xref: /openbmc/linux/arch/arm/mach-imx/hotplug.c (revision e34645f4)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2011 Freescale Semiconductor, Inc.
4  * Copyright 2011 Linaro Ltd.
5  */
6 
7 #include <linux/errno.h>
8 #include <linux/jiffies.h>
9 #include <asm/cacheflush.h>
10 #include <asm/cp15.h>
11 #include <asm/proc-fns.h>
12 
13 #include "common.h"
14 #include "hardware.h"
15 
16 /*
17  * platform-specific code to shutdown a CPU
18  *
19  * Called with IRQs disabled
20  */
imx_cpu_die(unsigned int cpu)21 void imx_cpu_die(unsigned int cpu)
22 {
23 	v7_exit_coherency_flush(louis);
24 	/*
25 	 * We use the cpu jumping argument register to sync with
26 	 * imx_cpu_kill() which is running on cpu0 and waiting for
27 	 * the register being cleared to kill the cpu.
28 	 */
29 	imx_set_cpu_arg(cpu, ~0);
30 
31 	while (1)
32 		cpu_do_idle();
33 }
34 
imx_cpu_kill(unsigned int cpu)35 int imx_cpu_kill(unsigned int cpu)
36 {
37 	unsigned long timeout = jiffies + msecs_to_jiffies(50);
38 
39 	while (imx_get_cpu_arg(cpu) == 0)
40 		if (time_after(jiffies, timeout))
41 			return 0;
42 	imx_enable_cpu(cpu, false);
43 	imx_set_cpu_arg(cpu, 0);
44 	if (cpu_is_imx7d())
45 		imx_gpcv2_set_core1_pdn_pup_by_software(true);
46 	return 1;
47 }
48