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-rw-r--r--kernel/arch/arm/mach-mvebu/cpu-reset.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-mvebu/cpu-reset.c b/kernel/arch/arm/mach-mvebu/cpu-reset.c
new file mode 100644
index 000000000..4a2cadd6b
--- /dev/null
+++ b/kernel/arch/arm/mach-mvebu/cpu-reset.c
@@ -0,0 +1,102 @@
+/*
+ * 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>
+
+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;
+}
+
+static 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);