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* [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true
@ 2023-04-27  6:13 paytonx.hsieh
  2023-04-27  6:17 ` Guo, Gua
  2023-04-27 17:36 ` [edk2-devel] " Benjamin Doron
  0 siblings, 2 replies; 6+ messages in thread
From: paytonx.hsieh @ 2023-04-27  6:13 UTC (permalink / raw)
  To: devel; +Cc: PaytonX Hsieh, Guo Dong, Ray Ni, Sean Rhodes, James Lu, Gua Guo

From: PaytonX Hsieh <paytonx.hsieh@intel.com>

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4427

1. Since UART speed is slower than CPU, BIOS need to check the write
   buffer is empty, to avoid overwrite the buffer content.
2. LPSS UART might disable MMIO space for Windows debug usage during
   ExitBootServices event. BIOS need to avoid access the MMIO space
   after ExitBootServices.

Cc: Guo Dong <guo.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Sean Rhodes <sean@starlabs.systems>
Cc: James Lu <james.lu@intel.com>
Cc: Gua Guo <gua.guo@intel.com>
Signed-off-by: PaytonX Hsieh <paytonx.hsieh@intel.com>
---
 .../BaseSerialPortLibHob.c                    |   7 +
 .../DxeBaseSerialPortLibHob.c                 | 903 ++++++++++++++++++
 .../DxeBaseSerialPortLibHob.inf               |  40 +
 UefiPayloadPkg/UefiPayloadPkg.dsc             |  11 +-
 4 files changed, 959 insertions(+), 2 deletions(-)
 create mode 100644 UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.c
 create mode 100644 UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf

diff --git a/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
index 8216195c62..3f844a42e1 100644
--- a/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
+++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
@@ -294,6 +294,13 @@ SerialPortWrite (
     BytesLeft  = NumberOfBytes;
 
     while (BytesLeft != 0) {
+      //
+      // Wait for the serial port to be ready, to make sure both the transmit FIFO
+      // and shift register empty.
+      //
+      while ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_TXRDY) == 0) {
+      }
+
       //
       // Fill the entire Tx FIFO
       //
diff --git a/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.c b/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.c
new file mode 100644
index 0000000000..5fcae9a699
--- /dev/null
+++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.c
@@ -0,0 +1,903 @@
+/** @file
+  UART Serial Port library functions.
+
+  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+#include <PiDxe.h>
+#include <Base.h>
+#include <Uefi.h>
+#include <Library/PcdLib.h>
+#include <Library/IoLib.h>
+#include <Library/BaseLib.h>
+#include <Library/HobLib.h>
+#include <Library/TimerLib.h>
+#include <Library/DebugLib.h>
+#include <Protocol/SerialIo.h>
+#include <UniversalPayload/SerialPortInfo.h>
+
+//
+// 16550 UART register offsets and bitfields
+//
+#define R_UART_RXBUF         0    // LCR_DLAB = 0
+#define R_UART_TXBUF         0    // LCR_DLAB = 0
+#define R_UART_BAUD_LOW      0    // LCR_DLAB = 1
+#define R_UART_BAUD_HIGH     1    // LCR_DLAB = 1
+#define R_UART_IER           1    // LCR_DLAB = 0
+#define R_UART_FCR           2
+#define   B_UART_FCR_FIFOE   BIT0
+#define   B_UART_FCR_FIFO64  BIT5
+#define R_UART_LCR           3
+#define   B_UART_LCR_DLAB    BIT7
+#define R_UART_MCR           4
+#define   B_UART_MCR_DTRC    BIT0
+#define   B_UART_MCR_RTS     BIT1
+#define R_UART_LSR           5
+#define   B_UART_LSR_RXRDY   BIT0
+#define   B_UART_LSR_TXRDY   BIT5
+#define   B_UART_LSR_TEMT    BIT6
+#define R_UART_MSR           6
+#define   B_UART_MSR_CTS     BIT4
+#define   B_UART_MSR_DSR     BIT5
+#define   B_UART_MSR_RI      BIT6
+#define   B_UART_MSR_DCD     BIT7
+
+#define MAX_SIZE  16
+
+typedef struct {
+  UINTN      BaseAddress;
+  BOOLEAN    UseMmio;
+  UINT32     BaudRate;
+  UINT8      RegisterStride;
+} UART_INFO;
+
+UART_INFO  mUartInfo[MAX_SIZE];
+UINT8      mUartCount = 0;
+EFI_EVENT  mBaseSerialPortLibHobExitBootServicesEvent;
+BOOLEAN    mBaseSerialPortLibHobAtRuntime = FALSE;
+
+/**
+  Reads an 8-bit register. If UseMmio is TRUE, then the value is read from
+  MMIO space. If UseMmio is FALSE, then the value is read from I/O space. The
+  parameter Offset is added to the base address of the register.
+
+  @param  Base             The base address register of UART device.
+  @param  Offset           The offset of the register to read.
+  @param  UseMmio          Check if value has to be read from MMIO space or IO space.
+  @param  RegisterStride   Number of bytes between registers in serial device.
+
+  @return The value read from the register.
+
+**/
+UINT8
+SerialPortReadRegister (
+  UINTN    Base,
+  UINTN    Offset,
+  BOOLEAN  UseMmio,
+  UINT8    RegisterStride
+  )
+{
+  if (UseMmio) {
+    return MmioRead8 (Base + Offset * RegisterStride);
+  } else {
+    return IoRead8 (Base + Offset * RegisterStride);
+  }
+}
+
+/**
+  Writes an 8-bit register.. If UseMmio is TRUE, then the value is written to
+  MMIO space. If UseMmio is FALSE, then the value is written to I/O space. The
+  parameter Offset is added to the base address of the registers.
+
+  @param  Base             The base address register of UART device.
+  @param  Offset           The offset of the register to write.
+  @param  Value            Value to be written.
+  @param  UseMmio          Check if value has to be written to MMIO space or IO space.
+  @param  RegisterStride   Number of bytes between registers in serial device.
+
+  @return The value written to the register.
+
+**/
+UINT8
+SerialPortWriteRegister (
+  UINTN    Base,
+  UINTN    Offset,
+  UINT8    Value,
+  BOOLEAN  UseMmio,
+  UINT8    RegisterStride
+  )
+{
+  if (UseMmio) {
+    return MmioWrite8 (Base + Offset * RegisterStride, Value);
+  } else {
+    return IoWrite8 (Base + Offset * RegisterStride, Value);
+  }
+}
+
+/**
+  Initialize the serial device hardware.
+
+  If no initialization is required, then return RETURN_SUCCESS.
+  If the serial device was successfully initialized, then return RETURN_SUCCESS.
+
+  @retval RETURN_SUCCESS        The serial device was initialized.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortInitialize (
+  VOID
+  )
+{
+  UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO  *SerialPortInfo;
+  EFI_HOB_GUID_TYPE                   *GuidHob;
+  UINTN                               SerialRegisterBase;
+  UINT8                               RegisterStride;
+  UINT32                              Divisor;
+  UINT32                              CurrentDivisor;
+  UINT32                              BaudRate;
+  BOOLEAN                             Initialized;
+  BOOLEAN                             MmioEnable;
+  UINT8                               Value;
+
+  if (mUartCount > 0) {
+    return RETURN_SUCCESS;
+  }
+
+  GuidHob = GetFirstGuidHob (&gUniversalPayloadSerialPortInfoGuid);
+  while (GuidHob != NULL) {
+    SerialPortInfo     = (UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO *)GET_GUID_HOB_DATA (GuidHob);
+    SerialRegisterBase = SerialPortInfo->RegisterBase;
+    MmioEnable         = SerialPortInfo->UseMmio;
+    BaudRate           = SerialPortInfo->BaudRate;
+    RegisterStride     = SerialPortInfo->RegisterStride;
+
+    if (SerialRegisterBase == 0) {
+      GuidHob = GET_NEXT_HOB (GuidHob);
+      GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);
+      continue;
+    }
+
+    mUartInfo[mUartCount].BaseAddress    = SerialRegisterBase;
+    mUartInfo[mUartCount].UseMmio        = MmioEnable;
+    mUartInfo[mUartCount].BaudRate       = BaudRate;
+    mUartInfo[mUartCount].RegisterStride = RegisterStride;
+    mUartCount++;
+
+    Divisor = PcdGet32 (PcdSerialClockRate) / (BaudRate * 16);
+    if ((PcdGet32 (PcdSerialClockRate) % (BaudRate * 16)) >= BaudRate * 8) {
+      Divisor++;
+    }
+
+    //
+    // See if the serial port is already initialized
+    //
+    Initialized = TRUE;
+    if ((SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) & 0x3F) != (PcdGet8 (PcdSerialLineControl) & 0x3F)) {
+      Initialized = FALSE;
+    }
+
+    Value = (UINT8)(SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) | B_UART_LCR_DLAB);
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, Value, MmioEnable, RegisterStride);
+    CurrentDivisor  =  SerialPortReadRegister (SerialRegisterBase, R_UART_BAUD_HIGH, MmioEnable, RegisterStride) << 8;
+    CurrentDivisor |= (UINT32)SerialPortReadRegister (SerialRegisterBase, R_UART_BAUD_LOW, MmioEnable, RegisterStride);
+    Value           = (UINT8)(SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) & ~B_UART_LCR_DLAB);
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, Value, MmioEnable, RegisterStride);
+    if (CurrentDivisor != Divisor) {
+      Initialized = FALSE;
+    }
+
+    if (Initialized) {
+      GuidHob = GET_NEXT_HOB (GuidHob);
+      GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);
+      continue;
+    }
+
+    //
+    // Configure baud rate
+    //
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, B_UART_LCR_DLAB, MmioEnable, RegisterStride);
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_BAUD_HIGH, (UINT8)(Divisor >> 8), MmioEnable, RegisterStride);
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_BAUD_LOW, (UINT8)(Divisor & 0xff), MmioEnable, RegisterStride);
+
+    //
+    // Clear DLAB and configure Data Bits, Parity, and Stop Bits.
+    // Strip reserved bits from PcdSerialLineControl
+    //
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, (UINT8)(PcdGet8 (PcdSerialLineControl) & 0x3F), MmioEnable, RegisterStride);
+
+    //
+    // Enable and reset FIFOs
+    // Strip reserved bits from PcdSerialFifoControl
+    //
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_FCR, 0x00, MmioEnable, RegisterStride);
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_FCR, (UINT8)(PcdGet8 (PcdSerialFifoControl) & (B_UART_FCR_FIFOE | B_UART_FCR_FIFO64)), MmioEnable, RegisterStride);
+
+    //
+    // Set FIFO Polled Mode by clearing IER after setting FCR
+    //
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_IER, 0x00, MmioEnable, RegisterStride);
+
+    //
+    // Put Modem Control Register(MCR) into its reset state of 0x00.
+    //
+    SerialPortWriteRegister (SerialRegisterBase, R_UART_MCR, 0x00, MmioEnable, RegisterStride);
+
+    GuidHob = GET_NEXT_HOB (GuidHob);
+    GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  Write data from buffer to serial device.
+
+  Writes NumberOfBytes data bytes from Buffer to the serial device.
+  The number of bytes actually written to the serial device is returned.
+  If the return value is less than NumberOfBytes, then the write operation failed.
+
+  If Buffer is NULL, then return 0.
+
+  If NumberOfBytes is zero, then return 0.
+
+  @param  Buffer           Pointer to the data buffer to be written.
+  @param  NumberOfBytes    Number of bytes to written to the serial device.
+
+  @retval 0                NumberOfBytes is 0.
+  @retval >0               The number of bytes written to the serial device.
+                           If this value is less than NumberOfBytes, then the write operation failed.
+
+**/
+UINTN
+EFIAPI
+SerialPortWrite (
+  IN UINT8  *Buffer,
+  IN UINTN  NumberOfBytes
+  )
+{
+  UINTN    BaseAddress;
+  BOOLEAN  UseMmio;
+  UINTN    BytesLeft;
+  UINTN    Index;
+  UINTN    FifoSize;
+  UINT8    *DataBuffer;
+  UINT8    Count;
+  UINT8    Stride;
+
+  if ((Buffer == NULL) || (NumberOfBytes == 0) || (mUartCount == 0)) {
+    return 0;
+  }
+
+  //
+  // Compute the maximum size of the Tx FIFO
+  //
+  FifoSize = 1;
+  if ((PcdGet8 (PcdSerialFifoControl) & B_UART_FCR_FIFOE) != 0) {
+    if ((PcdGet8 (PcdSerialFifoControl) & B_UART_FCR_FIFO64) == 0) {
+      FifoSize = 16;
+    } else {
+      FifoSize = PcdGet32 (PcdSerialExtendedTxFifoSize);
+    }
+  }
+
+  Count = 0;
+  while (Count < mUartCount) {
+    BaseAddress = mUartInfo[Count].BaseAddress;
+    UseMmio     = mUartInfo[Count].UseMmio;
+    Stride      = mUartInfo[Count].RegisterStride;
+
+    if (UseMmio && mBaseSerialPortLibHobAtRuntime) {
+      Count++;
+      continue;
+    }
+
+    if (BaseAddress == 0) {
+      Count++;
+      continue;
+    }
+
+    DataBuffer = Buffer;
+    BytesLeft  = NumberOfBytes;
+
+    while (BytesLeft != 0) {
+      //
+      // Wait for the serial port to be ready, to make sure both the transmit FIFO
+      // and shift register empty.
+      //
+      while ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_TXRDY) == 0) {
+      }
+
+      //
+      // Fill the entire Tx FIFO
+      //
+      for (Index = 0; Index < FifoSize && BytesLeft != 0; Index++, BytesLeft--, DataBuffer++) {
+        //
+        // Write byte to the transmit buffer.
+        //
+        SerialPortWriteRegister (BaseAddress, R_UART_TXBUF, *DataBuffer, UseMmio, Stride);
+      }
+
+      MicroSecondDelay (20);
+    }
+
+    Count++;
+  }
+
+  return NumberOfBytes;
+}
+
+/**
+  Reads data from a serial device into a buffer.
+
+  @param  Buffer           Pointer to the data buffer to store the data read from the serial device.
+  @param  NumberOfBytes    Number of bytes to read from the serial device.
+
+  @retval 0                NumberOfBytes is 0.
+  @retval >0               The number of bytes read from the serial device.
+                           If this value is less than NumberOfBytes, then the read operation failed.
+
+**/
+UINTN
+EFIAPI
+SerialPortRead (
+  OUT UINT8  *Buffer,
+  IN  UINTN  NumberOfBytes
+  )
+{
+  UINTN    BaseAddress;
+  BOOLEAN  UseMmio;
+  BOOLEAN  IsNextPort;
+  UINT8    *DataBuffer;
+  UINTN    BytesLeft;
+  UINTN    Result;
+  UINT8    Mcr;
+  UINT8    Count;
+  UINT8    Stride;
+
+  if (Buffer == NULL) {
+    return 0;
+  }
+
+  Count = 0;
+  while (Count < mUartCount) {
+    BaseAddress = mUartInfo[Count].BaseAddress;
+    UseMmio     = mUartInfo[Count].UseMmio;
+    Stride      = mUartInfo[Count].RegisterStride;
+
+    if (BaseAddress == 0) {
+      Count++;
+      continue;
+    }
+
+    DataBuffer = Buffer;
+    BytesLeft  = NumberOfBytes;
+    IsNextPort = FALSE;
+
+    Mcr = (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) & ~B_UART_MCR_RTS);
+
+    for (Result = 0; BytesLeft-- != 0; Result++, DataBuffer++) {
+      //
+      // Wait for the serial port to have some data.
+      //
+      while ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_RXRDY) == 0) {
+        if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+          //
+          // Set RTS to let the peer send some data
+          //
+          SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(Mcr | B_UART_MCR_RTS), UseMmio, Stride);
+        }
+
+        IsNextPort = TRUE;
+        break;
+      }
+
+      if (IsNextPort) {
+        break;
+      }
+
+      if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+        //
+        // Clear RTS to prevent peer from sending data
+        //
+        SerialPortWriteRegister (BaseAddress, R_UART_MCR, Mcr, UseMmio, Stride);
+      }
+
+      //
+      // Read byte from the receive buffer.
+      //
+      *DataBuffer = SerialPortReadRegister (BaseAddress, R_UART_RXBUF, UseMmio, Stride);
+    }
+
+    if ((!IsNextPort) && (*(--DataBuffer) != '\0')) {
+      return Result;
+    }
+
+    Count++;
+  }
+
+  return Result;
+}
+
+/**
+  Polls a serial device to see if there is any data waiting to be read.
+
+  Polls a serial device to see if there is any data waiting to be read.
+  If there is data waiting to be read from the serial device, then TRUE is returned.
+  If there is no data waiting to be read from the serial device, then FALSE is returned.
+
+  @retval TRUE             Data is waiting to be read from the serial device.
+  @retval FALSE            There is no data waiting to be read from the serial device.
+
+**/
+BOOLEAN
+EFIAPI
+SerialPortPoll (
+  VOID
+  )
+{
+  UINTN    BaseAddress;
+  BOOLEAN  UseMmio;
+  UINT8    Stride;
+  UINT8    Count;
+  BOOLEAN  IsDataReady;
+
+  Count = 0;
+  while (Count < mUartCount) {
+    BaseAddress = mUartInfo[Count].BaseAddress;
+    UseMmio     = mUartInfo[Count].UseMmio;
+    Stride      = mUartInfo[Count].RegisterStride;
+
+    if (BaseAddress == 0) {
+      Count++;
+      continue;
+    }
+
+    IsDataReady = FALSE;
+
+    //
+    // Read the serial port status
+    //
+    if ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_RXRDY) != 0) {
+      if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+        //
+        // Clear RTS to prevent peer from sending data
+        //
+        SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) & ~B_UART_MCR_RTS), UseMmio, Stride);
+      }
+
+      IsDataReady = TRUE;
+    }
+
+    if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+      //
+      // Set RTS to let the peer send some data
+      //
+      SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) | B_UART_MCR_RTS), UseMmio, Stride);
+    }
+
+    if (IsDataReady) {
+      return IsDataReady;
+    }
+
+    Count++;
+  }
+
+  return IsDataReady;
+}
+
+/**
+  Sets the control bits on a serial device.
+
+  @param Control                Sets the bits of Control that are settable.
+
+  @retval RETURN_SUCCESS        The new control bits were set on the serial device.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortSetControl (
+  IN UINT32  Control
+  )
+{
+  UINTN    BaseAddress;
+  BOOLEAN  UseMmio;
+  UINT8    Mcr;
+  UINT8    Count;
+  UINT8    Stride;
+
+  Count = 0;
+  while (Count < mUartCount) {
+    BaseAddress = mUartInfo[Count].BaseAddress;
+    UseMmio     = mUartInfo[Count].UseMmio;
+    Stride      = mUartInfo[Count].RegisterStride;
+
+    if (BaseAddress == 0) {
+      Count++;
+      continue;
+    }
+
+    //
+    // First determine the parameter is invalid.
+    //
+    if ((Control & (~(EFI_SERIAL_REQUEST_TO_SEND | EFI_SERIAL_DATA_TERMINAL_READY |
+                      EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE))) != 0)
+    {
+      Count++;
+      continue;
+    }
+
+    //
+    // Read the Modem Control Register.
+    //
+    Mcr  = SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride);
+    Mcr &= (~(B_UART_MCR_DTRC | B_UART_MCR_RTS));
+
+    if ((Control & EFI_SERIAL_DATA_TERMINAL_READY) == EFI_SERIAL_DATA_TERMINAL_READY) {
+      Mcr |= B_UART_MCR_DTRC;
+    }
+
+    if ((Control & EFI_SERIAL_REQUEST_TO_SEND) == EFI_SERIAL_REQUEST_TO_SEND) {
+      Mcr |= B_UART_MCR_RTS;
+    }
+
+    //
+    // Write the Modem Control Register.
+    //
+    SerialPortWriteRegister (BaseAddress, R_UART_MCR, Mcr, UseMmio, Stride);
+    Count++;
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  Retrieve the status of the control bits on a serial device.
+
+  @param Control                A pointer to return the current control signals from the serial device.
+
+  @retval RETURN_SUCCESS        The control bits were read from the serial device.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortGetControl (
+  OUT UINT32  *Control
+  )
+{
+  UINTN    BaseAddress;
+  BOOLEAN  UseMmio;
+  UINT8    Msr;
+  UINT8    Mcr;
+  UINT8    Lsr;
+  UINT8    Count;
+  UINT8    Stride;
+
+  Count = 0;
+  while (Count < mUartCount) {
+    BaseAddress = mUartInfo[Count].BaseAddress;
+    UseMmio     = mUartInfo[Count].UseMmio;
+    Stride      = mUartInfo[Count].RegisterStride;
+
+    if (BaseAddress == 0) {
+      Count++;
+      continue;
+    }
+
+    *Control = 0;
+
+    //
+    // Read the Modem Status Register.
+    //
+    Msr = SerialPortReadRegister (BaseAddress, R_UART_MSR, UseMmio, Stride);
+
+    if ((Msr & B_UART_MSR_CTS) == B_UART_MSR_CTS) {
+      *Control |= EFI_SERIAL_CLEAR_TO_SEND;
+    }
+
+    if ((Msr & B_UART_MSR_DSR) == B_UART_MSR_DSR) {
+      *Control |= EFI_SERIAL_DATA_SET_READY;
+    }
+
+    if ((Msr & B_UART_MSR_RI) == B_UART_MSR_RI) {
+      *Control |= EFI_SERIAL_RING_INDICATE;
+    }
+
+    if ((Msr & B_UART_MSR_DCD) == B_UART_MSR_DCD) {
+      *Control |= EFI_SERIAL_CARRIER_DETECT;
+    }
+
+    //
+    // Read the Modem Control Register.
+    //
+    Mcr = SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride);
+
+    if ((Mcr & B_UART_MCR_DTRC) == B_UART_MCR_DTRC) {
+      *Control |= EFI_SERIAL_DATA_TERMINAL_READY;
+    }
+
+    if ((Mcr & B_UART_MCR_RTS) == B_UART_MCR_RTS) {
+      *Control |= EFI_SERIAL_REQUEST_TO_SEND;
+    }
+
+    if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {
+      *Control |= EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE;
+    }
+
+    //
+    // Read the Line Status Register.
+    //
+    Lsr = SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride);
+
+    if ((Lsr & (B_UART_LSR_TEMT | B_UART_LSR_TXRDY)) == (B_UART_LSR_TEMT | B_UART_LSR_TXRDY)) {
+      *Control |= EFI_SERIAL_OUTPUT_BUFFER_EMPTY;
+    }
+
+    if ((Lsr & B_UART_LSR_RXRDY) == 0) {
+      *Control |= EFI_SERIAL_INPUT_BUFFER_EMPTY;
+    }
+
+    if ((((*Control & EFI_SERIAL_OUTPUT_BUFFER_EMPTY) == EFI_SERIAL_OUTPUT_BUFFER_EMPTY) &&
+         ((*Control & EFI_SERIAL_INPUT_BUFFER_EMPTY) != EFI_SERIAL_INPUT_BUFFER_EMPTY)) ||
+        ((*Control & (EFI_SERIAL_DATA_SET_READY | EFI_SERIAL_CLEAR_TO_SEND |
+                      EFI_SERIAL_CARRIER_DETECT)) == (EFI_SERIAL_DATA_SET_READY | EFI_SERIAL_CLEAR_TO_SEND |
+                                                      EFI_SERIAL_CARRIER_DETECT)))
+    {
+      return RETURN_SUCCESS;
+    }
+
+    Count++;
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  Sets the baud rate, receive FIFO depth, transmit/receice time out, parity,
+  data bits, and stop bits on a serial device.
+
+  @param BaudRate           The requested baud rate. A BaudRate value of 0 will use the
+                            device's default interface speed.
+                            On output, the value actually set.
+  @param ReveiveFifoDepth   The requested depth of the FIFO on the receive side of the
+                            serial interface. A ReceiveFifoDepth value of 0 will use
+                            the device's default FIFO depth.
+                            On output, the value actually set.
+  @param Timeout            The requested time out for a single character in microseconds.
+                            This timeout applies to both the transmit and receive side of the
+                            interface. A Timeout value of 0 will use the device's default time
+                            out value.
+                            On output, the value actually set.
+  @param Parity             The type of parity to use on this serial device. A Parity value of
+                            DefaultParity will use the device's default parity value.
+                            On output, the value actually set.
+  @param DataBits           The number of data bits to use on the serial device. A DataBits
+                            vaule of 0 will use the device's default data bit setting.
+                            On output, the value actually set.
+  @param StopBits           The number of stop bits to use on this serial device. A StopBits
+                            value of DefaultStopBits will use the device's default number of
+                            stop bits.
+                            On output, the value actually set.
+
+  @retval RETURN_SUCCESS            The new attributes were set on the serial device.
+
+**/
+RETURN_STATUS
+EFIAPI
+SerialPortSetAttributes (
+  IN OUT UINT64              *BaudRate,
+  IN OUT UINT32              *ReceiveFifoDepth,
+  IN OUT UINT32              *Timeout,
+  IN OUT EFI_PARITY_TYPE     *Parity,
+  IN OUT UINT8               *DataBits,
+  IN OUT EFI_STOP_BITS_TYPE  *StopBits
+  )
+{
+  UINTN    BaseAddress;
+  BOOLEAN  UseMmio;
+  UINT32   SerialBaudRate;
+  UINTN    Divisor;
+  UINT8    Lcr;
+  UINT8    LcrData;
+  UINT8    LcrParity;
+  UINT8    LcrStop;
+  UINT8    Count;
+  UINT8    Stride;
+
+  Count = 0;
+  while (Count < mUartCount) {
+    BaseAddress = mUartInfo[Count].BaseAddress;
+    UseMmio     = mUartInfo[Count].UseMmio;
+    Stride      = mUartInfo[Count].RegisterStride;
+
+    if (BaseAddress == 0) {
+      Count++;
+      continue;
+    }
+
+    //
+    // Check for default settings and fill in actual values.
+    //
+    if (*BaudRate == 0) {
+      *BaudRate = mUartInfo[Count].BaudRate;
+    }
+
+    SerialBaudRate = (UINT32)*BaudRate;
+
+    if (*DataBits == 0) {
+      LcrData   = (UINT8)(PcdGet8 (PcdSerialLineControl) & 0x3);
+      *DataBits = LcrData + 5;
+    } else {
+      if ((*DataBits < 5) || (*DataBits > 8)) {
+        Count++;
+        continue;
+      }
+
+      //
+      // Map 5..8 to 0..3
+      //
+      LcrData = (UINT8)(*DataBits - (UINT8)5);
+    }
+
+    if (*Parity == DefaultParity) {
+      LcrParity = (UINT8)((PcdGet8 (PcdSerialLineControl) >> 3) & 0x7);
+      switch (LcrParity) {
+        case 0:
+          *Parity = NoParity;
+          break;
+
+        case 3:
+          *Parity = EvenParity;
+          break;
+
+        case 1:
+          *Parity = OddParity;
+          break;
+
+        case 7:
+          *Parity = SpaceParity;
+          break;
+
+        case 5:
+          *Parity = MarkParity;
+          break;
+
+        default:
+          break;
+      }
+    } else {
+      switch (*Parity) {
+        case NoParity:
+          LcrParity = 0;
+          break;
+
+        case EvenParity:
+          LcrParity = 3;
+          break;
+
+        case OddParity:
+          LcrParity = 1;
+          break;
+
+        case SpaceParity:
+          LcrParity = 7;
+          break;
+
+        case MarkParity:
+          LcrParity = 5;
+          break;
+
+        default:
+          Count++;
+          continue;
+      }
+    }
+
+    if (*StopBits == DefaultStopBits) {
+      LcrStop = (UINT8)((PcdGet8 (PcdSerialLineControl) >> 2) & 0x1);
+      switch (LcrStop) {
+        case 0:
+          *StopBits = OneStopBit;
+          break;
+
+        case 1:
+          if (*DataBits == 5) {
+            *StopBits = OneFiveStopBits;
+          } else {
+            *StopBits = TwoStopBits;
+          }
+
+          break;
+
+        default:
+          break;
+      }
+    } else {
+      switch (*StopBits) {
+        case OneStopBit:
+          LcrStop = 0;
+          break;
+
+        case OneFiveStopBits:
+        case TwoStopBits:
+          LcrStop = 1;
+          break;
+
+        default:
+          Count++;
+          continue;
+      }
+    }
+
+    //
+    // Calculate divisor for baud generator
+    //    Ref_Clk_Rate / Baud_Rate / 16
+    //
+    Divisor = PcdGet32 (PcdSerialClockRate) / (SerialBaudRate * 16);
+    if ((PcdGet32 (PcdSerialClockRate) % (SerialBaudRate * 16)) >= SerialBaudRate * 8) {
+      Divisor++;
+    }
+
+    //
+    // Configure baud rate
+    //
+    SerialPortWriteRegister (BaseAddress, R_UART_LCR, B_UART_LCR_DLAB, UseMmio, Stride);
+    SerialPortWriteRegister (BaseAddress, R_UART_BAUD_HIGH, (UINT8)(Divisor >> 8), UseMmio, Stride);
+    SerialPortWriteRegister (BaseAddress, R_UART_BAUD_LOW, (UINT8)(Divisor & 0xff), UseMmio, Stride);
+
+    //
+    // Clear DLAB and configure Data Bits, Parity, and Stop Bits.
+    // Strip reserved bits from line control value
+    //
+    Lcr = (UINT8)((LcrParity << 3) | (LcrStop << 2) | LcrData);
+    SerialPortWriteRegister (BaseAddress, R_UART_LCR, (UINT8)(Lcr & 0x3F), UseMmio, Stride);
+    Count++;
+  }
+
+  return RETURN_SUCCESS;
+}
+
+/**
+  Set mSerialIoUartLibAtRuntime flag as TRUE after ExitBootServices.
+
+  @param[in]  Event   The Event that is being processed.
+  @param[in]  Context The Event Context.
+
+**/
+STATIC
+VOID
+EFIAPI
+BaseSerialPortLibHobExitBootServicesEvent (
+  IN EFI_EVENT  Event,
+  IN VOID       *Context
+  )
+{
+  mBaseSerialPortLibHobAtRuntime = TRUE;
+}
+
+/**
+  The constructor function registers a callback for the ExitBootServices event.
+
+  @param[in]  ImageHandle   The firmware allocated handle for the EFI image.
+  @param[in]  SystemTable   A pointer to the EFI System Table.
+
+  @retval EFI_SUCCESS   The operation completed successfully.
+  @retval other         Either the serial port failed to initialize or the
+                        ExitBootServices event callback registration failed.
+**/
+EFI_STATUS
+EFIAPI
+DxeBaseSerialPortLibHobConstructor (
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  return SystemTable->BootServices->CreateEvent (
+                                      EVT_SIGNAL_EXIT_BOOT_SERVICES,
+                                      TPL_NOTIFY,
+                                      BaseSerialPortLibHobExitBootServicesEvent,
+                                      NULL,
+                                      &mBaseSerialPortLibHobExitBootServicesEvent
+                                      );
+}
diff --git a/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf b/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf
new file mode 100644
index 0000000000..e16a9a4a83
--- /dev/null
+++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf
@@ -0,0 +1,40 @@
+## @file
+#  SerialPortLib instance for UART information retrieved from bootloader.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = DxeBaseSerialPortLibHob
+  FILE_GUID                      = c8def0c5-48e7-45b8-8299-485ea2e63b2c
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = SerialPortLib|DXE_CORE DXE_DRIVER DXE_RUNTIME_DRIVER DXE_SMM_DRIVER UEFI_APPLICATION UEFI_DRIVER
+  CONSTRUCTOR                    = DxeBaseSerialPortLibHobConstructor
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+  PcdLib
+  IoLib
+  HobLib
+  TimerLib
+
+[Sources]
+  DxeBaseSerialPortLibHob.c
+
+[Pcd]
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialLineControl
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialFifoControl
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialClockRate
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialExtendedTxFifoSize
+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialUseHardwareFlowControl
+
+[Guids]
+  gUniversalPayloadSerialPortInfoGuid
diff --git a/UefiPayloadPkg/UefiPayloadPkg.dsc b/UefiPayloadPkg/UefiPayloadPkg.dsc
index 9847f189ff..998d222909 100644
--- a/UefiPayloadPkg/UefiPayloadPkg.dsc
+++ b/UefiPayloadPkg/UefiPayloadPkg.dsc
@@ -256,7 +256,11 @@
   SerialPortLib|UefiPayloadPkg/Library/CbSerialPortLib/CbSerialPortLib.inf
   PlatformHookLib|MdeModulePkg/Library/BasePlatformHookLibNull/BasePlatformHookLibNull.inf
 !else
-  SerialPortLib|MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf
+  !if $(MULTIPLE_DEBUG_PORT_SUPPORT) == TRUE
+    SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf
+  !else
+    SerialPortLib|MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf
+  !endif
   PlatformHookLib|UefiPayloadPkg/Library/PlatformHookLib/PlatformHookLib.inf
 !endif
   PlatformBootManagerLib|UefiPayloadPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf
@@ -313,6 +317,9 @@
   PcdLib|MdePkg/Library/BasePcdLibNull/BasePcdLibNull.inf
   DxeHobListLib|UefiPayloadPkg/Library/DxeHobListLibNull/DxeHobListLibNull.inf
   DebugLib|MdePkg/Library/BaseDebugLibSerialPort/BaseDebugLibSerialPort.inf
+!if $(MULTIPLE_DEBUG_PORT_SUPPORT) == TRUE
+  SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf
+!endif
 
 [LibraryClasses.common.DXE_CORE]
   DxeHobListLib|UefiPayloadPkg/Library/DxeHobListLibNull/DxeHobListLibNull.inf
@@ -617,7 +624,7 @@
     <LibraryClasses>
       !if $(MULTIPLE_DEBUG_PORT_SUPPORT) == TRUE
         DebugLib|MdePkg/Library/BaseDebugLibSerialPort/BaseDebugLibSerialPort.inf
-        SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf
+        SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf
       !endif
       NULL|MdeModulePkg/Library/LzmaCustomDecompressLib/LzmaCustomDecompressLib.inf
   }
-- 
2.39.2.windows.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true
  2023-04-27  6:13 [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true paytonx.hsieh
@ 2023-04-27  6:17 ` Guo, Gua
  2023-04-27 17:36 ` [edk2-devel] " Benjamin Doron
  1 sibling, 0 replies; 6+ messages in thread
From: Guo, Gua @ 2023-04-27  6:17 UTC (permalink / raw)
  To: Hsieh, PaytonX, devel@edk2.groups.io
  Cc: Dong, Guo, Ni, Ray, Rhodes, Sean, Lu, James

Reviewed-by: Gua Guo <gua.guo@intel.com>

-----Original Message-----
From: Hsieh, PaytonX <paytonx.hsieh@intel.com> 
Sent: Thursday, April 27, 2023 2:14 PM
To: devel@edk2.groups.io
Cc: Hsieh, PaytonX <paytonx.hsieh@intel.com>; Dong, Guo <guo.dong@intel.com>; Ni, Ray <ray.ni@intel.com>; Rhodes, Sean <sean@starlabs.systems>; Lu, James <james.lu@intel.com>; Guo, Gua <gua.guo@intel.com>
Subject: [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true

From: PaytonX Hsieh <paytonx.hsieh@intel.com>

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4427

1. Since UART speed is slower than CPU, BIOS need to check the write
   buffer is empty, to avoid overwrite the buffer content.
2. LPSS UART might disable MMIO space for Windows debug usage during
   ExitBootServices event. BIOS need to avoid access the MMIO space
   after ExitBootServices.

Cc: Guo Dong <guo.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Sean Rhodes <sean@starlabs.systems>
Cc: James Lu <james.lu@intel.com>
Cc: Gua Guo <gua.guo@intel.com>
Signed-off-by: PaytonX Hsieh <paytonx.hsieh@intel.com>
---
 .../BaseSerialPortLibHob.c                    |   7 +
 .../DxeBaseSerialPortLibHob.c                 | 903 ++++++++++++++++++
 .../DxeBaseSerialPortLibHob.inf               |  40 +
 UefiPayloadPkg/UefiPayloadPkg.dsc             |  11 +-
 4 files changed, 959 insertions(+), 2 deletions(-)  create mode 100644 UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.c
 create mode 100644 UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf

diff --git a/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
index 8216195c62..3f844a42e1 100644
--- a/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
+++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.c
@@ -294,6 +294,13 @@ SerialPortWrite (
     BytesLeft  = NumberOfBytes;      while (BytesLeft != 0) {+      //+      // Wait for the serial port to be ready, to make sure both the transmit FIFO+      // and shift register empty.+      //+      while ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_TXRDY) == 0) {+      }+       //       // Fill the entire Tx FIFO       //diff --git a/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.c b/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.c
new file mode 100644
index 0000000000..5fcae9a699
--- /dev/null
+++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHo
+++ b.c
@@ -0,0 +1,903 @@
+/** @file+  UART Serial Port library functions.++  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>+  SPDX-License-Identifier: BSD-2-Clause-Patent++**/+#include <PiDxe.h>+#include <Base.h>+#include <Uefi.h>+#include <Library/PcdLib.h>+#include <Library/IoLib.h>+#include <Library/BaseLib.h>+#include <Library/HobLib.h>+#include <Library/TimerLib.h>+#include <Library/DebugLib.h>+#include <Protocol/SerialIo.h>+#include <UniversalPayload/SerialPortInfo.h>++//+// 16550 UART register offsets and bitfields+//+#define R_UART_RXBUF         0    // LCR_DLAB = 0+#define R_UART_TXBUF         0    // LCR_DLAB = 0+#define R_UART_BAUD_LOW      0    // LCR_DLAB = 1+#define R_UART_BAUD_HIGH     1    // LCR_DLAB = 1+#define R_UART_IER           1    // LCR_DLAB = 0+#define R_UART_FCR           2+#define   B_UART_FCR_FIFOE   BIT0+#define   B_UART_FCR_FIFO64  BIT5+#define R_UART_LCR           3+#define   B_UART_LCR_DLAB    BIT7+#define R_UART_MCR           4+#define   B_UART_MCR_DTRC    BIT0+#define   B_UART_MCR_RTS     BIT1+#define R_UART_LSR           5+#define   B_UART_LSR_RXRDY   BIT0+#define   B_UART_LSR_TXRDY   BIT5+#define   B_UART_LSR_TEMT    BIT6+#define R_UART_MSR           6+#define   B_UART_MSR_CTS     BIT4+#define   B_UART_MSR_DSR     BIT5+#define   B_UART_MSR_RI      BIT6+#define   B_UART_MSR_DCD     BIT7++#define MAX_SIZE  16++typedef struct {+  UINTN      BaseAddress;+  BOOLEAN    UseMmio;+  UINT32     BaudRate;+  UINT8      RegisterStride;+} UART_INFO;++UART_INFO  mUartInfo[MAX_SIZE];+UINT8      mUartCount = 0;+EFI_EVENT  mBaseSerialPortLibHobExitBootServicesEvent;+BOOLEAN    mBaseSerialPortLibHobAtRuntime = FALSE;++/**+  Reads an 8-bit register. If UseMmio is TRUE, then the value is read from+  MMIO space. If UseMmio is FALSE, then the value is read from I/O space. The+  parameter Offset is added to the base address of the register.++  @param  Base             The base address register of UART device.+  @param  Offset           The offset of the register to read.+  @param  UseMmio          Check if value has to be read from MMIO space or IO space.+  @param  RegisterStride   Number of bytes between registers in serial device.++  @return The value read from the register.++**/+UINT8+SerialPortReadRegister (+  UINTN    Base,+  UINTN    Offset,+  BOOLEAN  UseMmio,+  UINT8    RegisterStride+  )+{+  if (UseMmio) {+    return MmioRead8 (Base + Offset * RegisterStride);+  } else {+    return IoRead8 (Base + Offset * RegisterStride);+  }+}++/**+  Writes an 8-bit register.. If UseMmio is TRUE, then the value is written to+  MMIO space. If UseMmio is FALSE, then the value is written to I/O space. The+  parameter Offset is added to the base address of the registers.++  @param  Base             The base address register of UART device.+  @param  Offset           The offset of the register to write.+  @param  Value            Value to be written.+  @param  UseMmio          Check if value has to be written to MMIO space or IO space.+  @param  RegisterStride   Number of bytes between registers in serial device.++  @return The value written to the register.++**/+UINT8+SerialPortWriteRegister (+  UINTN    Base,+  UINTN    Offset,+  UINT8    Value,+  BOOLEAN  UseMmio,+  UINT8    RegisterStride+  )+{+  if (UseMmio) {+    return MmioWrite8 (Base + Offset * RegisterStride, Value);+  } else {+    return IoWrite8 (Base + Offset * RegisterStride, Value);+  }+}++/**+  Initialize the serial device hardware.++  If no initialization is required, then return RETURN_SUCCESS.+  If the serial device was successfully initialized, then return RETURN_SUCCESS.++  @retval RETURN_SUCCESS        The serial device was initialized.++**/+RETURN_STATUS+EFIAPI+SerialPortInitialize (+  VOID+  )+{+  UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO  *SerialPortInfo;+  EFI_HOB_GUID_TYPE                   *GuidHob;+  UINTN                               SerialRegisterBase;+  UINT8                               RegisterStride;+  UINT32                              Divisor;+  UINT32                              CurrentDivisor;+  UINT32                              BaudRate;+  BOOLEAN                             Initialized;+  BOOLEAN                             MmioEnable;+  UINT8                               Value;++  if (mUartCount > 0) {+    return RETURN_SUCCESS;+  }++  GuidHob = GetFirstGuidHob (&gUniversalPayloadSerialPortInfoGuid);+  while (GuidHob != NULL) {+    SerialPortInfo     = (UNIVERSAL_PAYLOAD_SERIAL_PORT_INFO *)GET_GUID_HOB_DATA (GuidHob);+    SerialRegisterBase = SerialPortInfo->RegisterBase;+    MmioEnable         = SerialPortInfo->UseMmio;+    BaudRate           = SerialPortInfo->BaudRate;+    RegisterStride     = SerialPortInfo->RegisterStride;++    if (SerialRegisterBase == 0) {+      GuidHob = GET_NEXT_HOB (GuidHob);+      GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);+      continue;+    }++    mUartInfo[mUartCount].BaseAddress    = SerialRegisterBase;+    mUartInfo[mUartCount].UseMmio        = MmioEnable;+    mUartInfo[mUartCount].BaudRate       = BaudRate;+    mUartInfo[mUartCount].RegisterStride = RegisterStride;+    mUartCount++;++    Divisor = PcdGet32 (PcdSerialClockRate) / (BaudRate * 16);+    if ((PcdGet32 (PcdSerialClockRate) % (BaudRate * 16)) >= BaudRate * 8) {+      Divisor++;+    }++    //+    // See if the serial port is already initialized+    //+    Initialized = TRUE;+    if ((SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) & 0x3F) != (PcdGet8 (PcdSerialLineControl) & 0x3F)) {+      Initialized = FALSE;+    }++    Value = (UINT8)(SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) | B_UART_LCR_DLAB);+    SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, Value, MmioEnable, RegisterStride);+    CurrentDivisor  =  SerialPortReadRegister (SerialRegisterBase, R_UART_BAUD_HIGH, MmioEnable, RegisterStride) << 8;+    CurrentDivisor |= (UINT32)SerialPortReadRegister (SerialRegisterBase, R_UART_BAUD_LOW, MmioEnable, RegisterStride);+    Value           = (UINT8)(SerialPortReadRegister (SerialRegisterBase, R_UART_LCR, MmioEnable, RegisterStride) & ~B_UART_LCR_DLAB);+    SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, Value, MmioEnable, RegisterStride);+    if (CurrentDivisor != Divisor) {+      Initialized = FALSE;+    }++    if (Initialized) {+      GuidHob = GET_NEXT_HOB (GuidHob);+      GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);+      continue;+    }++    //+    // Configure baud rate+    //+    SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, B_UART_LCR_DLAB, MmioEnable, RegisterStride);+    SerialPortWriteRegister (SerialRegisterBase, R_UART_BAUD_HIGH, (UINT8)(Divisor >> 8), MmioEnable, RegisterStride);+    SerialPortWriteRegister (SerialRegisterBase, R_UART_BAUD_LOW, (UINT8)(Divisor & 0xff), MmioEnable, RegisterStride);++    //+    // Clear DLAB and configure Data Bits, Parity, and Stop Bits.+    // Strip reserved bits from PcdSerialLineControl+    //+    SerialPortWriteRegister (SerialRegisterBase, R_UART_LCR, (UINT8)(PcdGet8 (PcdSerialLineControl) & 0x3F), MmioEnable, RegisterStride);++    //+    // Enable and reset FIFOs+    // Strip reserved bits from PcdSerialFifoControl+    //+    SerialPortWriteRegister (SerialRegisterBase, R_UART_FCR, 0x00, MmioEnable, RegisterStride);+    SerialPortWriteRegister (SerialRegisterBase, R_UART_FCR, (UINT8)(PcdGet8 (PcdSerialFifoControl) & (B_UART_FCR_FIFOE | B_UART_FCR_FIFO64)), MmioEnable, RegisterStride);++    //+    // Set FIFO Polled Mode by clearing IER after setting FCR+    //+    SerialPortWriteRegister (SerialRegisterBase, R_UART_IER, 0x00, MmioEnable, RegisterStride);++    //+    // Put Modem Control Register(MCR) into its reset state of 0x00.+    //+    SerialPortWriteRegister (SerialRegisterBase, R_UART_MCR, 0x00, MmioEnable, RegisterStride);++    GuidHob = GET_NEXT_HOB (GuidHob);+    GuidHob = GetNextGuidHob (&gUniversalPayloadSerialPortInfoGuid, GuidHob);+  }++  return RETURN_SUCCESS;+}++/**+  Write data from buffer to serial device.++  Writes NumberOfBytes data bytes from Buffer to the serial device.+  The number of bytes actually written to the serial device is returned.+  If the return value is less than NumberOfBytes, then the write operation failed.++  If Buffer is NULL, then return 0.++  If NumberOfBytes is zero, then return 0.++  @param  Buffer           Pointer to the data buffer to be written.+  @param  NumberOfBytes    Number of bytes to written to the serial device.++  @retval 0                NumberOfBytes is 0.+  @retval >0               The number of bytes written to the serial device.+                           If this value is less than NumberOfBytes, then the write operation failed.++**/+UINTN+EFIAPI+SerialPortWrite (+  IN UINT8  *Buffer,+  IN UINTN  NumberOfBytes+  )+{+  UINTN    BaseAddress;+  BOOLEAN  UseMmio;+  UINTN    BytesLeft;+  UINTN    Index;+  UINTN    FifoSize;+  UINT8    *DataBuffer;+  UINT8    Count;+  UINT8    Stride;++  if ((Buffer == NULL) || (NumberOfBytes == 0) || (mUartCount == 0)) {+    return 0;+  }++  //+  // Compute the maximum size of the Tx FIFO+  //+  FifoSize = 1;+  if ((PcdGet8 (PcdSerialFifoControl) & B_UART_FCR_FIFOE) != 0) {+    if ((PcdGet8 (PcdSerialFifoControl) & B_UART_FCR_FIFO64) == 0) {+      FifoSize = 16;+    } else {+      FifoSize = PcdGet32 (PcdSerialExtendedTxFifoSize);+    }+  }++  Count = 0;+  while (Count < mUartCount) {+    BaseAddress = mUartInfo[Count].BaseAddress;+    UseMmio     = mUartInfo[Count].UseMmio;+    Stride      = mUartInfo[Count].RegisterStride;++    if (UseMmio && mBaseSerialPortLibHobAtRuntime) {+      Count++;+      continue;+    }++    if (BaseAddress == 0) {+      Count++;+      continue;+    }++    DataBuffer = Buffer;+    BytesLeft  = NumberOfBytes;++    while (BytesLeft != 0) {+      //+      // Wait for the serial port to be ready, to make sure both the transmit FIFO+      // and shift register empty.+      //+      while ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_TXRDY) == 0) {+      }++      //+      // Fill the entire Tx FIFO+      //+      for (Index = 0; Index < FifoSize && BytesLeft != 0; Index++, BytesLeft--, DataBuffer++) {+        //+        // Write byte to the transmit buffer.+        //+        SerialPortWriteRegister (BaseAddress, R_UART_TXBUF, *DataBuffer, UseMmio, Stride);+      }++      MicroSecondDelay (20);+    }++    Count++;+  }++  return NumberOfBytes;+}++/**+  Reads data from a serial device into a buffer.++  @param  Buffer           Pointer to the data buffer to store the data read from the serial device.+  @param  NumberOfBytes    Number of bytes to read from the serial device.++  @retval 0                NumberOfBytes is 0.+  @retval >0               The number of bytes read from the serial device.+                           If this value is less than NumberOfBytes, then the read operation failed.++**/+UINTN+EFIAPI+SerialPortRead (+  OUT UINT8  *Buffer,+  IN  UINTN  NumberOfBytes+  )+{+  UINTN    BaseAddress;+  BOOLEAN  UseMmio;+  BOOLEAN  IsNextPort;+  UINT8    *DataBuffer;+  UINTN    BytesLeft;+  UINTN    Result;+  UINT8    Mcr;+  UINT8    Count;+  UINT8    Stride;++  if (Buffer == NULL) {+    return 0;+  }++  Count = 0;+  while (Count < mUartCount) {+    BaseAddress = mUartInfo[Count].BaseAddress;+    UseMmio     = mUartInfo[Count].UseMmio;+    Stride      = mUartInfo[Count].RegisterStride;++    if (BaseAddress == 0) {+      Count++;+      continue;+    }++    DataBuffer = Buffer;+    BytesLeft  = NumberOfBytes;+    IsNextPort = FALSE;++    Mcr = (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) & ~B_UART_MCR_RTS);++    for (Result = 0; BytesLeft-- != 0; Result++, DataBuffer++) {+      //+      // Wait for the serial port to have some data.+      //+      while ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_RXRDY) == 0) {+        if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {+          //+          // Set RTS to let the peer send some data+          //+          SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(Mcr | B_UART_MCR_RTS), UseMmio, Stride);+        }++        IsNextPort = TRUE;+        break;+      }++      if (IsNextPort) {+        break;+      }++      if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {+        //+        // Clear RTS to prevent peer from sending data+        //+        SerialPortWriteRegister (BaseAddress, R_UART_MCR, Mcr, UseMmio, Stride);+      }++      //+      // Read byte from the receive buffer.+      //+      *DataBuffer = SerialPortReadRegister (BaseAddress, R_UART_RXBUF, UseMmio, Stride);+    }++    if ((!IsNextPort) && (*(--DataBuffer) != '\0')) {+      return Result;+    }++    Count++;+  }++  return Result;+}++/**+  Polls a serial device to see if there is any data waiting to be read.++  Polls a serial device to see if there is any data waiting to be read.+  If there is data waiting to be read from the serial device, then TRUE is returned.+  If there is no data waiting to be read from the serial device, then FALSE is returned.++  @retval TRUE             Data is waiting to be read from the serial device.+  @retval FALSE            There is no data waiting to be read from the serial device.++**/+BOOLEAN+EFIAPI+SerialPortPoll (+  VOID+  )+{+  UINTN    BaseAddress;+  BOOLEAN  UseMmio;+  UINT8    Stride;+  UINT8    Count;+  BOOLEAN  IsDataReady;++  Count = 0;+  while (Count < mUartCount) {+    BaseAddress = mUartInfo[Count].BaseAddress;+    UseMmio     = mUartInfo[Count].UseMmio;+    Stride      = mUartInfo[Count].RegisterStride;++    if (BaseAddress == 0) {+      Count++;+      continue;+    }++    IsDataReady = FALSE;++    //+    // Read the serial port status+    //+    if ((SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride) & B_UART_LSR_RXRDY) != 0) {+      if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {+        //+        // Clear RTS to prevent peer from sending data+        //+        SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) & ~B_UART_MCR_RTS), UseMmio, Stride);+      }++      IsDataReady = TRUE;+    }++    if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {+      //+      // Set RTS to let the peer send some data+      //+      SerialPortWriteRegister (BaseAddress, R_UART_MCR, (UINT8)(SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride) | B_UART_MCR_RTS), UseMmio, Stride);+    }++    if (IsDataReady) {+      return IsDataReady;+    }++    Count++;+  }++  return IsDataReady;+}++/**+  Sets the control bits on a serial device.++  @param Control                Sets the bits of Control that are settable.++  @retval RETURN_SUCCESS        The new control bits were set on the serial device.++**/+RETURN_STATUS+EFIAPI+SerialPortSetControl (+  IN UINT32  Control+  )+{+  UINTN    BaseAddress;+  BOOLEAN  UseMmio;+  UINT8    Mcr;+  UINT8    Count;+  UINT8    Stride;++  Count = 0;+  while (Count < mUartCount) {+    BaseAddress = mUartInfo[Count].BaseAddress;+    UseMmio     = mUartInfo[Count].UseMmio;+    Stride      = mUartInfo[Count].RegisterStride;++    if (BaseAddress == 0) {+      Count++;+      continue;+    }++    //+    // First determine the parameter is invalid.+    //+    if ((Control & (~(EFI_SERIAL_REQUEST_TO_SEND | EFI_SERIAL_DATA_TERMINAL_READY |+                      EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE))) != 0)+    {+      Count++;+      continue;+    }++    //+    // Read the Modem Control Register.+    //+    Mcr  = SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride);+    Mcr &= (~(B_UART_MCR_DTRC | B_UART_MCR_RTS));++    if ((Control & EFI_SERIAL_DATA_TERMINAL_READY) == EFI_SERIAL_DATA_TERMINAL_READY) {+      Mcr |= B_UART_MCR_DTRC;+    }++    if ((Control & EFI_SERIAL_REQUEST_TO_SEND) == EFI_SERIAL_REQUEST_TO_SEND) {+      Mcr |= B_UART_MCR_RTS;+    }++    //+    // Write the Modem Control Register.+    //+    SerialPortWriteRegister (BaseAddress, R_UART_MCR, Mcr, UseMmio, Stride);+    Count++;+  }++  return RETURN_SUCCESS;+}++/**+  Retrieve the status of the control bits on a serial device.++  @param Control                A pointer to return the current control signals from the serial device.++  @retval RETURN_SUCCESS        The control bits were read from the serial device.++**/+RETURN_STATUS+EFIAPI+SerialPortGetControl (+  OUT UINT32  *Control+  )+{+  UINTN    BaseAddress;+  BOOLEAN  UseMmio;+  UINT8    Msr;+  UINT8    Mcr;+  UINT8    Lsr;+  UINT8    Count;+  UINT8    Stride;++  Count = 0;+  while (Count < mUartCount) {+    BaseAddress = mUartInfo[Count].BaseAddress;+    UseMmio     = mUartInfo[Count].UseMmio;+    Stride      = mUartInfo[Count].RegisterStride;++    if (BaseAddress == 0) {+      Count++;+      continue;+    }++    *Control = 0;++    //+    // Read the Modem Status Register.+    //+    Msr = SerialPortReadRegister (BaseAddress, R_UART_MSR, UseMmio, Stride);++    if ((Msr & B_UART_MSR_CTS) == B_UART_MSR_CTS) {+      *Control |= EFI_SERIAL_CLEAR_TO_SEND;+    }++    if ((Msr & B_UART_MSR_DSR) == B_UART_MSR_DSR) {+      *Control |= EFI_SERIAL_DATA_SET_READY;+    }++    if ((Msr & B_UART_MSR_RI) == B_UART_MSR_RI) {+      *Control |= EFI_SERIAL_RING_INDICATE;+    }++    if ((Msr & B_UART_MSR_DCD) == B_UART_MSR_DCD) {+      *Control |= EFI_SERIAL_CARRIER_DETECT;+    }++    //+    // Read the Modem Control Register.+    //+    Mcr = SerialPortReadRegister (BaseAddress, R_UART_MCR, UseMmio, Stride);++    if ((Mcr & B_UART_MCR_DTRC) == B_UART_MCR_DTRC) {+      *Control |= EFI_SERIAL_DATA_TERMINAL_READY;+    }++    if ((Mcr & B_UART_MCR_RTS) == B_UART_MCR_RTS) {+      *Control |= EFI_SERIAL_REQUEST_TO_SEND;+    }++    if (PcdGetBool (PcdSerialUseHardwareFlowControl)) {+      *Control |= EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE;+    }++    //+    // Read the Line Status Register.+    //+    Lsr = SerialPortReadRegister (BaseAddress, R_UART_LSR, UseMmio, Stride);++    if ((Lsr & (B_UART_LSR_TEMT | B_UART_LSR_TXRDY)) == (B_UART_LSR_TEMT | B_UART_LSR_TXRDY)) {+      *Control |= EFI_SERIAL_OUTPUT_BUFFER_EMPTY;+    }++    if ((Lsr & B_UART_LSR_RXRDY) == 0) {+      *Control |= EFI_SERIAL_INPUT_BUFFER_EMPTY;+    }++    if ((((*Control & EFI_SERIAL_OUTPUT_BUFFER_EMPTY) == EFI_SERIAL_OUTPUT_BUFFER_EMPTY) &&+         ((*Control & EFI_SERIAL_INPUT_BUFFER_EMPTY) != EFI_SERIAL_INPUT_BUFFER_EMPTY)) ||+        ((*Control & (EFI_SERIAL_DATA_SET_READY | EFI_SERIAL_CLEAR_TO_SEND |+                      EFI_SERIAL_CARRIER_DETECT)) == (EFI_SERIAL_DATA_SET_READY | EFI_SERIAL_CLEAR_TO_SEND |+                                                      EFI_SERIAL_CARRIER_DETECT)))+    {+      return RETURN_SUCCESS;+    }++    Count++;+  }++  return RETURN_SUCCESS;+}++/**+  Sets the baud rate, receive FIFO depth, transmit/receice time out, parity,+  data bits, and stop bits on a serial device.++  @param BaudRate           The requested baud rate. A BaudRate value of 0 will use the+                            device's default interface speed.+                            On output, the value actually set.+  @param ReveiveFifoDepth   The requested depth of the FIFO on the receive side of the+                            serial interface. A ReceiveFifoDepth value of 0 will use+                            the device's default FIFO depth.+                            On output, the value actually set.+  @param Timeout            The requested time out for a single character in microseconds.+                            This timeout applies to both the transmit and receive side of the+                            interface. A Timeout value of 0 will use the device's default time+                            out value.+                            On output, the value actually set.+  @param Parity             The type of parity to use on this serial device. A Parity value of+                            DefaultParity will use the device's default parity value.+                            On output, the value actually set.+  @param DataBits           The number of data bits to use on the serial device. A DataBits+                            vaule of 0 will use the device's default data bit setting.+                            On output, the value actually set.+  @param StopBits           The number of stop bits to use on this serial device. A StopBits+                            value of DefaultStopBits will use the device's default number of+                            stop bits.+                            On output, the value actually set.++  @retval RETURN_SUCCESS            The new attributes were set on the serial device.++**/+RETURN_STATUS+EFIAPI+SerialPortSetAttributes (+  IN OUT UINT64              *BaudRate,+  IN OUT UINT32              *ReceiveFifoDepth,+  IN OUT UINT32              *Timeout,+  IN OUT EFI_PARITY_TYPE     *Parity,+  IN OUT UINT8               *DataBits,+  IN OUT EFI_STOP_BITS_TYPE  *StopBits+  )+{+  UINTN    BaseAddress;+  BOOLEAN  UseMmio;+  UINT32   SerialBaudRate;+  UINTN    Divisor;+  UINT8    Lcr;+  UINT8    LcrData;+  UINT8    LcrParity;+  UINT8    LcrStop;+  UINT8    Count;+  UINT8    Stride;++  Count = 0;+  while (Count < mUartCount) {+    BaseAddress = mUartInfo[Count].BaseAddress;+    UseMmio     = mUartInfo[Count].UseMmio;+    Stride      = mUartInfo[Count].RegisterStride;++    if (BaseAddress == 0) {+      Count++;+      continue;+    }++    //+    // Check for default settings and fill in actual values.+    //+    if (*BaudRate == 0) {+      *BaudRate = mUartInfo[Count].BaudRate;+    }++    SerialBaudRate = (UINT32)*BaudRate;++    if (*DataBits == 0) {+      LcrData   = (UINT8)(PcdGet8 (PcdSerialLineControl) & 0x3);+      *DataBits = LcrData + 5;+    } else {+      if ((*DataBits < 5) || (*DataBits > 8)) {+        Count++;+        continue;+      }++      //+      // Map 5..8 to 0..3+      //+      LcrData = (UINT8)(*DataBits - (UINT8)5);+    }++    if (*Parity == DefaultParity) {+      LcrParity = (UINT8)((PcdGet8 (PcdSerialLineControl) >> 3) & 0x7);+      switch (LcrParity) {+        case 0:+          *Parity = NoParity;+          break;++        case 3:+          *Parity = EvenParity;+          break;++        case 1:+          *Parity = OddParity;+          break;++        case 7:+          *Parity = SpaceParity;+          break;++        case 5:+          *Parity = MarkParity;+          break;++        default:+          break;+      }+    } else {+      switch (*Parity) {+        case NoParity:+          LcrParity = 0;+          break;++        case EvenParity:+          LcrParity = 3;+          break;++        case OddParity:+          LcrParity = 1;+          break;++        case SpaceParity:+          LcrParity = 7;+          break;++        case MarkParity:+          LcrParity = 5;+          break;++        default:+          Count++;+          continue;+      }+    }++    if (*StopBits == DefaultStopBits) {+      LcrStop = (UINT8)((PcdGet8 (PcdSerialLineControl) >> 2) & 0x1);+      switch (LcrStop) {+        case 0:+          *StopBits = OneStopBit;+          break;++        case 1:+          if (*DataBits == 5) {+            *StopBits = OneFiveStopBits;+          } else {+            *StopBits = TwoStopBits;+          }++          break;++        default:+          break;+      }+    } else {+      switch (*StopBits) {+        case OneStopBit:+          LcrStop = 0;+          break;++        case OneFiveStopBits:+        case TwoStopBits:+          LcrStop = 1;+          break;++        default:+          Count++;+          continue;+      }+    }++    //+    // Calculate divisor for baud generator+    //    Ref_Clk_Rate / Baud_Rate / 16+    //+    Divisor = PcdGet32 (PcdSerialClockRate) / (SerialBaudRate * 16);+    if ((PcdGet32 (PcdSerialClockRate) % (SerialBaudRate * 16)) >= SerialBaudRate * 8) {+      Divisor++;+    }++    //+    // Configure baud rate+    //+    SerialPortWriteRegister (BaseAddress, R_UART_LCR, B_UART_LCR_DLAB, UseMmio, Stride);+    SerialPortWriteRegister (BaseAddress, R_UART_BAUD_HIGH, (UINT8)(Divisor >> 8), UseMmio, Stride);+    SerialPortWriteRegister (BaseAddress, R_UART_BAUD_LOW, (UINT8)(Divisor & 0xff), UseMmio, Stride);++    //+    // Clear DLAB and configure Data Bits, Parity, and Stop Bits.+    // Strip reserved bits from line control value+    //+    Lcr = (UINT8)((LcrParity << 3) | (LcrStop << 2) | LcrData);+    SerialPortWriteRegister (BaseAddress, R_UART_LCR, (UINT8)(Lcr & 0x3F), UseMmio, Stride);+    Count++;+  }++  return RETURN_SUCCESS;+}++/**+  Set mSerialIoUartLibAtRuntime flag as TRUE after ExitBootServices.++  @param[in]  Event   The Event that is being processed.+  @param[in]  Context The Event Context.++**/+STATIC+VOID+EFIAPI+BaseSerialPortLibHobExitBootServicesEvent (+  IN EFI_EVENT  Event,+  IN VOID       *Context+  )+{+  mBaseSerialPortLibHobAtRuntime = TRUE;+}++/**+  The constructor function registers a callback for the ExitBootServices event.++  @param[in]  ImageHandle   The firmware allocated handle for the EFI image.+  @param[in]  SystemTable   A pointer to the EFI System Table.++  @retval EFI_SUCCESS   The operation completed successfully.+  @retval other         Either the serial port failed to initialize or the+                        ExitBootServices event callback registration failed.+**/+EFI_STATUS+EFIAPI+DxeBaseSerialPortLibHobConstructor (+  IN EFI_HANDLE        ImageHandle,+  IN EFI_SYSTEM_TABLE  *SystemTable+  )+{+  return SystemTable->BootServices->CreateEvent (+                                      EVT_SIGNAL_EXIT_BOOT_SERVICES,+                                      TPL_NOTIFY,+                                      BaseSerialPortLibHobExitBootServicesEvent,+                                      NULL,+                                      &mBaseSerialPortLibHobExitBootServicesEvent+                                      );+}diff --git a/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf b/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf
new file mode 100644
index 0000000000..e16a9a4a83
--- /dev/null
+++ b/UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHo
+++ b.inf
@@ -0,0 +1,40 @@
+## @file+#  SerialPortLib instance for UART information retrieved from bootloader.+#+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>+#+#  SPDX-License-Identifier: BSD-2-Clause-Patent+#+##++[Defines]+  INF_VERSION                    = 0x00010005+  BASE_NAME                      = DxeBaseSerialPortLibHob+  FILE_GUID                      = c8def0c5-48e7-45b8-8299-485ea2e63b2c+  MODULE_TYPE                    = DXE_DRIVER+  VERSION_STRING                 = 1.0+  LIBRARY_CLASS                  = SerialPortLib|DXE_CORE DXE_DRIVER DXE_RUNTIME_DRIVER DXE_SMM_DRIVER UEFI_APPLICATION UEFI_DRIVER+  CONSTRUCTOR                    = DxeBaseSerialPortLibHobConstructor++[Packages]+  MdePkg/MdePkg.dec+  MdeModulePkg/MdeModulePkg.dec++[LibraryClasses]+  PcdLib+  IoLib+  HobLib+  TimerLib++[Sources]+  DxeBaseSerialPortLibHob.c++[Pcd]+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialLineControl+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialFifoControl+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialClockRate+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialExtendedTxFifoSize+  gEfiMdeModulePkgTokenSpaceGuid.PcdSerialUseHardwareFlowControl++[Guids]+  gUniversalPayloadSerialPortInfoGuiddiff --git a/UefiPayloadPkg/UefiPayloadPkg.dsc b/UefiPayloadPkg/UefiPayloadPkg.dsc
index 9847f189ff..998d222909 100644
--- a/UefiPayloadPkg/UefiPayloadPkg.dsc
+++ b/UefiPayloadPkg/UefiPayloadPkg.dsc
@@ -256,7 +256,11 @@
   SerialPortLib|UefiPayloadPkg/Library/CbSerialPortLib/CbSerialPortLib.inf   PlatformHookLib|MdeModulePkg/Library/BasePlatformHookLibNull/BasePlatformHookLibNull.inf !else-  SerialPortLib|MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf+  !if $(MULTIPLE_DEBUG_PORT_SUPPORT) == TRUE+    SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf+  !else+    SerialPortLib|MdeModulePkg/Library/BaseSerialPortLib16550/BaseSerialPortLib16550.inf+  !endif   PlatformHookLib|UefiPayloadPkg/Library/PlatformHookLib/PlatformHookLib.inf !endif   PlatformBootManagerLib|UefiPayloadPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf@@ -313,6 +317,9 @@
   PcdLib|MdePkg/Library/BasePcdLibNull/BasePcdLibNull.inf   DxeHobListLib|UefiPayloadPkg/Library/DxeHobListLibNull/DxeHobListLibNull.inf   DebugLib|MdePkg/Library/BaseDebugLibSerialPort/BaseDebugLibSerialPort.inf+!if $(MULTIPLE_DEBUG_PORT_SUPPORT) == TRUE+  SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf+!endif  [LibraryClasses.common.DXE_CORE]   DxeHobListLib|UefiPayloadPkg/Library/DxeHobListLibNull/DxeHobListLibNull.inf@@ -617,7 +624,7 @@
     <LibraryClasses>       !if $(MULTIPLE_DEBUG_PORT_SUPPORT) == TRUE         DebugLib|MdePkg/Library/BaseDebugLibSerialPort/BaseDebugLibSerialPort.inf-        SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/BaseSerialPortLibHob.inf+        SerialPortLib|UefiPayloadPkg/Library/BaseSerialPortLibHob/DxeBaseSerialPortLibHob.inf       !endif       NULL|MdeModulePkg/Library/LzmaCustomDecompressLib/LzmaCustomDecompressLib.inf   }-- 
2.39.2.windows.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [edk2-devel] [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true
  2023-04-27  6:13 [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true paytonx.hsieh
  2023-04-27  6:17 ` Guo, Gua
@ 2023-04-27 17:36 ` Benjamin Doron
  2023-04-27 22:38   ` Guo, Gua
  2023-04-28  2:33   ` Hsieh, PaytonX
  1 sibling, 2 replies; 6+ messages in thread
From: Benjamin Doron @ 2023-04-27 17:36 UTC (permalink / raw)
  To: paytonx.hsieh, devel

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Hi,
Can you deduplicate this code by moving the functions into a common, or "base" file, and DXE's constructor and event into a separate file? As I see it, it should be alright to reuse DXE's functions for other phases, the ` mBaseSerialPortLibHobAtRuntime` variable will never be changed in this case.

Regards,
Benjamin

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [edk2-devel] [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true
  2023-04-27 17:36 ` [edk2-devel] " Benjamin Doron
@ 2023-04-27 22:38   ` Guo, Gua
  2023-04-28  2:33   ` Hsieh, PaytonX
  1 sibling, 0 replies; 6+ messages in thread
From: Guo, Gua @ 2023-04-27 22:38 UTC (permalink / raw)
  To: devel@edk2.groups.io, benjamin.doron00@gmail.com, Hsieh, PaytonX

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Hi Payton

For BaseSerialPortLibHob.inf please use BaseSerialPortLibHob.c
For DxeSerialPortLibHob.inf please use BaseSerialPortLibHob.c and DxeSerialPortLibHob.c and remove redundant code.

Have any limitation, please share for us.

Thanks,
Gua

From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Benjamin Doron
Sent: Friday, April 28, 2023 1:36 AM
To: Hsieh, PaytonX <paytonx.hsieh@intel.com>; devel@edk2.groups.io
Subject: Re: [edk2-devel] [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true

Hi,
Can you deduplicate this code by moving the functions into a common, or "base" file, and DXE's constructor and event into a separate file? As I see it, it should be alright to reuse DXE's functions for other phases, the `mBaseSerialPortLibHobAtRuntime` variable will never be changed in this case.

Regards,
Benjamin


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^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [edk2-devel] [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true
  2023-04-27 17:36 ` [edk2-devel] " Benjamin Doron
  2023-04-27 22:38   ` Guo, Gua
@ 2023-04-28  2:33   ` Hsieh, PaytonX
  2023-04-28 13:54     ` Benjamin Doron
  1 sibling, 1 reply; 6+ messages in thread
From: Hsieh, PaytonX @ 2023-04-28  2:33 UTC (permalink / raw)
  To: Benjamin Doron, devel@edk2.groups.io

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Hi Benjamin,

Due to some platform will disable the MMIO access of UART in ExitBootServices event.

So we register an ExitBootServices event to avoid access the invalid MMIO space, it will cause the system hang when boot to windows OS.

And the serial port library is also used in SEC and PEI phase, we will need another DXE library to avoid build error or possible system hang while the Boot Service is not available in PEI or SEC phase.

From: Benjamin Doron <benjamin.doron00@gmail.com>
Sent: Friday, April 28, 2023 1:36 AM
To: Hsieh, PaytonX <paytonx.hsieh@intel.com>; devel@edk2.groups.io
Subject: Re: [edk2-devel] [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true

Hi,
Can you deduplicate this code by moving the functions into a common, or "base" file, and DXE's constructor and event into a separate file? As I see it, it should be alright to reuse DXE's functions for other phases, the `mBaseSerialPortLibHobAtRuntime` variable will never be changed in this case.

Regards,
Benjamin

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [edk2-devel] [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true
  2023-04-28  2:33   ` Hsieh, PaytonX
@ 2023-04-28 13:54     ` Benjamin Doron
  0 siblings, 0 replies; 6+ messages in thread
From: Benjamin Doron @ 2023-04-28 13:54 UTC (permalink / raw)
  To: Hsieh, PaytonX, devel@edk2.groups.io

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Hi Payton,
Thanks for responding. I understand the idea of the patch, Gua described my idea better. I was thinking that there would be two library instances, BaseSerialPortLibHob.inf and DxeSerialPortLibHob.inf. BASE compiles only BaseSerialPortLibHob.c, and DXE compiles the BaseSerialPortLibHob.c and a small DxeSerialPortLibHob.c with the constructor and event for DXE. The idea is to have this improved behaviour with less code added.

I can implement and test the deduplication if you prefer.

Best regards,
Benjamin

On April 27, 2023 10:33:09 p.m. EDT, "Hsieh, PaytonX" <paytonx.hsieh@intel.com> wrote:
>Hi Benjamin,
>
>Due to some platform will disable the MMIO access of UART in ExitBootServices event.
>
>So we register an ExitBootServices event to avoid access the invalid MMIO space, it will cause the system hang when boot to windows OS.
>
>And the serial port library is also used in SEC and PEI phase, we will need another DXE library to avoid build error or possible system hang while the Boot Service is not available in PEI or SEC phase.
>
>From: Benjamin Doron <benjamin.doron00@gmail.com>
>Sent: Friday, April 28, 2023 1:36 AM
>To: Hsieh, PaytonX <paytonx.hsieh@intel.com>; devel@edk2.groups.io
>Subject: Re: [edk2-devel] [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true
>
>Hi,
>Can you deduplicate this code by moving the functions into a common, or "base" file, and DXE's constructor and event into a separate file? As I see it, it should be alright to reuse DXE's functions for other phases, the `mBaseSerialPortLibHobAtRuntime` variable will never be changed in this case.
>
>Regards,
>Benjamin

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^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2023-04-28 13:54 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-04-27  6:13 [PATCH] UefiPayloadPkg: Fix issues when MULTIPLE_DEBUG_PORT_SUPPORT is true paytonx.hsieh
2023-04-27  6:17 ` Guo, Gua
2023-04-27 17:36 ` [edk2-devel] " Benjamin Doron
2023-04-27 22:38   ` Guo, Gua
2023-04-28  2:33   ` Hsieh, PaytonX
2023-04-28 13:54     ` Benjamin Doron

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