vexpress/spc: fix a build warning on array bounds

With ARCH_VEXPRESS_SPC option, kernel build has the following
warning:

arch/arm/mach-vexpress/spc.c: In function ‘ve_spc_clk_init’:
arch/arm/mach-vexpress/spc.c:431:38: warning: array subscript is below array bounds [-Warray-bounds]
  struct ve_spc_opp *opps = info->opps[cluster];
                                      ^
since 'cluster' maybe '-1' in UP system. This patch does a active
checking to fix this issue.

Signed-off-by: Alex Shi <alex.shi@linaro.org>
Acked-by: Pawel Moll <pawel.moll@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

1 files changed, 11 insertions, 3 deletions

diff --git a/arch/arm/mach-vexpress/spc.c b/arch/arm/mach-vexpress/spc.c
index 2c2754e79cb3..f61158c6ce71 100644
--- a/arch/arm/mach-vexpress/spc.c
+++ b/arch/arm/mach-vexpress/spc.c
@@ -426,9 +426,15 @@ static int ve_spc_populate_opps(uint32_t cluster)
 
 static int ve_init_opp_table(struct device *cpu_dev)
 {
-        int cluster = topology_physical_package_id(cpu_dev->id);
-        int idx, ret = 0, max_opp = info->num_opps[cluster];
-        struct ve_spc_opp *opps = info->opps[cluster];
+        int cluster;
+        int idx, ret = 0, max_opp;
+        struct ve_spc_opp *opps;
+
+        cluster = topology_physical_package_id(cpu_dev->id);
+        cluster = cluster < 0 ? 0 : cluster;
+
+        max_opp = info->num_opps[cluster];
+        opps = info->opps[cluster];
 
         for (idx = 0; idx < max_opp; idx++, opps++) {
                 ret = dev_pm_opp_add(cpu_dev, opps->freq * 1000, opps->u_volt);
@@ -537,6 +543,8 @@ static struct clk *ve_spc_clk_register(struct device *cpu_dev)
         spc->hw.init = &init;
         spc->cluster = topology_physical_package_id(cpu_dev->id);
 
+        spc->cluster = spc->cluster < 0 ? 0 : spc->cluster;
+
         init.name = dev_name(cpu_dev);
         init.ops = &clk_spc_ops;
         init.flags = CLK_IS_ROOT | CLK_GET_RATE_NOCACHE;