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Changed TODOs to TBDs

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date	2001.04.26.18.14.00;	author psdiefen;	state Exp;
This commit is contained in:
aystarik 2005-06-29 16:58:26 +00:00
parent f674bdc7d3
commit cc934c8964
1 changed files with 19 additions and 19 deletions
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38
source/components/hardware/hwtimer.c
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@ -2,7 +2,7 @@
/******************************************************************************
*
* Name: hwtimer.c - ACPI Power Management Timer Interface
* $Revision: 1.5 $
* $Revision: 1.8 $
*
*****************************************************************************/
@ -118,7 +118,7 @@
#include "acpi.h"
#include "achware.h"
#define _COMPONENT HARDWARE
#define _COMPONENT ACPI_HARDWARE
MODULE_NAME ("hwtimer")
@ -195,20 +195,20 @@ AcpiGetTimer (
* EndTicks
* TimeElapsed
*
* RETURN: TimeElapsed
* RETURN: TimeElapsed
*
* DESCRIPTION: Computes the time elapsed (in microseconds) between two
* PM Timer time stamps, taking into account the possibility of
* rollovers, the timer resolution, and timer frequency.
*
* The PM Timer's clock ticks at roughly 3.6 times per
* rollovers, the timer resolution, and timer frequency.
*
* The PM Timer's clock ticks at roughly 3.6 times per
* _microsecond_, and its clock continues through Cx state
* transitions (unlike many CPU timestamp counters) -- making it
* a versatile and accurate timer.
*
* Note that this function accomodates only a single timer
* Note that this function accomodates only a single timer
* rollover. Thus for 24-bit timers, this function should only
* be used for calculating durations less than ~4.6 seconds
* be used for calculating durations less than ~4.6 seconds
* (~20 hours for 32-bit timers).
*
******************************************************************************/
@ -227,12 +227,12 @@ AcpiGetTimerDuration (
FUNCTION_TRACE ("AcpiGetTimerDuration");
if (!TimeElapsed)
if (!TimeElapsed)
{
return_ACPI_STATUS (AE_BAD_PARAMETER);
}
/*
/*
* Compute Tick Delta:
* -------------------
* Handle (max one) timer rollovers on 24- versus 32-bit timers.
@ -241,7 +241,7 @@ AcpiGetTimerDuration (
{
DeltaTicks = EndTicks - StartTicks;
}
else if (StartTicks > EndTicks)
else if (StartTicks > EndTicks)
{
/* 24-bit Timer */
if (0 == AcpiGbl_FADT->TmrValExt)
@ -249,7 +249,7 @@ AcpiGetTimerDuration (
DeltaTicks = (((0x00FFFFFF - StartTicks) + EndTicks) & 0x00FFFFFF);
}
/* 32-bit Timer */
else
else
{
DeltaTicks = (0xFFFFFFFF - StartTicks) + EndTicks;
}
@ -260,17 +260,17 @@ AcpiGetTimerDuration (
return_ACPI_STATUS (AE_OK);
}
/*
/*
* Compute Duration:
* -----------------
* Since certain compilers (gcc/Linux, argh!) don't support 64-bit
* divides in kernel-space we have to do some trickery to preserve
* Since certain compilers (gcc/Linux, argh!) don't support 64-bit
* divides in kernel-space we have to do some trickery to preserve
* accuracy while using 32-bit math.
*
* TODO: Change to use 64-bit math when supported.
*
* TBD: Change to use 64-bit math when supported.
*
* The process is as follows:
* 1. Compute the number of seconds by dividing Delta Ticks by
* 1. Compute the number of seconds by dividing Delta Ticks by
* the timer frequency.
* 2. Compute the number of milliseconds in the remainder from step #1
* by multiplying by 1000 and then dividing by the timer frequency.
@ -278,7 +278,7 @@ AcpiGetTimerDuration (
* by multiplying by 1000 and then dividing by the timer frequency.
* 4. Add the results from steps 1, 2, and 3 to get the total duration.
*
* Example: The time elapsed for DeltaTicks = 0xFFFFFFFF should be
* Example: The time elapsed for DeltaTicks = 0xFFFFFFFF should be
* 1199864031 microseconds. This is computed as follows:
* Step #1: Seconds = 1199; Remainder = 3092840
* Step #2: Milliseconds = 864; Remainder = 113120