sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

arm/qemu: use WFI to avoid busy loop

Browse Source 
This adds WFI based up_idle() for arm/qemu to fix busy loop.

Signed-off-by: Yanfeng Liu <yfliu2008@qq.com>
This commit is contained in:
Yanfeng Liu 2024-08-23 12:47:49 +08:00 committed by Xiang Xiao
parent 93b520f7b0
commit 74080e8659
4 changed files with 65 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/arm/Kconfig
View File

@ -657,6 +657,7 @@ config ARCH_CHIP_QEMU_ARM
select ARCH_HAVE_PSCI
select ARCH_HAVE_POWEROFF
select ARCH_HAVE_RESET
select ARCH_IDLE_CUSTOM
---help---
QEMU virt platform (ARMv7a)

3
arch/arm/src/qemu/CMakeLists.txt
View File

@ -18,7 +18,8 @@
#
# ##############################################################################
set(SRCS qemu_boot.c qemu_serial.c qemu_irq.c qemu_timer.c qemu_memorymap.c)
set(SRCS qemu_boot.c qemu_serial.c qemu_irq.c qemu_timer.c qemu_memorymap.c
qemu_idle.c)
if(CONFIG_SMP)
list(APPEND SRCS qemu_cpuboot.c)

1
arch/arm/src/qemu/Make.defs
View File

@ -22,6 +22,7 @@ include armv7-a/Make.defs
# qemu-specific C source files
CHIP_CSRCS = qemu_boot.c qemu_serial.c qemu_irq.c qemu_timer.c qemu_memorymap.c
CHIP_CSRCS += qemu_idle.c
ifeq ($(CONFIG_SMP),y)
CHIP_CSRCS += qemu_cpuboot.c

61
arch/arm/src/qemu/qemu_idle.c Normal file
View File

@ -0,0 +1,61 @@
/****************************************************************************
* arch/arm/src/qemu/qemu_idle.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/arch.h>
#include "arm_internal.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_idle
*
* Description:
* up_idle() is the logic that will be executed when there is no other
* ready-to-run task. This is processor idle time and will continue until
* some interrupt occurs to cause a context switch from the idle task.
*
* Processing in this state may be processor-specific. e.g., this is where
* power management operations might be performed.
*
****************************************************************************/
void up_idle(void)
{
#if defined(CONFIG_SUPPRESS_INTERRUPTS) || defined(CONFIG_SUPPRESS_TIMER_INTS)
/* If the system is idle and there are no timer interrupts, then process
* "fake" timer interrupts. Hopefully, something will wake up.
*/
nxsched_process_timer();
#else
/* Sleep until an interrupt occurs to save power */
asm("WFI");
#endif
}