[PATCHv2 04/17] arm64: head.S: cleanup SCTLR_ELx initialization

Mark Rutland mark.rutland at arm.com
Tue Oct 6 10:46:29 EDT 2020


Let's make SCTLR_ELx initialization a bit clearer by using meaningful
names for the initialization values, following the same scheme for
SCTLR_EL1 and SCTLR_EL2.

These definitions will be used more widely in subsequent patches.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Christoph Hellwig <hch at lst.de>
Cc: James Morse <james.morse at arm.com>
Cc: Will Deacon <will at kernel.org>
---
 arch/arm64/include/asm/sysreg.h | 16 +++++++++++-----
 arch/arm64/kernel/head.S        |  6 +++---
 arch/arm64/mm/proc.S            |  2 +-
 3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index d436fe6d8bdf6..b6275efcc45f5 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -562,6 +562,9 @@
 #define ENDIAN_SET_EL2		0
 #endif
 
+#define INIT_SCTLR_EL2_MMU_OFF \
+	(SCTLR_EL2_RES1 | ENDIAN_SET_EL2)
+
 /* SCTLR_EL1 specific flags. */
 #define SCTLR_EL1_BT1		(BIT(36))
 #define SCTLR_EL1_BT0		(BIT(35))
@@ -587,11 +590,14 @@
 #define ENDIAN_SET_EL1		0
 #endif
 
-#define SCTLR_EL1_SET	(SCTLR_ELx_M    | SCTLR_ELx_C    | SCTLR_ELx_SA   |\
-			 SCTLR_EL1_SA0  | SCTLR_EL1_SED  | SCTLR_ELx_I    |\
-			 SCTLR_EL1_DZE  | SCTLR_EL1_UCT                   |\
-			 SCTLR_EL1_NTWE | SCTLR_ELx_IESB | SCTLR_EL1_SPAN |\
-			 ENDIAN_SET_EL1 | SCTLR_EL1_UCI  | SCTLR_EL1_RES1)
+#define INIT_SCTLR_EL1_MMU_OFF \
+	(ENDIAN_SET_EL1 | SCTLR_EL1_RES1)
+
+#define INIT_SCTLR_EL1_MMU_ON \
+	(SCTLR_ELx_M    | SCTLR_ELx_C    | SCTLR_ELx_SA   | SCTLR_EL1_SA0  | \
+	 SCTLR_EL1_SED  | SCTLR_ELx_I    | SCTLR_EL1_DZE  | SCTLR_EL1_UCT  | \
+	 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)
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index f367f2828d3d3..9bb07be45249a 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -498,13 +498,13 @@ SYM_FUNC_START(init_kernel_el)
 	mrs	x0, CurrentEL
 	cmp	x0, #CurrentEL_EL2
 	b.eq	1f
-	mov_q	x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1)
+	mov_q	x0, INIT_SCTLR_EL1_MMU_OFF
 	msr	sctlr_el1, x0
 	mov	w0, #BOOT_CPU_MODE_EL1		// This cpu booted in EL1
 	isb
 	ret
 
-1:	mov_q	x0, (SCTLR_EL2_RES1 | ENDIAN_SET_EL2)
+1:	mov_q	x0, INIT_SCTLR_EL2_MMU_OFF
 	msr	sctlr_el2, x0
 
 #ifdef CONFIG_ARM64_VHE
@@ -625,7 +625,7 @@ SYM_INNER_LABEL(install_el2_stub, SYM_L_LOCAL)
 	 * requires no configuration, and all non-hyp-specific EL2 setup
 	 * will be done via the _EL1 system register aliases in __cpu_setup.
 	 */
-	mov_q	x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1)
+	mov_q	x0, INIT_SCTLR_EL1_MMU_OFF
 	msr	sctlr_el1, x0
 
 	/* Coprocessor traps. */
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 796e47a571e66..a72a54246034b 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -461,6 +461,6 @@ SYM_FUNC_START(__cpu_setup)
 	/*
 	 * Prepare SCTLR
 	 */
-	mov_q	x0, SCTLR_EL1_SET
+	mov_q	x0, INIT_SCTLR_EL1_MMU_ON
 	ret					// return to head.S
 SYM_FUNC_END(__cpu_setup)
-- 
2.11.0




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