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750 lines
20 KiB
750 lines
20 KiB
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title "Interval Clock Interrupt"
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;++
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;
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; Copyright (c) 1989 Microsoft Corporation
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;
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; Module Name:
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;
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; ixclock.asm
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;
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; Abstract:
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;
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; This module implements the code necessary to field and process the
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; interval clock interrupt.
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;
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; Author:
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;
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; Shie-Lin Tzong (shielint) 12-Jan-1990
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;
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; Environment:
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;
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; Kernel mode only.
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;
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; Revision History:
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;
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; bryanwi 20-Sep-90
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;
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; Add KiSetProfileInterval, KiStartProfileInterrupt,
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; KiStopProfileInterrupt procedures.
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; KiProfileInterrupt ISR.
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; KiProfileList, KiProfileLock are delcared here.
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;
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; shielint 10-Dec-90
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; Add performance counter support.
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; Move system clock to irq8, ie we now use RTC to generate system
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; clock. Performance count and Profile use timer 1 counter 0.
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; The interval of the irq0 interrupt can be changed by
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; KiSetProfileInterval. Performance counter does not care about the
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; interval of the interrupt as long as it knows the rollover count.
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; Note: Currently I implemented 1 performance counter for the whole
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; i386 NT.
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;
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; John Vert (jvert) 11-Jul-1991
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; Moved from ke\i386 to hal\i386. Removed non-HAL stuff
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;
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; shie-lin tzong (shielint) 13-March-92
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; Move System clock back to irq0 and use RTC (irq8) to generate
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; profile interrupt. Performance counter and system clock use time1
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; counter 0 of 8254.
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;
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; Landy Wang (corollary!landy) 04-Dec-92
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; Move much code into separate modules for easy inclusion by various
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; HAL builds.
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;
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;--
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.386p
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.xlist
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include hal386.inc
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include callconv.inc ; calling convention macros
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include i386\ix8259.inc
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include i386\kimacro.inc
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include mac386.inc
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include i386\ixcmos.inc
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.list
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EXTRNP _KeUpdateSystemTime,0
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EXTRNP Kei386EoiHelper,0,IMPORT
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EXTRNP _KeSetTimeIncrement,2,IMPORT
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EXTRNP _HalEndSystemInterrupt,2
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EXTRNP _HalBeginSystemInterrupt,3
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EXTRNP _HalpReleaseCmosSpinLock ,0
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EXTRNP _HalpMcaQueueDpc, 0
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EXTRNP _HalpBrokenPiix4TimerTick, 0
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extrn _HalpBrokenAcpiTimer:byte
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extrn _QueryTimer:DWORD
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extrn _KdEnteredDebugger:DWORD
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extrn _HalpTimerWatchdogEnabled:DWORD
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extrn _HalpTimerWatchdogStorage:DWORD
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extrn _HalpTimerWatchdogCurFrame:DWORD
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extrn _HalpTimerWatchdogLastFrame:DWORD
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extrn _HalpTimerWatchdogStorageOverflow:DWORD
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;
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; Constants used to initialize timer 0
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;
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TIMER1_DATA_PORT0 EQU 40H ; Timer1, channel 0 data port
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TIMER1_CONTROL_PORT0 EQU 43H ; Timer1, channel 0 control port
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TIMER2_DATA_PORT0 EQU 48H ; Timer1, channel 0 data port
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TIMER2_CONTROL_PORT0 EQU 4BH ; Timer1, channel 0 control port
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TIMER1_IRQ EQU 0 ; Irq 0 for timer1 interrupt
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COMMAND_8254_COUNTER0 EQU 00H ; Select count 0
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COMMAND_8254_RW_16BIT EQU 30H ; Read/Write LSB firt then MSB
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COMMAND_8254_MODE2 EQU 4 ; Use mode 2
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COMMAND_8254_BCD EQU 0 ; Binary count down
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COMMAND_8254_LATCH_READ EQU 0 ; Latch read command
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PERFORMANCE_FREQUENCY EQU 1193182
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COUNTER_TICKS_AVG_SHIFT EQU 4
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COUNTER_TICKS_FOR_AVG EQU 16
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PAGE_SIZE EQU 1000H
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FRAME_COPY_SIZE EQU 64
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;
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; ==== Values used for System Clock ====
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;
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_DATA SEGMENT DWORD PUBLIC 'DATA'
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;
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; The following array stores the per microsecond loop count for each
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; central processor.
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;
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;
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; 8254 performance counter.
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;
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public HalpCurrentRollOver, HalpCurrentTimeIncrement, _HalpCurrentMSRateTableIndex
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HalpCurrentRollOver dd 0
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HalpCurrentTimeIncrement dd 0
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_HalpCurrentMSRateTableIndex dd 0
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public _HalpClockWork, _HalpClockSetMSRate, _HalpClockMcaQueueDpc
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_HalpClockWork label dword
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_HalpClockSetMSRate db 0
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_HalpClockMcaQueueDpc db 0
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_bReserved1 db 0
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_bReserved2 db 0
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;
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; timer latency watchdog variables
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;
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public _HalpWatchdogAvgCounter, _HalpWatchdogCountLow, _HalpWatchdogCountHigh
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public _HalpWatchdogTscLow, _HalpWatchdogTscHigh
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_HalpWatchdogAvgCounter dd 0
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_HalpWatchdogCountLow dd 0
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_HalpWatchdogCountHigh dd 0
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_HalpWatchdogTscLow dd 0
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_HalpWatchdogTscHigh dd 0
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_DATA ends
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_TEXT SEGMENT DWORD PUBLIC 'DATA'
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;
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; Convert the interval to rollover count for 8254 Timer1 device.
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; Timer1 counts down a 16 bit value at a rate of 1.193181667M counts-per-sec.
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; (The main crystal freq is 14.31818, and this is a divide by 12)
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;
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; The best fit value closest to 10ms is 10.0144012689ms:
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; ROLLOVER_COUNT 11949
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; TIME_INCREMENT 100144
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; Calculated error is -.0109472 s/day
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;
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;
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; The following table contains 8254 values timer values to use at
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; any given ms setting from 1ms - 15ms. All values work out to the
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; same error per day (-.0109472 s/day).
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;
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public HalpRollOverTable
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; RollOver Time
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; Count Increment MS
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HalpRollOverTable dd 1197, 10032 ; 1 ms
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dd 2394, 20064 ; 2 ms
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dd 3591, 30096 ; 3 ms
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dd 4767, 39952 ; 4 ms
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dd 5964, 49984 ; 5 ms
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dd 7161, 60016 ; 6 ms
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dd 8358, 70048 ; 7 ms
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dd 9555, 80080 ; 8 ms
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dd 10731, 89936 ; 9 ms
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dd 11949, 100144 ; 10 ms
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dd 13125, 110000 ; 11 ms
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dd 14322, 120032 ; 12 ms
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dd 15519, 130064 ; 13 ms
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dd 16695, 139920 ; 14 ms
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dd 17892, 149952 ; 15 ms
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TimeIncr equ 4
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RollOver equ 0
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_TEXT ends
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_DATA SEGMENT DWORD PUBLIC 'DATA'
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public HalpLargestClockMS, _HalpNextMSRate, HalpPendingMSRate
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HalpLargestClockMS dd 15 ; Table goes to 15MS
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_HalpNextMSRate dd 14
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HalpPendingMSRate dd 0
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extrn _TimerInfo:DWORD
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BiasLow equ 20
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BiasHigh equ 24
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_DATA ends
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PAGELK SEGMENT DWORD PUBLIC 'CODE'
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ASSUME DS:FLAT, ES:FLAT, SS:NOTHING, FS:NOTHING, GS:NOTHING
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page ,132
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subttl "Initialize Clock"
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;++
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;
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; VOID
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; HalpInitializeClock (
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; )
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;
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; Routine Description:
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;
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; This routine initialize system time clock using 8254 timer1 counter 0
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; to generate an interrupt at every 15ms interval at 8259 irq0.
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;
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; See the definitions of TIME_INCREMENT and ROLLOVER_COUNT if clock rate
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; needs to be changed.
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;
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; Arguments:
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;
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; None
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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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cPublicProc _HalpInitializeClock ,0
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mov eax, PCR[PcPrcb]
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cmp byte ptr [eax].PbCpuType, 4 ; 486 or better?
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jc short @f ; no, skip
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mov HalpLargestClockMS, 10 ; Limit 486's to 10MS
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mov _HalpNextMSRate, 9
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@@:
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mov eax, HalpLargestClockMS
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mov _HalpCurrentMSRateTableIndex, eax
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dec _HalpCurrentMSRateTableIndex
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mov ecx, HalpRollOverTable.TimeIncr
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mov edx, HalpRollOverTable[eax*8-8].TimeIncr
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mov eax, HalpRollOverTable[eax*8-8].RollOver
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mov HalpCurrentTimeIncrement, edx
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;
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; (ecx) = Min time_incr
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; (edx) = Max time_incr
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; (eax) = max roll over count
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;
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push eax
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stdCall _KeSetTimeIncrement, <edx, ecx>
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pop ecx
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;
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; timer latency watchdog initialization
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;
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cmp _HalpTimerWatchdogEnabled, 0
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jz short @f
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.586p
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rdtsc
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.386p
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mov _HalpWatchdogAvgCounter, COUNTER_TICKS_FOR_AVG
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mov _HalpWatchdogTscLow, eax
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mov _HalpWatchdogTscHigh, edx
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xor eax, eax
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mov _HalpWatchdogCountLow, eax
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mov _HalpWatchdogCountHigh, eax
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@@:
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pushfd ; save caller's eflag
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cli ; make sure interrupts are disabled
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;
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; Set clock rate
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; (ecx) = RollOverCount
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;
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mov al,COMMAND_8254_COUNTER0+COMMAND_8254_RW_16BIT+COMMAND_8254_MODE2
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out TIMER1_CONTROL_PORT0, al ;program count mode of timer 0
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IoDelay
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mov al, cl
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out TIMER1_DATA_PORT0, al ; program timer 0 LSB count
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IoDelay
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mov al,ch
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out TIMER1_DATA_PORT0, al ; program timer 0 MSB count
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popfd ; restore caller's eflag
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mov HalpCurrentRollOver, ecx ; Set RollOverCount & initialized
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stdRET _HalpInitializeClock
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stdENDP _HalpInitializeClock
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PAGELK ends
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_TEXT$03 SEGMENT DWORD PUBLIC 'CODE'
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ASSUME DS:FLAT, ES:FLAT, SS:NOTHING, FS:NOTHING, GS:NOTHING
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page ,132
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subttl "System Clock Interrupt"
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;++
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;
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; Routine Description:
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;
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; This routine is entered as the result of an interrupt generated by CLOCK.
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; Its function is to dismiss the interrupt, raise system Irql to
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; CLOCK2_LEVEL, update performance counter and transfer control to the
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; standard system routine to update the system time and the execution
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; time of the current thread
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; and process.
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;
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; Arguments:
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;
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; None
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; Interrupt is disabled
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;
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; Return Value:
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;
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; Does not return, jumps directly to KeUpdateSystemTime, which returns
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;
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; Sets Irql = CLOCK2_LEVEL and dismisses the interrupt
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;
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;--
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ENTER_DR_ASSIST Hci_a, Hci_t
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cPublicProc _HalpClockInterrupt ,0
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;
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; Save machine state in trap frame
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;
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ENTER_INTERRUPT Hci_a, Hci_t
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;
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; (esp) - base of trap frame
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;
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ifdef MCA
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;
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; Special hack for MCA machines
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;
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in al, 61h
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jmp $+2
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or al, 80h
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out 61h, al
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jmp $+2
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endif ; MCA
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;
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; Dismiss interrupt and raise irq level to clock2 level
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;
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Hci10:
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push CLOCK_VECTOR
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sub esp, 4 ; allocate space to save OldIrql
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stdCall _HalBeginSystemInterrupt, <CLOCK2_LEVEL, CLOCK_VECTOR, esp>
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or al,al ; check for spurious interrupt
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jz Hci100
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;
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; Check to see if we need to fix up a broken PIIX4
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;
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.if (_HalpBrokenAcpiTimer)
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stdCall _HalpBrokenPiix4TimerTick
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.endif
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;
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; Timer latency watchdog
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;
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cmp _HalpTimerWatchdogEnabled, 0
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jz Hci14
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.586p
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rdtsc
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.386p
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;
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; Compare difference to watchdog count, while storing a copy of the
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; current counter.
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;
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xor ebx, ebx
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push eax
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push edx
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sub eax, _HalpWatchdogTscLow
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sbb edx, _HalpWatchdogTscHigh
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pop _HalpWatchdogTscHigh
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pop _HalpWatchdogTscLow
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js Hci115 ; Was this a bogus counter?
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; (e.g, negative delta)
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push eax
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mov ecx, dword ptr _KdEnteredDebugger
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xor eax, eax
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xchg eax, [ecx]
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or al, al
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pop eax
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jnz Hci14
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cmp HalpPendingMSRate, ebx ; Was a new rate set during last
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jnz Hci14 ; tick? Yes, skip this compare
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;
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; If we need to compute the average of the time-stamp counter for
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; the current period, add the delta to the counter.
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;
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cmp _HalpWatchdogAvgCounter, ebx
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jnz Hci12
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cmp edx, _HalpWatchdogCountHigh
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ja short Hci11
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jb Hci14
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cmp eax, _HalpWatchdogCountLow
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jbe Hci14
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Hci11:
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cmp dword ptr [_HalpTimerWatchdogStorageOverflow], 0
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jne short Hci115
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;
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; copy FRAME_COPY_SIZE dwords from the stack, or to next page boundary,
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; whichever is less
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;
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push esi
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push edi
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lea esi, [esp + 8]
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lea ecx, [esi + PAGE_SIZE - 1]
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and ecx, NOT(PAGE_SIZE - 1)
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sub ecx, esi
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shr ecx, 2
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cmp ecx, FRAME_COPY_SIZE
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jbe short Hci111
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mov ecx, FRAME_COPY_SIZE
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Hci111:
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mov edi, dword ptr _HalpTimerWatchdogCurFrame
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rep movsd
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add dword ptr _HalpTimerWatchdogCurFrame, (FRAME_COPY_SIZE*4)
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;
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; If we didn't copy an entire FRAME_COPY_SIZE dwords, zero fill.
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;
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mov ecx, dword ptr _HalpTimerWatchdogCurFrame
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sub ecx, edi
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shr ecx, 2
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xor eax, eax
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rep stosd
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cmp edi, dword ptr _HalpTimerWatchdogLastFrame
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jbe short Hci112
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mov dword ptr [_HalpTimerWatchdogStorageOverflow], 1
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Hci112:
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pop edi
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pop esi
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Hci115:
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;
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; reset last time so that we're accurate after the trap
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;
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.586p
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rdtsc
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.386p
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mov _HalpWatchdogTscHigh, edx
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mov _HalpWatchdogTscLow, eax
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jmp short Hci14
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Hci12:
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;
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; Increment the total counter, perform average when the count is reached
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;
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add _HalpWatchdogCountLow, eax
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adc _HalpWatchdogCountHigh, edx
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dec _HalpWatchdogAvgCounter
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jnz short Hci14
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mov edx, _HalpWatchdogCountHigh
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mov eax, _HalpWatchdogCountLow
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;
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; compute the average * 2, this measures when we have missed
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; an interrupt at this rate.
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;
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mov ecx, COUNTER_TICKS_AVG_SHIFT - 1
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Hci13:
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shr edx, 1
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rcr eax, 1
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loop short Hci13
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mov _HalpWatchdogCountLow, eax
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mov _HalpWatchdogCountHigh, edx
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Hci14:
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;
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; Check for any more work
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;
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mov eax, HalpCurrentTimeIncrement
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xor ebx, ebx
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cmp _HalpClockWork, ebx ; Any clock interrupt work desired?
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jz _KeUpdateSystemTime@0 ; No, process tick
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cmp _HalpClockMcaQueueDpc, bl
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je short Hci20
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mov _HalpClockMcaQueueDpc, bl
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;
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; Queue MCA Dpc
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;
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push eax
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stdCall _HalpMcaQueueDpc ; Queue MCA Dpc
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pop eax
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Hci20:
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;
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; (esp) = OldIrql
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; (esp+4) = Vector
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; (esp+8) = base of trap frame
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; ebp = trap frame
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; eax = time increment
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; ebx = 0
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;
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cmp _HalpClockSetMSRate, bl ; New clock rate desired?
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jz _KeUpdateSystemTime@0 ; No, process tick
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;
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; Time of clock frequency is being changed. See if the 8254 was
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; was reprogrammed for a new rate during last tick
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;
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cmp HalpPendingMSRate, ebx ; Was a new rate set durning last
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jnz short Hci50 ; tick? Yes, go update globals
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Hci40:
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; (eax) = time increment for current tick
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;
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; A new clock rate needs to be set. Setting the rate here will
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; cause the tick after the next tick to be at the new rate.
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; (the next tick is already in progress by the 8254 and will occur
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; at the same rate as this tick)
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;
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mov ebx, _HalpNextMSRate
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mov HalpPendingMSRate, ebx ; pending rate
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|
|
mov ecx, HalpRollOverTable[ebx*8-8].RollOver
|
|
|
|
;
|
|
; Set clock rate
|
|
; (ecx) = RollOverCount
|
|
;
|
|
push eax ; save current tick's rate
|
|
|
|
mov al,COMMAND_8254_COUNTER0+COMMAND_8254_RW_16BIT+COMMAND_8254_MODE2
|
|
out TIMER1_CONTROL_PORT0, al ;program count mode of timer 0
|
|
IoDelay
|
|
mov al, cl
|
|
out TIMER1_DATA_PORT0, al ; program timer 0 LSB count
|
|
IoDelay
|
|
mov al,ch
|
|
out TIMER1_DATA_PORT0, al ; program timer 0 MSB count
|
|
|
|
pop eax
|
|
|
|
;
|
|
; (esp) = OldIrql
|
|
; (esp+4) = Vector
|
|
; (esp+8) = base of trap frame
|
|
; ebp = trap frame
|
|
; eax = time increment
|
|
;
|
|
jmp _KeUpdateSystemTime@0 ; dispatch this tick
|
|
|
|
Hci50:
|
|
;
|
|
; The next tick will occur at the rate which was programmed during the last
|
|
; tick. Update globals for new rate which starts with the next tick.
|
|
;
|
|
; (eax) = time increment for current tick
|
|
;
|
|
mov ebx, HalpPendingMSRate
|
|
mov _HalpCurrentMSRateTableIndex, ebx
|
|
dec _HalpCurrentMSRateTableIndex
|
|
mov ecx, HalpRollOverTable[ebx*8-8].RollOver
|
|
mov edx, HalpRollOverTable[ebx*8-8].TimeIncr
|
|
|
|
mov HalpCurrentRollOver, ecx
|
|
mov HalpCurrentTimeIncrement, edx ; next tick rate
|
|
mov HalpPendingMSRate, 0 ; no longer pending, clear it
|
|
|
|
cmp _HalpTimerWatchdogEnabled, 0
|
|
jz short @f
|
|
|
|
;
|
|
; Schedule to recalibrate watchdog counter
|
|
;
|
|
push eax
|
|
.586p
|
|
rdtsc
|
|
.386p
|
|
mov _HalpWatchdogAvgCounter, COUNTER_TICKS_FOR_AVG
|
|
mov _HalpWatchdogTscLow, eax
|
|
mov _HalpWatchdogTscHigh, edx
|
|
|
|
xor eax,eax
|
|
mov _HalpWatchdogCountHigh, eax
|
|
mov _HalpWatchdogCountLow, eax
|
|
pop eax
|
|
@@:
|
|
|
|
cmp ebx, _HalpNextMSRate ; new rate == NextRate?
|
|
jne Hci40 ; no, go set new pending rate
|
|
|
|
mov _HalpClockSetMSRate, 0 ; all done setting new rate
|
|
jmp _KeUpdateSystemTime@0 ; dispatch this tick
|
|
|
|
Hci100:
|
|
add esp, 8 ; spurious, no EndOfInterrupt
|
|
SPURIOUS_INTERRUPT_EXIT ; exit interrupt without eoi
|
|
|
|
stdENDP _HalpClockInterrupt
|
|
|
|
;++
|
|
;
|
|
; ULONG
|
|
; HalpAcpiTimerSetTimeIncrement (
|
|
; IN ULONG DesiredIncrement
|
|
; )
|
|
;
|
|
; /*++
|
|
;
|
|
; Routine Description:
|
|
;
|
|
; This routine initialize system time clock to generate an
|
|
; interrupt at every DesiredIncrement interval.
|
|
;
|
|
; Arguments:
|
|
;
|
|
; DesiredIncrement - desired interval between every timer tick (in
|
|
; 100ns unit.)
|
|
;
|
|
; Return Value:
|
|
;
|
|
; The *REAL* time increment set.
|
|
;--
|
|
cPublicProc _HalpAcpiTimerSetTimeIncrement,1
|
|
|
|
mov eax, [esp+4] ; desired setting
|
|
xor edx, edx
|
|
mov ecx, 9990
|
|
div ecx ; round to MS
|
|
|
|
cmp eax, HalpLargestClockMS ; MS > max?
|
|
jc short @f
|
|
mov eax, HalpLargestClockMS ; yes, use max
|
|
@@:
|
|
or eax, eax ; MS < min?
|
|
jnz short @f
|
|
inc eax ; yes, use min
|
|
@@:
|
|
mov _HalpNextMSRate, eax
|
|
mov _HalpClockSetMSRate, 1 ; New clock rate desired.
|
|
|
|
mov eax, HalpRollOverTable[eax*8-8].TimeIncr
|
|
stdRET _HalpAcpiTimerSetTimeIncrement
|
|
|
|
stdENDP _HalpAcpiTimerSetTimeIncrement
|
|
|
|
page ,132
|
|
subttl "Query 8254 Counter"
|
|
;++
|
|
;
|
|
; ULONG
|
|
; HalpQuery8254Counter(
|
|
; VOID
|
|
; )
|
|
;
|
|
; Routine Description:
|
|
;
|
|
; This routine returns the current value of the 8254 counter
|
|
;
|
|
; Arguments:
|
|
;
|
|
; None
|
|
;
|
|
; Return Value:
|
|
;
|
|
; Current value of the 8254 counter is returned
|
|
;
|
|
;--
|
|
|
|
cPublicProc _HalpQuery8254Counter, 0
|
|
|
|
pushfd
|
|
cli
|
|
|
|
;
|
|
; Fetch the current counter value from the hardware
|
|
;
|
|
|
|
mov al, COMMAND_8254_LATCH_READ + COMMAND_8254_COUNTER0
|
|
; Latch PIT Ctr 0 command.
|
|
out TIMER1_CONTROL_PORT0, al
|
|
IODelay
|
|
in al, TIMER1_DATA_PORT0 ; Read PIT Ctr 0, LSByte.
|
|
IODelay
|
|
movzx ecx, al ; Zero upper bytes of (ECX).
|
|
in al, TIMER1_DATA_PORT0 ; Read PIT Ctr 0, MSByte.
|
|
mov ch, al ; (CX) = PIT Ctr 0 count.
|
|
|
|
mov eax, ecx
|
|
|
|
popfd ; restore interrupt flag
|
|
|
|
stdRET _HalpQuery8254Counter
|
|
|
|
stdENDP _HalpQuery8254Counter
|
|
|
|
_TEXT$03 ends
|
|
|
|
end
|