summaryrefslogtreecommitdiff
path: root/drivers/acpi/acpica/hwtimer.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/acpi/acpica/hwtimer.c')
-rw-r--r--drivers/acpi/acpica/hwtimer.c93
1 files changed, 39 insertions, 54 deletions
diff --git a/drivers/acpi/acpica/hwtimer.c b/drivers/acpi/acpica/hwtimer.c
index 0c1a8bbd05d6..a5e0bccae6a4 100644
--- a/drivers/acpi/acpica/hwtimer.c
+++ b/drivers/acpi/acpica/hwtimer.c
@@ -1,47 +1,14 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Name: hwtimer.c - ACPI Power Management Timer Interface
*
+ * Copyright (C) 2000 - 2025, Intel Corp.
+ *
*****************************************************************************/
-/*
- * Copyright (C) 2000 - 2013, Intel Corp.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions, and the following disclaimer,
- * without modification.
- * 2. Redistributions in binary form must reproduce at minimum a disclaimer
- * substantially similar to the "NO WARRANTY" disclaimer below
- * ("Disclaimer") and any redistribution must be conditioned upon
- * including a substantially similar Disclaimer requirement for further
- * binary redistribution.
- * 3. Neither the names of the above-listed copyright holders nor the names
- * of any contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * Alternatively, this software may be distributed under the terms of the
- * GNU General Public License ("GPL") version 2 as published by the Free
- * Software Foundation.
- *
- * NO WARRANTY
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
- * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGES.
- */
-
-#include <linux/export.h>
+#define EXPORT_ACPI_INTERFACES
+
#include <acpi/acpi.h>
#include "accommon.h"
@@ -93,6 +60,7 @@ ACPI_EXPORT_SYMBOL(acpi_get_timer_resolution)
acpi_status acpi_get_timer(u32 * ticks)
{
acpi_status status;
+ u64 timer_value;
ACPI_FUNCTION_TRACE(acpi_get_timer);
@@ -100,7 +68,19 @@ acpi_status acpi_get_timer(u32 * ticks)
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
- status = acpi_hw_read(ticks, &acpi_gbl_FADT.xpm_timer_block);
+ /* ACPI 5.0A: PM Timer is optional */
+
+ if (!acpi_gbl_FADT.xpm_timer_block.address) {
+ return_ACPI_STATUS(AE_SUPPORT);
+ }
+
+ status = acpi_hw_read(&timer_value, &acpi_gbl_FADT.xpm_timer_block);
+ if (ACPI_SUCCESS(status)) {
+
+ /* ACPI PM Timer is defined to be 32 bits (PM_TMR_LEN) */
+
+ *ticks = (u32)timer_value;
+ }
return_ACPI_STATUS(status);
}
@@ -136,10 +116,10 @@ ACPI_EXPORT_SYMBOL(acpi_get_timer)
*
******************************************************************************/
acpi_status
-acpi_get_timer_duration(u32 start_ticks, u32 end_ticks, u32 * time_elapsed)
+acpi_get_timer_duration(u32 start_ticks, u32 end_ticks, u32 *time_elapsed)
{
acpi_status status;
- u32 delta_ticks;
+ u64 delta_ticks;
u64 quotient;
ACPI_FUNCTION_TRACE(acpi_get_timer_duration);
@@ -148,30 +128,35 @@ acpi_get_timer_duration(u32 start_ticks, u32 end_ticks, u32 * time_elapsed)
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
+ /* ACPI 5.0A: PM Timer is optional */
+
+ if (!acpi_gbl_FADT.xpm_timer_block.address) {
+ return_ACPI_STATUS(AE_SUPPORT);
+ }
+
+ if (start_ticks == end_ticks) {
+ *time_elapsed = 0;
+ return_ACPI_STATUS(AE_OK);
+ }
+
/*
* Compute Tick Delta:
* Handle (max one) timer rollovers on 24-bit versus 32-bit timers.
*/
- if (start_ticks < end_ticks) {
- delta_ticks = end_ticks - start_ticks;
- } else if (start_ticks > end_ticks) {
+ delta_ticks = end_ticks;
+ if (start_ticks > end_ticks) {
if ((acpi_gbl_FADT.flags & ACPI_FADT_32BIT_TIMER) == 0) {
/* 24-bit Timer */
- delta_ticks =
- (((0x00FFFFFF - start_ticks) +
- end_ticks) & 0x00FFFFFF);
+ delta_ticks |= (u64)1 << 24;
} else {
/* 32-bit Timer */
- delta_ticks = (0xFFFFFFFF - start_ticks) + end_ticks;
+ delta_ticks |= (u64)1 << 32;
}
- } else { /* start_ticks == end_ticks */
-
- *time_elapsed = 0;
- return_ACPI_STATUS(AE_OK);
}
+ delta_ticks -= start_ticks;
/*
* Compute Duration (Requires a 64-bit multiply and divide):
@@ -179,10 +164,10 @@ acpi_get_timer_duration(u32 start_ticks, u32 end_ticks, u32 * time_elapsed)
* time_elapsed (microseconds) =
* (delta_ticks * ACPI_USEC_PER_SEC) / ACPI_PM_TIMER_FREQUENCY;
*/
- status = acpi_ut_short_divide(((u64)delta_ticks) * ACPI_USEC_PER_SEC,
+ status = acpi_ut_short_divide(delta_ticks * ACPI_USEC_PER_SEC,
ACPI_PM_TIMER_FREQUENCY, &quotient, NULL);
- *time_elapsed = (u32) quotient;
+ *time_elapsed = (u32)quotient;
return_ACPI_STATUS(status);
}