Thread (1 message) 1 message, 1 author, 2017-08-14

[PATCH v5 2/6] ARM: smp_scu: add a helper for powering on a specific CPU

From: linux@armlinux.org.uk (Russell King - ARM Linux)
Date: 2017-08-14 10:52:18
Also in: linux-amlogic, linux-devicetree

On Fri, Jul 28, 2017 at 11:21:34PM +0200, Martin Blumenstingl wrote:
+/*
+ * Set the executing CPUs power mode to SCU_PM_NORMAL.
+ *
+ * This function must be called with preemption disabled, and as it
+ * has the side effect of disabling coherency, caches must have been
+ * flushed. Interrupts must also have been disabled.
This comment looks rather misleading for several reasons:

1. we're bringing another CPU to normal power mode, which means it's
   coming _into_ coherency, not leaving coherency, so "side effect of
   disabling coherency" is wrong.

2. what has the state of the _local_ CPUs caches got to do with the
   remote CPU when it isn't even powered up?

Could you please reword this comment to be more accurate please - I
think the paragraph can be removed.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
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