792 lines
25 KiB
C++
792 lines
25 KiB
C++
//////////////////////////////////////////////////////////////////////////////
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//
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// Microsoft Research Singularity
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//
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// Copyright (c) Microsoft Corporation. All rights reserved.
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//
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// File: halkdserial.cpp: Serial-port transport routines.
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//
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// Note: Kernel Only
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//
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#include "hal.h"
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#include "halkd.h"
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//
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// Debugger Debugging
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//
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#define KDDBG if (0) kdprintf
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#define KDDBG2 if (0) kdprintf
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//
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// Globals
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//
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static UINT32 KdCompPacketIdExpected = INITIAL_PACKET_ID;
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static UINT32 KdCompNextPacketIdToSend = INITIAL_PACKET_ID | SYNC_PACKET_ID;
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static BOOL KdStateChange64Sent = false;
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/////////////////////////////////////////////////////////////////////////////
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/////////////////////////////////////////////////////////////////////////////
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//
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// PLATFORM LAYER - this is the cut point for abstracting the serial port
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//
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/////////////////////////////////////////////////////////////////////////////
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/////////////////////////////////////////////////////////////////////////////
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KDP_STATUS KdpSerialGetByte(OUT PUCHAR Input, BOOL WaitForByte);
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void KdpSerialPutByte(IN UCHAR Output);
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//++
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//
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//Routine Description:
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//
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// This routine reads a string from the kernel debugger port.
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//
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//Arguments:
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//
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// Destination - Supplies a pointer to the input string.
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//
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// Length - Supplies the length of the string to be read.
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//--
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static KDP_STATUS KdpSerialReceiveString(OUT PUCHAR Destination, IN UINT32 Length, IN BOOL WaitForInput = true)
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{
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KDDBG2("KdpSerialReceiveString len %d\n", Length);
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UCHAR Input;
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UINT32 ReqLength = Length;
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UINT32 ReturnCode;
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//
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// Read bytes until either a error is encountered or the entire string
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// has been read.
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//
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while (Length > 0) {
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KdpSpin();
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ReturnCode = KdpSerialGetByte(&Input, WaitForInput);
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if (ReturnCode != KDP_PACKET_RECEIVED) {
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break;
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}
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else {
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*Destination++ = Input;
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Length -= 1;
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}
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}
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KDDBG2("KdpSerialReceiveString left %d\n", Length);
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return (Length == 0) ? KDP_PACKET_RECEIVED : KDP_PACKET_TIMEOUT;
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}
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//++
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//
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//Routine Description:
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//
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// This routine writes a string to the kernel debugger port.
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//
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//Arguments:
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//
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// Source - Supplies a pointer to the output string.
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//
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// Length - Supplies the length of the string to be written.
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//
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//Return Value:
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//
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// None.
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//
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//--
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static void KdpSerialSendString(IN PUCHAR Source, IN UINT32 Length)
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{
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KDDBG2("KdpSerialSendString len %d\n", Length);
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UINT32 ReqLength = (UINT32)Length;
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//
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// Write bytes to the kernel debugger port.
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//
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UCHAR Output;
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while (Length > 0) {
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Output = *Source++;
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KdpSerialPutByte(Output);
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Length -= 1;
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}
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KDDBG2("KdpSerialSendString done\n");
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}
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/////////////////////////////////////////////////////////////////////////////
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/////////////////////////////////////////////////////////////////////////////
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//
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// CHANNEL LAYER - all this code should be neutral to the actual channel
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// (i.e. nothing specific to serial port, only reading and writing bytes)
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//
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/////////////////////////////////////////////////////////////////////////////
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/////////////////////////////////////////////////////////////////////////////
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// Wait for a packet header leader (receive it into PacketLeader ULONG).
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//
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static
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KDP_STATUS
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KdCompReceivePacketLeader(
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OUT UINT32 *PacketLeader,
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IN OUT PKD_CONTEXT KdContext
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)
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{
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UCHAR Input;
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UCHAR PreviousByte = 0;
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UINT32 PacketId = 0;
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UINT32 Index;
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KDP_STATUS ReturnCode;
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BOOLEAN BreakinDetected = false;
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KDDBG2("KdCompReceivePacketLeader\n");
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//
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// NOTE - With all the interrupts being off, it is very hard
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// to implement the actual timeout code. (Maybe, by reading the CMOS.)
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// Here we use a loop count to wait about 3 seconds. The CpGetByte
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// will return with error code = KDP_PACKET_TIMEOUT if it cannot find data
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// byte within 1 second. Kernel debugger's timeout period is 5 seconds.
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//
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Index = 0;
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do {
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ReturnCode = KdpSerialReceiveString(&Input, 1);
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if (ReturnCode == KDP_PACKET_TIMEOUT) {
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if (BreakinDetected) {
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KdContext->KdpControlCPending = true;
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return KDP_PACKET_RESEND;
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}
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else {
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KDDBG2("KdCompReceivePackerLeader returning KDP_PACKET_TIMEOUT\n");
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return KDP_PACKET_TIMEOUT;
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}
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}
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else if (ReturnCode == KDP_PACKET_RESEND) {
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Index = 0;
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continue;
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}
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else { // if (ReturnCode == KDP_PACKET_RECEIVED)
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if ( Input == PACKET_LEADER_BYTE ||
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Input == CONTROL_PACKET_LEADER_BYTE ) {
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if ( Index == 0 ) {
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PreviousByte = Input;
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Index++;
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}
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else if (Input == PreviousByte) {
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Index++;
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}
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else {
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PreviousByte = Input;
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Index = 1;
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}
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}
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else {
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//
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// If we detect breakin character, we need to verify it
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// validity. (It is possible that we missed a packet leader
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// and the breakin character is simply a data byte in the
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// packet.)
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// Since kernel debugger send out breakin character ONLY
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// when it is waiting for State Change packet. The breakin
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// character should not be followed by any other character
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// except packet leader byte.
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//
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if ( Input == BREAKIN_PACKET_BYTE ) {
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BreakinDetected = true;
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}
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else {
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//
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// The following statement is ABSOLUTELY necessary.
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//
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BreakinDetected = false;
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}
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Index = 0;
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}
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}
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} while ( Index < 4 );
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if (BreakinDetected) {
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KdContext->KdpControlCPending = true;
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}
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//
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// return the packet leader and false to indicate no resend is needed.
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//
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if ( Input == PACKET_LEADER_BYTE ) {
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*PacketLeader = PACKET_LEADER;
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}
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else {
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*PacketLeader = CONTROL_PACKET_LEADER;
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}
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KdDebuggerNotPresent = false;
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#if 0
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SharedUserData->KdDebuggerEnabled |= 0x00000002;
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#endif
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return KDP_PACKET_RECEIVED;
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}
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static
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void
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KdpSendControlPacket(
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IN UINT16 PacketType,
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IN UINT32 PacketId OPTIONAL
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)
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// Routine Description:
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// This routine sends a control packet to the host machine that is running the
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// kernel debugger and waits for an ACK.
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//
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// Arguments:
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// PacketType - Supplies the type of packet to send.
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// PacketId - Supplies packet id, optionally.
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//
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// Return Value:
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// None.
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{
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KD_PACKET PacketHeader;
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//
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// Initialize and send the packet header.
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//
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PacketHeader.PacketLeader = CONTROL_PACKET_LEADER;
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if (PacketId != 0) {
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PacketHeader.PacketId = PacketId;
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}
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PacketHeader.ByteCount = 0;
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PacketHeader.Checksum = 0;
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PacketHeader.PacketType = PacketType;
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KdpSerialSendString((PUCHAR)&PacketHeader, sizeof(KD_PACKET));
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return;
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}
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//////////////////////////////////////////////////////////////////////////////
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//
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void
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KdpSerialSendPacket(
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IN UINT32 PacketType,
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IN PSTRING MessageHeader,
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IN PSTRING MessageData OPTIONAL,
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IN OUT PKD_CONTEXT KdContext
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)
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// Routine Description:
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// This routine sends a packet to the host machine that is running the
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// kernel debugger and waits for an ACK.
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//
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// Arguments:
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// PacketType - Supplies the type of packet to send.
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// MessageHeader - Supplies a pointer to a string descriptor that describes
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// the message information.
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// MessageData - Supplies a pointer to a string descriptor that describes
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// the optional message data.
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// KdContext - Supplies a pointer to the kernel debugger context.
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//
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// Return Value:
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// None.
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{
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KD_PACKET PacketHeader;
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UINT32 MessageDataLength;
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KDP_STATUS ReturnCode;
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KDDBG2("KdpSerialSendPacket %d\n", PacketType);
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if (MessageData != NULL) {
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MessageDataLength = MessageData->Length;
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PacketHeader.Checksum = KdpComputeChecksum(MessageData->Buffer,
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MessageData->Length);
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}
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else {
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MessageDataLength = 0;
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PacketHeader.Checksum = 0;
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}
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PacketHeader.Checksum += KdpComputeChecksum(MessageHeader->Buffer,
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MessageHeader->Length);
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//
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// Initialize and send the packet header.
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//
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PacketHeader.PacketLeader = PACKET_LEADER;
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PacketHeader.ByteCount = (UINT16)(MessageHeader->Length + MessageDataLength);
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PacketHeader.PacketType = (UINT16)PacketType;
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KdCompNumberRetries = KdCompRetryCount;
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//
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// We sync on first STATE_CHANGE64 message like NT. If this
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// is the first such message, drain receive pipe as nothing
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// said before this instant is interesting (and any buffered
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// packets may interact badly with SendWaitContinue).
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//
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if (PacketType == PACKET_TYPE_KD_STATE_CHANGE64 && !KdStateChange64Sent) {
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//
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UCHAR uDummy;
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uint32 dwDrained = 0;
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KdCompNextPacketIdToSend |= SYNC_PACKET_ID;
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KdStateChange64Sent = true;
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while (KdpSerialReceiveString(&uDummy, 1, false) == KDP_PACKET_RECEIVED) {
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dwDrained++;
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}
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}
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do {
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KDDBG2("LOOP %d/%d\n", KdCompNumberRetries, KdCompRetryCount);
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if (KdCompNumberRetries == 0) {
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KDDBG("KdCompNumberRetries == 0\n");
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//
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// If the packet is not for reporting exception, we give up
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// and declare debugger not present.
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//
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if (PacketType == PACKET_TYPE_KD_STATE_CHANGE64) {
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PDBGKD_ANY_WAIT_STATE_CHANGE StateChange
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= (PDBGKD_ANY_WAIT_STATE_CHANGE)MessageHeader->Buffer;
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if (StateChange->NewState == DbgKdLoadSymbolsStateChange) {
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KdDebuggerNotPresent = true;
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//SharedUserData->KdDebuggerEnabled &= ~0x00000002;
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KdCompNextPacketIdToSend = INITIAL_PACKET_ID | SYNC_PACKET_ID;
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KdCompPacketIdExpected = INITIAL_PACKET_ID;
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return;
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}
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}
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else if (PacketType == PACKET_TYPE_KD_DEBUG_IO) {
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PDBGKD_DEBUG_IO DebugIo
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= (PDBGKD_DEBUG_IO)MessageHeader->Buffer;
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if (DebugIo->ApiNumber == DbgKdPrintStringApi) {
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KdDebuggerNotPresent = true;
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//SharedUserData->KdDebuggerEnabled &= ~0x00000002;
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KdCompNextPacketIdToSend = INITIAL_PACKET_ID | SYNC_PACKET_ID;
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KdCompPacketIdExpected = INITIAL_PACKET_ID;
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return;
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}
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}
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else if (PacketType == PACKET_TYPE_KD_FILE_IO) {
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PDBGKD_FILE_IO FileIo;
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FileIo = (PDBGKD_FILE_IO)MessageHeader->Buffer;
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if (FileIo->ApiNumber == DbgKdCreateFileApi) {
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KdDebuggerNotPresent = true;
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//SharedUserData->KdDebuggerEnabled &= ~0x00000002;
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KdCompNextPacketIdToSend = INITIAL_PACKET_ID | SYNC_PACKET_ID;
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KdCompPacketIdExpected = INITIAL_PACKET_ID;
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return;
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}
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}
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}
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//
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// Setting PacketId has to be in the do loop in case Packet Id was
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// reset.
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//
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PacketHeader.PacketId = KdCompNextPacketIdToSend;
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KdpSerialSendString((PUCHAR)&PacketHeader, sizeof(KD_PACKET));
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//
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// Output message header.
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//
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KdpSerialSendString((PUCHAR)MessageHeader->Buffer, MessageHeader->Length);
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//
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// Output message data.
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//
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if ( MessageDataLength ) {
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KdpSerialSendString((PUCHAR)MessageData->Buffer, MessageData->Length);
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}
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//
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// Output a packet trailing byte
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//
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{
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UCHAR b = PACKET_TRAILING_BYTE;
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KdpSerialSendString(&b, 1);
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}
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//
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// Wait for the Ack Packet
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//
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ReturnCode = KdpSerialReceivePacket(
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PACKET_TYPE_KD_ACKNOWLEDGE,
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NULL,
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NULL,
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NULL,
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KdContext
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);
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if (ReturnCode == KDP_PACKET_TIMEOUT) {
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KDDBG2("TIMEOUT\n");
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KdCompNumberRetries--;
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}
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} while (ReturnCode != KDP_PACKET_RECEIVED);
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KDDBG2("KD: PACKET_RECEIVED\n");
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//
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// Reset Sync bit in packet id. The packet we sent may have Sync bit set
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//
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KdCompNextPacketIdToSend &= ~SYNC_PACKET_ID;
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//
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// Since we are able to talk to debugger, the retrycount is set to
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// maximum value.
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//
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KdCompRetryCount = KdContext->KdpDefaultRetries;
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KDDBG2("KdpSerialSendPacket %d done\n", PacketType);
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}
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//////////////////////////////////////////////////////////////////////////////
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//
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KDP_STATUS
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KdpSerialReceivePacket(
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IN UINT32 PacketType,
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OUT PSTRING MessageHeader,
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OUT PSTRING MessageData,
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OUT UINT32 *DataLength,
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IN OUT PKD_CONTEXT KdContext
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)
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// Routine Description:
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// This routine receives a packet from the host machine that is running
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// the kernel debugger UI. This routine is ALWAYS called after packet being
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// sent by caller. It first waits for ACK packet for the packet sent and
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// then waits for the packet desired.
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//
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// N.B. If caller is KdPrintString, the parameter PacketType is
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// PACKET_TYPE_KD_ACKNOWLEDGE. In this case, this routine will return
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// right after the ack packet is received.
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//
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// Arguments:
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// PacketType - Supplies the type of packet that is excepted.
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// MessageHeader - Supplies a pointer to a string descriptor for the input
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// message.
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// MessageData - Supplies a pointer to a string descriptor for the input data.
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// DataLength - Supplies pointer to UINT32 to receive length of recv. data.
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// KdContext - Supplies a pointer to the kernel debugger context.
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//
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// Return Value:
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// KDP_PACKET_RESEND - if resend is required.
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// KDP_PAKCET_TIMEOUT - if timeout.
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// KDP_PACKET_RECEIVED - if packet received.
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{
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UCHAR Input;
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UINT32 MessageLength;
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KD_PACKET PacketHeader;
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KDP_STATUS ReturnCode;
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UINT32 Checksum;
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KDDBG2("KdpSerialReceivePacket %d\n", PacketType);
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WaitForPacketLeader:
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//
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// Read Packet Leader
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//
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ReturnCode = KdCompReceivePacketLeader(&PacketHeader.PacketLeader, KdContext);
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KDDBG2("KdCompReceivePacketLeader returned %d\n", ReturnCode);
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//
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// If we can successfully read packet leader, it has high possibility that
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// kernel debugger is alive. So reset count.
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//
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if (ReturnCode != KDP_PACKET_TIMEOUT) {
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KdCompNumberRetries = KdCompRetryCount;
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}
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if (ReturnCode != KDP_PACKET_RECEIVED) {
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return ReturnCode;
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}
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//
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// Read packet type.
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//
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ReturnCode = KdpSerialReceiveString((PUCHAR)&PacketHeader.PacketType,
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sizeof(PacketHeader.PacketType));
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if (ReturnCode == KDP_PACKET_TIMEOUT) {
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return KDP_PACKET_TIMEOUT;
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}
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else if (ReturnCode == KDP_PACKET_RESEND) {
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if (PacketHeader.PacketLeader == CONTROL_PACKET_LEADER) {
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//
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// If read error and it is for a control packet, simply
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// pretend that we have not seen this packet. Hopefully
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// we will receive the packet we desire which automatically acks
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// the packet we just sent.
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//
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goto WaitForPacketLeader;
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}
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else {
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//
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// if read error while reading data packet, we have to ask
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// kernel debugger to resend us the packet.
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//
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goto SendResendPacket;
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}
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}
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//
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// if the packet we received is a resend request, we return true and
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// let caller resend the packet.
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//
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if ( PacketHeader.PacketLeader == CONTROL_PACKET_LEADER &&
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PacketHeader.PacketType == PACKET_TYPE_KD_RESEND ) {
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return KDP_PACKET_RESEND;
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}
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//
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// Read data length.
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//
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ReturnCode = KdpSerialReceiveString((PUCHAR)&PacketHeader.ByteCount,
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sizeof(PacketHeader.ByteCount));
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if (ReturnCode == KDP_PACKET_TIMEOUT) {
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return KDP_PACKET_TIMEOUT;
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}
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else if (ReturnCode == KDP_PACKET_RESEND) {
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if (PacketHeader.PacketLeader == CONTROL_PACKET_LEADER) {
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goto WaitForPacketLeader;
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}
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else {
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goto SendResendPacket;
|
|
}
|
|
}
|
|
|
|
//
|
|
// Read Packet Id.
|
|
//
|
|
ReturnCode = KdpSerialReceiveString((PUCHAR)&PacketHeader.PacketId,
|
|
sizeof(PacketHeader.PacketId));
|
|
|
|
if (ReturnCode == KDP_PACKET_TIMEOUT) {
|
|
return KDP_PACKET_TIMEOUT;
|
|
}
|
|
else if (ReturnCode == KDP_PACKET_RESEND) {
|
|
if (PacketHeader.PacketLeader == CONTROL_PACKET_LEADER) {
|
|
goto WaitForPacketLeader;
|
|
}
|
|
else {
|
|
goto SendResendPacket;
|
|
}
|
|
}
|
|
|
|
//
|
|
// Read packet checksum.
|
|
//
|
|
ReturnCode = KdpSerialReceiveString((PUCHAR)&PacketHeader.Checksum,
|
|
sizeof(PacketHeader.Checksum));
|
|
if (ReturnCode == KDP_PACKET_TIMEOUT) {
|
|
return KDP_PACKET_TIMEOUT;
|
|
}
|
|
else if (ReturnCode == KDP_PACKET_RESEND) {
|
|
if (PacketHeader.PacketLeader == CONTROL_PACKET_LEADER) {
|
|
goto WaitForPacketLeader;
|
|
}
|
|
else {
|
|
goto SendResendPacket;
|
|
}
|
|
}
|
|
|
|
//
|
|
// A complete packet header is received. Check its validity and
|
|
// perform appropriate action depending on packet type.
|
|
//
|
|
if (PacketHeader.PacketLeader == CONTROL_PACKET_LEADER ) {
|
|
if (PacketHeader.PacketType == PACKET_TYPE_KD_ACKNOWLEDGE ) {
|
|
//
|
|
// If we received an expected ACK packet and we are not
|
|
// waiting for any new packet, update outgoing packet id
|
|
// and return. If we are NOT waiting for ACK packet
|
|
// we will keep on waiting. If the ACK packet
|
|
// is not for the packet we send, ignore it and keep on waiting.
|
|
//
|
|
if (PacketHeader.PacketId !=
|
|
(KdCompNextPacketIdToSend & ~SYNC_PACKET_ID)) {
|
|
goto WaitForPacketLeader;
|
|
}
|
|
else if (PacketType == PACKET_TYPE_KD_ACKNOWLEDGE) {
|
|
KdCompNextPacketIdToSend ^= 1;
|
|
return KDP_PACKET_RECEIVED;
|
|
} else {
|
|
goto WaitForPacketLeader;
|
|
}
|
|
}
|
|
else if (PacketHeader.PacketType == PACKET_TYPE_KD_RESET) {
|
|
//
|
|
// if we received Reset packet, reset the packet control variables
|
|
// and resend earlier packet.
|
|
//
|
|
KdCompNextPacketIdToSend = INITIAL_PACKET_ID;
|
|
KdCompPacketIdExpected = INITIAL_PACKET_ID;
|
|
KdpSendControlPacket(PACKET_TYPE_KD_RESET, 0L);
|
|
return KDP_PACKET_RESEND;
|
|
}
|
|
else if (PacketHeader.PacketType == PACKET_TYPE_KD_RESEND) {
|
|
return KDP_PACKET_RESEND;
|
|
}
|
|
else {
|
|
//
|
|
// Invalid packet header, ignore it.
|
|
//
|
|
goto WaitForPacketLeader;
|
|
}
|
|
|
|
//
|
|
// The packet header is for data packet (not control packet).
|
|
//
|
|
|
|
}
|
|
else if (PacketType == PACKET_TYPE_KD_ACKNOWLEDGE) {
|
|
//
|
|
// if we are waiting for ACK packet ONLY
|
|
// and we receive a data packet header, check if the packet id
|
|
// is what we expected. If yes, assume the acknowledge is lost (but
|
|
// sent), ask sender to resend and return with PACKET_RECEIVED.
|
|
//
|
|
if (PacketHeader.PacketId == KdCompPacketIdExpected) {
|
|
KdpSendControlPacket(PACKET_TYPE_KD_RESEND, 0L);
|
|
KdCompNextPacketIdToSend ^= 1;
|
|
return KDP_PACKET_RECEIVED;
|
|
}
|
|
else {
|
|
KdpSendControlPacket(PACKET_TYPE_KD_ACKNOWLEDGE,
|
|
PacketHeader.PacketId);
|
|
goto WaitForPacketLeader;
|
|
}
|
|
}
|
|
|
|
//
|
|
// we are waiting for data packet and we received the packet header
|
|
// for data packet. Perform the following checks to make sure
|
|
// it is the packet we are waiting for.
|
|
//
|
|
|
|
//
|
|
// Check ByteCount received is valid
|
|
//
|
|
MessageLength = MessageHeader->MaximumLength;
|
|
if ((PacketHeader.ByteCount > (UINT16)PACKET_MAX_SIZE) ||
|
|
(PacketHeader.ByteCount < (UINT16)MessageLength)) {
|
|
goto SendResendPacket;
|
|
}
|
|
*DataLength = PacketHeader.ByteCount - MessageLength;
|
|
|
|
//
|
|
// Read the message header.
|
|
//
|
|
|
|
ReturnCode = KdpSerialReceiveString((PUCHAR)MessageHeader->Buffer, MessageLength);
|
|
if (ReturnCode != KDP_PACKET_RECEIVED) {
|
|
goto SendResendPacket;
|
|
}
|
|
MessageHeader->Length = (UINT16)MessageLength;
|
|
|
|
//
|
|
// Read the message data.
|
|
//
|
|
|
|
ReturnCode = KdpSerialReceiveString((PUCHAR)MessageData->Buffer, *DataLength);
|
|
if (ReturnCode != KDP_PACKET_RECEIVED) {
|
|
goto SendResendPacket;
|
|
}
|
|
MessageData->Length = (UINT16)*DataLength;
|
|
|
|
//
|
|
// Read packet trailing byte
|
|
//
|
|
|
|
ReturnCode = KdpSerialReceiveString(&Input, 1);
|
|
if (ReturnCode != KDP_PACKET_RECEIVED || Input != PACKET_TRAILING_BYTE) {
|
|
goto SendResendPacket;
|
|
}
|
|
|
|
//
|
|
// Check PacketType is what we are waiting for.
|
|
//
|
|
if (PacketType != PacketHeader.PacketType) {
|
|
KdpSendControlPacket(PACKET_TYPE_KD_ACKNOWLEDGE,
|
|
PacketHeader.PacketId);
|
|
goto WaitForPacketLeader;
|
|
}
|
|
|
|
//
|
|
// Check PacketId is valid.
|
|
//
|
|
if (PacketHeader.PacketId == INITIAL_PACKET_ID ||
|
|
PacketHeader.PacketId == (INITIAL_PACKET_ID ^ 1)) {
|
|
if (PacketHeader.PacketId != KdCompPacketIdExpected) {
|
|
KdpSendControlPacket(PACKET_TYPE_KD_ACKNOWLEDGE,
|
|
PacketHeader.PacketId);
|
|
goto WaitForPacketLeader;
|
|
}
|
|
}
|
|
else {
|
|
goto SendResendPacket;
|
|
}
|
|
|
|
//
|
|
// Check checksum is valid.
|
|
//
|
|
Checksum = KdpComputeChecksum(MessageHeader->Buffer,
|
|
MessageHeader->Length);
|
|
Checksum += KdpComputeChecksum(MessageData->Buffer,
|
|
MessageData->Length);
|
|
if (Checksum != PacketHeader.Checksum) {
|
|
goto SendResendPacket;
|
|
}
|
|
|
|
//
|
|
// Send Acknowledge byte and the Id of the packet received.
|
|
// Then, update the ExpectId for next incoming packet.
|
|
//
|
|
KdpSendControlPacket(PACKET_TYPE_KD_ACKNOWLEDGE,
|
|
PacketHeader.PacketId);
|
|
|
|
//
|
|
// We have successfully received the packet so update the
|
|
// packet control variables and return success.
|
|
//
|
|
KdCompPacketIdExpected ^= 1;
|
|
KDDBG2("KdpSerialReceivePacket - got one!\n");
|
|
return KDP_PACKET_RECEIVED;
|
|
|
|
SendResendPacket:
|
|
KdpSendControlPacket(PACKET_TYPE_KD_RESEND, 0L);
|
|
goto WaitForPacketLeader;
|
|
}
|
|
|
|
// Returns true if a breakin packet is pending.
|
|
// A packet is present if: There is a valid character which matches BREAK_CHAR.
|
|
bool KdpSerialPollBreakIn()
|
|
{
|
|
KDDBG2("KdpSerialPollBreakIn\n");
|
|
UCHAR Input;
|
|
UINT32 Status = KdpSerialReceiveString(&Input, 1, false);
|
|
KDDBG2("KdpSerialPollByte STATUS %d Input %02x\n", Status, Input);
|
|
if ((Status == KDP_PACKET_RECEIVED) && (Input == BREAKIN_PACKET_BYTE)) {
|
|
KDDBG("KDP_PACKET_RECEIVED\n");
|
|
KdDebuggerNotPresent = false;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
//
|
|
///////////////////////////////////////////////////////////////// End of File.
|