irqchip: mips-gic: SYNC after enabling GIC region
authorJames Hogan <james.hogan@imgtec.com>
Sun, 13 Aug 2017 04:36:09 +0000 (21:36 -0700)
committerRalf Baechle <ralf@linux-mips.org>
Wed, 30 Aug 2017 11:57:29 +0000 (13:57 +0200)
commit2c0e8382386f618c85d20cb05e7cf7df8cdd382c
tree2fab7330f1de3a2b3cebebcd412e9e77a7218472
parent5af2ed36697e2a48cd7d36232212caa6240fe9bb
irqchip: mips-gic: SYNC after enabling GIC region

A SYNC is required between enabling the GIC region and actually trying
to use it, even if the first access is a read, otherwise its possible
depending on the timing (and in my case depending on the precise
alignment of certain kernel code) to hit CM bus errors on that first
access.

Add the SYNC straight after setting the GIC base.

[paul.burton@imgtec.com:
  Changes later in this series increase our likelihood of hitting this
  by reducing the amount of code that runs between enabling the GIC &
  accessing it.]

Fixes: a7057270c280 ("irqchip: mips-gic: Add device-tree support")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # 3.19.x-
Patchwork: https://patchwork.linux-mips.org/patch/17019/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
drivers/irqchip/irq-mips-gic.c