Re: [PATCH v2 11/14] ArmVirtPkg/ArmVirtQemu: add ArmVirtMemInfoLib implementation

[Laszlo Ersek <lersek@redhat.com>]

On 11/22/17 11:07, Ard Biesheuvel wrote:
> 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>
> ---
>  ArmVirtPkg/ArmVirtQemuKernel.dsc                             |   1 +
>  ArmVirtPkg/Library/QemuVirtMemInfoLib/AArch64/PhysAddrTop.S  |  39 ++++++++
>  ArmVirtPkg/Library/QemuVirtMemInfoLib/Arm/PhysAddrTop.S      |  24 +++++
>  ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.c   | 100 ++++++++++++++++++++
>  ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.inf |  54 +++++++++++
>  5 files changed, 218 insertions(+)
> 
> diff --git a/ArmVirtPkg/ArmVirtQemuKernel.dsc b/ArmVirtPkg/ArmVirtQemuKernel.dsc
> index 7e5d584344b4..f50d30388cf2 100644
> --- a/ArmVirtPkg/ArmVirtQemuKernel.dsc
> +++ b/ArmVirtPkg/ArmVirtQemuKernel.dsc
> @@ -49,6 +49,7 @@ [LibraryClasses.common]
>    QemuFwCfgS3Lib|OvmfPkg/Library/QemuFwCfgS3Lib/BaseQemuFwCfgS3LibNull.inf
>  
>    ArmPlatformLib|ArmVirtPkg/Library/ArmQemuRelocatablePlatformLib/ArmQemuRelocatablePlatformLib.inf
> +  ArmVirtMemInfoLib|ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.inf
>  
>    TimerLib|ArmPkg/Library/ArmArchTimerLib/ArmArchTimerLib.inf
>    NorFlashPlatformLib|ArmVirtPkg/Library/NorFlashQemuLib/NorFlashQemuLib.inf
> diff --git a/ArmVirtPkg/Library/QemuVirtMemInfoLib/AArch64/PhysAddrTop.S b/ArmVirtPkg/Library/QemuVirtMemInfoLib/AArch64/PhysAddrTop.S
> new file mode 100644
> index 000000000000..a1f6a194d59b
> --- /dev/null
> +++ b/ArmVirtPkg/Library/QemuVirtMemInfoLib/AArch64/PhysAddrTop.S
> @@ -0,0 +1,39 @@
> +#
> +#  Copyright (c) 2011-2013, ARM Limited. All rights reserved.
> +#  Copyright (c) 2016-2017, Linaro Limited. All rights reserved.
> +#
> +#  This program and the accompanying materials
> +#  are licensed and made available under the terms and conditions of the BSD License
> +#  which accompanies this distribution.  The full text of the license may be found at
> +#  http://opensource.org/licenses/bsd-license.php
> +#
> +#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> +#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> +#
> +#
> +
> +#include <AsmMacroIoLibV8.h>
> +
> +//EFI_PHYSICAL_ADDRESS
> +//GetPhysAddrTop (
> +//  VOID
> +//  );
> +ASM_FUNC(ArmGetPhysAddrTop)
> +  mrs   x0, id_aa64mmfr0_el1
> +  adr   x1, .LPARanges
> +  and   x0, x0, #7
> +  ldrb  w1, [x1, x0]
> +  mov   x0, #1
> +  lsl   x0, x0, x1
> +  ret
> +
> +//
> +// Bits 0..2 of the AA64MFR0_EL1 system register encode the size of the
> +// physical address space support on this CPU:
> +// 0 == 32 bits, 1 == 36 bits, etc etc
> +// 6 and 7 are reserved
> +//
> +.LPARanges:
> +  .byte 32, 36, 40, 42, 44, 48, -1, -1
> +
> +ASM_FUNCTION_REMOVE_IF_UNREFERENCED
> diff --git a/ArmVirtPkg/Library/QemuVirtMemInfoLib/Arm/PhysAddrTop.S b/ArmVirtPkg/Library/QemuVirtMemInfoLib/Arm/PhysAddrTop.S
> new file mode 100644
> index 000000000000..9cd81529fb3d
> --- /dev/null
> +++ b/ArmVirtPkg/Library/QemuVirtMemInfoLib/Arm/PhysAddrTop.S
> @@ -0,0 +1,24 @@
> +#
> +#  Copyright (c) 2011-2013, ARM Limited. All rights reserved.
> +#  Copyright (c) 2014-2017, Linaro Limited. All rights reserved.
> +#
> +#  This program and the accompanying materials
> +#  are licensed and made available under the terms and conditions of the BSD License
> +#  which accompanies this distribution.  The full text of the license may be found at
> +#  http://opensource.org/licenses/bsd-license.php
> +#
> +#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> +#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> +#
> +#
> +
> +#include <AsmMacroIoLib.h>
> +
> +//EFI_PHYSICAL_ADDRESS
> +//GetPhysAddrTop (
> +//  VOID
> +//  );
> +ASM_FUNC(ArmGetPhysAddrTop)
> +  mov   r0, #0x00000000
> +  mov   r1, #0x10000
> +  bx    lr
> diff --git a/ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.c b/ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.c
> new file mode 100644
> index 000000000000..ea70f2c33b77
> --- /dev/null
> +++ b/ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.c
> @@ -0,0 +1,100 @@
> +/** @file
> +
> +  Copyright (c) 2014-2017, Linaro Limited. All rights reserved.
> +
> +  This program and the accompanying materials are licensed and made available
> +  under the terms and conditions of the BSD License which accompanies this
> +  distribution.  The full text of the license may be found at
> +  http://opensource.org/licenses/bsd-license.php
> +
> +  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> +  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> +
> +**/
> +
> +#include <Base.h>
> +#include <Library/ArmLib.h>
> +#include <Library/BaseMemoryLib.h>
> +#include <Library/DebugLib.h>
> +#include <Library/MemoryAllocationLib.h>
> +
> +// 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
> +
> +  This Virtual Memory Map is used by MemoryInitPei Module to initialize the MMU
> +  on your platform.
> +
> +  @param[out]   VirtualMemoryMap    Array of ARM_MEMORY_REGION_DESCRIPTOR
> +                                    describing a Physical-to-Virtual Memory
> +                                    mapping. This array must be ended by a
> +                                    zero-filled entry. The allocated memory
> +                                    will not be freed.
> +
> +**/
> +VOID
> +ArmVirtGetMemoryMap (
> +  OUT ARM_MEMORY_REGION_DESCRIPTOR   **VirtualMemoryMap
> +  )
> +{
> +  ARM_MEMORY_REGION_DESCRIPTOR  *VirtualMemoryTable;
> +  UINT64                        TopOfMemory;
> +
> +  ASSERT (VirtualMemoryMap != NULL);
> +
> +  VirtualMemoryTable = AllocatePool (sizeof (ARM_MEMORY_REGION_DESCRIPTOR) *
> +                                     MAX_VIRTUAL_MEMORY_MAP_DESCRIPTORS);

Pool allocations like this are satisfied from HOBs, before permanent PEI
RAM is installed. As part of the temp RAM migration, the HOBs are moved,
and the previous addresses become invalid. (This is not true for memory
allocated with AllocatePages().)

However, I think in this specific case that should be fine. We actually
don't want or need this allocation to stick around forever; the caller
(InitMmu()) uses it immediately. And, as far as I can see in InitMmu(),
the address of the map is not remembered. So this should be fine.

> +
> +  if (VirtualMemoryTable == NULL) {
> +    DEBUG ((DEBUG_ERROR, "%a: Error: Failed AllocatePages()\n", __FUNCTION__));
> +    return;
> +  }

Not very important, but before pushing, please update the error message
to say AllocatePool().

Reviewed-by: Laszlo Ersek <lersek@redhat.com>

Thanks
Laszlo

> +
> +  // System DRAM
> +  VirtualMemoryTable[0].PhysicalBase = PcdGet64 (PcdSystemMemoryBase);
> +  VirtualMemoryTable[0].VirtualBase  = VirtualMemoryTable[0].PhysicalBase;
> +  VirtualMemoryTable[0].Length       = PcdGet64 (PcdSystemMemorySize);
> +  VirtualMemoryTable[0].Attributes   = ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK;
> +
> +  DEBUG ((DEBUG_INFO, "%a: Dumping System DRAM Memory Map:\n"
> +      "\tPhysicalBase: 0x%lX\n"
> +      "\tVirtualBase: 0x%lX\n"
> +      "\tLength: 0x%lX\n",
> +      __FUNCTION__,
> +      VirtualMemoryTable[0].PhysicalBase,
> +      VirtualMemoryTable[0].VirtualBase,
> +      VirtualMemoryTable[0].Length));
> +
> +  // Peripheral space before DRAM
> +  VirtualMemoryTable[1].PhysicalBase = 0x0;
> +  VirtualMemoryTable[1].VirtualBase  = 0x0;
> +  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;
> +
> +  // End of Table
> +  ZeroMem (&VirtualMemoryTable[4], sizeof (ARM_MEMORY_REGION_DESCRIPTOR));
> +
> +  *VirtualMemoryMap = VirtualMemoryTable;
> +}
> diff --git a/ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.inf b/ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.inf
> new file mode 100644
> index 000000000000..c72a97f9e78a
> --- /dev/null
> +++ b/ArmVirtPkg/Library/QemuVirtMemInfoLib/QemuVirtMemInfoLib.inf
> @@ -0,0 +1,54 @@
> +#/* @file
> +#
> +#  Copyright (c) 2011-2015, ARM Limited. All rights reserved.
> +#  Copyright (c) 2014-2017, Linaro Limited. All rights reserved.
> +#
> +#  This program and the accompanying materials are licensed and made available
> +#  under the terms and conditions of the BSD License which accompanies this
> +#  distribution.  The full text of the license may be found at
> +#  http://opensource.org/licenses/bsd-license.php
> +#
> +#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> +#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> +#
> +#*/
> +
> +[Defines]
> +  INF_VERSION                    = 0x0001001A
> +  BASE_NAME                      = QemuVirtMemInfoLib
> +  FILE_GUID                      = 9b30ca82-6746-4a82-a3e6-11ea79df3b46
> +  MODULE_TYPE                    = BASE
> +  VERSION_STRING                 = 1.0
> +  LIBRARY_CLASS                  = ArmVirtMemInfoLib
> +
> +[Sources]
> +  QemuVirtMemInfoLib.c
> +
> +[Sources.ARM]
> +  Arm/PhysAddrTop.S
> +
> +[Sources.AARCH64]
> +  AArch64/PhysAddrTop.S
> +
> +[Packages]
> +  ArmPkg/ArmPkg.dec
> +  ArmVirtPkg/ArmVirtPkg.dec
> +  EmbeddedPkg/EmbeddedPkg.dec
> +  MdeModulePkg/MdeModulePkg.dec
> +  MdePkg/MdePkg.dec
> +
> +[LibraryClasses]
> +  ArmLib
> +  BaseMemoryLib
> +  DebugLib
> +  MemoryAllocationLib
> +  PcdLib
> +
> +[Pcd]
> +  gArmTokenSpaceGuid.PcdFdBaseAddress
> +  gArmTokenSpaceGuid.PcdSystemMemoryBase
> +  gArmTokenSpaceGuid.PcdSystemMemorySize
> +
> +[FixedPcd]
> +  gArmTokenSpaceGuid.PcdFdSize
> +  gEmbeddedTokenSpaceGuid.PcdPrePiCpuMemorySize
>