diff options
Diffstat (limited to 'arch/arm/kernel')
| -rw-r--r-- | arch/arm/kernel/devtree.c | 10 | ||||
| -rw-r--r-- | arch/arm/kernel/machine_kexec.c | 4 | ||||
| -rw-r--r-- | arch/arm/kernel/process.c | 44 | ||||
| -rw-r--r-- | arch/arm/kernel/setup.c | 2 | ||||
| -rw-r--r-- | arch/arm/kernel/smp.c | 15 | ||||
| -rw-r--r-- | arch/arm/kernel/topology.c | 2 |
6 files changed, 52 insertions, 25 deletions
diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c index 5af04f6daa33..5859c8bc727c 100644 --- a/arch/arm/kernel/devtree.c +++ b/arch/arm/kernel/devtree.c @@ -82,7 +82,7 @@ void __init arm_dt_init_cpu_maps(void) u32 i, j, cpuidx = 1; u32 mpidr = is_smp() ? read_cpuid_mpidr() & MPIDR_HWID_BITMASK : 0; - u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = UINT_MAX }; + u32 tmp_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID }; bool bootcpu_valid = false; cpus = of_find_node_by_path("/cpus"); @@ -92,6 +92,9 @@ void __init arm_dt_init_cpu_maps(void) for_each_child_of_node(cpus, cpu) { u32 hwid; + if (of_node_cmp(cpu->type, "cpu")) + continue; + pr_debug(" * %s...\n", cpu->full_name); /* * A device tree containing CPU nodes with missing "reg" @@ -149,9 +152,10 @@ void __init arm_dt_init_cpu_maps(void) tmp_map[i] = hwid; } - if (WARN(!bootcpu_valid, "DT missing boot CPU MPIDR[23:0], " - "fall back to default cpu_logical_map\n")) + if (!bootcpu_valid) { + pr_warn("DT missing boot CPU MPIDR[23:0], fall back to default cpu_logical_map\n"); return; + } /* * Since the boot CPU node contains proper data, and all nodes have diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c index 8ef8c9337809..4fb074c446bf 100644 --- a/arch/arm/kernel/machine_kexec.c +++ b/arch/arm/kernel/machine_kexec.c @@ -134,6 +134,10 @@ void machine_kexec(struct kimage *image) unsigned long reboot_code_buffer_phys; void *reboot_code_buffer; + if (num_online_cpus() > 1) { + pr_err("kexec: error: multiple CPUs still online\n"); + return; + } page_list = image->head & PAGE_MASK; diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index f21970316836..6e8931ccf13e 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -184,30 +184,61 @@ int __init reboot_setup(char *str) __setup("reboot=", reboot_setup); +/* + * Called by kexec, immediately prior to machine_kexec(). + * + * This must completely disable all secondary CPUs; simply causing those CPUs + * to execute e.g. a RAM-based pin loop is not sufficient. This allows the + * kexec'd kernel to use any and all RAM as it sees fit, without having to + * avoid any code or data used by any SW CPU pin loop. The CPU hotplug + * functionality embodied in disable_nonboot_cpus() to achieve this. + */ void machine_shutdown(void) { -#ifdef CONFIG_SMP - smp_send_stop(); -#endif + disable_nonboot_cpus(); } +/* + * Halting simply requires that the secondary CPUs stop performing any + * activity (executing tasks, handling interrupts). smp_send_stop() + * achieves this. + */ void machine_halt(void) { - machine_shutdown(); + smp_send_stop(); + local_irq_disable(); while (1); } +/* + * Power-off simply requires that the secondary CPUs stop performing any + * activity (executing tasks, handling interrupts). smp_send_stop() + * achieves this. When the system power is turned off, it will take all CPUs + * with it. + */ void machine_power_off(void) { - machine_shutdown(); + smp_send_stop(); + if (pm_power_off) pm_power_off(); } +/* + * Restart requires that the secondary CPUs stop performing any activity + * while the primary CPU resets the system. Systems with a single CPU can + * use soft_restart() as their machine descriptor's .restart hook, since that + * will cause the only available CPU to reset. Systems with multiple CPUs must + * provide a HW restart implementation, to ensure that all CPUs reset at once. + * This is required so that any code running after reset on the primary CPU + * doesn't have to co-ordinate with other CPUs to ensure they aren't still + * executing pre-reset code, and using RAM that the primary CPU's code wishes + * to use. Implementing such co-ordination would be essentially impossible. + */ void machine_restart(char *cmd) { - machine_shutdown(); + smp_send_stop(); arm_pm_restart(reboot_mode, cmd); @@ -411,7 +442,6 @@ static struct vm_area_struct gate_vma = { .vm_start = 0xffff0000, .vm_end = 0xffff0000 + PAGE_SIZE, .vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC, - .vm_mm = &init_mm, }; static int __init gate_vma_init(void) diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 1522c7ae31b0..b4b1d397592b 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -444,7 +444,7 @@ void notrace cpu_init(void) : "r14"); } -int __cpu_logical_map[NR_CPUS]; +u32 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = MPIDR_INVALID }; void __init smp_setup_processor_id(void) { diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 47ab90563bf4..5919eb451bb9 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -251,7 +251,7 @@ void __ref cpu_die(void) * this returns, power and/or clocks can be removed at any point * from this CPU and its cache by platform_cpu_kill(). */ - RCU_NONIDLE(complete(&cpu_died)); + complete(&cpu_died); /* * Ensure that the cache lines associated with that completion are @@ -651,17 +651,6 @@ void smp_send_reschedule(int cpu) smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE); } -#ifdef CONFIG_HOTPLUG_CPU -static void smp_kill_cpus(cpumask_t *mask) -{ - unsigned int cpu; - for_each_cpu(cpu, mask) - platform_cpu_kill(cpu); -} -#else -static void smp_kill_cpus(cpumask_t *mask) { } -#endif - void smp_send_stop(void) { unsigned long timeout; @@ -679,8 +668,6 @@ void smp_send_stop(void) if (num_online_cpus() > 1) pr_warning("SMP: failed to stop secondary CPUs\n"); - - smp_kill_cpus(&mask); } /* diff --git a/arch/arm/kernel/topology.c b/arch/arm/kernel/topology.c index f10316b4ecdc..c5a59546a256 100644 --- a/arch/arm/kernel/topology.c +++ b/arch/arm/kernel/topology.c @@ -13,6 +13,7 @@ #include <linux/cpu.h> #include <linux/cpumask.h> +#include <linux/export.h> #include <linux/init.h> #include <linux/percpu.h> #include <linux/node.h> @@ -200,6 +201,7 @@ static inline void update_cpu_power(unsigned int cpuid, unsigned int mpidr) {} * cpu topology table */ struct cputopo_arm cpu_topology[NR_CPUS]; +EXPORT_SYMBOL_GPL(cpu_topology); const struct cpumask *cpu_coregroup_mask(int cpu) { |