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-rw-r--r--arch/arm/lib/Makefile2
-rw-r--r--arch/arm/lib/delay-loop.S (renamed from arch/arm/lib/delay.S)20
-rw-r--r--arch/arm/lib/delay.c71
3 files changed, 81 insertions, 12 deletions
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index d5060dab6e52..2473fd1fd51c 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -6,7 +6,7 @@
lib-y := backtrace.o changebit.o csumipv6.o csumpartial.o \
csumpartialcopy.o csumpartialcopyuser.o clearbit.o \
- delay.o findbit.o memchr.o memcpy.o \
+ delay.o delay-loop.o findbit.o memchr.o memcpy.o \
memmove.o memset.o memzero.o setbit.o \
strchr.o strrchr.o \
testchangebit.o testclearbit.o testsetbit.o \
diff --git a/arch/arm/lib/delay.S b/arch/arm/lib/delay-loop.S
index 3c9a05c8d20b..36b668d8e121 100644
--- a/arch/arm/lib/delay.S
+++ b/arch/arm/lib/delay-loop.S
@@ -9,11 +9,11 @@
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
-#include <asm/param.h>
+#include <asm/delay.h>
.text
.LC0: .word loops_per_jiffy
-.LC1: .word (2199023*HZ)>>11
+.LC1: .word UDELAY_MULT
/*
* r0 <= 2000
@@ -21,10 +21,10 @@
* HZ <= 1000
*/
-ENTRY(__udelay)
+ENTRY(__loop_udelay)
ldr r2, .LC1
mul r0, r2, r0
-ENTRY(__const_udelay) @ 0 <= r0 <= 0x7fffff06
+ENTRY(__loop_const_udelay) @ 0 <= r0 <= 0x7fffff06
mov r1, #-1
ldr r2, .LC0
ldr r2, [r2] @ max = 0x01ffffff
@@ -39,12 +39,10 @@ ENTRY(__const_udelay) @ 0 <= r0 <= 0x7fffff06
/*
* loops = r0 * HZ * loops_per_jiffy / 1000000
- *
- * Oh, if only we had a cycle counter...
*/
@ Delay routine
-ENTRY(__delay)
+ENTRY(__loop_delay)
subs r0, r0, #1
#if 0
movls pc, lr
@@ -62,8 +60,8 @@ ENTRY(__delay)
movls pc, lr
subs r0, r0, #1
#endif
- bhi __delay
+ bhi __loop_delay
mov pc, lr
-ENDPROC(__udelay)
-ENDPROC(__const_udelay)
-ENDPROC(__delay)
+ENDPROC(__loop_udelay)
+ENDPROC(__loop_const_udelay)
+ENDPROC(__loop_delay)
diff --git a/arch/arm/lib/delay.c b/arch/arm/lib/delay.c
new file mode 100644
index 000000000000..d6dacc69254e
--- /dev/null
+++ b/arch/arm/lib/delay.c
@@ -0,0 +1,71 @@
+/*
+ * Delay loops based on the OpenRISC implementation.
+ *
+ * Copyright (C) 2012 ARM Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/timex.h>
+
+/*
+ * Default to the loop-based delay implementation.
+ */
+struct arm_delay_ops arm_delay_ops = {
+ .delay = __loop_delay,
+ .const_udelay = __loop_const_udelay,
+ .udelay = __loop_udelay,
+};
+
+#ifdef ARCH_HAS_READ_CURRENT_TIMER
+static void __timer_delay(unsigned long cycles)
+{
+ cycles_t start = get_cycles();
+
+ while ((get_cycles() - start) < cycles)
+ cpu_relax();
+}
+
+static void __timer_const_udelay(unsigned long xloops)
+{
+ unsigned long long loops = xloops;
+ loops *= loops_per_jiffy;
+ __timer_delay(loops >> UDELAY_SHIFT);
+}
+
+static void __timer_udelay(unsigned long usecs)
+{
+ __timer_const_udelay(usecs * UDELAY_MULT);
+}
+
+void __init init_current_timer_delay(unsigned long freq)
+{
+ pr_info("Switching to timer-based delay loop\n");
+ lpj_fine = freq / HZ;
+ arm_delay_ops.delay = __timer_delay;
+ arm_delay_ops.const_udelay = __timer_const_udelay;
+ arm_delay_ops.udelay = __timer_udelay;
+}
+
+unsigned long __cpuinit calibrate_delay_is_known(void)
+{
+ return lpj_fine;
+}
+#endif