diff options
Diffstat (limited to 'arch/arm/mach-mvebu/cpu-reset.c')
-rw-r--r-- | arch/arm/mach-mvebu/cpu-reset.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/arch/arm/mach-mvebu/cpu-reset.c b/arch/arm/mach-mvebu/cpu-reset.c new file mode 100644 index 0000000..4a8f9ee --- /dev/null +++ b/arch/arm/mach-mvebu/cpu-reset.c @@ -0,0 +1,103 @@ +/* + * Copyright (C) 2014 Marvell + * + * Thomas Petazzoni <thomas.petazzoni@free-electrons.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#define pr_fmt(fmt) "mvebu-cpureset: " fmt + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/of_address.h> +#include <linux/io.h> +#include <linux/resource.h> +#include "armada-370-xp.h" + +static void __iomem *cpu_reset_base; +static size_t cpu_reset_size; + +#define CPU_RESET_OFFSET(cpu) (cpu * 0x8) +#define CPU_RESET_ASSERT BIT(0) + +int mvebu_cpu_reset_deassert(int cpu) +{ + u32 reg; + + if (!cpu_reset_base) + return -ENODEV; + + if (CPU_RESET_OFFSET(cpu) >= cpu_reset_size) + return -EINVAL; + + reg = readl(cpu_reset_base + CPU_RESET_OFFSET(cpu)); + reg &= ~CPU_RESET_ASSERT; + writel(reg, cpu_reset_base + CPU_RESET_OFFSET(cpu)); + + return 0; +} + +static int mvebu_cpu_reset_map(struct device_node *np, int res_idx) +{ + struct resource res; + + if (of_address_to_resource(np, res_idx, &res)) { + pr_err("unable to get resource\n"); + return -ENOENT; + } + + if (!request_mem_region(res.start, resource_size(&res), + np->full_name)) { + pr_err("unable to request region\n"); + return -EBUSY; + } + + cpu_reset_base = ioremap(res.start, resource_size(&res)); + if (!cpu_reset_base) { + pr_err("unable to map registers\n"); + release_mem_region(res.start, resource_size(&res)); + return -ENOMEM; + } + + cpu_reset_size = resource_size(&res); + + return 0; +} + +int __init mvebu_cpu_reset_init(void) +{ + struct device_node *np; + int res_idx; + int ret; + + np = of_find_compatible_node(NULL, NULL, + "marvell,armada-370-cpu-reset"); + if (np) { + res_idx = 0; + } else { + /* + * This code is kept for backward compatibility with + * old Device Trees. + */ + np = of_find_compatible_node(NULL, NULL, + "marvell,armada-370-xp-pmsu"); + if (np) { + pr_warn(FW_WARN "deprecated pmsu binding\n"); + res_idx = 1; + } + } + + /* No reset node found */ + if (!np) + return -ENODEV; + + ret = mvebu_cpu_reset_map(np, res_idx); + of_node_put(np); + + return ret; +} + +early_initcall(mvebu_cpu_reset_init); |