016E6 000000000000000F
BS_Data   00000008FC6DB000-00000008FC74DFFF 0000000000000073 000000000000000F
Available 00000008FC74E000-00000008FC7C0FFF 0000000000000073 000000000000000F
BS_Data   00000008FC7C1000-00000008FC8B8FFF 00000000000000F8 000000000000000F
Available 00000008FC8B9000-00000008FC8D5FFF 000000000000001D 000000000000000F
BS_Data   00000008FC8D6000-00000008FC906FFF 0000000000000031 000000000000000F
Available 00000008FC907000-00000008FC91EFFF 0000000000000018 000000000000000F
BS_Data   00000008FC91F000-00000008FC95CFFF 000000000000003E 000000000000000F
Available 00000008FC95D000-00000008FC973FFF 0000000000000017 000000000000000F
BS_Data   00000008FC974000-00000008FFE28FFF 00000000000034B5 000000000000000F
Available 00000008FFE29000-00000008FFE91FFF 0000000000000069 000000000000000F
BS_Code   00000008FFE92000-00000008FFFB8FFF 0000000000000127 000000000000000F
RT_Code   00000008FFFB9000-00000008FFFCCFFF 0000000000000014 800000000000000F <-- Runtime
RT_Data   00000008FFFCD000-00000008FFFFEFFF 0000000000000032 800000000000000F <-- Runtime
BS_Data   00000008FFFFF000-00000008FFFFFFFF 0000000000000001 000000000000000F
MMIO      000000000C000000-000000000FFEFFFF 0000000000003FF0 8000000000000001 <-- Runtime (NOR Flash)
MMIO      000000001C170000-000000001C170FFF 0000000000000001 8000000000000001 <-- Runtime (RTC controller)
  Reserved  :          0 Pages (0)
  LoaderCode:        248 Pages (1,015,808)
  LoaderData:          0 Pages (0)
  BS_Code   :        543 Pages (2,224,128)
  BS_Data   :     15,327 Pages (62,779,392)
  RT_Code   :         61 Pages (249,856) <-- Runtime Code regions
  RT_Data   :         75 Pages (307,200) <-- Runtime Data regions
  ACPI Recl :          0 Pages (0)
  ACPI NVS  :          0 Pages (0)
  MMIO      :     16,369 Pages (67,047,424)
  Available :  1,015,938 Pages (4,161,282,048)
Total Memory: 4095 MB (4,294,905,856 Bytes)
Shell>

These fragmented UEFI regions would still appear fragmented when booting Linux: 

Remapping and enabling EFI services.
  EFI remap 0x0008fafb3000 => ffffffc87afb3000
  EFI remap 0x0008fafbf000 => ffffffc87afbf000
  EFI remap 0x0008fafd8000 => ffffffc87afd8000
  EFI remap 0x0008fffb9000 => ffffffc87ffb9000
  EFI remap 0x0008fffcd000 => ffffffc87ffcd000
  EFI remap 0x00000c000000 => ffffff8000080000
  EFI remap 0x00001c170000 => ffffff8000012000

These regions can get unify by declaring EFI_MEMORY_TYPE_INFORMATION using the gEfiMemoryTypeInformationGuid HOB.
Support for this HOB already exists in the ARM Platform framework, you only need to:

  • Set PcdPrePiProduceMemoryTypeInformationHob to TRUE
  • Define the number of pages for the Runtime Data and Code regions:
--- a/ArmPlatformPkg/ArmVExpressPkg/ArmVExpress.dsc.inc
+++ b/ArmPlatformPkg/ArmVExpressPkg/ArmVExpress.dsc.inc
@@ -318,8 +318,8 @@
   gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiACPIReclaimMemory|0
   gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiACPIMemoryNVS|0
   gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiReservedMemoryType|0
-  gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiRuntimeServicesData|50
-  gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiRuntimeServicesCode|20
+  gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiRuntimeServicesData|80
+  gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiRuntimeServicesCode|65
   gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiBootServicesCode|400
   gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiBootServicesData|20000
   gEmbeddedTokenSpaceGuid.PcdMemoryTypeEfiLoaderCode|20

After rebuilding the UEFI firmware, your regions should now be unified: 

Shell> memmap
Type      Start            End              #pages             Attributes
Available 0000000080000000-0000000087FFFFFF 0000000000008000 000000000000000F
Available 000000008C000000-00000000FFAB2FFF 0000000000073AB3 000000000000000F
BS_Data   00000000FFAB3000-00000000FFFFFFFF 000000000000054D 000000000000000F
Available 0000000880000000-00000008FACC1FFF 000000000007ACC2 000000000000000F
LoaderCode 00000008FACC2000-00000008FADB9FFF 00000000000000F8 000000000000000F
BS_Code   00000008FADBA000-00000008FAFA9FFF 00000000000001F0 000000000000000F
Available 00000008FAFAA000-00000008FC5F6FFF 000000000000164D 000000000000000F
BS_Data   00000008FC5F7000-00000008FC707FFF 0000000000000111 000000000000000F
Available 00000008FC708000-00000008FC755FFF 000000000000004E 000000000000000F
BS_Data   00000008FC756000-00000008FC872FFF 000000000000011D 000000000000000F
Available 00000008FC873000-00000008FC88FFFF 000000000000001D 000000000000000F
BS_Data   00000008FC890000-00000008FC8C0FFF 0000000000000031 000000000000000F
Available 00000008FC8C1000-00000008FC8D8FFF 0000000000000018 000000000000000F
BS_Data   00000008FC8D9000-00000008FC8F1FFF 0000000000000019 000000000000000F
Available 00000008FC8F2000-00000008FC92DFFF 000000000000003C 000000000000000F
BS_Data   00000008FC92E000-00000008FC93BFFF 000000000000000E 000000000000000F
Available 00000008FC93C000-00000008FC948FFF 000000000000000D 000000000000000F
BS_Data   00000008FC949000-00000008FC94BFFF 0000000000000003 000000000000000F
Available 00000008FC94C000-00000008FC96AFFF 000000000000001F 000000000000000F
BS_Data   00000008FC96B000-00000008FCDEBFFF 0000000000000481 000000000000000F
Available 00000008FCDEC000-00000008FCE03FFF 0000000000000018 000000000000000F
BS_Data   00000008FCE04000-00000008FCE25FFF 0000000000000022 000000000000000F
Available 00000008FCE26000-00000008FCE2CFFF 0000000000000007 000000000000000F
BS_Data   00000008FCE2D000-00000008FF643FFF 0000000000002817 000000000000000F
Available 00000008FF644000-00000008FF644FFF 0000000000000001 000000000000000F
BS_Data   00000008FF645000-00000008FF649FFF 0000000000000005 000000000000000F
Available 00000008FF64A000-00000008FF64AFFF 0000000000000001 000000000000000F
BS_Data   00000008FF64B000-00000008FFDDDFFF 0000000000000793 000000000000000F
Available 00000008FFDDE000-00000008FFE47FFF 000000000000006A 000000000000000F
BS_Code   00000008FFE48000-00000008FFF6DFFF 0000000000000126 000000000000000F
RT_Code   00000008FFF6E000-00000008FFFAEFFF 0000000000000041 800000000000000F <-- Runtime
RT_Data   00000008FFFAF000-00000008FFFFEFFF 0000000000000050 800000000000000F <-- Runtime
BS_Data   00000008FFFFF000-00000008FFFFFFFF 0000000000000001 000000000000000F
MMIO      000000000C000000-000000000FFEFFFF 0000000000003FF0 8000000000000001 <-- Runtime
MMIO      000000001C170000-000000001C170FFF 0000000000000001 8000000000000001 <-- Runtime
  Reserved  :          0 Pages (0)
  LoaderCode:        248 Pages (1,015,808)
  LoaderData:          0 Pages (0)
  BS_Code   :        790 Pages (3,235,840)
  BS_Data   :     15,401 Pages (63,082,496)
  RT_Code   :         65 Pages (266,240) <-- Runtime Code regions
  RT_Data   :         80 Pages (327,680) <-- Runtime Data regions
  ACPI Recl :          0 Pages (0)
  ACPI NVS  :          0 Pages (0)
  MMIO      :     16,369 Pages (67,047,424)
  Available :  1,015,608 Pages (4,159,930,368)
Total Memory: 4095 MB (4,294,905,856 Bytes)
Shell>

And when booting Linux: 

Remapping and enabling EFI services.
  EFI remap 0x0008fff6e000 => ffffffc87ff6e000
  EFI remap 0x0008fffaf000 => ffffffc87ffaf000
  EFI remap 0x00000c000000 => ffffff8000080000
  EFI remap 0x00001c170000 => ffffff8000012000

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