1 // SPDX-License-Identifier: GPL-2.0 1
2 /*
3 * SMP support for SoCs with SCU covered by ma
4 *
5 * Copyright (C) 2013 Magnus Damm
6 */
7 #include <linux/cpu.h>
8 #include <linux/delay.h>
9 #include <linux/init.h>
10 #include <linux/io.h>
11 #include <linux/smp.h>
12 #include <asm/cacheflush.h>
13 #include <asm/smp_plat.h>
14 #include <asm/smp_scu.h>
15 #include "common.h"
16
17
18 static phys_addr_t shmobile_scu_base_phys;
19 static void __iomem *shmobile_scu_base;
20
21 static int shmobile_scu_cpu_prepare(unsigned i
22 {
23 /* For this particular CPU register SC
24 shmobile_smp_hook(cpu, __pa_symbol(shm
25 shmobile_scu_base_ph
26 return 0;
27 }
28
29 void __init shmobile_smp_scu_prepare_cpus(phys
30 unsi
31 {
32 /* install boot code shared by all CPU
33 shmobile_boot_fn = __pa_symbol(shmobil
34
35 /* enable SCU and cache coherency on b
36 shmobile_scu_base_phys = scu_base_phys
37 shmobile_scu_base = ioremap(scu_base_p
38 scu_enable(shmobile_scu_base);
39 scu_power_mode(shmobile_scu_base, SCU_
40
41 /* Use CPU notifier for reset vector c
42 cpuhp_setup_state_nocalls(CPUHP_ARM_SH
43 "arm/shmobil
44 shmobile_scu
45 }
46
47 #ifdef CONFIG_HOTPLUG_CPU
48 void shmobile_smp_scu_cpu_die(unsigned int cpu
49 {
50 /* For this particular CPU deregister
51 shmobile_smp_hook(cpu, 0, 0);
52
53 dsb();
54 flush_cache_all();
55
56 /* disable cache coherency */
57 scu_power_mode(shmobile_scu_base, SCU_
58
59 /* jump to shared mach-shmobile sleep
60 shmobile_smp_sleep();
61 }
62
63 static int shmobile_smp_scu_psr_core_disabled(
64 {
65 unsigned long mask = SCU_PM_POWEROFF <
66
67 if ((readl(shmobile_scu_base + 8) & ma
68 return 1;
69
70 return 0;
71 }
72
73 int shmobile_smp_scu_cpu_kill(unsigned int cpu
74 {
75 int k;
76
77 /* this function is running on another
78 * here we need wait for shutdown code
79 * finish before asking SoC-specific c
80 */
81 for (k = 0; k < 1000; k++) {
82 if (shmobile_smp_scu_psr_core_
83 return 1;
84
85 mdelay(1);
86 }
87
88 return 0;
89 }
90 #endif
91
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