| Masahiro Yamada | ba56a98 | 2015-05-08 13:07:11 +0900 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com> |
| 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 as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | */ |
| 14 | |
| 15 | #include <linux/sizes.h> |
| 16 | #include <linux/compiler.h> |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/io.h> |
| 19 | #include <linux/regmap.h> |
| 20 | #include <linux/mfd/syscon.h> |
| 21 | #include <asm/smp.h> |
| 22 | #include <asm/smp_scu.h> |
| 23 | |
| 24 | static struct regmap *sbcm_regmap; |
| 25 | |
| 26 | static void __init uniphier_smp_prepare_cpus(unsigned int max_cpus) |
| 27 | { |
| 28 | static cpumask_t only_cpu_0 = { CPU_BITS_CPU0 }; |
| 29 | unsigned long scu_base_phys = 0; |
| 30 | void __iomem *scu_base; |
| 31 | |
| 32 | sbcm_regmap = syscon_regmap_lookup_by_compatible( |
| 33 | "socionext,uniphier-system-bus-controller-misc"); |
| 34 | if (IS_ERR(sbcm_regmap)) { |
| 35 | pr_err("failed to regmap system-bus-controller-misc\n"); |
| 36 | goto err; |
| 37 | } |
| 38 | |
| 39 | if (scu_a9_has_base()) |
| 40 | scu_base_phys = scu_a9_get_base(); |
| 41 | |
| 42 | if (!scu_base_phys) { |
| 43 | pr_err("failed to get scu base\n"); |
| 44 | goto err; |
| 45 | } |
| 46 | |
| 47 | scu_base = ioremap(scu_base_phys, SZ_128); |
| 48 | if (!scu_base) { |
| 49 | pr_err("failed to remap scu base (0x%08lx)\n", scu_base_phys); |
| 50 | goto err; |
| 51 | } |
| 52 | |
| 53 | scu_enable(scu_base); |
| 54 | iounmap(scu_base); |
| 55 | |
| 56 | return; |
| 57 | err: |
| 58 | pr_warn("disabling SMP\n"); |
| 59 | init_cpu_present(&only_cpu_0); |
| 60 | sbcm_regmap = NULL; |
| 61 | } |
| 62 | |
| 63 | static void __naked uniphier_secondary_startup(void) |
| 64 | { |
| 65 | asm("bl v7_invalidate_l1\n" |
| 66 | "b secondary_startup\n"); |
| 67 | }; |
| 68 | |
| 69 | static int uniphier_boot_secondary(unsigned int cpu, |
| 70 | struct task_struct *idle) |
| 71 | { |
| 72 | int ret; |
| 73 | |
| 74 | if (!sbcm_regmap) |
| 75 | return -ENODEV; |
| 76 | |
| 77 | ret = regmap_write(sbcm_regmap, 0x1208, |
| 78 | virt_to_phys(uniphier_secondary_startup)); |
| 79 | if (!ret) |
| 80 | asm("sev"); /* wake up secondary CPU */ |
| 81 | |
| 82 | return ret; |
| 83 | } |
| 84 | |
| 85 | struct smp_operations uniphier_smp_ops __initdata = { |
| 86 | .smp_prepare_cpus = uniphier_smp_prepare_cpus, |
| 87 | .smp_boot_secondary = uniphier_boot_secondary, |
| 88 | }; |
| 89 | CPU_METHOD_OF_DECLARE(uniphier_smp, "socionext,uniphier-smp", |
| 90 | &uniphier_smp_ops); |