[PATCH v10 12/18] arm64: kexec: arm64_relocate_new_kernel don't use x0 as temp

Pavel Tatashin pasha.tatashin at soleen.com
Mon Jan 25 14:19:17 EST 2021


x0 will contain the only argument to arm64_relocate_new_kernel; don't
use it as a temp. Reassigned registers to free-up x0 so we won't need
to copy argument, and can use it at the beginning and at the end of the
function.

Signed-off-by: Pavel Tatashin <pasha.tatashin at soleen.com>
Reviewed-by: James Morse <james.morse at arm.com>
---
 arch/arm64/kernel/relocate_kernel.S | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S
index 462ffbc37071..b78ea5de97a4 100644
--- a/arch/arm64/kernel/relocate_kernel.S
+++ b/arch/arm64/kernel/relocate_kernel.S
@@ -34,7 +34,7 @@ SYM_CODE_START(arm64_relocate_new_kernel)
 	mov	x13, xzr			/* x13 = copy dest */
 	/* Check if the new image needs relocation. */
 	tbnz	x16, IND_DONE_BIT, .Ldone
-	raw_dcache_line_size x15, x0		/* x15 = dcache line size */
+	raw_dcache_line_size x15, x1		/* x15 = dcache line size */
 .Lloop:
 	and	x12, x16, PAGE_MASK		/* x12 = addr */
 
@@ -43,17 +43,17 @@ SYM_CODE_START(arm64_relocate_new_kernel)
 	tbz	x16, IND_SOURCE_BIT, .Ltest_indirection
 
 	/* Invalidate dest page to PoC. */
-	mov     x0, x13
-	add     x20, x0, #PAGE_SIZE
+	mov     x2, x13
+	add     x20, x2, #PAGE_SIZE
 	sub     x1, x15, #1
-	bic     x0, x0, x1
-2:	dc      ivac, x0
-	add     x0, x0, x15
-	cmp     x0, x20
+	bic     x2, x2, x1
+2:	dc      ivac, x2
+	add     x2, x2, x15
+	cmp     x2, x20
 	b.lo    2b
 	dsb     sy
 
-	copy_page x13, x12, x0, x1, x2, x3, x4, x5, x6, x7
+	copy_page x13, x12, x1, x2, x3, x4, x5, x6, x7, x8
 	b	.Lnext
 .Ltest_indirection:
 	tbz	x16, IND_INDIRECTION_BIT, .Ltest_destination
-- 
2.25.1




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