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