From: Patrice Chotard patrice.chotard@foss.st.com
At early U-Boot stage, before relocation, MMU is not yet configured and disabled. DDR may not be configured with the correct memory attributes (can be configured in MT_DEVICE instead of MT_MEMORY).
In this case, usage of memcpy_{from, to}io() may leads to synchronous abort in AARCH64 in case the normal memory address is not 64Bits aligned.
To avoid such situation, forbid usage of normal memory cast to (u64 *) in case MMU is not enabled.
Signed-off-by: Patrice Chotard patrice.chotard@foss.st.com Reviewed-by: Patrick Delaunay patrick.delaunay@foss.st.com Cc: mark.kettenis@xs4all.nl Signed-off-by: Patrick Delaunay patrick.delaunay@foss.st.com ---
(no changes since v1)
arch/arm/cpu/armv8/cache_v8.c | 10 ++++++++++ arch/arm/include/asm/io.h | 25 +++++++++++++++---------- include/cpu_func.h | 1 + 3 files changed, 26 insertions(+), 10 deletions(-)
diff --git a/arch/arm/cpu/armv8/cache_v8.c b/arch/arm/cpu/armv8/cache_v8.c index 15cecb5e0b..3de18c7675 100644 --- a/arch/arm/cpu/armv8/cache_v8.c +++ b/arch/arm/cpu/armv8/cache_v8.c @@ -719,6 +719,11 @@ int icache_status(void) return (get_sctlr() & CR_I) != 0; }
+int mmu_status(void) +{ + return (get_sctlr() & CR_M) != 0; +} + void invalidate_icache_all(void) { __asm_invalidate_icache_all(); @@ -740,6 +745,11 @@ int icache_status(void) return 0; }
+int mmu_status(void) +{ + return 0; +} + void invalidate_icache_all(void) { } diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h index df264a170b..36b840378a 100644 --- a/arch/arm/include/asm/io.h +++ b/arch/arm/include/asm/io.h @@ -338,6 +338,7 @@ extern void __readwrite_bug(const char *fn);
/* Optimized copy functions to read from/write to IO sapce */ #ifdef CONFIG_ARM64 +#include <cpu_func.h> /* * Copy data from IO memory space to "real" memory space. */ @@ -351,11 +352,13 @@ void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count) count--; }
- while (count >= 8) { - *(u64 *)to = __raw_readq(from); - from += 8; - to += 8; - count -= 8; + if (mmu_status()) { + while (count >= 8) { + *(u64 *)to = __raw_readq(from); + from += 8; + to += 8; + count -= 8; + } }
while (count) { @@ -379,11 +382,13 @@ void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count) count--; }
- while (count >= 8) { - __raw_writeq(*(u64 *)from, to); - from += 8; - to += 8; - count -= 8; + if (mmu_status()) { + while (count >= 8) { + __raw_writeq(*(u64 *)from, to); + from += 8; + to += 8; + count -= 8; + } }
while (count) { diff --git a/include/cpu_func.h b/include/cpu_func.h index c3a66f0405..23cd5eca39 100644 --- a/include/cpu_func.h +++ b/include/cpu_func.h @@ -59,6 +59,7 @@ int dcache_status(void); void dcache_enable(void); void dcache_disable(void); void mmu_disable(void); +int mmu_status(void);
/* arch/$(ARCH)/lib/cache.c */ void enable_caches(void);