arch/arm/mach-realview/platsmp-dt.c

   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 <plat/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
  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         if (IS_ERR(map)) {
  70                 pr_err("PLATSMP: No syscon regmap\n");
  71                 return;
  72         }
  73         /* Put the boot address in this magic register */
  74         regmap_write(map, REALVIEW_SYS_FLAGSSET_OFFSET,
  75                      __pa_symbol(versatile_secondary_startup));
  76 }
  77
  78 #ifdef CONFIG_HOTPLUG_CPU
  79 static void realview_cpu_die(unsigned int cpu)
  80 {
  81         return versatile_immitation_cpu_die(cpu, 0x20);
  82 }
  83 #endif
  84
  85 static const struct smp_operations realview_dt_smp_ops __initconst = {
  86         .smp_prepare_cpus       = realview_smp_prepare_cpus,
  87         .smp_secondary_init     = versatile_secondary_init,
  88         .smp_boot_secondary     = versatile_boot_secondary,
  89 #ifdef CONFIG_HOTPLUG_CPU
  90         .cpu_die                = realview_cpu_die,
  91 #endif
  92 };
  93 CPU_METHOD_OF_DECLARE(realview_smp, "arm,realview-smp", &realview_dt_smp_ops);