summaryrefslogtreecommitdiff
path: root/EmbeddedPkg/GdbStub/Ia32/Processor.c
diff options
context:
space:
mode:
Diffstat (limited to 'EmbeddedPkg/GdbStub/Ia32/Processor.c')
-rw-r--r--EmbeddedPkg/GdbStub/Ia32/Processor.c993
1 files changed, 993 insertions, 0 deletions
diff --git a/EmbeddedPkg/GdbStub/Ia32/Processor.c b/EmbeddedPkg/GdbStub/Ia32/Processor.c
new file mode 100644
index 0000000000..90a2224edf
--- /dev/null
+++ b/EmbeddedPkg/GdbStub/Ia32/Processor.c
@@ -0,0 +1,993 @@
+/** @file
+ Processor specific parts of the GDB stub
+
+ 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 <GdbStubInternal.h>
+
+//
+// Array of exception types that need to be hooked by the debugger
+// {EFI mapping, GDB mapping}
+//
+EFI_EXCEPTION_TYPE_ENTRY gExceptionType[] = {
+ { EXCEPT_IA32_DIVIDE_ERROR, GDB_SIGFPE },
+ { EXCEPT_IA32_DEBUG, GDB_SIGTRAP },
+ { EXCEPT_IA32_NMI, GDB_SIGEMT },
+ { EXCEPT_IA32_BREAKPOINT, GDB_SIGTRAP },
+ { EXCEPT_IA32_OVERFLOW, GDB_SIGSEGV },
+ { EXCEPT_IA32_BOUND, GDB_SIGSEGV },
+ { EXCEPT_IA32_INVALID_OPCODE, GDB_SIGILL },
+ { EXCEPT_IA32_DOUBLE_FAULT, GDB_SIGEMT },
+ { EXCEPT_IA32_STACK_FAULT, GDB_SIGSEGV },
+ { EXCEPT_IA32_GP_FAULT, GDB_SIGSEGV },
+ { EXCEPT_IA32_PAGE_FAULT, GDB_SIGSEGV },
+ { EXCEPT_IA32_FP_ERROR, GDB_SIGEMT },
+ { EXCEPT_IA32_ALIGNMENT_CHECK, GDB_SIGEMT },
+ { EXCEPT_IA32_MACHINE_CHECK, GDB_SIGEMT }
+};
+
+
+// The offsets of registers SystemContext.
+// The fields in the array are in the gdb ordering.
+//
+//16 regs
+UINTN gRegisterOffsets[] = {
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Eax),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Ecx),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Edx),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Ebx),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Esp),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Ebp),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Esi),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Edi),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Eip),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Eflags),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Cs),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Ss),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Ds),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Es),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Fs),
+ OFFSET_OF(EFI_SYSTEM_CONTEXT_IA32, Gs)
+};
+
+
+//Debug only..
+VOID
+PrintReg (
+ IN EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ Print ((CHAR16 *)L"EAX: %x ", SystemContext.SystemContextIa32->Eax);
+ Print ((CHAR16 *)L"ECX: %x ", SystemContext.SystemContextIa32->Ecx);
+ Print ((CHAR16 *)L"EDX: %x ", SystemContext.SystemContextIa32->Edx);
+ Print ((CHAR16 *)L"EBX: %x ", SystemContext.SystemContextIa32->Ebx);
+ Print ((CHAR16 *)L"ESP: %x ", SystemContext.SystemContextIa32->Esp);
+ Print ((CHAR16 *)L"EBP: %x ", SystemContext.SystemContextIa32->Ebp);
+ Print ((CHAR16 *)L"ESI: %x ", SystemContext.SystemContextIa32->Esi);
+ Print ((CHAR16 *)L"EDI: %x ", SystemContext.SystemContextIa32->Edi);
+ Print ((CHAR16 *)L"EIP: %x\n", SystemContext.SystemContextIa32->Eip);
+ Print ((CHAR16 *)L"EFlags: %x\n", SystemContext.SystemContextIa32->Eflags);
+}
+
+//Debug only..
+VOID
+PrintDRreg (
+ IN EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ Print ((CHAR16 *)L"DR0: %x ", SystemContext.SystemContextIa32->Dr0);
+ Print ((CHAR16 *)L"DR1: %x ", SystemContext.SystemContextIa32->Dr1);
+ Print ((CHAR16 *)L"DR2: %x ", SystemContext.SystemContextIa32->Dr2);
+ Print ((CHAR16 *)L"DR3: %x ", SystemContext.SystemContextIa32->Dr3);
+ Print ((CHAR16 *)L"DR6: %x ", SystemContext.SystemContextIa32->Dr6);
+ Print ((CHAR16 *)L"DR7: %x\n", SystemContext.SystemContextIa32->Dr7);
+}
+
+
+/**
+ Return the number of entries in the gExceptionType[]
+
+ @retval UINTN, the number of entries in the gExceptionType[] array.
+ **/
+UINTN
+MaxEfiException (
+ VOID
+ )
+{
+ return sizeof (gExceptionType)/sizeof (EFI_EXCEPTION_TYPE_ENTRY);
+}
+
+
+/**
+ Return the number of entries in the gRegisters[]
+
+ @retval UINTN, the number of entries (registers) in the gRegisters[] array.
+ **/
+UINTN
+MaxRegisterCount (
+ VOID
+ )
+{
+ return sizeof (gRegisterOffsets)/sizeof (UINTN);
+}
+
+
+/**
+ Check to see if the ISA is supported.
+ ISA = Instruction Set Architecture
+
+ @retval TRUE if Isa is supported,
+ FALSE otherwise.
+**/
+BOOLEAN
+CheckIsa (
+ IN EFI_INSTRUCTION_SET_ARCHITECTURE Isa
+ )
+{
+ return (BOOLEAN)(Isa == IsaIa32);
+}
+
+
+/**
+ This takes in the register number and the System Context, and returns a pointer to the RegNumber-th register in gdb ordering
+ It is, by default, set to find the register pointer of the IA32 member
+
+ @param SystemContext Register content at time of the exception
+ @param RegNumber The register to which we want to find a pointer
+ @retval the pointer to the RegNumber-th pointer
+ **/
+UINTN *
+FindPointerToRegister(
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN UINTN RegNumber
+ )
+{
+ UINT8 *TempPtr;
+ TempPtr = ((UINT8 *)SystemContext.SystemContextIa32) + gRegisterOffsets[RegNumber];
+ return (UINTN *)TempPtr;
+}
+
+
+/**
+ Adds the RegNumber-th register's value to the output buffer, starting at the given OutBufPtr
+
+ @param SystemContext Register content at time of the exception
+ @param RegNumber the number of the register that we want to read
+ @param OutBufPtr pointer to the output buffer's end. the new data will be added from this point on.
+ @retval the pointer to the next character of the output buffer that is available to be written on.
+ **/
+CHAR8 *
+BasicReadRegister (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN UINTN RegNumber,
+ IN CHAR8 *OutBufPtr
+ )
+{
+ UINTN RegSize;
+
+ RegSize = 0;
+ while (RegSize < REG_SIZE) {
+ *OutBufPtr++ = mHexToStr[((*FindPointerToRegister(SystemContext, RegNumber) >> (RegSize+4)) & 0xf)];
+ *OutBufPtr++ = mHexToStr[((*FindPointerToRegister(SystemContext, RegNumber) >> RegSize) & 0xf)];
+ RegSize = RegSize + 8;
+ }
+ return OutBufPtr;
+}
+
+
+/** ‘p n’
+ Reads the n-th register's value into an output buffer and sends it as a packet
+
+ @param SystemContext Register content at time of the exception
+ @param InBuffer Pointer to the input buffer received from gdb server
+ **/
+VOID
+EFIAPI
+ReadNthRegister (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN CHAR8 *InBuffer
+ )
+{
+ UINTN RegNumber;
+ CHAR8 OutBuffer[9]; // 1 reg=8 hex chars, and the end '\0' (escape seq)
+ CHAR8 *OutBufPtr; // pointer to the output buffer
+
+ RegNumber = AsciiStrHexToUintn (&InBuffer[1]);
+
+ if ((RegNumber < 0) || (RegNumber >= MaxRegisterCount())) {
+ SendError (GDB_EINVALIDREGNUM);
+ return;
+ }
+
+ OutBufPtr = OutBuffer;
+ OutBufPtr = BasicReadRegister(SystemContext, RegNumber, OutBufPtr);
+
+ *OutBufPtr = '\0'; // the end of the buffer
+ SendPacket(OutBuffer);
+}
+
+
+/** ‘g’
+ Reads the general registers into an output buffer and sends it as a packet
+
+ @param SystemContext Register content at time of the exception
+ **/
+VOID
+EFIAPI
+ReadGeneralRegisters (
+ IN EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ UINTN i;
+ CHAR8 OutBuffer[129]; // 16 regs, 8 hex chars each, and the end '\0' (escape seq)
+ CHAR8 *OutBufPtr; // pointer to the output buffer
+
+ OutBufPtr = OutBuffer;
+ for(i = 0 ; i < MaxRegisterCount() ; i++) { // there are only 16 registers to read
+ OutBufPtr = BasicReadRegister(SystemContext, i, OutBufPtr);
+ }
+
+ *OutBufPtr = '\0'; // the end of the buffer
+ SendPacket(OutBuffer);
+}
+
+
+/**
+ Adds the RegNumber-th register's value to the output buffer, starting at the given OutBufPtr
+
+ @param SystemContext Register content at time of the exception
+ @param RegNumber the number of the register that we want to write
+ @param InBufPtr pointer to the output buffer. the new data will be extracted from the input buffer from this point on.
+ @retval the pointer to the next character of the input buffer that can be used
+ **/
+CHAR8 *
+BasicWriteRegister (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN UINTN RegNumber,
+ IN CHAR8 *InBufPtr
+ )
+{
+ UINTN RegSize;
+ UINTN TempValue; // the value transferred from a hex char
+ UINT32 NewValue; // the new value of the RegNumber-th Register
+
+ NewValue = 0;
+ RegSize = 0;
+ while (RegSize < REG_SIZE) {
+ TempValue = HexCharToInt(*InBufPtr++);
+
+ if (TempValue < 0) {
+ SendError (GDB_EBADMEMDATA);
+ return NULL;
+ }
+
+ NewValue += (TempValue << (RegSize+4));
+ TempValue = HexCharToInt(*InBufPtr++);
+
+ if (TempValue < 0) {
+ SendError (GDB_EBADMEMDATA);
+ return NULL;
+ }
+
+ NewValue += (TempValue << RegSize);
+ RegSize = RegSize + 8;
+ }
+ *(FindPointerToRegister(SystemContext, RegNumber)) = NewValue;
+ return InBufPtr;
+}
+
+
+/** ‘P n...=r...’
+ Writes the new value of n-th register received into the input buffer to the n-th register
+
+ @param SystemContext Register content at time of the exception
+ @param InBuffer Ponter to the input buffer received from gdb server
+ **/
+VOID
+EFIAPI
+WriteNthRegister (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN CHAR8 *InBuffer
+ )
+{
+ UINTN RegNumber;
+ CHAR8 RegNumBuffer[MAX_REG_NUM_BUF_SIZE]; // put the 'n..' part of the message into this array
+ CHAR8 *RegNumBufPtr;
+ CHAR8 *InBufPtr; // pointer to the input buffer
+
+ // find the register number to write
+ InBufPtr = &InBuffer[1];
+ RegNumBufPtr = RegNumBuffer;
+ while (*InBufPtr != '=') {
+ *RegNumBufPtr++ = *InBufPtr++;
+ }
+ *RegNumBufPtr = '\0';
+ RegNumber = AsciiStrHexToUintn (RegNumBuffer);
+
+ // check if this is a valid Register Number
+ if ((RegNumber < 0) || (RegNumber >= MaxRegisterCount())) {
+ SendError (GDB_EINVALIDREGNUM);
+ return;
+ }
+ InBufPtr++; // skips the '=' character
+ BasicWriteRegister (SystemContext, RegNumber, InBufPtr);
+ SendSuccess();
+}
+
+
+/** ‘G XX...’
+ Writes the new values received into the input buffer to the general registers
+
+ @param SystemContext Register content at time of the exception
+ @param InBuffer Pointer to the input buffer received from gdb server
+ **/
+VOID
+EFIAPI
+WriteGeneralRegisters (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN CHAR8 *InBuffer
+ )
+{
+ UINTN i;
+ CHAR8 *InBufPtr; /// pointer to the input buffer
+
+ // check to see if the buffer is the right size which is
+ // 1 (for 'G') + 16 (for 16 registers) * 8 ( for 8 hex chars each) = 129
+ if (AsciiStrLen(InBuffer) != 129) { // 16 regs, 8 hex chars each, and the end '\0' (escape seq)
+ //Bad message. Message is not the right length
+ SendError (GDB_EBADBUFSIZE);
+ return;
+ }
+
+ InBufPtr = &InBuffer[1];
+
+ // Read the new values for the registers from the input buffer to an array, NewValueArray.
+ // The values in the array are in the gdb ordering
+ for(i=0; i < MaxRegisterCount(); i++) { // there are only 16 registers to write
+ InBufPtr = BasicWriteRegister(SystemContext, i, InBufPtr);
+ }
+
+ SendSuccess();
+}
+
+
+/**
+ Insert Single Step in the SystemContext
+
+ @param SystemContext Register content at time of the exception
+ **/
+VOID
+AddSingleStep (
+ IN EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ SystemContext.SystemContextIa32->Eflags |= TF_BIT; //Setting the TF bit.
+}
+
+
+/**
+ Remove Single Step in the SystemContext
+
+ @param SystemContext Register content at time of the exception
+ **/
+VOID
+RemoveSingleStep (
+ IN EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ SystemContext.SystemContextIa32->Eflags &= ~TF_BIT; // clearing the TF bit.
+}
+
+
+
+/** ‘c [addr ]’
+ Continue. addr is Address to resume. If addr is omitted, resume at current
+ Address.
+
+ @param SystemContext Register content at time of the exception
+ **/
+VOID
+EFIAPI
+ContinueAtAddress (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN CHAR8 *PacketData
+ )
+{
+ if (PacketData[1] != '\0') {
+ SystemContext.SystemContextIa32->Eip = AsciiStrHexToUintn (&PacketData[1]);
+ }
+}
+
+
+/** ‘s [addr ]’
+ Single step. addr is the Address at which to resume. If addr is omitted, resume
+ at same Address.
+
+ @param SystemContext Register content at time of the exception
+ **/
+VOID
+EFIAPI
+SingleStep (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN CHAR8 *PacketData
+ )
+{
+ if (PacketData[1] != '\0') {
+ SystemContext.SystemContextIa32->Eip = AsciiStrHexToUintn (&PacketData[1]);
+ }
+
+ AddSingleStep (SystemContext);
+}
+
+
+/**
+ Returns breakpoint data address from DR0-DR3 based on the input breakpoint number
+
+ @param SystemContext Register content at time of the exception
+ @param BreakpointNumber Breakpoint number
+
+ @retval Address Data address from DR0-DR3 based on the breakpoint number.
+
+**/
+UINTN
+GetBreakpointDataAddress (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN UINTN BreakpointNumber
+ )
+{
+ UINTN Address;
+
+ if (BreakpointNumber == 1) {
+ Address = SystemContext.SystemContextIa32->Dr0;
+ } else if (BreakpointNumber == 2) {
+ Address = SystemContext.SystemContextIa32->Dr1;
+ } else if (BreakpointNumber == 3) {
+ Address = SystemContext.SystemContextIa32->Dr2;
+ } else if (BreakpointNumber == 4) {
+ Address = SystemContext.SystemContextIa32->Dr3;
+ } else {
+ Address = 0;
+ }
+
+ return Address;
+}
+
+
+/**
+ Returns currently detected breakpoint value based on the register DR6 B0-B3 field.
+ If no breakpoint is detected then it returns 0.
+
+ @param SystemContext Register content at time of the exception
+
+ @retval {1-4} Currently detected breakpoint value
+ @retval 0 No breakpoint detected.
+
+**/
+UINTN
+GetBreakpointDetected (
+ IN EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ IA32_DR6 Dr6;
+ UINTN BreakpointNumber;
+
+ Dr6.UintN = SystemContext.SystemContextIa32->Dr6;
+
+ if (Dr6.Bits.B0 == 1) {
+ BreakpointNumber = 1;
+ } else if (Dr6.Bits.B1 == 1) {
+ BreakpointNumber = 2;
+ } else if (Dr6.Bits.B2 == 1) {
+ BreakpointNumber = 3;
+ } else if (Dr6.Bits.B3 == 1) {
+ BreakpointNumber = 4;
+ } else {
+ BreakpointNumber = 0; //No breakpoint detected
+ }
+
+ return BreakpointNumber;
+}
+
+
+/**
+ Returns Breakpoint type (InstructionExecution, DataWrite, DataRead or DataReadWrite)
+ based on the Breakpoint number
+
+ @param SystemContext Register content at time of the exception
+ @param BreakpointNumber Breakpoint number
+
+ @retval BREAK_TYPE Breakpoint type value read from register DR7 RWn field
+ For unknown value, it returns NotSupported.
+
+**/
+BREAK_TYPE
+GetBreakpointType (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN UINTN BreakpointNumber
+ )
+{
+ IA32_DR7 Dr7;
+ BREAK_TYPE Type = NotSupported; //Default is NotSupported type
+
+ Dr7.UintN = SystemContext.SystemContextIa32->Dr7;
+
+ if (BreakpointNumber == 1) {
+ Type = (BREAK_TYPE) Dr7.Bits.RW0;
+ } else if (BreakpointNumber == 2) {
+ Type = (BREAK_TYPE) Dr7.Bits.RW1;
+ } else if (BreakpointNumber == 3) {
+ Type = (BREAK_TYPE) Dr7.Bits.RW2;
+ } else if (BreakpointNumber == 4) {
+ Type = (BREAK_TYPE) Dr7.Bits.RW3;
+ }
+
+ return Type;
+}
+
+
+/**
+ Parses Length and returns the length which DR7 LENn field accepts.
+ For example: If we receive 1-Byte length then we should return 0.
+ Zero gets written to DR7 LENn field.
+
+ @param Length Breakpoint length in Bytes (1 byte, 2 byte, 4 byte)
+
+ @retval Length Appropriate converted values which DR7 LENn field accepts.
+
+**/
+UINTN
+ConvertLengthData (
+ IN UINTN Length
+ )
+{
+ if (Length == 1) { //1-Byte length
+ return 0;
+ } else if (Length == 2) { //2-Byte length
+ return 1;
+ } else if (Length == 4) { //4-Byte length
+ return 3;
+ } else { //Undefined or 8-byte length
+ return 2;
+ }
+}
+
+
+/**
+ Finds the next free debug register. If all the registers are occupied then
+ EFI_OUT_OF_RESOURCES is returned.
+
+ @param SystemContext Register content at time of the exception
+ @param Register Register value (0 - 3 for the first free debug register)
+
+ @retval EFI_STATUS Appropriate status value.
+
+**/
+EFI_STATUS
+FindNextFreeDebugRegister (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ OUT UINTN *Register
+ )
+{
+ IA32_DR7 Dr7;
+
+ Dr7.UintN = SystemContext.SystemContextIa32->Dr7;
+
+ if (Dr7.Bits.G0 == 0) {
+ *Register = 0;
+ } else if (Dr7.Bits.G1 == 0) {
+ *Register = 1;
+ } else if (Dr7.Bits.G2 == 0) {
+ *Register = 2;
+ } else if (Dr7.Bits.G3 == 0) {
+ *Register = 3;
+ } else {
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ return EFI_SUCCESS;
+}
+
+
+/**
+ Enables the debug register. Writes Address value to appropriate DR0-3 register.
+ Sets LENn, Gn, RWn bits in DR7 register.
+
+ @param SystemContext Register content at time of the exception
+ @param Register Register value (0 - 3)
+ @param Address Breakpoint address value
+ @param Type Breakpoint type (Instruction, Data write, Data read
+ or write etc.)
+
+ @retval EFI_STATUS Appropriate status value.
+
+**/
+EFI_STATUS
+EnableDebugRegister (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN UINTN Register,
+ IN UINTN Address,
+ IN UINTN Length,
+ IN UINTN Type
+ )
+{
+ IA32_DR7 Dr7;
+
+ //Convert length data
+ Length = ConvertLengthData (Length);
+
+ //For Instruction execution, length should be 0
+ //(Ref. Intel reference manual 18.2.4)
+ if ((Type == 0) && (Length != 0)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //Hardware doesn't support ReadWatch (z3 packet) type. GDB can handle
+ //software breakpoint. We should send empty packet in both these cases.
+ if ((Type == (BREAK_TYPE)DataRead) ||
+ (Type == (BREAK_TYPE)SoftwareBreakpoint)) {
+ return EFI_UNSUPPORTED;
+ }
+
+ //Read DR7 so appropriate Gn, RWn and LENn bits can be modified.
+ Dr7.UintN = SystemContext.SystemContextIa32->Dr7;
+
+ if (Register == 0) {
+ SystemContext.SystemContextIa32->Dr0 = Address;
+ Dr7.Bits.G0 = 1;
+ Dr7.Bits.RW0 = Type;
+ Dr7.Bits.LEN0 = Length;
+ } else if (Register == 1) {
+ SystemContext.SystemContextIa32->Dr1 = Address;
+ Dr7.Bits.G1 = 1;
+ Dr7.Bits.RW1 = Type;
+ Dr7.Bits.LEN1 = Length;
+ } else if (Register == 2) {
+ SystemContext.SystemContextIa32->Dr2 = Address;
+ Dr7.Bits.G2 = 1;
+ Dr7.Bits.RW2 = Type;
+ Dr7.Bits.LEN2 = Length;
+ } else if (Register == 3) {
+ SystemContext.SystemContextIa32->Dr3 = Address;
+ Dr7.Bits.G3 = 1;
+ Dr7.Bits.RW3 = Type;
+ Dr7.Bits.LEN3 = Length;
+ } else {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //Update Dr7 with appropriate Gn, RWn and LENn bits
+ SystemContext.SystemContextIa32->Dr7 = Dr7.UintN;
+
+ return EFI_SUCCESS;
+}
+
+
+/**
+ Returns register number 0 - 3 for the maching debug register.
+ This function compares incoming Address, Type, Length and
+ if there is a match then it returns the appropriate register number.
+ In case of mismatch, function returns EFI_NOT_FOUND message.
+
+ @param SystemContext Register content at time of the exception
+ @param Address Breakpoint address value
+ @param Length Breakpoint length value
+ @param Type Breakpoint type (Instruction, Data write,
+ Data read or write etc.)
+ @param Register Register value to be returned
+
+ @retval EFI_STATUS Appropriate status value.
+
+**/
+EFI_STATUS
+FindMatchingDebugRegister (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN UINTN Address,
+ IN UINTN Length,
+ IN UINTN Type,
+ OUT UINTN *Register
+ )
+{
+ IA32_DR7 Dr7;
+
+ //Hardware doesn't support ReadWatch (z3 packet) type. GDB can handle
+ //software breakpoint. We should send empty packet in both these cases.
+ if ((Type == (BREAK_TYPE)DataRead) ||
+ (Type == (BREAK_TYPE)SoftwareBreakpoint)) {
+ return EFI_UNSUPPORTED;
+ }
+
+ //Convert length data
+ Length = ConvertLengthData(Length);
+
+ Dr7.UintN = SystemContext.SystemContextIa32->Dr7;
+
+ if ((Dr7.Bits.G0 == 1) &&
+ (Dr7.Bits.LEN0 == Length) &&
+ (Dr7.Bits.RW0 == Type) &&
+ (Address == SystemContext.SystemContextIa32->Dr0)) {
+ *Register = 0;
+ } else if ((Dr7.Bits.G1 == 1) &&
+ (Dr7.Bits.LEN1 == Length) &&
+ (Dr7.Bits.RW1 == Type) &&
+ (Address == SystemContext.SystemContextIa32->Dr1)) {
+ *Register = 1;
+ } else if ((Dr7.Bits.G2 == 1) &&
+ (Dr7.Bits.LEN2 == Length) &&
+ (Dr7.Bits.RW2 == Type) &&
+ (Address == SystemContext.SystemContextIa32->Dr2)) {
+ *Register = 2;
+ } else if ((Dr7.Bits.G3 == 1) &&
+ (Dr7.Bits.LEN3 == Length) &&
+ (Dr7.Bits.RW3 == Type) &&
+ (Address == SystemContext.SystemContextIa32->Dr3)) {
+ *Register = 3;
+ } else {
+ Print ((CHAR16 *)L"No match found..\n");
+ return EFI_NOT_FOUND;
+ }
+
+ return EFI_SUCCESS;
+}
+
+
+/**
+ Disables the particular debug register.
+
+ @param SystemContext Register content at time of the exception
+ @param Register Register to be disabled
+
+ @retval EFI_STATUS Appropriate status value.
+
+**/
+EFI_STATUS
+DisableDebugRegister (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN UINTN Register
+ )
+{
+ IA32_DR7 Dr7;
+ UINTN Address = 0;
+
+ //Read DR7 register so appropriate Gn, RWn and LENn bits can be turned off.
+ Dr7.UintN = SystemContext.SystemContextIa32->Dr7;
+
+ if (Register == 0) {
+ SystemContext.SystemContextIa32->Dr0 = Address;
+ Dr7.Bits.G0 = 0;
+ Dr7.Bits.RW0 = 0;
+ Dr7.Bits.LEN0 = 0;
+ } else if (Register == 1) {
+ SystemContext.SystemContextIa32->Dr1 = Address;
+ Dr7.Bits.G1 = 0;
+ Dr7.Bits.RW1 = 0;
+ Dr7.Bits.LEN1 = 0;
+ } else if (Register == 2) {
+ SystemContext.SystemContextIa32->Dr2 = Address;
+ Dr7.Bits.G2 = 0;
+ Dr7.Bits.RW2 = 0;
+ Dr7.Bits.LEN2 = 0;
+ } else if (Register == 3) {
+ SystemContext.SystemContextIa32->Dr3 = Address;
+ Dr7.Bits.G3 = 0;
+ Dr7.Bits.RW3 = 0;
+ Dr7.Bits.LEN3 = 0;
+ } else {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //Update DR7 register so appropriate Gn, RWn and LENn bits can be turned off.
+ SystemContext.SystemContextIa32->Dr7 = Dr7.UintN;
+
+ return EFI_SUCCESS;
+}
+
+
+/**
+ ‘Z1, [addr], [length]’
+ ‘Z2, [addr], [length]’
+ ‘Z3, [addr], [length]’
+ ‘Z4, [addr], [length]’
+
+ Insert hardware breakpoint/watchpoint at address addr of size length
+
+ @param SystemContext Register content at time of the exception
+ @param *PacketData Pointer to the Payload data for the packet
+
+**/
+VOID
+EFIAPI
+InsertBreakPoint (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN CHAR8 *PacketData
+ )
+{
+ UINTN Type;
+ UINTN Address;
+ UINTN Length;
+ UINTN Register;
+ EFI_STATUS Status;
+ BREAK_TYPE BreakType = NotSupported;
+ UINTN ErrorCode;
+
+ ErrorCode = ParseBreakpointPacket (PacketData, &Type, &Address, &Length);
+ if (ErrorCode > 0) {
+ SendError ((UINT8)ErrorCode);
+ return;
+ }
+
+ switch (Type) {
+
+ case 0: //Software breakpoint
+ BreakType = SoftwareBreakpoint;
+ break;
+
+ case 1: //Hardware breakpoint
+ BreakType = InstructionExecution;
+ break;
+
+ case 2: //Write watchpoint
+ BreakType = DataWrite;
+ break;
+
+ case 3: //Read watchpoint
+ BreakType = DataRead;
+ break;
+
+ case 4: //Access watchpoint
+ BreakType = DataReadWrite;
+ break;
+
+ default :
+ Print ((CHAR16 *)L"Insert breakpoint default: %x\n", Type);
+ SendError (GDB_EINVALIDBRKPOINTTYPE);
+ return;
+ }
+
+ // Find next free debug register
+ Status = FindNextFreeDebugRegister (SystemContext, &Register);
+ if (EFI_ERROR(Status)) {
+ Print ((CHAR16 *)L"No space left on device\n");
+ SendError (GDB_ENOSPACE);
+ return;
+ }
+
+ // Write Address, length data at particular DR register
+ Status = EnableDebugRegister (SystemContext, Register, Address, Length, (UINTN)BreakType);
+ if (EFI_ERROR(Status)) {
+
+ if (Status == EFI_UNSUPPORTED) {
+ Print ((CHAR16 *)L"Not supported\n");
+ SendNotSupported();
+ return;
+ }
+
+ Print ((CHAR16 *)L"Invalid argument\n");
+ SendError (GDB_EINVALIDARG);
+ return;
+ }
+
+ SendSuccess ();
+}
+
+
+/**
+ ‘z1, [addr], [length]’
+ ‘z2, [addr], [length]’
+ ‘z3, [addr], [length]’
+ ‘z4, [addr], [length]’
+
+ Remove hardware breakpoint/watchpoint at address addr of size length
+
+ @param *PacketData Pointer to the Payload data for the packet
+
+**/
+VOID
+EFIAPI
+RemoveBreakPoint (
+ IN EFI_SYSTEM_CONTEXT SystemContext,
+ IN CHAR8 *PacketData
+ )
+{
+ UINTN Type;
+ UINTN Address;
+ UINTN Length;
+ UINTN Register;
+ BREAK_TYPE BreakType = NotSupported;
+ EFI_STATUS Status;
+ UINTN ErrorCode;
+
+ //Parse breakpoint packet data
+ ErrorCode = ParseBreakpointPacket (PacketData, &Type, &Address, &Length);
+ if (ErrorCode > 0) {
+ SendError ((UINT8)ErrorCode);
+ return;
+ }
+
+ switch (Type) {
+
+ case 0: //Software breakpoint
+ BreakType = SoftwareBreakpoint;
+ break;
+
+ case 1: //Hardware breakpoint
+ BreakType = InstructionExecution;
+ break;
+
+ case 2: //Write watchpoint
+ BreakType = DataWrite;
+ break;
+
+ case 3: //Read watchpoint
+ BreakType = DataRead;
+ break;
+
+ case 4: //Access watchpoint
+ BreakType = DataReadWrite;
+ break;
+
+ default :
+ SendError (GDB_EINVALIDBRKPOINTTYPE);
+ return;
+ }
+
+ //Find matching debug register
+ Status = FindMatchingDebugRegister (SystemContext, Address, Length, (UINTN)BreakType, &Register);
+ if (EFI_ERROR(Status)) {
+
+ if (Status == EFI_UNSUPPORTED) {
+ Print ((CHAR16 *)L"Not supported.\n");
+ SendNotSupported();
+ return;
+ }
+
+ Print ((CHAR16 *)L"No matching register found.\n");
+ SendError (GDB_ENOSPACE);
+ return;
+ }
+
+ //Remove breakpoint
+ Status = DisableDebugRegister(SystemContext, Register);
+ if (EFI_ERROR(Status)) {
+ Print ((CHAR16 *)L"Invalid argument.\n");
+ SendError (GDB_EINVALIDARG);
+ return;
+ }
+
+ SendSuccess ();
+}
+
+
+VOID
+InitializeProcessor (
+ VOID
+ )
+{
+}
+
+BOOLEAN
+ValidateAddress (
+ IN VOID *Address
+ )
+{
+ return TRUE;
+}
+
+BOOLEAN
+ValidateException (
+ IN EFI_EXCEPTION_TYPE ExceptionType,
+ IN OUT EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ return TRUE;
+}
+