Module Name: src
Committed By: ryo
Date: Tue Aug 23 05:29:44 UTC 2022
Modified Files:
src/sys/arch/aarch64/aarch64: start.S
Log Message:
Align the loaded kernel image to 2Mbytes, if necessary.
It appears that there are bootloaders that cannot specify the load address or
ignore it.
To generate a diff of this commit:
cvs rdiff -u -r1.11 -r1.12 src/sys/arch/aarch64/aarch64/start.S
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/aarch64/aarch64/start.S
diff -u src/sys/arch/aarch64/aarch64/start.S:1.11 src/sys/arch/aarch64/aarch64/start.S:1.12
--- src/sys/arch/aarch64/aarch64/start.S:1.11 Tue Sep 15 09:28:20 2020
+++ src/sys/arch/aarch64/aarch64/start.S Tue Aug 23 05:29:44 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: start.S,v 1.11 2020/09/15 09:28:20 ryo Exp $ */
+/* $NetBSD: start.S,v 1.12 2022/08/23 05:29:44 ryo Exp $ */
/*
* Copyright (c) 2017 Ryo Shimizu <r...@nerv.org>
@@ -33,12 +33,13 @@
#include <aarch64/asm.h>
#include "assym.h"
-RCSID("$NetBSD: start.S,v 1.11 2020/09/15 09:28:20 ryo Exp $")
+RCSID("$NetBSD: start.S,v 1.12 2022/08/23 05:29:44 ryo Exp $")
/*
* Padding at start of kernel image to make room for 64-byte header
* (non-ELF booting)
*/
+.header:
.space 64, 0x0
/*
@@ -46,6 +47,40 @@ RCSID("$NetBSD: start.S,v 1.11 2020/09/1
*/
.global start
start:
+ /* DON'T CLOBBER X0-X3 REGISTERS. THEY ARE UBOOT ARGUMENTS */
+
+ /*
+ * Relocate to L2_SIZE(2Mbyte) align if necessary
+ *
+ * x8 = currently loaded address
+ * x9 = (x8 + L2_SIZE - 1) & -L2_SIZE = new (aligned) loaded address
+ */
+ adrl x8, .header
+ mov x9, #(L2_SIZE-1)
+ add x9, x9, x8
+ and x9, x9, #-L2_SIZE
+ cmp x8, x9
+ b.eq 9f
+
+ /* x10 = size = (_edata - __kernel_text) */
+ adrl x10, _edata
+ adrl x11, __kernel_text
+ sub x10, x10, x11
+
+ /* do memmove(x9, x8, x10) */
+ add x8, x8, x10
+ add x13, x9, x10
+1:
+ ldp x11, x12, [x8, #-16]!
+ stp x11, x12, [x13, #-16]!
+ cmp x13, x9
+ b.hi 1b
+
+ /* jump to new (aligned) loaded address */
+ add x9, x9, #(start - .header) /* skip header */
+ br x9
+9:
+
mrs x8, CurrentEL
lsr x8, x8, #2
cmp x8, #0x2
