From: 陈亮 <cl@rock-chips.com>
Date: Wed, 18 Jun 2014 12:15:42 +0000 (-0700)
Subject: ddr_freq: fix Division by zero in kernel
X-Git-Tag: firefly_0821_release~5071
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=1b8f13ca4cbf3fbd532419f8c31618c81adffa3a;p=firefly-linux-kernel-4.4.55.git

ddr_freq: fix Division by zero in kernel
---

diff --git a/arch/arm/mach-rockchip/ddr_freq.c b/arch/arm/mach-rockchip/ddr_freq.c
index a68c703b6807..2cf82297e646 100644
--- a/arch/arm/mach-rockchip/ddr_freq.c
+++ b/arch/arm/mach-rockchip/ddr_freq.c
@@ -282,6 +282,8 @@ void ddr_bandwidth_get(struct ddr_bw_info *ddr_bw_ch0, struct ddr_bw_info *ddr_b
 	        	ddr_bw_val[j][i] = grf_readl(RK3288_GRF_SOC_STATUS11+i*4+j*16);
 		}
 	}
+	if (!ddr_bw_val[0][ddrbw_time_num])
+		goto end;
 
 	if (ddr_bw_ch0) {
 		ddr_freq = readl_relaxed(RK_DDR_VIRT + 0xc0);
@@ -320,7 +322,7 @@ void ddr_bandwidth_get(struct ddr_bw_info *ddr_bw_ch0, struct ddr_bw_info *ddr_b
 		ddr_bw_ch0->vio1 = ddr_bw_ch0->vio1*ddr_freq/ddr_bw_val[0][ddrbw_time_num];
 		ddr_bw_ch0->vio2 = ddr_bw_ch0->vio2*ddr_freq/ddr_bw_val[0][ddrbw_time_num];
 	}
-	
+end:
 	ddr_monitor_start();
 }