diff options
Diffstat (limited to 'EmbeddedPkg/Library/GdbSerialLib/GdbSerialLib.c')
| -rw-r--r-- | EmbeddedPkg/Library/GdbSerialLib/GdbSerialLib.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/EmbeddedPkg/Library/GdbSerialLib/GdbSerialLib.c b/EmbeddedPkg/Library/GdbSerialLib/GdbSerialLib.c new file mode 100644 index 0000000000..62d8636456 --- /dev/null +++ b/EmbeddedPkg/Library/GdbSerialLib/GdbSerialLib.c @@ -0,0 +1,262 @@ +/** @file
+ Basic serial IO abstaction for GDB
+
+ Copyright (c) 2008-2009, Apple Inc. All rights reserved.
+
+ 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 <Uefi.h>
+#include <Library/GdbSerialLib.h>
+#include <Library/PcdLib.h>
+#include <Library/IoLib.h>
+#include <Library/DebugLib.h>
+
+
+//---------------------------------------------
+// UART Register Offsets
+//---------------------------------------------
+#define BAUD_LOW_OFFSET 0x00
+#define BAUD_HIGH_OFFSET 0x01
+#define IER_OFFSET 0x01
+#define LCR_SHADOW_OFFSET 0x01
+#define FCR_SHADOW_OFFSET 0x02
+#define IR_CONTROL_OFFSET 0x02
+#define FCR_OFFSET 0x02
+#define EIR_OFFSET 0x02
+#define BSR_OFFSET 0x03
+#define LCR_OFFSET 0x03
+#define MCR_OFFSET 0x04
+#define LSR_OFFSET 0x05
+#define MSR_OFFSET 0x06
+
+//---------------------------------------------
+// UART Register Bit Defines
+//---------------------------------------------
+#define LSR_TXRDY 0x20
+#define LSR_RXDA 0x01
+#define DLAB 0x01
+#define ENABLE_FIFO 0x01
+#define CLEAR_FIFOS 0x06
+
+
+
+// IO Port Base for the UART
+UINTN gPort;
+
+
+/**
+ The constructor function initializes the UART.
+
+ @param ImageHandle The firmware allocated handle for the EFI image.
+ @param SystemTable A pointer to the EFI System Table.
+
+ @retval EFI_SUCCESS The constructor always returns EFI_SUCCESS.
+
+**/
+RETURN_STATUS
+EFIAPI
+GdbSerialLibConstructor (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ UINT64 BaudRate;
+ UINT8 DataBits;
+ UINT8 Parity;
+ UINT8 StopBits;
+
+ gPort = (UINTN)PcdGet32 (PcdGdbUartPort);
+
+ BaudRate = PcdGet64 (PcdGdbBaudRate);
+ Parity = PcdGet8 (PcdGdbParity);
+ DataBits = PcdGet8 (PcdGdbDataBits);
+ StopBits = PcdGet8 (PcdGdbStopBits);
+
+ return GdbSerialInit (BaudRate, Parity, DataBits, StopBits);
+}
+
+
+
+/**
+ Sets the baud rate, receive FIFO depth, transmit/receice time out, parity,
+ data buts, and stop bits on a serial device. This call is optional as the serial
+ port will be set up with defaults base on PCD values.
+
+ @param BaudRate The requested baud rate. A BaudRate value of 0 will use the the
+ device's default interface speed.
+ @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.
+ @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.
+ @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.
+
+ @retval EFI_SUCCESS The device was configured.
+ @retval EFI_DEVICE_ERROR The serial device could not be coonfigured.
+
+**/
+RETURN_STATUS
+EFIAPI
+GdbSerialInit (
+ IN UINT64 BaudRate,
+ IN UINT8 Parity,
+ IN UINT8 DataBits,
+ IN UINT8 StopBits
+ )
+{
+ UINTN Divisor;
+ UINT8 OutputData;
+ UINT8 Data;
+ UINT8 BreakSet = 0;
+
+ //
+ // We assume the UART has been turned on to decode gPort address range
+ //
+
+ //
+ // Map 5..8 to 0..3
+ //
+ Data = (UINT8) (DataBits - (UINT8)5);
+
+ //
+ // Calculate divisor for baud generator
+ //
+ Divisor = 115200/(UINTN)BaudRate;
+
+ //
+ // Set communications format
+ //
+ OutputData = (UINT8)((DLAB << 7) | ((BreakSet << 6) | ((Parity << 3) | ((StopBits << 2) | Data))));
+ IoWrite8 (gPort + LCR_OFFSET, OutputData);
+
+ //
+ // Configure baud rate
+ //
+ IoWrite8 (gPort + BAUD_HIGH_OFFSET, (UINT8)(Divisor >> 8));
+ IoWrite8 (gPort + BAUD_LOW_OFFSET, (UINT8)(Divisor & 0xff));
+
+
+ //
+ // Switch back to bank 0
+ //
+ OutputData = (UINT8)((~DLAB<<7)|((BreakSet<<6)|((Parity<<3)|((StopBits<<2)| Data))));
+ IoWrite8 (gPort + LCR_OFFSET, OutputData);
+
+ // Not sure this is the right place to enable the FIFOs....
+ // We probably need the FIFO enabled to not drop input
+ IoWrite8 (gPort + FCR_SHADOW_OFFSET, ENABLE_FIFO);
+
+
+ // Configure the UART hardware here
+ return RETURN_SUCCESS;
+}
+
+
+/**
+ Check to see if a character is available from GDB. Do not read the character as that is
+ done via GdbGetChar().
+
+ @return TRUE - Character availible
+ @return FALSE - Character not availible
+
+**/
+BOOLEAN
+EFIAPI
+GdbIsCharAvailable (
+ VOID
+ )
+{
+ UINT8 Data;
+
+ Data = IoRead8 (gPort + LSR_OFFSET);
+
+ return ((Data & LSR_RXDA) == LSR_RXDA);
+}
+
+
+/**
+ Get a character from GDB. This function must be able to run in interrupt context.
+
+ @return A character from GDB
+
+**/
+CHAR8
+EFIAPI
+GdbGetChar (
+ VOID
+ )
+{
+ UINT8 Data;
+ CHAR8 Char;
+
+ // Wait for the serial port to be ready
+ do {
+ Data = IoRead8 (gPort + LSR_OFFSET);
+ } while ((Data & LSR_RXDA) == 0);
+
+ Char = IoRead8 (gPort);
+
+ // Make this an EFI_D_INFO after we get everything debugged.
+ DEBUG ((EFI_D_ERROR, "<%c<", Char));
+ return Char;
+}
+
+
+/**
+ Send a character to GDB. This function must be able to run in interrupt context.
+
+
+ @param Char Send a character to GDB
+
+**/
+
+VOID
+EFIAPI
+GdbPutChar (
+ IN CHAR8 Char
+ )
+{
+ UINT8 Data;
+
+ // Make this an EFI_D_INFO after we get everything debugged.
+ DEBUG ((EFI_D_ERROR, ">%c>", Char));
+
+ // Wait for the serial port to be ready
+ do {
+ Data = IoRead8 (gPort + LSR_OFFSET);
+ } while ((Data & LSR_TXRDY) == 0);
+
+ IoWrite8 (gPort, Char);
+}
+
+/**
+ Send an ASCII string to GDB. This function must be able to run in interrupt context.
+
+
+ @param String Send a string to GDB
+
+**/
+
+VOID
+GdbPutString (
+ IN CHAR8 *String
+ )
+{
+ while (*String != '\0') {
+ GdbPutChar (*String);
+ String++;
+ }
+}
+
+
+
+
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