From 1f6236f06b1bb219492d7ae3c17232090128da2c Mon Sep 17 00:00:00 2001 From: York Sun Date: Thu, 12 Nov 2015 12:38:21 -0800 Subject: [PATCH] armv8: fsl-layerscape: Fix "cpu release" command When one core is released, other cores may not have valid entry address. Those cores are trapped by "wfe" and wait for further instruction. When their address is set, they need to be kicked off by "sev". Signed-off-by: York Sun --- arch/arm/cpu/armv8/fsl-layerscape/mp.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/arm/cpu/armv8/fsl-layerscape/mp.c b/arch/arm/cpu/armv8/fsl-layerscape/mp.c index 0d600db090..df7ffb88f6 100644 --- a/arch/arm/cpu/armv8/fsl-layerscape/mp.c +++ b/arch/arm/cpu/armv8/fsl-layerscape/mp.c @@ -192,6 +192,12 @@ int cpu_release(int nr, int argc, char * const argv[]) (unsigned long)table + SPIN_TABLE_ELEM_SIZE); asm volatile("dsb st"); smp_kick_all_cpus(); /* only those with entry addr set will run */ + /* + * When the first release command runs, all cores are set to go. Those + * without a valid entry address will be trapped by "wfe". "sev" kicks + * them off to check the address again. When set, they continue to run. + */ + asm volatile("sev"); return 0; }