Re: [PATCH edk2-platforms 5/7] SbsaQemu: AcpiDxe: Create SSDT table at runtime

["Leif Lindholm" <leif@nuviainc.com>]

On Wed, Aug 19, 2020 at 20:00:03 +0530, Tanmay Jagdale wrote:
> - Add support to create SSDT table at runtime. Since SSDT
>   table is a data table, added a few helper macros to create
>   the AML entries.
> - Also added a function to calculate the length of Packages.
> 
> Signed-off-by: Tanmay Jagdale <tanmay.jagdale@linaro.org>
> ---
>  .../Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c | 144 ++++++++++++++++++
>  .../Include/IndustryStandard/SbsaQemuAcpi.h   |  29 ++++
>  2 files changed, 173 insertions(+)
> 
> diff --git a/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c b/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c
> index 569cda8b6474..d90ce0c2a718 100644
> --- a/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c
> +++ b/Silicon/Qemu/SbsaQemu/Drivers/SbsaQemuAcpiDxe/SbsaQemuAcpiDxe.c
> @@ -9,6 +9,7 @@
>  #include <IndustryStandard/Acpi.h>
>  #include <IndustryStandard/Acpi10.h>
>  #include <IndustryStandard/Acpi60.h>
> +#include <IndustryStandard/AcpiAml.h>
>  #include <IndustryStandard/SbsaQemuAcpi.h>
>  #include <Library/AcpiLib.h>
>  #include <Library/BaseMemoryLib.h>
> @@ -202,6 +203,144 @@ AddMadtTable (
>    return Status;
>  }
>  
> +/*
> + * Function to calculate the PkgLength field in ACPI tables
> + */
> +STATIC
> +UINT32
> +SetPkgLength (
> +  IN UINT8  *TablePtr,
> +  IN UINT32 Length
> +)
> +{
> +  UINT8  ByteCount;
> +  UINT8  *PkgLeadByte = TablePtr;
> +
> +  if (Length < 64) {
> +    *TablePtr = Length;
> +    return 1;
> +  }
> +
> +  // Set the LSB of Length in PkgLeadByte and advance Length
> +  *PkgLeadByte = Length & 0xF;
> +  Length = Length >> 4;
> +
> +  while (Length) {
> +    TablePtr++;
> +    *TablePtr = (Length & 0xFF);
> +    Length = (Length >> 8);
> +  }
> +
> +  // Calculate the number of bytes the Length field uses
> +  // and set the ByteCount field in PkgLeadByte.
> +  ByteCount = (TablePtr - PkgLeadByte) & 0xF;
> +  *PkgLeadByte |= (ByteCount << 6);
> +
> +  return ByteCount + 1;
> +}
> +
> +/*
> + * A function that adds SSDT ACPI table.
> + */
> +EFI_STATUS
> +AddSsdtTable (
> +  IN EFI_ACPI_TABLE_PROTOCOL   *AcpiTable
> +  )
> +{
> +  EFI_STATUS            Status;
> +  UINTN                 TableHandle;
> +  UINT32                TableSize;
> +  EFI_PHYSICAL_ADDRESS  PageAddress;
> +  UINT8                 *New;
> +  UINT32                CpuId;
> +  UINT32                Offset;
> +  UINT8                 ScopeOpName[] =  SBSAQEMU_ACPI_SCOPE_NAME;
> +  UINT32                NumCores = PcdGet32 (PcdCoreCount);
> +
> +  EFI_ACPI_DESCRIPTION_HEADER Header =
> +    SBSAQEMU_ACPI_HEADER (
> +      EFI_ACPI_6_0_SECONDARY_SYSTEM_DESCRIPTION_TABLE_SIGNATURE,
> +      EFI_ACPI_DESCRIPTION_HEADER,
> +      EFI_ACPI_6_0_SECONDARY_SYSTEM_DESCRIPTION_TABLE_REVISION);
> +
> +  SBSAQEMU_ACPI_CPU_DEVICE CpuDevice = {
> +    { AML_EXT_OP, AML_EXT_DEVICE_OP }, /* Device () */
> +    SBSAQEMU_ACPI_CPU_DEV_LEN,         /* Length */
> +    SBSAQEMU_ACPI_CPU_DEV_NAME,        /* Device Name "C000" */
> +    SBSAQEMU_ACPI_CPU_HID,             /* Name (HID, "ACPI0007") */
> +    SBSAQEMU_ACPI_CPU_UID,             /* Name (UID, 0) */
> +  };
> +
> +  // Calculate the new table size based on the number of cores
> +  TableSize = sizeof (EFI_ACPI_DESCRIPTION_HEADER) +
> +              SBSAQEMU_ACPI_SCOPE_OP_MAX_LENGTH + sizeof (ScopeOpName) +
> +	      (sizeof (CpuDevice) * NumCores);

Above line contains a tab. <edk2>/BaseTools/Scripts/PatchCheck.py will
find this (and some other issues) for you. Please run over whole set
and fix any reporeted issues before submitting v2.

/
    Leif

> +
> +  Status = gBS->AllocatePages (
> +                  AllocateAnyPages,
> +                  EfiACPIReclaimMemory,
> +                  EFI_SIZE_TO_PAGES (TableSize),
> +                  &PageAddress
> +                  );
> +  if (EFI_ERROR(Status)) {
> +    DEBUG((EFI_D_ERROR, "Failed to allocate pages for SSDT table\n"));
> +    return EFI_OUT_OF_RESOURCES;
> +  }
> +
> +  New = (UINT8 *)(UINTN) PageAddress;
> +  ZeroMem (New, TableSize);
> +
> +  // Add the ACPI Description table header
> +  CopyMem (New, &Header, sizeof (EFI_ACPI_DESCRIPTION_HEADER));
> +  ((EFI_ACPI_DESCRIPTION_HEADER*) New)->Length = TableSize;
> +  New += sizeof (EFI_ACPI_DESCRIPTION_HEADER);
> +
> +  // Insert the top level ScopeOp
> +  *New = AML_SCOPE_OP;
> +  New++;
> +  Offset = SetPkgLength (New,
> +             (TableSize - sizeof (EFI_ACPI_DESCRIPTION_HEADER) - 1));
> +  New += Offset;
> +  CopyMem (New, &ScopeOpName, sizeof (ScopeOpName));
> +  New += sizeof (ScopeOpName);
> +
> +  // Add new Device structures for the Cores
> +  for (CpuId = 0; CpuId < NumCores; CpuId++) {
> +    SBSAQEMU_ACPI_CPU_DEVICE *CpuDevicePtr;
> +    UINT8 CpuIdByte1, CpuIdByte2, CpuIdByte3;
> +
> +    CopyMem (New, &CpuDevice, sizeof (SBSAQEMU_ACPI_CPU_DEVICE));
> +    CpuDevicePtr = (SBSAQEMU_ACPI_CPU_DEVICE *) New;
> +
> +    CpuIdByte1 = CpuId & 0xF;
> +    CpuIdByte2 = (CpuId >> 4) & 0xF;
> +    CpuIdByte3 = (CpuId >> 8) & 0xF;
> +
> +    CpuDevicePtr->dev_name[1] = SBSAQEMU_ACPI_ITOA(CpuIdByte3);
> +    CpuDevicePtr->dev_name[2] = SBSAQEMU_ACPI_ITOA(CpuIdByte2);
> +    CpuDevicePtr->dev_name[3] = SBSAQEMU_ACPI_ITOA(CpuIdByte1);
> +
> +    CpuDevicePtr->uid[6] = CpuIdByte1 | CpuIdByte2;
> +    CpuDevicePtr->uid[7] = CpuIdByte3;
> +    New += sizeof (SBSAQEMU_ACPI_CPU_DEVICE);
> +  }
> +
> +  // Perform Checksum
> +  AcpiPlatformChecksum ((UINT8*) PageAddress, TableSize);
> +
> +  Status = AcpiTable->InstallAcpiTable (
> +                        AcpiTable,
> +                        (EFI_ACPI_COMMON_HEADER *)PageAddress,
> +                        TableSize,
> +                        &TableHandle
> +                        );
> +  if (EFI_ERROR(Status)) {
> +    DEBUG((EFI_D_ERROR, "Failed to install SSDT table\n"));
> +  }
> +
> +  return Status;
> +}
> +
>  EFI_STATUS
>  EFIAPI
>  InitializeSbsaQemuAcpiDxe (
> @@ -231,5 +370,10 @@ InitializeSbsaQemuAcpiDxe (
>       DEBUG((EFI_D_ERROR, "Failed to add MADT table\n"));
>    }
>  
> +  Status = AddSsdtTable (AcpiTable);
> +  if (EFI_ERROR(Status)) {
> +     DEBUG((EFI_D_ERROR, "Failed to add SSDT table\n"));
> +  }
> +
>    return EFI_SUCCESS;
>  }
> diff --git a/Silicon/Qemu/SbsaQemu/Include/IndustryStandard/SbsaQemuAcpi.h b/Silicon/Qemu/SbsaQemu/Include/IndustryStandard/SbsaQemuAcpi.h
> index 7a9a0061675f..60acc083ddbb 100644
> --- a/Silicon/Qemu/SbsaQemu/Include/IndustryStandard/SbsaQemuAcpi.h
> +++ b/Silicon/Qemu/SbsaQemu/Include/IndustryStandard/SbsaQemuAcpi.h
> @@ -43,4 +43,33 @@
>  #define SBSAQEMU_PCI_SEG0_BUSNUM_MIN     0x00
>  #define SBSAQEMU_PCI_SEG0_BUSNUM_MAX     0xFF
>  
> +#define SBSAQEMU_ACPI_SCOPE_OP_MAX_LENGTH 5
> +
> +#define SBSAQEMU_ACPI_SCOPE_NAME         { '_', 'S', 'B', '_' }
> +
> +#define SBSAQEMU_ACPI_CPU_DEV_LEN        0x1C
> +#define SBSAQEMU_ACPI_CPU_DEV_NAME       { 'C', '0', '0', '0' }
> +
> +// Macro to convert Integer to Character
> +#define SBSAQEMU_ACPI_ITOA(Byte)	(0x30 + (Byte > 9 ? (Byte + 1) : Byte))
> +
> +#define SBSAQEMU_ACPI_CPU_HID           {                                      \
> +  AML_NAME_OP, AML_NAME_CHAR__, 'H', 'I', 'D',                                 \
> +  AML_STRING_PREFIX, 'A', 'C', 'P', 'I', '0', '0', '0', '7',                   \
> +  AML_ZERO_OP                                                                  \
> +  }
> +
> +#define SBSAQEMU_ACPI_CPU_UID            {                                     \
> +   AML_NAME_OP, AML_NAME_CHAR__, 'U', 'I', 'D', AML_BYTE_PREFIX,               \
> +   AML_ZERO_OP, AML_ZERO_OP                                                    \
> +   }
> +
> +typedef struct {
> +  UINT8         device_header[2];
> +  UINT8         length;
> +  UINT8         dev_name[4];
> +  UINT8         hid[15];
> +  UINT8         uid[8];
> +} SBSAQEMU_ACPI_CPU_DEVICE;
> +
>  #endif
> -- 
> 2.28.0
>