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 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); 94