From: Gary King <gking@nvidia.com>
Date: Thu, 19 Aug 2010 21:08:38 +0000 (-0700)
Subject: [ARM] tegra: smp: add barrier before raising GIC IPI IRQ
X-Git-Tag: firefly_0821_release~9833^2~358
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=1994d98dc3bcbb9dea85db2b58118a59ac2652f5;p=firefly-linux-kernel-4.4.55.git

[ARM] tegra: smp: add barrier before raising GIC IPI IRQ

since the GIC registers are device memory and the IPI data is
stored in normal memory, a simple dmb is insufficient to ensure
that the data will be visible to the IPI-receiving processor
prior to the IPI handler running

Change-Id: Idaddd9f225d00ebd3a8d656fa75c401323b80138
Signed-off-by: Gary King <gking@nvidia.com>
---

diff --git a/arch/arm/mach-tegra/include/mach/smp.h b/arch/arm/mach-tegra/include/mach/smp.h
index 8b42dab79a70..cd6a3fc567f1 100644
--- a/arch/arm/mach-tegra/include/mach/smp.h
+++ b/arch/arm/mach-tegra/include/mach/smp.h
@@ -17,6 +17,7 @@
  */
 static inline void smp_cross_call(const struct cpumask *mask)
 {
+	dsb();
 	gic_raise_softirq(mask, 1);
 }