diff options
| author | Helge Deller <deller@gmx.de> | 2022-03-25 14:27:21 +0100 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2022-03-29 21:37:12 +0200 |
| commit | 98903688e6106d9ca68e44c7d218e61336d54631 (patch) | |
| tree | b8b4319190cb9ce7ea93283073c99a8fd1f8a1fa /arch/parisc | |
| parent | 88b3aac6228baaac6a3bcc0808845083b9d9f08f (diff) | |
| download | linux-next-98903688e6106d9ca68e44c7d218e61336d54631.tar.gz | |
parisc: Rewrite arch_cpu_idle_dead() for CPU hotplugging
Let the PDC firmware put the CPU into firmware idle loop with the
pdc_cpu_rendezvous() function.
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc')
| -rw-r--r-- | arch/parisc/kernel/process.c | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c index 2030c77592d3..28b6a2a5574c 100644 --- a/arch/parisc/kernel/process.c +++ b/arch/parisc/kernel/process.c @@ -38,6 +38,7 @@ #include <linux/rcupdate.h> #include <linux/random.h> #include <linux/nmi.h> +#include <linux/sched/hotplug.h> #include <asm/io.h> #include <asm/asm-offsets.h> @@ -46,6 +47,7 @@ #include <asm/pdc_chassis.h> #include <asm/unwind.h> #include <asm/sections.h> +#include <asm/cacheflush.h> #define COMMAND_GLOBAL F_EXTEND(0xfffe0030) #define CMD_RESET 5 /* reset any module */ @@ -158,10 +160,29 @@ void release_thread(struct task_struct *dead_task) int running_on_qemu __ro_after_init; EXPORT_SYMBOL(running_on_qemu); -void __cpuidle arch_cpu_idle_dead(void) +/* + * Called from the idle thread for the CPU which has been shutdown. + */ +void arch_cpu_idle_dead(void) { - /* nop on real hardware, qemu will offline CPU. */ - asm volatile("or %%r31,%%r31,%%r31\n":::); +#ifdef CONFIG_HOTPLUG_CPU + idle_task_exit(); + + local_irq_disable(); + + /* Tell __cpu_die() that this CPU is now safe to dispose of. */ + (void)cpu_report_death(); + + /* Ensure that the cache lines are written out. */ + flush_cache_all_local(); + flush_tlb_all_local(NULL); + + /* Let PDC firmware put CPU into firmware idle loop. */ + __pdc_cpu_rendezvous(); + + pr_warn("PDC does not provide rendezvous function.\n"); +#endif + while (1); } void __cpuidle arch_cpu_idle(void) |