1. make sure that page table setup is not done multiple times
2. flush_dcache_all() is more appropriate while disabling cache
   than a range flush on the entire memory(flush_cache())

   Provide a default implementation for flush_dcache_all()
   for backward compatibility and to avoid build issues.

Signed-off-by: Aneesh V <ane...@ti.com>
---
 arch/arm/lib/cache-cp15.c |    9 +++++++--
 arch/arm/lib/cache.c      |   11 +++++++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/arch/arm/lib/cache-cp15.c b/arch/arm/lib/cache-cp15.c
index fd97c45..b1ccc3c 100644
--- a/arch/arm/lib/cache-cp15.c
+++ b/arch/arm/lib/cache-cp15.c
@@ -92,13 +92,18 @@ static inline void mmu_setup(void)
        set_cr(reg | CR_M);
 }
 
+static int mmu_enabled(void)
+{
+       return get_cr() & CR_M;
+}
+
 /* cache_bit must be either CR_I or CR_C */
 static void cache_enable(uint32_t cache_bit)
 {
        uint32_t reg;
 
        /* The data cache is not active unless the mmu is enabled too */
-       if (cache_bit == CR_C)
+       if ((cache_bit == CR_C) && !mmu_enabled())
                mmu_setup();
        reg = get_cr(); /* get control reg. */
        cp_delay();
@@ -117,7 +122,7 @@ static void cache_disable(uint32_t cache_bit)
                        return;
                /* if disabling data cache, disable mmu too */
                cache_bit |= CR_M;
-               flush_cache(0, ~0);
+               flush_dcache_all();
        }
        reg = get_cr();
        cp_delay();
diff --git a/arch/arm/lib/cache.c b/arch/arm/lib/cache.c
index dc3242c..92b61a2 100644
--- a/arch/arm/lib/cache.c
+++ b/arch/arm/lib/cache.c
@@ -42,3 +42,14 @@ void  __flush_cache(unsigned long start, unsigned long size)
 }
 void  flush_cache(unsigned long start, unsigned long size)
        __attribute__((weak, alias("__flush_cache")));
+
+/*
+ * Default implementation:
+ * do a range flush for the entire range
+ */
+void   __flush_dcache_all(void)
+{
+       flush_cache(0, ~0);
+}
+void   flush_dcache_all(void)
+       __attribute__((weak, alias("__flush_dcache_all")));
-- 
1.7.0.4

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