// SPDX-License-Identifier: GPL-2.0-or-later/* * Idle daemon for PowerPC.  Idle daemon will handle any action * that needs to be taken when the system becomes idle. * * Originally written by Cort Dougan (cort@cs.nmt.edu). * Subsequent 32-bit hacking by Tom Rini, Armin Kuster, * Paul Mackerras and others. * * iSeries supported added by Mike Corrigan <mikejc@us.ibm.com> * * Additional shared processor, SMT, and firmware support *    Copyright (c) 2003 Dave Engebretsen <engebret@us.ibm.com> * * 32-bit and 64-bit versions merged by Paul Mackerras <paulus@samba.org> */ #include <linux/sched.h>#include <linux/kernel.h>#include <linux/smp.h>#include <linux/cpu.h>#include <linux/sysctl.h>#include <linux/tick.h> #include <asm/processor.h>#include <asm/cputable.h>#include <asm/time.h>#include <asm/machdep.h>#include <asm/runlatch.h>#include <asm/smp.h>  unsigned long cpuidle_disable = IDLE_NO_OVERRIDE;EXPORT_SYMBOL(cpuidle_disable); static int __init powersave_off(char *arg){	ppc_md.power_save = NULL;	cpuidle_disable = IDLE_POWERSAVE_OFF;	return 1;}__setup("powersave=off", powersave_off); void arch_cpu_idle(void){	ppc64_runlatch_off(); 	if (ppc_md.power_save) {		ppc_md.power_save();		/*		 * Some power_save functions return with		 * interrupts enabled, some don't.		 */		if (!irqs_disabled())			raw_local_irq_disable();	} else {		/*		 * Go into low thread priority and possibly		 * low power mode.		 */		HMT_low();		HMT_very_low();	} 	HMT_medium();	ppc64_runlatch_on();} int powersave_nap; #ifdef CONFIG_PPC_970_NAPvoid power4_idle(void){	if (!cpu_has_feature(CPU_FTR_CAN_NAP))		return; 	if (!powersave_nap)		return; 	if (!prep_irq_for_idle())		return; 	if (cpu_has_feature(CPU_FTR_ALTIVEC))		asm volatile(PPC_DSSALL " ; sync" ::: "memory"); 	power4_idle_nap(); 	/*	 * power4_idle_nap returns with interrupts enabled (soft and hard).	 * to our caller with interrupts enabled (soft and hard). Our caller	 * can cope with either interrupts disabled or enabled upon return.	 */}#endif #ifdef CONFIG_SYSCTL/* * Register the sysctl to set/clear powersave_nap. */static const struct ctl_table powersave_nap_ctl_table[] = {	{		.procname	= "powersave-nap",		.data		= &powersave_nap,		.maxlen		= sizeof(int),		.mode		= 0644,		.proc_handler	= proc_dointvec,	},}; static int __initregister_powersave_nap_sysctl(void){	register_sysctl("kernel", powersave_nap_ctl_table); 	return 0;}__initcall(register_powersave_nap_sysctl);#endif