DynamicTablesPkg/Library/Common/SsdtSerialPortFixupLib/Arm/ArmSsdtSerialPortFixupLib.c

/** @file
  SSDT Serial Port Fixup Library.

  Copyright (c) 2026, Arm Limited. All rights reserved.<BR>

  SPDX-License-Identifier: BSD-2-Clause-Patent

  @par Reference(s):
  - Arm Server Base Boot Requirements (SBBR), s4.2.1.8 "SPCR".
  - Microsoft Debug Port Table 2 (DBG2) Specification - December 10, 2015.
  - ACPI for Arm Components 1.0 - 2020
  - Arm Generic Interrupt Controller Architecture Specification,
    Issue H, January 2022.
    (https://developer.arm.com/documentation/ihi0069/)
**/
#include <Library/ArmLib.h>
#include <Library/ArmGicLib.h>
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>

#include <ArchCommonNameSpaceObjects.h>

/** Validate the Serial Port Architecture Information.

  @param [in]  SerialPortInfoTable    Table of CM_ARCH_COMMON_SERIAL_PORT_INFO.

  @retval EFI_SUCCESS             Success.
  @retval EFI_INVALID_PARAMETER   Invalid parameter.
**/
EFI_STATUS
EFIAPI
ArchValidateSerialPortInfo (
  IN  CONST CM_ARCH_COMMON_SERIAL_PORT_INFO  *SerialPortInfo
  )
{
  BOOLEAN  ValidInterrupt;

  if (SerialPortInfo == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  // If an interrupt is not wired to the serial port, the Configuration
  // Manager specifies the interrupt as 0.
  // Any other value must be within the SPI or extended SPI range.
  if ((SerialPortInfo->Interrupt != 0)) {
    ValidInterrupt = FALSE;

    if (ArmHasGicV5SystemRegisters ()) {
      if ((SerialPortInfo->Interrupt >= ARM_GICV5_ARCH_SPI_MIN) &&
          (SerialPortInfo->Interrupt <= ARM_GICV5_ARCH_SPI_MAX))
      {
        ValidInterrupt = TRUE;
      }
    } else {
      if (((SerialPortInfo->Interrupt >= ARM_GIC_ARCH_SPI_MIN) &&
           (SerialPortInfo->Interrupt <= ARM_GIC_ARCH_SPI_MAX)) ||
          ((SerialPortInfo->Interrupt >= ARM_GIC_ARCH_EXT_SPI_MIN) &&
           (SerialPortInfo->Interrupt <= ARM_GIC_ARCH_EXT_SPI_MAX)))
      {
        ValidInterrupt = TRUE;
      }
    }

    if (!ValidInterrupt) {
      DEBUG ((
        DEBUG_ERROR,
        "ERROR: Invalid UART port interrupt ID. Interrupt = %lu\n",
        SerialPortInfo->Interrupt
        ));
      return EFI_INVALID_PARAMETER;
    }
  }

  return EFI_SUCCESS;
}