[PATCH v3 06/15] ARM: mcpm: generic SMP secondary bringup and hotplug support
From: Rob Herring <hidden>
Date: 2013-01-29 20:38:57
On 01/29/2013 01:51 AM, Nicolas Pitre wrote:
quoted hunk ↗ jump to hunk
Now that the cluster power API is in place, we can use it for SMP secondary bringup and CPU hotplug in a generic fashion. Signed-off-by: Nicolas Pitre <redacted> --- arch/arm/common/Makefile | 2 +- arch/arm/common/mcpm_platsmp.c | 85 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 86 insertions(+), 1 deletion(-) create mode 100644 arch/arm/common/mcpm_platsmp.cdiff --git a/arch/arm/common/Makefile b/arch/arm/common/Makefile index c901a38c59..e1c9db45de 100644 --- a/arch/arm/common/Makefile +++ b/arch/arm/common/Makefile@@ -13,4 +13,4 @@ obj-$(CONFIG_SHARP_PARAM) += sharpsl_param.o obj-$(CONFIG_SHARP_SCOOP) += scoop.o obj-$(CONFIG_PCI_HOST_ITE8152) += it8152.o obj-$(CONFIG_ARM_TIMER_SP804) += timer-sp.o -obj-$(CONFIG_CLUSTER_PM) += mcpm_head.o mcpm_entry.o vlock.o +obj-$(CONFIG_CLUSTER_PM) += mcpm_head.o mcpm_entry.o mcpm_platsmp.o vlock.odiff --git a/arch/arm/common/mcpm_platsmp.c b/arch/arm/common/mcpm_platsmp.c new file mode 100644 index 0000000000..401298f5ee --- /dev/null +++ b/arch/arm/common/mcpm_platsmp.c@@ -0,0 +1,85 @@ +/* + * linux/arch/arm/mach-vexpress/mcpm_platsmp.c + * + * Created by: Nicolas Pitre, November 2012 + * Copyright: (C) 2012-2013 Linaro Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Code to handle secondary CPU bringup and hotplug for the cluster power API. + */ + +#include <linux/init.h> +#include <linux/smp.h> + +#include <asm/mcpm_entry.h> +#include <asm/smp_plat.h> +#include <asm/hardware/gic.h> + +static void __init simple_smp_init_cpus(void) +{ + set_smp_cross_call(gic_raise_softirq);
In case you're not aware, you might want to base this on the gic move to drivers/irqchips. It is in arm-soc now. Then you don't need this set_smp_cross_call anymore. It is now set by the gic code internally.
+}
+
+static int __cpuinit mcpm_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ unsigned int mpidr, pcpu, pcluster, ret;
+ extern void secondary_startup(void);
+
+ mpidr = cpu_logical_map(cpu);
+ pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+ pr_debug("%s: logical CPU %d is physical CPU %d cluster %d\n",
+ __func__, cpu, pcpu, pcluster);
+
+ mcpm_set_entry_vector(pcpu, pcluster, NULL);
+ ret = mcpm_cpu_power_up(pcpu, pcluster);
+ if (ret)
+ return ret;
+ mcpm_set_entry_vector(pcpu, pcluster, secondary_startup);
+ gic_raise_softirq(cpumask_of(cpu), 0);You can use arch_send_wakeup_ipi_mask here now instead. That's in 3.8-rc1.
+ dsb_sev();
+ return 0;
+}
+
+static void __cpuinit mcpm_secondary_init(unsigned int cpu)
+{
+ mcpm_cpu_powered_up();
+ gic_secondary_init(0);Catalin's gic series will remove this.
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static int mcpm_cpu_disable(unsigned int cpu)
+{
+ /*
+ * We assume all CPUs may be shut down.
+ * This would be the hook to use for eventual Secure
+ * OS migration requests as described in the PSCI spec.
+ */
+ return 0;
+}
+
+static void mcpm_cpu_die(unsigned int cpu)
+{
+ unsigned int mpidr, pcpu, pcluster;
+ mpidr = read_cpuid_mpidr();
+ pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+ mcpm_set_entry_vector(pcpu, pcluster, NULL);
+ mcpm_cpu_power_down();
+}
+
+#endif
+
+struct smp_operations __initdata mcpm_smp_ops = {
+ .smp_init_cpus = simple_smp_init_cpus,
+ .smp_boot_secondary = mcpm_boot_secondary,
+ .smp_secondary_init = mcpm_secondary_init,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_disable = mcpm_cpu_disable,
+ .cpu_die = mcpm_cpu_die,
+#endif
+};