diff options
Diffstat (limited to 'arch/arm/mach-uniphier/platsmp.c')
-rw-r--r-- | arch/arm/mach-uniphier/platsmp.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/arm/mach-uniphier/platsmp.c b/arch/arm/mach-uniphier/platsmp.c new file mode 100644 index 000000000000..5943e1cb7fe1 --- /dev/null +++ b/arch/arm/mach-uniphier/platsmp.c @@ -0,0 +1,90 @@ +/* + * 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); |