#if defined(R4000)
// TITLE("Interval and Profile Clock Interrupts")
//++
//
// Copyright (c) 1991 Microsoft Corporation
//
// Module Name:
//
// x4clock.s
//
// Abstract:
//
// This module implements the code necessary to field and process the
// interval and profile clock interrupts on a MIPS R4000 system.
//
// Author:
//
// David N. Cutler (davec) 26-Apr-1991
//
// Environment:
//
// Kernel mode only.
//
// Revision History:
//
//--
#include "halmips.h"
SBTTL("System Clock Interrupt")
//++
//
// Routine Description:
//
// This routine is entered as the result of an interrupt generated by
// the interval timer. Its function is to acknowledge the interrupt and
// transfer control to the standard system routine to update the system
// time and the execution time of the current thread and process.
//
// Arguments:
//
// s8 - Supplies a pointer to a trap frame.
//
// Return Value:
//
// None.
//
//--
.struct 0
CiArgs: .space 4 * 4 // saved arguments
.space 3 * 4 // fill
CiRa: .space 4 // saved return address
CiFrameLength: //
NESTED_ENTRY(HalpClockInterrupt, CiFrameLength, zero)
subu sp,sp,CiFrameLength // allocate stack frame
sw ra,CiRa(sp) // save return address
PROLOGUE_END
move a0,s8 // set address of trap frame
lw a1,HalpCurrentTimeIncrement // Get current time increment
jal KeUpdateSystemTime // update system time
lw t0,HalpNextTimeIncrement // Get NextTimeIncrement
sw t0,HalpCurrentTimeIncrement // Set CurrentTimeIncrement to NextTimeIncrement
lw a0,HalpNextIntervalCount // Get Next Interval Count. If 0, then no change required
beq zero,a0,5f // See if time increment is to be changed
jal HalpProgramIntervalTimer // Program timer with new interval count value
lw t0,HalpNewTimeIncrement // Get HalpNewTimeIncrement
sw t0,HalpNextTimeIncrement // Set HalpNextTimeIncrement to HalpNewTimeIncrement
sw zero,HalpNextIntervalCount // Set HalpNextIntervalCount to 0
5:
lw t0,KdDebuggerEnabled // check if debugger enabled
lbu t0,0(t0) //
beq zero,t0,10f // if eq, debugger not enabled
jal KdPollBreakIn // check if breakin is requested
beq zero,v0,10f // if eq, no breakin requested
li a0,DBG_STATUS_CONTROL_C // break in and send
jal DbgBreakPointWithStatus // status to debugger
10: lw ra,CiRa(sp) // restore return address
addu sp,sp,CiFrameLength // deallocate stack frame
j ra // return
.end HalpClockInterrupt
SBTTL("Profile Clock Interrupt")
//++
//
// Routine Description:
//
// This routine is entered as the result of an interrupt generated by the
// profile clock. Its function is to acknowledge the profile interrupt,
// compute the next compare value, update the performance counter, and
// transfer control to the standard system routine to process any active
// profiles.
//
// Arguments:
//
// s8 - Supplies a pointer to a trap frame.
//
// Return Value:
//
// None.
//
//--
LEAF_ENTRY(HalpProfileInterrupt)
.set noreorder
.set noat
mfc0 t1,count // get current count value
mfc0 t0,compare // get current comparison value
addu t1,t1,8 // factor in lost cycles
subu t1,t1,t0 // compute initial count value
mtc0 t0,compare // dismiss interrupt
mtc0 t1,count // set new count register value
.set at
.set reorder
la t1,HalpPerformanceCounter // get performance counter address
lw t2,LiLowPart(t1) // get low part of performance count
lw t3,LiHighPart(t1) // get high part of performance count
addu t2,t2,t0 // update low part of performance count
sw t2,LiLowPart(t1) // store low part of performance count
sltu t4,t2,t0 // generate carry into high part
addu t3,t3,t4 // update high part of performance count
sw t3,LiHighPart(t1) // store high part of performance count
move a0,s8 // set address of trap frame
j KeProfileInterrupt // process profile entries
.end HalpProfileInterrupt
SBTTL("Read Count Register")
//++
//
// ULONG
// HalpReadCountRegister (
// VOID
// );
//
// Routine Description:
//
// This routine reads the current value of the count register and
// returns the value.
//
// Arguments:
//
// None.
//
// Return Value:
//
// Current value of the count register.
//
//--
LEAF_ENTRY(HalpReadCountRegister)
.set noreorder
.set noat
mfc0 v0,count // get count register value
.set at
.set reorder
j ra // return
.end HalpReadCountRegister
SBTTL("Write Compare Register And Clear")
//++
//
// ULONG
// HalpWriteCompareRegisterAndClear (
// IN ULONG Value
// );
//
// Routine Description:
//
// This routine reads the current value of the count register, writes
// the value of the compare register, clears the count register, and
// returns the previous value of the count register.
//
// Arguments:
//
// Value - Supplies the value written to the compare register.
//
// Return Value:
//
// Previous value of the count register.
//
//--
LEAF_ENTRY(HalpWriteCompareRegisterAndClear)
.set noreorder
.set noat
mfc0 v0,count // get count register value
mtc0 a0,compare // set compare register value
li t0,7 // set lost cycle count
mtc0 t0,count // set count register to zero
.set at
.set reorder
j ra // return
.end HalpWriteCompareRegisterAndClear
#endif
