/** @file
Processor specific parts of the GDB stub
Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#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 Pointer 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 matching 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;
}