| /* |
| * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #include <linux/sizes.h> |
| #include <linux/compiler.h> |
| #include <linux/init.h> |
| #include <linux/io.h> |
| #include <linux/regmap.h> |
| #include <linux/mfd/syscon.h> |
| #include <asm/smp.h> |
| #include <asm/smp_scu.h> |
| |
| static struct regmap *sbcm_regmap; |
| |
| static void __init uniphier_smp_prepare_cpus(unsigned int max_cpus) |
| { |
| static cpumask_t only_cpu_0 = { CPU_BITS_CPU0 }; |
| unsigned long scu_base_phys = 0; |
| void __iomem *scu_base; |
| |
| sbcm_regmap = syscon_regmap_lookup_by_compatible( |
| "socionext,uniphier-system-bus-controller-misc"); |
| if (IS_ERR(sbcm_regmap)) { |
| pr_err("failed to regmap system-bus-controller-misc\n"); |
| goto err; |
| } |
| |
| if (scu_a9_has_base()) |
| scu_base_phys = scu_a9_get_base(); |
| |
| if (!scu_base_phys) { |
| pr_err("failed to get scu base\n"); |
| goto err; |
| } |
| |
| scu_base = ioremap(scu_base_phys, SZ_128); |
| if (!scu_base) { |
| pr_err("failed to remap scu base (0x%08lx)\n", scu_base_phys); |
| goto err; |
| } |
| |
| scu_enable(scu_base); |
| iounmap(scu_base); |
| |
| return; |
| err: |
| pr_warn("disabling SMP\n"); |
| init_cpu_present(&only_cpu_0); |
| sbcm_regmap = NULL; |
| } |
| |
| static void __naked uniphier_secondary_startup(void) |
| { |
| asm("bl v7_invalidate_l1\n" |
| "b secondary_startup\n"); |
| }; |
| |
| static int uniphier_boot_secondary(unsigned int cpu, |
| struct task_struct *idle) |
| { |
| int ret; |
| |
| if (!sbcm_regmap) |
| return -ENODEV; |
| |
| ret = regmap_write(sbcm_regmap, 0x1208, |
| virt_to_phys(uniphier_secondary_startup)); |
| if (!ret) |
| asm("sev"); /* wake up secondary CPU */ |
| |
| return ret; |
| } |
| |
| struct smp_operations uniphier_smp_ops __initdata = { |
| .smp_prepare_cpus = uniphier_smp_prepare_cpus, |
| .smp_boot_secondary = uniphier_boot_secondary, |
| }; |
| CPU_METHOD_OF_DECLARE(uniphier_smp, "socionext,uniphier-smp", |
| &uniphier_smp_ops); |