Secondary cores should enter a low-power idle state when waiting to
be started. The "wfe" instruction causes a core to wait until an event
or interrupt arrives before continuing to the next instruction, and
the "sev" instruction sends a wakeup event to the other cores.
Add an "sev" (and a memory barrier) to bcm2836_boot_secondary, the
function that wakes the waiting cores during booting. This is required
if the secondary cores are sitting in "wfe", and harmless if not.
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
writel(virt_to_phys(secondary_startup),
intc_base + LOCAL_MAILBOX3_SET0 + 16 * cpu);
+ dsb(sy);
+ sev();
+
iounmap(intc_base);
return 0;