1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * CPU hotplug support for CSR Marco dual-core SMP SoCs
4  *
5  * Copyright (c) 2012 Cambridge Silicon Radio Limited, a CSR plc group company.
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/errno.h>
10 #include <linux/smp.h>
11 
12 #include <asm/smp_plat.h>
13 #include "common.h"
14 
platform_do_lowpower(unsigned int cpu)15 static inline void platform_do_lowpower(unsigned int cpu)
16 {
17 	/* we put the platform to just WFI */
18 	for (;;) {
19 		__asm__ __volatile__("dsb\n\t" "wfi\n\t"
20 			: : : "memory");
21 		if (prima2_pen_release == cpu_logical_map(cpu)) {
22 			/*
23 			 * OK, proper wakeup, we're done
24 			 */
25 			break;
26 		}
27 	}
28 }
29 
30 /*
31  * platform-specific code to shutdown a CPU
32  *
33  * Called with IRQs disabled
34  */
sirfsoc_cpu_die(unsigned int cpu)35 void sirfsoc_cpu_die(unsigned int cpu)
36 {
37 	platform_do_lowpower(cpu);
38 }
39