arm64: Use macros instead of hard-coded constants for MAIR_EL1

Currently, the arm64 __cpu_setup has hard-coded constants for the memory
attributes that go into the MAIR_EL1 register. Define proper macros in
asm/sysreg.h and make use of them in proc.S.

Signed-off-by: Catalin Marinas <[email protected]>
Signed-off-by: Will Deacon <[email protected]>

Author: ctmarinas

arch/arm64/include/asm/sysreg.h

@@ -538,6 +538,18 @@
 			 SCTLR_EL1_NTWE | SCTLR_ELx_IESB | SCTLR_EL1_SPAN |\
 			 ENDIAN_SET_EL1 | SCTLR_EL1_UCI  | SCTLR_EL1_RES1)
 
+/* MAIR_ELx memory attributes (used by Linux) */
+#define MAIR_ATTR_DEVICE_nGnRnE		UL(0x00)
+#define MAIR_ATTR_DEVICE_nGnRE		UL(0x04)
+#define MAIR_ATTR_DEVICE_GRE		UL(0x0c)
+#define MAIR_ATTR_NORMAL_NC		UL(0x44)
+#define MAIR_ATTR_NORMAL_WT		UL(0xbb)
+#define MAIR_ATTR_NORMAL		UL(0xff)
+#define MAIR_ATTR_MASK			UL(0xff)
+
+/* Position the attr at the correct index */
+#define MAIR_ATTRIDX(attr, idx)		((attr) << ((idx) * 8))
+
 /* id_aa64isar0 */
 #define ID_AA64ISAR0_TS_SHIFT		52
 #define ID_AA64ISAR0_FHM_SHIFT		48

arch/arm64/mm/proc.S

@@ -42,7 +42,14 @@
 #define TCR_KASAN_FLAGS 0
 #endif
 
-#define MAIR(attr, mt)	((attr) << ((mt) * 8))
+/* Default MAIR_EL1 */
+#define MAIR_EL1_SET							\
+	(MAIR_ATTRIDX(MAIR_ATTR_DEVICE_nGnRnE, MT_DEVICE_nGnRnE) |	\
+	 MAIR_ATTRIDX(MAIR_ATTR_DEVICE_nGnRE, MT_DEVICE_nGnRE) |	\
+	 MAIR_ATTRIDX(MAIR_ATTR_DEVICE_GRE, MT_DEVICE_GRE) |		\
+	 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))
 
 #ifdef CONFIG_CPU_PM
 /**
@@ -416,23 +423,9 @@ ENTRY(__cpu_setup)
 	enable_dbg				// since this is per-cpu
 	reset_pmuserenr_el0 x0			// Disable PMU access from EL0
 	/*
-	 * Memory region attributes for LPAE:
-	 *
-	 *   n = AttrIndx[2:0]
-	 *			n	MAIR
-	 *   DEVICE_nGnRnE	000	00000000
-	 *   DEVICE_nGnRE	001	00000100
-	 *   DEVICE_GRE		010	00001100
-	 *   NORMAL_NC		011	01000100
-	 *   NORMAL		100	11111111
-	 *   NORMAL_WT		101	10111011
+	 * Memory region attributes
 	 */
-	ldr	x5, =MAIR(0x00, MT_DEVICE_nGnRnE) | \
-		     MAIR(0x04, MT_DEVICE_nGnRE) | \
-		     MAIR(0x0c, MT_DEVICE_GRE) | \
-		     MAIR(0x44, MT_NORMAL_NC) | \
-		     MAIR(0xff, MT_NORMAL) | \
-		     MAIR(0xbb, MT_NORMAL_WT)
+	mov_q	x5, MAIR_EL1_SET
 	msr	mair_el1, x5
 	/*
 	 * Prepare SCTLR