xref: /openbmc/linux/arch/arm/mach-tegra/hotplug.c (revision 6774def6)
1 /*
2  *  Copyright (C) 2002 ARM Ltd.
3  *  All Rights Reserved
4  *  Copyright (c) 2010, 2012-2013, NVIDIA Corporation. All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <linux/clk/tegra.h>
12 #include <linux/kernel.h>
13 #include <linux/smp.h>
14 
15 #include <soc/tegra/common.h>
16 #include <soc/tegra/fuse.h>
17 
18 #include <asm/smp_plat.h>
19 
20 #include "sleep.h"
21 
22 static void (*tegra_hotplug_shutdown)(void);
23 
24 int tegra_cpu_kill(unsigned cpu)
25 {
26 	cpu = cpu_logical_map(cpu);
27 
28 	/* Clock gate the CPU */
29 	tegra_wait_cpu_in_reset(cpu);
30 	tegra_disable_cpu_clock(cpu);
31 
32 	return 1;
33 }
34 
35 /*
36  * platform-specific code to shutdown a CPU
37  *
38  * Called with IRQs disabled
39  */
40 void __ref tegra_cpu_die(unsigned int cpu)
41 {
42 	if (!tegra_hotplug_shutdown) {
43 		WARN(1, "hotplug is not yet initialized\n");
44 		return;
45 	}
46 
47 	/* Clean L1 data cache */
48 	tegra_disable_clean_inv_dcache(TEGRA_FLUSH_CACHE_LOUIS);
49 
50 	/* Shut down the current CPU. */
51 	tegra_hotplug_shutdown();
52 
53 	/* Should never return here. */
54 	BUG();
55 }
56 
57 static int __init tegra_hotplug_init(void)
58 {
59 	if (!IS_ENABLED(CONFIG_HOTPLUG_CPU))
60 		return 0;
61 
62 	if (!soc_is_tegra())
63 		return 0;
64 
65 	if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) && tegra_get_chip_id() == TEGRA20)
66 		tegra_hotplug_shutdown = tegra20_hotplug_shutdown;
67 	if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) && tegra_get_chip_id() == TEGRA30)
68 		tegra_hotplug_shutdown = tegra30_hotplug_shutdown;
69 	if (IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC) && tegra_get_chip_id() == TEGRA114)
70 		tegra_hotplug_shutdown = tegra30_hotplug_shutdown;
71 	if (IS_ENABLED(CONFIG_ARCH_TEGRA_124_SOC) && tegra_get_chip_id() == TEGRA124)
72 		tegra_hotplug_shutdown = tegra30_hotplug_shutdown;
73 
74 	return 0;
75 }
76 pure_initcall(tegra_hotplug_init);
77