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-rw-r--r--arch/powerpc/boot/util.S41
1 files changed, 10 insertions, 31 deletions
diff --git a/arch/powerpc/boot/util.S b/arch/powerpc/boot/util.S
index 427ddfc11991..6a92376daf3f 100644
--- a/arch/powerpc/boot/util.S
+++ b/arch/powerpc/boot/util.S
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copied from <file:arch/powerpc/kernel/misc_32.S>
*
@@ -10,12 +11,6 @@
* kexec bits:
* Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com>
* GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- *
*/
#include "ppc_asm.h"
@@ -23,7 +18,7 @@
.text
-/* udelay (on non-601 processors) needs to know the period of the
+/* udelay needs to know the period of the
* timebase in nanoseconds. This used to be hardcoded to be 60ns
* (period of 66MHz/4). Now a variable is used that is initialized to
* 60 for backward compatibility, but it can be overridden as necessary
@@ -42,47 +37,31 @@ timebase_period_ns:
*/
.globl udelay
udelay:
- mfspr r4,SPRN_PVR
- srwi r4,r4,16
- cmpwi 0,r4,1 /* 601 ? */
- bne .udelay_not_601
-00: li r0,86 /* Instructions / microsecond? */
- mtctr r0
-10: addi r0,r0,0 /* NOP */
- bdnz 10b
- subic. r3,r3,1
- bne 00b
- blr
-
-.udelay_not_601:
mulli r4,r3,1000 /* nanoseconds */
/* Change r4 to be the number of ticks using:
* (nanoseconds + (timebase_period_ns - 1 )) / timebase_period_ns
* timebase_period_ns defaults to 60 (16.6MHz) */
mflr r5
- bl 0f
+ bcl 20,31,0f
0: mflr r6
mtlr r5
- lis r5,0b@ha
- addi r5,r5,0b@l
- subf r5,r5,r6 /* In case we're relocated */
- addis r5,r5,timebase_period_ns@ha
- lwz r5,timebase_period_ns@l(r5)
+ addis r5,r6,(timebase_period_ns-0b)@ha
+ lwz r5,(timebase_period_ns-0b)@l(r5)
add r4,r4,r5
addi r4,r4,-1
divw r4,r4,r5 /* BUS ticks */
-1: mftbu r5
- mftb r6
- mftbu r7
+1: MFTBU(r5)
+ MFTBL(r6)
+ MFTBU(r7)
cmpw 0,r5,r7
bne 1b /* Get [synced] base time */
addc r9,r6,r4 /* Compute end time */
addze r8,r5
-2: mftbu r5
+2: MFTBU(r5)
cmpw 0,r5,r8
blt 2b
bgt 3f
- mftb r6
+ MFTBL(r6)
cmpw 0,r6,r9
blt 2b
3: blr