[PATCH] ARM: Check for is_smp for tlb_ops and cache_ops boardcast

Tony Lindgren tony at atomide.com
Tue Sep 7 23:12:14 EDT 2010


This should not be needed when running on UP systems.

Additionally we will also get an undefined instruction on ARM cores
without the extended CPUID registers with CONFIG_SMP_ON_UP.

Also, we can now remove the is_smp() test from mmu.c.

Signed-off-by: Tony Lindgren <tony at atomide.com>

diff --git a/arch/arm/include/asm/smp_plat.h b/arch/arm/include/asm/smp_plat.h
index 7de5aa5..7f4e663 100644
--- a/arch/arm/include/asm/smp_plat.h
+++ b/arch/arm/include/asm/smp_plat.h
@@ -7,17 +7,6 @@
 
 #include <asm/cputype.h>
 
-/* all SMP configurations have the extended CPUID registers */
-static inline int tlb_ops_need_broadcast(void)
-{
-	return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
-}
-
-static inline int cache_ops_need_broadcast(void)
-{
-	return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
-}
-
 /*
  * Return true if we are running on a SMP platform
  */
@@ -33,4 +22,21 @@ static inline bool is_smp(void)
 #endif
 }
 
+/* all SMP configurations have the extended CPUID registers */
+static inline int tlb_ops_need_broadcast(void)
+{
+	if (!is_smp())
+		return 0;
+
+	return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
+}
+
+static inline int cache_ops_need_broadcast(void)
+{
+	if (!is_smp())
+		return 0;
+
+	return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
+}
+
 #endif
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index a789320..34df905 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -800,7 +800,7 @@ static void __init sanity_check_meminfo(void)
 			 * rather difficult.
 			 */
 			reason = "with VIPT aliasing cache";
-		} else if (is_smp() && tlb_ops_need_broadcast()) {
+		} else if (tlb_ops_need_broadcast()) {
 			/*
 			 * kmap_high needs to occasionally flush TLB entries,
 			 * however, if the TLB entries need to be broadcast



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