From 37479e65a353d6d5328092c092c8dc7dbcd4d001 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Pierre-Cl=C3=A9ment=20Tosi?= <ptosi@google.com>
Date: Fri, 27 Aug 2021 18:04:10 +0200
Subject: [PATCH] armv8/cache.S: Triple with single instruction
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Replace the current 2-instruction 2-step tripling code by a
corresponding single instruction leveraging ARMv8-A's "flexible second
operand as a register with optional shift". This has the added benefit
(albeit arguably negligible) of reducing the final code size.

Fix the comment as the tripled cache level is placed in x12, not x0.

Signed-off-by: Pierre-Clément Tosi <ptosi@google.com>
---
 arch/arm/cpu/armv8/cache.S | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/arm/cpu/armv8/cache.S b/arch/arm/cpu/armv8/cache.S
index eec2958107..d1cee23437 100644
--- a/arch/arm/cpu/armv8/cache.S
+++ b/arch/arm/cpu/armv8/cache.S
@@ -80,8 +80,7 @@ ENTRY(__asm_dcache_all)
 	/* x15 <- return address */
 
 loop_level:
-	lsl	x12, x0, #1
-	add	x12, x12, x0		/* x0 <- tripled cache level */
+	add	x12, x0, x0, lsl #1	/* x12 <- tripled cache level */
 	lsr	x12, x10, x12
 	and	x12, x12, #7		/* x12 <- cache type */
 	cmp	x12, #2
-- 
2.39.5