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-rw-r--r--arch/arm/mach-berlin/platsmp.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/arm/mach-berlin/platsmp.c b/arch/arm/mach-berlin/platsmp.c
new file mode 100644
index 0000000000..ed94758d30
--- /dev/null
+++ b/arch/arm/mach-berlin/platsmp.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2014 Marvell Technology Group Ltd.
+ *
+ * Antoine Ténart <antoine.tenart@free-electrons.com>
+ */
+
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cp15.h>
+#include <asm/page.h>
+#include <asm/smp_plat.h>
+#include <asm/smp_scu.h>
+
+/*
+ * There are two reset registers, one with self-clearing (SC)
+ * reset and one with non-self-clearing reset (NON_SC).
+ */
+#define CPU_RESET_SC 0x00
+#define CPU_RESET_NON_SC 0x20
+
+#define RESET_VECT 0x00
+#define SW_RESET_ADDR 0x94
+
+extern u32 boot_inst;
+
+static void __iomem *cpu_ctrl;
+
+static inline void berlin_perform_reset_cpu(unsigned int cpu)
+{
+ u32 val;
+
+ val = readl(cpu_ctrl + CPU_RESET_NON_SC);
+ val &= ~BIT(cpu_logical_map(cpu));
+ writel(val, cpu_ctrl + CPU_RESET_NON_SC);
+ val |= BIT(cpu_logical_map(cpu));
+ writel(val, cpu_ctrl + CPU_RESET_NON_SC);
+}
+
+static int berlin_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ if (!cpu_ctrl)
+ return -EFAULT;
+
+ /*
+ * Reset the CPU, making it to execute the instruction in the reset
+ * exception vector.
+ */
+ berlin_perform_reset_cpu(cpu);
+
+ return 0;
+}
+
+static void __init berlin_smp_prepare_cpus(unsigned int max_cpus)
+{
+ struct device_node *np;
+ void __iomem *scu_base;
+ void __iomem *vectors_base;
+
+ np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
+ scu_base = of_iomap(np, 0);
+ of_node_put(np);
+ if (!scu_base)
+ return;
+
+ np = of_find_compatible_node(NULL, NULL, "marvell,berlin-cpu-ctrl");
+ cpu_ctrl = of_iomap(np, 0);
+ of_node_put(np);
+ if (!cpu_ctrl)
+ goto unmap_scu;
+
+ vectors_base = ioremap(VECTORS_BASE, SZ_32K);
+ if (!vectors_base)
+ goto unmap_scu;
+
+ scu_enable(scu_base);
+
+ /*
+ * Write the first instruction the CPU will execute after being reset
+ * in the reset exception vector.
+ */
+ writel(boot_inst, vectors_base + RESET_VECT);
+
+ /*
+ * Write the secondary startup address into the SW reset address
+ * vector. This is used by boot_inst.
+ */
+ writel(__pa_symbol(secondary_startup), vectors_base + SW_RESET_ADDR);
+
+ iounmap(vectors_base);
+unmap_scu:
+ iounmap(scu_base);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static void berlin_cpu_die(unsigned int cpu)
+{
+ v7_exit_coherency_flush(louis);
+ while (1)
+ cpu_do_idle();
+}
+
+static int berlin_cpu_kill(unsigned int cpu)
+{
+ u32 val;
+
+ val = readl(cpu_ctrl + CPU_RESET_NON_SC);
+ val &= ~BIT(cpu_logical_map(cpu));
+ writel(val, cpu_ctrl + CPU_RESET_NON_SC);
+
+ return 1;
+}
+#endif
+
+static const struct smp_operations berlin_smp_ops __initconst = {
+ .smp_prepare_cpus = berlin_smp_prepare_cpus,
+ .smp_boot_secondary = berlin_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_die = berlin_cpu_die,
+ .cpu_kill = berlin_cpu_kill,
+#endif
+};
+CPU_METHOD_OF_DECLARE(berlin_smp, "marvell,berlin-smp", &berlin_smp_ops);