From: Vineet Gupta <vgupta@synopsys.com>
Date: Mon, 13 Jun 2016 14:38:27 +0000 (+0200)
Subject: ARC: Elide redundant setup of DMA callbacks
X-Git-Tag: firefly_0821_release~176^2~4^2~31^2~231
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=03551c85c1c01bf7ec58218a2afb225d98da0b97;p=firefly-linux-kernel-4.4.55.git

ARC: Elide redundant setup of DMA callbacks

commit 45c3b08a117e2232fc8d7b9e849ead36386f4f96 upstream.

For resources shared by all cores such as SLC and IOC, only the master
core needs to do any setups / enabling / disabling etc.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c
index ff7ff6cbb811..aaf1e2d1d900 100644
--- a/arch/arc/mm/cache.c
+++ b/arch/arc/mm/cache.c
@@ -914,6 +914,15 @@ void arc_cache_init(void)
 
 	printk(arc_cache_mumbojumbo(0, str, sizeof(str)));
 
+	/*
+	 * Only master CPU needs to execute rest of function:
+	 *  - Assume SMP so all cores will have same cache config so
+	 *    any geomtry checks will be same for all
+	 *  - IOC setup / dma callbacks only need to be setup once
+	 */
+	if (cpu)
+		return;
+
 	if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE)) {
 		struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache;