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ARM: Use do_div() instead of division for "long long".

PATCH New Wolfgang Denk 2 participants 4 messages Oct 22, 2008 – Nov 2, 2008 Arm Samsung Exynos

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Wolfgang Denk

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#0 lore raw

PATCH 1/1 ARM: Use do_div() instead of division for "long long".

From: Sergei Poselenov <[email protected]>

Also make sure to feed the right compiler options.

Signed-off-by Sergei Poselenov <[email protected]>
Signed-off-by Wolfgang Denk <[email protected]>

---
These changes are needed with some more recent tool chain versions (including ELDK 4.2).

 board/integratorcp/integratorcp.c |    7 ++++++-
 board/trab/tsc2000.c              |   10 ++++++----
 cpu/arm1176/s3c64xx/interrupts.c  |    5 ++++-
 cpu/arm946es/config.mk            |    7 +++++++
 cpu/arm_intcm/config.mk           |    7 +++++++
 5 files changed, 30 insertions(+), 6 deletions(-)
board/integratorcp/integratorcp.c +6 -1
index d6d6e13..220513f 100644
@@ -34,6 +34,7 @@
  */
 
 #include <common.h>
+#include <div64.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 

@@ -244,7 +245,11 @@ ulong get_timer_masked (void)
 		total_count += lastdec - now;
 	}
 	lastdec	  = now;
-	timestamp = (ulong)(total_count/div_timer);
+
+	/* Reuse "now" */
+	now = total_count;
+	do_div(now, div_timer);
+	timestamp = now;
 
 	return timestamp;
 }
board/trab/tsc2000.c +6 -4
index 382a85b..f13a5a9 100644
@@ -27,6 +27,7 @@
 
 #include <common.h>
 #include <s3c2400.h>
+#include <div64.h>
 #include "tsc2000.h"
 
 #include "Pt1000_temp_data.h"

@@ -332,6 +333,7 @@ void tsc2000_reg_init (void)
 int tsc2000_interpolate(long value, long data[][2], long *result)
 {
 	int i;
+	unsigned long long val;
 
 	/* the data is sorted and the first element is upper
 	 * limit so we can easily check for out-of-band values

@@ -347,10 +349,10 @@ int tsc2000_interpolate(long value, long data[][2], long *result)
 	   result in 'long long'.
 	*/
 
-	*result = data[i-1][1] +
-		((unsigned long long)(data[i][1] - data[i-1][1])
-		 * (unsigned long long)(value - data[i-1][0]))
-		/ (data[i][0] - data[i-1][0]);
+	val = ((unsigned long long)(data[i][1] - data[i-1][1])
+		   * (unsigned long long)(value - data[i-1][0]));
+	do_div(val, (data[i][0] - data[i-1][0]));
+	*result = data[i-1][1] + val;
 
 	return 0;
 }
cpu/arm1176/s3c64xx/interrupts.c +4 -1
index 8356ae4..e34369f 100644
@@ -41,6 +41,7 @@
 #include <common.h>
 #include <asm/proc-armv/ptrace.h>
 #include <s3c6400.h>
+#include <div64.h>
 
 static ulong timer_load_val;
 

@@ -148,7 +149,9 @@ void reset_timer(void)
 
 ulong get_timer_masked(void)
 {
-	return get_ticks() / (timer_load_val / (100 * CFG_HZ));
+	unsigned long long res = get_ticks();
+	do_div (res, (timer_load_val / (100 * CFG_HZ)));
+	return res;
 }
 
 ulong get_timer(ulong base)
cpu/arm946es/config.mk +7 -0
index 81ca288..f774c7e 100644
@@ -25,3 +25,10 @@ PLATFORM_RELFLAGS += -fno-strict-aliasing  -fno-common -ffixed-r8 \
 	 -msoft-float
 
 PLATFORM_CPPFLAGS +=  -march=armv4
+# =========================================================================
+#
+# Supply options according to compiler version
+#
+# =========================================================================
+PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
+PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
cpu/arm_intcm/config.mk +7 -0
index 81ca288..f774c7e 100644
@@ -25,3 +25,10 @@ PLATFORM_RELFLAGS += -fno-strict-aliasing  -fno-common -ffixed-r8 \
 	 -msoft-float
 
 PLATFORM_CPPFLAGS +=  -march=armv4
+# =========================================================================
+#
+# Supply options according to compiler version
+#
+# =========================================================================
+PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu)
+PLATFORM_RELFLAGS +=$(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))
Signature · 1 line
1.5.5.1
#1 lore raw

PATCH 1/1 ARM: Use do_div() instead of division for "long long".

Quoted 7 lines

#include <asm/proc-armv/ptrace.h>
#include <s3c6400.h>

cpu/arm1176/s3c64xx/interrupts.c +1 -0
+#include <div64.h>
 
 static ulong timer_load_val;

cpu/arm1176/s3c64xx/interrupts.c void reset_timer(void) · line 154

Quoted 7 lines
cpu/arm1176/s3c64xx/interrupts.c +3 -1
@@ -148,7 +149,9 @@ void reset_timer(void)
 
 ulong get_timer_masked(void)
 {
-	return get_ticks() / (timer_load_val / (100 * CFG_HZ));
+	unsigned long long res = get_ticks();
+	do_div (res, (timer_load_val / (100 * CFG_HZ)));
+	return res;

CFG_HZ was renamed CONFIG_SYS_HZ

Review void reset_timer(void) · line 155

Quoted 1 line
(quoted diff) +0 -0
 }

I've start to think to re-rename it CFG_HZ as done in Linux, normaly this value is the same for all arch & board

Best Regards,
J.

author
#2 lore raw

PATCH 1/1 ARM: Use do_div() instead of division for "long long".

Dear Jean-Christophe PLAGNIOL-VILLARD,

Quoted 1 line · In message <[email protected]> you wrote:

...

Quoted 1 line

CFG_HZ was renamed CONFIG_SYS_HZ

...

Quoted 2 lines

I've start to think to re-rename it CFG_HZ as done in Linux, normaly this value is the same for all arch & board

Mind that there is a slight difference in meaning and a bigger one in implementation.

Best regards,

Wolfgang Denk

Signature · 5 lines
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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                                                   - David Ben Gurion
#3 lore raw

PATCH 1/1 ARM: Use do_div() instead of division for "long long".

In reply to Wolfgang Denk
Quoted 10 lines · Wolfgang Denk

From: Sergei Poselenov <[email protected]>

Also make sure to feed the right compiler options.

Signed-off-by Sergei Poselenov <[email protected]>
Signed-off-by Wolfgang Denk <[email protected]>

---
These changes are needed with some more recent tool chain versions (including ELDK 4.2).

Quoted 6 lines
 board/integratorcp/integratorcp.c |    7 ++++++-
 board/trab/tsc2000.c              |   10 ++++++----
 cpu/arm1176/s3c64xx/interrupts.c  |    5 ++++-
 cpu/arm946es/config.mk            |    7 +++++++
 cpu/arm_intcm/config.mk           |    7 +++++++
 5 files changed, 30 insertions(+), 6 deletions(-)

do you have any plan to rebase it?

Best Regards,
J.