[PATCH 3/3] arm64: mm: Remove unused support for Normal-WT memory type

Will Deacon will at kernel.org
Thu May 6 02:50:34 PDT 2021


The Normal-WT memory type is unused, so remove it and reclaim a MAIR.

Cc: Christoph Hellwig <hch at lst.de>
Signed-off-by: Will Deacon <will at kernel.org>
---
 arch/arm64/include/asm/memory.h       | 5 ++---
 arch/arm64/include/asm/pgtable-prot.h | 1 -
 arch/arm64/include/asm/sysreg.h       | 1 -
 arch/arm64/mm/proc.S                  | 1 -
 4 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index ea268be37ea2..865fa2ab51b2 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -135,9 +135,8 @@
 #define MT_NORMAL		0
 #define MT_NORMAL_TAGGED	1
 #define MT_NORMAL_NC		2
-#define MT_NORMAL_WT		3
-#define MT_DEVICE_nGnRnE	4
-#define MT_DEVICE_nGnRE		5
+#define MT_DEVICE_nGnRnE	3
+#define MT_DEVICE_nGnRE		4
 
 /*
  * Memory types for Stage-2 translation
diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h
index fab2f573f7a4..8923c9b119ae 100644
--- a/arch/arm64/include/asm/pgtable-prot.h
+++ b/arch/arm64/include/asm/pgtable-prot.h
@@ -55,7 +55,6 @@ extern bool arm64_use_ng_mappings;
 #define PROT_DEVICE_nGnRnE	(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRnE))
 #define PROT_DEVICE_nGnRE	(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRE))
 #define PROT_NORMAL_NC		(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_NC))
-#define PROT_NORMAL_WT		(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_WT))
 #define PROT_NORMAL		(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL))
 #define PROT_NORMAL_TAGGED	(PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_TAGGED))
 
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index aa8e53dd8686..ec27455d2a44 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -652,7 +652,6 @@
 #define MAIR_ATTR_DEVICE_nGnRnE		UL(0x00)
 #define MAIR_ATTR_DEVICE_nGnRE		UL(0x04)
 #define MAIR_ATTR_NORMAL_NC		UL(0x44)
-#define MAIR_ATTR_NORMAL_WT		UL(0xbb)
 #define MAIR_ATTR_NORMAL_TAGGED		UL(0xf0)
 #define MAIR_ATTR_NORMAL		UL(0xff)
 #define MAIR_ATTR_MASK			UL(0xff)
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index be6e5d1e3673..c2d57eb0e671 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -60,7 +60,6 @@
 	 MAIR_ATTRIDX(MAIR_ATTR_DEVICE_nGnRE, MT_DEVICE_nGnRE) |	\
 	 MAIR_ATTRIDX(MAIR_ATTR_NORMAL_NC, MT_NORMAL_NC) |		\
 	 MAIR_ATTRIDX(MAIR_ATTR_NORMAL, MT_NORMAL) |			\
-	 MAIR_ATTRIDX(MAIR_ATTR_NORMAL_WT, MT_NORMAL_WT) |		\
 	 MAIR_ATTRIDX(MAIR_ATTR_NORMAL, MT_NORMAL_TAGGED))
 
 #ifdef CONFIG_CPU_PM
-- 
2.31.1.607.g51e8a6a459-goog




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