[U-Boot] [PATCH 4/6] armv8/mmu: Set bits marked RES1 in TCR

Thierry Reding thierry.reding at gmail.com
Fri Mar 20 12:47:51 CET 2015


From: Thierry Reding <treding at nvidia.com>

For EL3 and EL2, the documentation says that bits 31 and 23 are reserved
but should be written as 1.

For EL1, only bit 23 is not reserved, so only write bit 31 as 1.

Cc: Albert Aribaud <albert.u.boot at aribaud.net>
Cc: Marc Zyngier <marc.zyngier at arm.com>
Signed-off-by: Thierry Reding <treding at nvidia.com>
---
 arch/arm/cpu/armv8/cache_v8.c    | 6 +++---
 arch/arm/include/asm/armv8/mmu.h | 4 ++++
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/arm/cpu/armv8/cache_v8.c b/arch/arm/cpu/armv8/cache_v8.c
index 254a629a3b8c..f9b04057f696 100644
--- a/arch/arm/cpu/armv8/cache_v8.c
+++ b/arch/arm/cpu/armv8/cache_v8.c
@@ -50,15 +50,15 @@ static void mmu_setup(void)
 	el = current_el();
 	if (el == 1) {
 		set_ttbr_tcr_mair(el, gd->arch.tlb_addr,
-				  TCR_FLAGS | TCR_EL1_IPS_BITS,
+				  TCR_EL1_RSVD | TCR_FLAGS | TCR_EL1_IPS_BITS,
 				  MEMORY_ATTRIBUTES);
 	} else if (el == 2) {
 		set_ttbr_tcr_mair(el, gd->arch.tlb_addr,
-				  TCR_FLAGS | TCR_EL2_IPS_BITS,
+				  TCR_EL2_RSVD | TCR_FLAGS | TCR_EL2_IPS_BITS,
 				  MEMORY_ATTRIBUTES);
 	} else {
 		set_ttbr_tcr_mair(el, gd->arch.tlb_addr,
-				  TCR_FLAGS | TCR_EL3_IPS_BITS,
+				  TCR_EL3_RSVD | TCR_FLAGS | TCR_EL3_IPS_BITS,
 				  MEMORY_ATTRIBUTES);
 	}
 	/* enable the mmu */
diff --git a/arch/arm/include/asm/armv8/mmu.h b/arch/arm/include/asm/armv8/mmu.h
index 6d42f5533a74..8e577b34e4ba 100644
--- a/arch/arm/include/asm/armv8/mmu.h
+++ b/arch/arm/include/asm/armv8/mmu.h
@@ -109,6 +109,10 @@
 				TCR_IRGN_WBWA |		\
 				TCR_T0SZ(VA_BITS))
 
+#define TCR_EL1_RSVD		(1 << 31)
+#define TCR_EL2_RSVD		(1 << 31 | 1 << 23)
+#define TCR_EL3_RSVD		(1 << 31 | 1 << 23)
+
 #ifndef __ASSEMBLY__
 void set_pgtable_section(u64 *page_table, u64 index,
 			 u64 section, u64 memory_type);
-- 
2.3.2



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