arm64: avoid -Woverride-init warning

The icache_policy_str[] definition causes a warning when extra
warning flags are enabled:

arch/arm64/kernel/cpuinfo.c:38:26: warning: initialized field overwritten [-Woverride-init]
   38 |  [ICACHE_POLICY_VIPT]  = "VIPT",
      |                          ^~~~~~
arch/arm64/kernel/cpuinfo.c:38:26: note: (near initialization for 'icache_policy_str[2]')
arch/arm64/kernel/cpuinfo.c:39:26: warning: initialized field overwritten [-Woverride-init]
   39 |  [ICACHE_POLICY_PIPT]  = "PIPT",
      |                          ^~~~~~
arch/arm64/kernel/cpuinfo.c:39:26: note: (near initialization for 'icache_policy_str[3]')
arch/arm64/kernel/cpuinfo.c:40:27: warning: initialized field overwritten [-Woverride-init]
   40 |  [ICACHE_POLICY_VPIPT]  = "VPIPT",
      |                           ^~~~~~~
arch/arm64/kernel/cpuinfo.c:40:27: note: (near initialization for 'icache_policy_str[0]')

There is no real need for the default initializer here, as printing a
NULL string is harmless. Rewrite the logic to have an explicit
reserved value for the only one that uses the default value.

This partially reverts the commit that removed ICACHE_POLICY_AIVIVT.

Fixes: 155433cb365e ("arm64: cache: Remove support for ASID-tagged VIVT I-caches")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201026193807.3816388-1-arnd@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h
index 0ac3e06..63d43b5 100644 (file)
--- a/arch/arm64/include/asm/cache.h
+++ b/arch/arm64/include/asm/cache.h
@@ -24,6 +24,7 @@
 #define CTR_L1IP(ctr)          (((ctr) >> CTR_L1IP_SHIFT) & CTR_L1IP_MASK)
 
 #define ICACHE_POLICY_VPIPT    0
+#define ICACHE_POLICY_RESERVED 1
 #define ICACHE_POLICY_VIPT     2
 #define ICACHE_POLICY_PIPT     3
 

diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 6a7bb37..77605ae 100644 (file)
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -34,10 +34,10 @@ DEFINE_PER_CPU(struct cpuinfo_arm64, cpu_data);
 static struct cpuinfo_arm64 boot_cpu_data;
 
 static const char *icache_policy_str[] = {
-       [0 ... ICACHE_POLICY_PIPT]      = "RESERVED/UNKNOWN",
+       [ICACHE_POLICY_VPIPT]           = "VPIPT",
+       [ICACHE_POLICY_RESERVED]        = "RESERVED/UNKNOWN",
        [ICACHE_POLICY_VIPT]            = "VIPT",
        [ICACHE_POLICY_PIPT]            = "PIPT",
-       [ICACHE_POLICY_VPIPT]           = "VPIPT",
 };
 
 unsigned long __icache_flags;
@@ -334,10 +334,11 @@ static void cpuinfo_detect_icache_policy(struct cpuinfo_arm64 *info)
        case ICACHE_POLICY_VPIPT:
                set_bit(ICACHEF_VPIPT, &__icache_flags);
                break;
-       default:
+       case ICACHE_POLICY_RESERVED:
        case ICACHE_POLICY_VIPT:
                /* Assume aliasing */
                set_bit(ICACHEF_ALIASING, &__icache_flags);
+               break;
        }
 
        pr_info("Detected %s I-cache on CPU%d\n", icache_policy_str[l1ip], cpu);