UefiCpuPkg: Move AsmRelocateApLoopStart from Mpfuncs.nasm to AmdSev.nasm

[mirror_edk2.git] / EmbeddedPkg / Library / GdbSerialLib / GdbSerialLib.c

/** @file\r
  Basic serial IO abstraction for GDB\r
\r
  Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include <Uefi.h>\r
#include <Library/GdbSerialLib.h>\r
#include <Library/PcdLib.h>\r
#include <Library/IoLib.h>\r
#include <Library/DebugLib.h>\r
\r
// ---------------------------------------------\r
// UART Register Offsets\r
// ---------------------------------------------\r
#define BAUD_LOW_OFFSET    0x00\r
#define BAUD_HIGH_OFFSET   0x01\r
#define IER_OFFSET         0x01\r
#define LCR_SHADOW_OFFSET  0x01\r
#define FCR_SHADOW_OFFSET  0x02\r
#define IR_CONTROL_OFFSET  0x02\r
#define FCR_OFFSET         0x02\r
#define EIR_OFFSET         0x02\r
#define BSR_OFFSET         0x03\r
#define LCR_OFFSET         0x03\r
#define MCR_OFFSET         0x04\r
#define LSR_OFFSET         0x05\r
#define MSR_OFFSET         0x06\r
\r
// ---------------------------------------------\r
// UART Register Bit Defines\r
// ---------------------------------------------\r
#define LSR_TXRDY    0x20U\r
#define LSR_RXDA     0x01U\r
#define DLAB         0x01U\r
#define ENABLE_FIFO  0x01U\r
#define CLEAR_FIFOS  0x06U\r
\r
// IO Port Base for the UART\r
UINTN  gPort;\r
\r
/**\r
  The constructor function initializes the UART.\r
\r
  @param  ImageHandle   The firmware allocated handle for the EFI image.\r
  @param  SystemTable   A pointer to the EFI System Table.\r
\r
  @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.\r
\r
**/\r
RETURN_STATUS\r
EFIAPI\r
GdbSerialLibConstructor (\r
  IN EFI_HANDLE        ImageHandle,\r
  IN EFI_SYSTEM_TABLE  *SystemTable\r
  )\r
{\r
  UINT64  BaudRate;\r
  UINT8   DataBits;\r
  UINT8   Parity;\r
  UINT8   StopBits;\r
\r
  gPort = (UINTN)PcdGet32 (PcdGdbUartPort);\r
\r
  BaudRate = PcdGet64 (PcdGdbBaudRate);\r
  Parity   = PcdGet8 (PcdGdbParity);\r
  DataBits = PcdGet8 (PcdGdbDataBits);\r
  StopBits = PcdGet8 (PcdGdbStopBits);\r
\r
  return GdbSerialInit (BaudRate, Parity, DataBits, StopBits);\r
}\r
\r
/**\r
  Sets the baud rate, receive FIFO depth, transmit/receive time out, parity,\r
  data buts, and stop bits on a serial device. This call is optional as the serial\r
  port will be set up with defaults base on PCD values.\r
\r
  @param  BaudRate         The requested baud rate. A BaudRate value of 0 will use the\r
                           device's default interface speed.\r
  @param  Parity           The type of parity to use on this serial device. A Parity value of\r
                           DefaultParity will use the device's default parity value.\r
  @param  DataBits         The number of data bits to use on the serial device. A DataBits\r
                           value of 0 will use the device's default data bit setting.\r
  @param  StopBits         The number of stop bits to use on this serial device. A StopBits\r
                           value of DefaultStopBits will use the device's default number of\r
                           stop bits.\r
\r
  @retval EFI_SUCCESS      The device was configured.\r
  @retval EFI_DEVICE_ERROR The serial device could not be configured.\r
\r
**/\r
RETURN_STATUS\r
EFIAPI\r
GdbSerialInit (\r
  IN UINT64  BaudRate,\r
  IN UINT8   Parity,\r
  IN UINT8   DataBits,\r
  IN UINT8   StopBits\r
  )\r
{\r
  UINTN  Divisor;\r
  UINT8  OutputData;\r
  UINT8  Data;\r
  UINT8  BreakSet = 0;\r
\r
  //\r
  // We assume the UART has been turned on to decode gPort address range\r
  //\r
\r
  //\r
  // Map 5..8 to 0..3\r
  //\r
  Data = (UINT8)(DataBits - (UINT8)5);\r
\r
  //\r
  // Calculate divisor for baud generator\r
  //\r
  Divisor = 115200/(UINTN)BaudRate;\r
\r
  //\r
  // Set communications format\r
  //\r
  OutputData = (UINT8)((DLAB << 7) | ((BreakSet << 6) | ((Parity << 3) | ((StopBits << 2) | Data))));\r
  IoWrite8 (gPort + LCR_OFFSET, OutputData);\r
\r
  //\r
  // Configure baud rate\r
  //\r
  IoWrite8 (gPort + BAUD_HIGH_OFFSET, (UINT8)(Divisor >> 8));\r
  IoWrite8 (gPort + BAUD_LOW_OFFSET, (UINT8)(Divisor & 0xff));\r
\r
  //\r
  // Switch back to bank 0\r
  //\r
  OutputData = (UINT8)((~DLAB<<7)|((BreakSet<<6)|((Parity<<3)|((StopBits<<2)| Data))));\r
  IoWrite8 (gPort + LCR_OFFSET, OutputData);\r
\r
  // Not sure this is the right place to enable the FIFOs....\r
  // We probably need the FIFO enabled to not drop input\r
  IoWrite8 (gPort + FCR_SHADOW_OFFSET, ENABLE_FIFO);\r
\r
  // Configure the UART hardware here\r
  return RETURN_SUCCESS;\r
}\r
\r
/**\r
  Check to see if a character is available from GDB. Do not read the character as that is\r
  done via GdbGetChar().\r
\r
  @return TRUE  - Character available\r
  @return FALSE - Character not available\r
\r
**/\r
BOOLEAN\r
EFIAPI\r
GdbIsCharAvailable (\r
  VOID\r
  )\r
{\r
  UINT8  Data;\r
\r
  Data = IoRead8 (gPort + LSR_OFFSET);\r
\r
  return ((Data & LSR_RXDA) == LSR_RXDA);\r
}\r
\r
/**\r
  Get a character from GDB. This function must be able to run in interrupt context.\r
\r
  @return A character from GDB\r
\r
**/\r
CHAR8\r
EFIAPI\r
GdbGetChar (\r
  VOID\r
  )\r
{\r
  UINT8  Data;\r
  CHAR8  Char;\r
\r
  // Wait for the serial port to be ready\r
  do {\r
    Data = IoRead8 (gPort + LSR_OFFSET);\r
  } while ((Data & LSR_RXDA) == 0);\r
\r
  Char = IoRead8 (gPort);\r
\r
  // Make this an DEBUG_INFO after we get everything debugged.\r
  DEBUG ((DEBUG_ERROR, "<%c<", Char));\r
  return Char;\r
}\r
\r
/**\r
  Send a character to GDB. This function must be able to run in interrupt context.\r
\r
\r
  @param  Char    Send a character to GDB\r
\r
**/\r
VOID\r
EFIAPI\r
GdbPutChar (\r
  IN  CHAR8  Char\r
  )\r
{\r
  UINT8  Data;\r
\r
  // Make this an DEBUG_INFO after we get everything debugged.\r
  DEBUG ((DEBUG_ERROR, ">%c>", Char));\r
\r
  // Wait for the serial port to be ready\r
  do {\r
    Data = IoRead8 (gPort + LSR_OFFSET);\r
  } while ((Data & LSR_TXRDY) == 0);\r
\r
  IoWrite8 (gPort, Char);\r
}\r
\r
/**\r
  Send an ASCII string to GDB. This function must be able to run in interrupt context.\r
\r
\r
  @param  String    Send a string to GDB\r
\r
**/\r
VOID\r
GdbPutString (\r
  IN CHAR8  *String\r
  )\r
{\r
  while (*String != '\0') {\r
    GdbPutChar (*String);\r
    String++;\r
  }\r
}\r