1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2015 Linus Walleij
4 */
5 #include <linux/smp.h>
6 #include <linux/io.h>
7 #include <linux/of.h>
8 #include <linux/of_address.h>
9 #include <linux/regmap.h>
10 #include <linux/mfd/syscon.h>
11
12 #include <asm/cacheflush.h>
13 #include <asm/smp_plat.h>
14 #include <asm/smp_scu.h>
15
16 #include "platsmp.h"
17
18 #define REALVIEW_SYS_FLAGSSET_OFFSET 0x30
19
20 static const struct of_device_id realview_scu_match[] = {
21 { .compatible = "arm,arm11mp-scu", },
22 { .compatible = "arm,cortex-a9-scu", },
23 { .compatible = "arm,cortex-a5-scu", },
24 { }
25 };
26
27 static const struct of_device_id realview_syscon_match[] = {
28 { .compatible = "arm,core-module-integrator", },
29 { .compatible = "arm,realview-eb-syscon", },
30 { .compatible = "arm,realview-pb11mp-syscon", },
31 { .compatible = "arm,realview-pbx-syscon", },
32 { },
33 };
34
realview_smp_prepare_cpus(unsigned int max_cpus)35 static void __init realview_smp_prepare_cpus(unsigned int max_cpus)
36 {
37 struct device_node *np;
38 void __iomem *scu_base;
39 struct regmap *map;
40 unsigned int ncores;
41 int i;
42
43 np = of_find_matching_node(NULL, realview_scu_match);
44 if (!np) {
45 pr_err("PLATSMP: No SCU base address\n");
46 return;
47 }
48 scu_base = of_iomap(np, 0);
49 of_node_put(np);
50 if (!scu_base) {
51 pr_err("PLATSMP: No SCU remap\n");
52 return;
53 }
54
55 scu_enable(scu_base);
56 ncores = scu_get_core_count(scu_base);
57 pr_info("SCU: %d cores detected\n", ncores);
58 for (i = 0; i < ncores; i++)
59 set_cpu_possible(i, true);
60 iounmap(scu_base);
61
62 /* The syscon contains the magic SMP start address registers */
63 np = of_find_matching_node(NULL, realview_syscon_match);
64 if (!np) {
65 pr_err("PLATSMP: No syscon match\n");
66 return;
67 }
68 map = syscon_node_to_regmap(np);
69 of_node_put(np);
70 if (IS_ERR(map)) {
71 pr_err("PLATSMP: No syscon regmap\n");
72 return;
73 }
74 /* Put the boot address in this magic register */
75 regmap_write(map, REALVIEW_SYS_FLAGSSET_OFFSET,
76 __pa_symbol(versatile_secondary_startup));
77 }
78
79 #ifdef CONFIG_HOTPLUG_CPU
realview_cpu_die(unsigned int cpu)80 static void realview_cpu_die(unsigned int cpu)
81 {
82 return versatile_immitation_cpu_die(cpu, 0x20);
83 }
84 #endif
85
86 static const struct smp_operations realview_dt_smp_ops __initconst = {
87 .smp_prepare_cpus = realview_smp_prepare_cpus,
88 .smp_secondary_init = versatile_secondary_init,
89 .smp_boot_secondary = versatile_boot_secondary,
90 #ifdef CONFIG_HOTPLUG_CPU
91 .cpu_die = realview_cpu_die,
92 #endif
93 };
94 CPU_METHOD_OF_DECLARE(realview_smp, "arm,realview-smp", &realview_dt_smp_ops);
95