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-rw-r--r--arch/arm/lib/delay.S20
1 files changed, 12 insertions, 8 deletions
diff --git a/arch/arm/lib/delay.S b/arch/arm/lib/delay.S
index b3fb475b4120..9183b06c0e2f 100644
--- a/arch/arm/lib/delay.S
+++ b/arch/arm/lib/delay.S
@@ -9,28 +9,32 @@
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
+#include <asm/param.h>
.text
.LC0: .word loops_per_jiffy
+.LC1: .word (2199023*HZ)>>11
/*
- * 0 <= r0 <= 2000
+ * r0 <= 2000
+ * lpj <= 0x01ffffff (max. 3355 bogomips)
+ * HZ <= 1000
*/
+
ENTRY(__udelay)
- mov r2, #0x6800
- orr r2, r2, #0x00db
+ ldr r2, .LC1
mul r0, r2, r0
-ENTRY(__const_udelay) @ 0 <= r0 <= 0x01ffffff
+ENTRY(__const_udelay) @ 0 <= r0 <= 0x7fffff06
ldr r2, .LC0
- ldr r2, [r2] @ max = 0x0fffffff
- mov r0, r0, lsr #11 @ max = 0x00003fff
- mov r2, r2, lsr #11 @ max = 0x0003ffff
+ ldr r2, [r2] @ max = 0x01ffffff
+ mov r0, r0, lsr #14 @ max = 0x0001ffff
+ mov r2, r2, lsr #10 @ max = 0x00007fff
mul r0, r2, r0 @ max = 2^32-1
movs r0, r0, lsr #6
RETINSTR(moveq,pc,lr)
/*
- * loops = (r0 * 0x10c6 * 100 * loops_per_jiffy) / 2^32
+ * loops = r0 * HZ * loops_per_jiffy / 1000000
*
* Oh, if only we had a cycle counter...
*/