diff options
Diffstat (limited to 'sys/contrib/dev/acpica/hwtimer.c')
| -rw-r--r-- | sys/contrib/dev/acpica/hwtimer.c | 76 |
1 files changed, 20 insertions, 56 deletions
diff --git a/sys/contrib/dev/acpica/hwtimer.c b/sys/contrib/dev/acpica/hwtimer.c index 4a031176e6ee..8339b2787022 100644 --- a/sys/contrib/dev/acpica/hwtimer.c +++ b/sys/contrib/dev/acpica/hwtimer.c @@ -2,7 +2,7 @@ /****************************************************************************** * * Name: hwtimer.c - ACPI Power Management Timer Interface - * $Revision: 14 $ + * $Revision: 19 $ * *****************************************************************************/ @@ -10,7 +10,7 @@ * * 1. Copyright Notice * - * Some or all of this work - Copyright (c) 1999, 2000, 2001, Intel Corp. + * Some or all of this work - Copyright (c) 1999 - 2002, Intel Corp. * All rights reserved. * * 2. License @@ -119,7 +119,7 @@ #include "achware.h" #define _COMPONENT ACPI_HARDWARE - MODULE_NAME ("hwtimer") + ACPI_MODULE_NAME ("hwtimer") /****************************************************************************** @@ -138,7 +138,7 @@ ACPI_STATUS AcpiGetTimerResolution ( UINT32 *Resolution) { - FUNCTION_TRACE ("AcpiGetTimerResolution"); + ACPI_FUNCTION_TRACE ("AcpiGetTimerResolution"); if (!Resolution) @@ -150,7 +150,6 @@ AcpiGetTimerResolution ( { *Resolution = 24; } - else { *Resolution = 32; @@ -176,7 +175,7 @@ ACPI_STATUS AcpiGetTimer ( UINT32 *Ticks) { - FUNCTION_TRACE ("AcpiGetTimer"); + ACPI_FUNCTION_TRACE ("AcpiGetTimer"); if (!Ticks) @@ -224,13 +223,12 @@ AcpiGetTimerDuration ( UINT32 *TimeElapsed) { UINT32 DeltaTicks = 0; - UINT32 Seconds = 0; - UINT32 Milliseconds = 0; - UINT32 Microseconds = 0; - UINT32 Remainder = 0; + UINT64_OVERLAY NormalizedTicks; + ACPI_STATUS Status; + ACPI_INTEGER OutQuotient; - FUNCTION_TRACE ("AcpiGetTimerDuration"); + ACPI_FUNCTION_TRACE ("AcpiGetTimerDuration"); if (!TimeElapsed) @@ -247,24 +245,21 @@ AcpiGetTimerDuration ( { DeltaTicks = EndTicks - StartTicks; } - else if (StartTicks > EndTicks) { - /* 24-bit Timer */ - if (0 == AcpiGbl_FADT->TmrValExt) { + /* 24-bit Timer */ + DeltaTicks = (((0x00FFFFFF - StartTicks) + EndTicks) & 0x00FFFFFF); } - - /* 32-bit Timer */ - else { + /* 32-bit Timer */ + DeltaTicks = (0xFFFFFFFF - StartTicks) + EndTicks; } } - else { *TimeElapsed = 0; @@ -274,49 +269,18 @@ AcpiGetTimerDuration ( /* * 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 - * accuracy while using 32-bit math. - * - * 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 - * 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. - * 3. Compute the number of microseconds in the remainder from step #2 - * 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. + * Requires a 64-bit divide: * - * 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 - * Step #3: Microseconds = 31; Remainder = <don't care!> + * TimeElapsed = (DeltaTicks * 1000000) / PM_TIMER_FREQUENCY; */ + NormalizedTicks.Full = ((UINT64) DeltaTicks) * 1000000; - /* Step #1 */ + Status = AcpiUtShortDivide (&NormalizedTicks.Full, PM_TIMER_FREQUENCY, + &OutQuotient, NULL); - Seconds = DeltaTicks / PM_TIMER_FREQUENCY; - Remainder = DeltaTicks % PM_TIMER_FREQUENCY; - - /* Step #2 */ - - Milliseconds = (Remainder * 1000) / PM_TIMER_FREQUENCY; - Remainder = (Remainder * 1000) % PM_TIMER_FREQUENCY; - - /* Step #3 */ - - Microseconds = (Remainder * 1000) / PM_TIMER_FREQUENCY; - - /* Step #4 */ - - *TimeElapsed = Seconds * 1000000; - *TimeElapsed += Milliseconds * 1000; - *TimeElapsed += Microseconds; - - return_ACPI_STATUS (AE_OK); + *TimeElapsed = (UINT32) OutQuotient; + return_ACPI_STATUS (Status); } |