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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/arm/mach-mvebu/platsmp-a9.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/mach-mvebu/platsmp-a9.c')
-rw-r--r--arch/arm/mach-mvebu/platsmp-a9.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/arch/arm/mach-mvebu/platsmp-a9.c b/arch/arm/mach-mvebu/platsmp-a9.c
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+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Symmetric Multi Processing (SMP) support for Marvell EBU Cortex-A9
+ * based SOCs (Armada 375/38x).
+ *
+ * Copyright (C) 2014 Marvell
+ *
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/smp.h>
+#include <linux/mbus.h>
+#include <asm/smp_scu.h>
+#include <asm/smp_plat.h>
+#include "common.h"
+#include "pmsu.h"
+
+extern void mvebu_cortex_a9_secondary_startup(void);
+
+static int mvebu_cortex_a9_boot_secondary(unsigned int cpu,
+ struct task_struct *idle)
+{
+ int ret, hw_cpu;
+
+ pr_info("Booting CPU %d\n", cpu);
+
+ /*
+ * Write the address of secondary startup into the system-wide
+ * flags register. The boot monitor waits until it receives a
+ * soft interrupt, and then the secondary CPU branches to this
+ * address.
+ */
+ hw_cpu = cpu_logical_map(cpu);
+ if (of_machine_is_compatible("marvell,armada375"))
+ mvebu_system_controller_set_cpu_boot_addr(mvebu_cortex_a9_secondary_startup);
+ else
+ mvebu_pmsu_set_cpu_boot_addr(hw_cpu, mvebu_cortex_a9_secondary_startup);
+ smp_wmb();
+
+ /*
+ * Doing this before deasserting the CPUs is needed to wake up CPUs
+ * in the offline state after using CPU hotplug.
+ */
+ arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+
+ ret = mvebu_cpu_reset_deassert(hw_cpu);
+ if (ret) {
+ pr_err("Could not start the secondary CPU: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+/*
+ * When a CPU is brought back online, either through CPU hotplug, or
+ * because of the boot of a kexec'ed kernel, the PMSU configuration
+ * for this CPU might be in the deep idle state, preventing this CPU
+ * from receiving interrupts. Here, we therefore take out the current
+ * CPU from this state, which was entered by armada_38x_cpu_die()
+ * below.
+ */
+static void armada_38x_secondary_init(unsigned int cpu)
+{
+ mvebu_v7_pmsu_idle_exit();
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static void armada_38x_cpu_die(unsigned int cpu)
+{
+ /*
+ * CPU hotplug is implemented by putting offline CPUs into the
+ * deep idle sleep state.
+ */
+ armada_38x_do_cpu_suspend(true);
+}
+
+/*
+ * We need a dummy function, so that platform_can_cpu_hotplug() knows
+ * we support CPU hotplug. However, the function does not need to do
+ * anything, because CPUs going offline can enter the deep idle state
+ * by themselves, without any help from a still alive CPU.
+ */
+static int armada_38x_cpu_kill(unsigned int cpu)
+{
+ return 1;
+}
+#endif
+
+static const struct smp_operations mvebu_cortex_a9_smp_ops __initconst = {
+ .smp_boot_secondary = mvebu_cortex_a9_boot_secondary,
+};
+
+static const struct smp_operations armada_38x_smp_ops __initconst = {
+ .smp_boot_secondary = mvebu_cortex_a9_boot_secondary,
+ .smp_secondary_init = armada_38x_secondary_init,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_die = armada_38x_cpu_die,
+ .cpu_kill = armada_38x_cpu_kill,
+#endif
+};
+
+CPU_METHOD_OF_DECLARE(mvebu_armada_375_smp, "marvell,armada-375-smp",
+ &mvebu_cortex_a9_smp_ops);
+CPU_METHOD_OF_DECLARE(mvebu_armada_380_smp, "marvell,armada-380-smp",
+ &armada_38x_smp_ops);
+CPU_METHOD_OF_DECLARE(mvebu_armada_390_smp, "marvell,armada-390-smp",
+ &armada_38x_smp_ops);