Re: [PATCH 1/2] Platform/ARM/Sgi: Install a Platform ID HOB

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

Hello Chandni,

On 15 June 2018 at 07:55, Chandni Cherukuri <chandni.cherukuri@arm.com> wrote:
> On SGI platforms, the trusted firmware executes prior to
> the SEC phase. It supplies to the SEC phase a pointer to
> a fdt, that contains platform specific information such as
> part number and config number of the SGI platform. The
> platform code that executes during the SEC phase creates a
> PPI that allows access to other PEIMs to obtain a copy of the
> fdt pointer.
>
> Further, during the PEI phase, a Platform ID PEIM installs a
> Platform ID HOB. The Platform ID HOB can be used by DXE
> drivers to identify the platform it is executing on.
>
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Chandni Cherukuri <chandni.cherukuri@arm.com>
> ---
>  .../SgiPkg/Library/PlatformLib/AArch64/Helper.S    |  15 ++-
>  .../ARM/SgiPkg/Library/PlatformLib/PlatformLib.c   |  10 ++
>  .../ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf |   3 +
>  .../Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c  | 108 +++++++++++++++++++++
>  .../SgiPlatformPeiLib/SgiPlatformPeiLib.inf        |  40 ++++++++
>  Platform/ARM/SgiPkg/SgiPlatform.dec                |   5 +
>  6 files changed, 177 insertions(+), 4 deletions(-)
>  create mode 100644 Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c
>  create mode 100644 Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.inf
>

Please use '--stat=250 --stat-graph-width=20' when using git
format-patch so that we get to see the entire path names in the
diffstat

> diff --git a/Platform/ARM/SgiPkg/Library/PlatformLib/AArch64/Helper.S b/Platform/ARM/SgiPkg/Library/PlatformLib/AArch64/Helper.S
> index dab6c77..80b93ea 100644
> --- a/Platform/ARM/SgiPkg/Library/PlatformLib/AArch64/Helper.S
> +++ b/Platform/ARM/SgiPkg/Library/PlatformLib/AArch64/Helper.S
> @@ -22,15 +22,22 @@ GCC_ASM_EXPORT(ArmPlatformPeiBootAction)
>  GCC_ASM_EXPORT(ArmPlatformGetCorePosition)
>  GCC_ASM_EXPORT(ArmPlatformGetPrimaryCoreMpId)
>  GCC_ASM_EXPORT(ArmPlatformIsPrimaryCore)
> +GCC_ASM_EXPORT(HwConfigDtBlob)
> +
> +HwConfigDtBlob: .long 0
>

Please move this definition to PlatformLib.c

>  //
>  // First platform specific function to be called in the PEI phase
>  //
> -// This function is actually the first function called by the PrePi
> -// or PrePeiCore modules. It allows to retrieve arguments passed to
> -// the UEFI firmware through the CPU registers.
> -//
> +// The trusted firmware passed the hw config DT blob in x1 register.
> +// Keep a copy of it in a global variable.
> +//VOID
> +//ArmPlatformPeiBootAction (
> +//  VOID
> +//  );
>  ASM_PFX(ArmPlatformPeiBootAction):
> +  ldr  x10, =HwConfigDtBlob

Please use adr to take the address of HwConfigDtBlob

> +  str  x1, [x10]
>    ret
>
>  //UINTN
> diff --git a/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.c b/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.c
> index ea3201a..54860e0 100644
> --- a/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.c
> +++ b/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.c
> @@ -15,6 +15,10 @@
>  #include <Library/ArmPlatformLib.h>
>  #include <Library/BaseLib.h>
>  #include <Ppi/ArmMpCoreInfo.h>
> +#include <SgiPlatform.h>
> +
> +extern UINT64 HwConfigDtBlob;
> +STATIC SGI_HW_CONFIG_INFO_PPI mHwConfigDtInfoPpi;
>

Where is this PPI declared? A PPI is like a protocol, it has its own
declaration in a header file under Include/Ppi in the package

>  STATIC ARM_CORE_INFO mCoreInfoTable[] = {
>    {
> @@ -36,6 +40,7 @@ ArmPlatformInitialize (
>    IN  UINTN                     MpId
>    )
>  {
> +  mHwConfigDtInfoPpi.HwConfigDtAddr = &HwConfigDtBlob;
>    return RETURN_SUCCESS;
>  }
>
> @@ -59,6 +64,11 @@ EFI_PEI_PPI_DESCRIPTOR gPlatformPpiTable[] = {
>      EFI_PEI_PPI_DESCRIPTOR_PPI,
>      &gArmMpCoreInfoPpiGuid,
>      &mMpCoreInfoPpi
> +  },
> +  {
> +    EFI_PEI_PPI_DESCRIPTOR_PPI,
> +    &gHwConfigDtInfoPpiGuid,
> +    &mHwConfigDtInfoPpi
>    }
>  };
>
> diff --git a/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf b/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf
> index 42e14d5..5d4bf72 100644
> --- a/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf
> +++ b/Platform/ARM/SgiPkg/Library/PlatformLib/PlatformLib.inf
> @@ -61,7 +61,10 @@
>    gEfiMdePkgTokenSpaceGuid.PcdPciExpressBaseAddress
>
>  [Guids]
> +  gArmSgiPlatformIdDescriptorGuid
>    gEfiHobListGuid          ## CONSUMES  ## SystemTable
> +  gFdtTableGuid
>
>  [Ppis]
>    gArmMpCoreInfoPpiGuid
> +  gHwConfigDtInfoPpiGuid
> diff --git a/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c b/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c
> new file mode 100644
> index 0000000..f6446e6
> --- /dev/null
> +++ b/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.c
> @@ -0,0 +1,108 @@
> +/** @file
> +*
> +*  Copyright (c) 2018, ARM 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 <Library/DebugLib.h>
> +#include <Library/HobLib.h>
> +#include <Library/PeimEntryPoint.h>
> +#include <Library/PeiServicesLib.h>
> +#include <libfdt.h>
> +#include <SgiPlatform.h>
> +
> +/**
> +
> +  This function returns the Platform ID of the platform
> +
> +  This functions locates the HwConfig PPI and gets the base address of HW CONFIG
> +  DT from which the platform ID is obtained using FDT helper functions
> +
> +  @return returns the platform ID on success else returns 0 on error
> +
> +**/
> +
> +STATIC
> +UINT32
> +GetSgiPlatformId (
> + VOID
> +)
> +{
> +  CONST UINT32                  *Property;
> +  INT32                         Offset;
> +  CONST VOID                    *HwCfgDtBlob;
> +  SGI_HW_CONFIG_INFO_PPI        *HwConfigInfoPpi;
> +  EFI_STATUS                    Status;
> +
> +  Status = PeiServicesLocatePpi (&gHwConfigDtInfoPpiGuid, 0, NULL, (VOID**)&HwConfigInfoPpi);

Please check all your patches for overly long lines. 80 columns is that maximum

> +  if (EFI_ERROR (Status)) {
> +    DEBUG ((DEBUG_ERROR, "PeiServicesLocatePpi failed with error %r\n", Status));
> +    return 0;
> +  }
> +
> +  HwCfgDtBlob = (VOID *)(*(HwConfigInfoPpi->HwConfigDtAddr));
> +  if (fdt_check_header (HwCfgDtBlob) != 0 ) {
> +    DEBUG ((DEBUG_ERROR, "Invalid DTB file %p passed as HW_CONFIG\n", HwCfgDtBlob));
> +    return 0;
> +  }
> +
> +  Offset = fdt_subnode_offset (HwCfgDtBlob, 0, "system-id");
> +  if (Offset == -FDT_ERR_NOTFOUND) {
> +    DEBUG ((DEBUG_ERROR, "Invalid DTB : system-id node not found\n"));
> +    return 0;
> +  }
> +
> +  Property = fdt_getprop (HwCfgDtBlob, Offset, "platform-id", NULL);
> +  if (Property == NULL) {
> +    DEBUG ((DEBUG_ERROR, "Platform Id is NULL\n"));
> +    return 0;
> +  }
> +
> +  return fdt32_to_cpu (*Property);
> +}
> +
> +/**
> +
> + This function creates a Platform ID HOB and assigns PlatformId as the
> + HobData
> +
> + @return asserts on error and returns EFI_INVALID_PARAMETER. On success
> + returns EFI_SUCCESS
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +SgiPlatformIdPeim (
> + IN       EFI_PEI_FILE_HANDLE  FileHandle,
> + IN CONST EFI_PEI_SERVICES     **PeiServices
> +)
> +{
> +  SGI_PLATFORM_DESCRIPTOR       *HobData;
> +
> +  //Create platform descriptor HOB
> +  HobData = (SGI_PLATFORM_DESCRIPTOR *)BuildGuidHob (&gArmSgiPlatformIdDescriptorGuid,
> +            sizeof (SGI_PLATFORM_DESCRIPTOR));
> +
> +  //Get the platform id from the platform specific hw_config device tree
> +  if (HobData != NULL) {

Please invert the sense of this conditional, and return
EFI_OUT_OF_RESOURCES if HobData is NULL

> +    HobData->PlatformId = GetSgiPlatformId ();
> +    if (HobData->PlatformId == 0) {
> +      ASSERT (FALSE);
> +      return EFI_INVALID_PARAMETER;
> +    }
> +  } else {

After you have inverted the if() condition, you can drop the else as well

> +    DEBUG ((DEBUG_ERROR, "Platform HoB is NULL\n"));
> +    ASSERT (FALSE);
> +    return EFI_INVALID_PARAMETER;
> +  }
> +
> +  return EFI_SUCCESS;
> +}
> diff --git a/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.inf b/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.inf
> new file mode 100644
> index 0000000..502d6ac
> --- /dev/null
> +++ b/Platform/ARM/SgiPkg/Library/SgiPlatformPeiLib/SgiPlatformPeiLib.inf
> @@ -0,0 +1,40 @@
> +#
> +#  Copyright (c) 2018, ARM 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                      = SgiPlatformIdPeiLib
> +  FILE_GUID                      = a9936f3e-6a1b-11e8-8ce0-fffe69b86863
> +  MODULE_TYPE                    = PEIM
> +  VERSION_STRING                 = 1.0
> +  ENTRY_POINT                    = SgiPlatformIdPeim
> +
> +[Packages]
> +  EmbeddedPkg/EmbeddedPkg.dec
> +  MdePkg/MdePkg.dec
> +  Platform/ARM/SgiPkg/SgiPlatform.dec
> +
> +[LibraryClasses]
> +  FdtLib
> +  PeimEntryPoint
> +
> +[Sources]
> +  SgiPlatformPeiLib.c
> +
> +[Guids]
> +  gArmSgiPlatformIdDescriptorGuid
> +
> +[Ppis]
> +  gHwConfigDtInfoPpiGuid
> +
> +[Depex]
> +  TRUE
> diff --git a/Platform/ARM/SgiPkg/SgiPlatform.dec b/Platform/ARM/SgiPkg/SgiPlatform.dec
> index d995937..ea9f6c5 100644
> --- a/Platform/ARM/SgiPkg/SgiPlatform.dec
> +++ b/Platform/ARM/SgiPkg/SgiPlatform.dec
> @@ -29,9 +29,14 @@
>    Include                        # Root include for the package
>
>  [Guids.common]
> +  # ARM Sgi Platform ID descriptor
> +  gArmSgiPlatformIdDescriptorGuid = { 0xf56f152a, 0xad2a, 0x11e6, { 0xb1, 0xa7, 0x00, 0x50, 0x56, 0x3c, 0x44, 0xcc } }
>    gArmSgiTokenSpaceGuid      = { 0x577d6941, 0xaea1, 0x40b4, { 0x90, 0x93, 0x2a, 0x86, 0x61, 0x72, 0x5a, 0x57 } }
>    gSgi575AcpiTablesiFileGuid = { 0xc712719a, 0x0aaf, 0x438c, { 0x9c, 0xdd, 0x35, 0xab, 0x4d, 0x60, 0x20, 0x7d } }
>
>  [PcdsFeatureFlag.common]
>    # Set this PCD to TRUE to enable virtio support.
>    gArmSgiTokenSpaceGuid.PcdVirtioSupported|TRUE|BOOLEAN|0x00000001
> +
> +[Ppis]
> +  gHwConfigDtInfoPpiGuid     = { 0x6f606eb3, 0x9123, 0x4e15, { 0xa8, 0x9b, 0x0f, 0xac, 0x66, 0xef, 0xd0, 0x17 } }
> --
> 2.7.4
>