The ARM spear machine uses the "holding pen" mechanism for starting secondary CPUs. Most implementations indicate it's a secondary core's time to start by writing its CPU id into a location and then signaling the core with a software-generated interrupt.
The spear code does not send the signal. Comments elsewhere in the code seem to indicate it should: The BootMonitor waits until it receives a soft interrupt, and then the secondary CPU branches to this address. I suspect this is an oversight, and this patch proposes a remedy. *** I need the attention of a maintainer to verify this *** because I am unable to test this proposed change. Signed-off-by: Alex Elder <el...@linaro.org> --- arch/arm/mach-spear/platsmp.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm/mach-spear/platsmp.c b/arch/arm/mach-spear/platsmp.c index 5c4a198..c9064fe 100644 --- a/arch/arm/mach-spear/platsmp.c +++ b/arch/arm/mach-spear/platsmp.c @@ -62,6 +62,8 @@ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) flush_cache_all(); outer_flush_all(); + arch_send_wakeup_ipi_mask(cpumask_of(cpu)); + timeout = jiffies + (1 * HZ); while (time_before(jiffies, timeout)) { smp_rmb(); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/