arm64: mm: Remove unused support for Normal-WT memory type

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

Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210527110319.22157-4-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

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

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))
 

arch/arm64/include/asm/sysreg.h

@@ -704,7 +704,6 @@
 #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)

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