Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c4bc34d2 authored Feb 23, 2016 by Suzuki K Poulose Committed by Catalin Marinas Feb 24, 2016

arm64: Add a helper for parking CPUs in a loop



Adds a routine which can be used to park CPUs (spinning in kernel)
when they can't be killed.

Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

parent 2b5fe07a

arch/arm64/include/asm/smp.h

+8 −0

Original line number	Diff line number	Diff line
		@@ -78,4 +78,12 @@ extern int __cpu_disable(void);
		extern void __cpu_die(unsigned int cpu);
		extern void cpu_die(void);

		static inline void cpu_park_loop(void)
		{
		for (;;) {
		wfe();
		wfi();
		}
		}

		#endif /* ifndef __ASM_SMP_H */

arch/arm64/kernel/cpufeature.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -890,10 +890,7 @@ static void fail_incapable_cpu(char *cap_type,
		/* Check if we can park ourselves */
		if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_die)
		cpu_ops[cpu]->cpu_die(cpu);
		asm(
		"1: wfe\n"
		" wfi\n"
		" b 1b");
		cpu_park_loop();
		}

		/*