[RFC] fbdev/nvidia:change reverse_order() macro

[RFC] fbdev/nvidia:change reverse_order() macro

[yalin wang]

This change reverse_order() to swab32(bitrev32()), so that
it can have better performance on some platforms.

Signed-off-by: yalin wang <yalin.wang2010@gmail.com>
---
 drivers/video/fbdev/nvidia/nv_accel.c |  4 ++--
 drivers/video/fbdev/nvidia/nv_local.h | 13 ++++---------
 2 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/drivers/video/fbdev/nvidia/nv_accel.c b/drivers/video/fbdev/nvidia/nv_accel.c
index ad6472a..c21cb34 100644
--- a/drivers/video/fbdev/nvidia/nv_accel.c
+++ b/drivers/video/fbdev/nvidia/nv_accel.c
@@ -382,7 +382,7 @@ static void nvidiafb_mono_color_expand(struct fb_info *info,
 
 		for (j = RECT_EXPAND_TWO_COLOR_DATA_MAX_DWORDS; j--;) {
 			tmp = data[k++];
-			reverse_order(&tmp);
+			tmp = reverse_order(tmp);
 			NVDmaNext(par, tmp);
 		}
 
@@ -394,7 +394,7 @@ static void nvidiafb_mono_color_expand(struct fb_info *info,
 
 		for (j = dsize; j--;) {
 			tmp = data[k++];
-			reverse_order(&tmp);
+			tmp = reverse_order(tmp);
 			NVDmaNext(par, tmp);
 		}
 	}
diff --git a/drivers/video/fbdev/nvidia/nv_local.h b/drivers/video/fbdev/nvidia/nv_local.h
index 68e508d..a0eb1f3 100644
--- a/drivers/video/fbdev/nvidia/nv_local.h
+++ b/drivers/video/fbdev/nvidia/nv_local.h
@@ -97,18 +97,13 @@
 
 #ifdef __LITTLE_ENDIAN
 
+#include <linux/swab.h>
 #include <linux/bitrev.h>
 
-#define reverse_order(l)        \
-do {                            \
-	u8 *a = (u8 *)(l);      \
-	a[0] = bitrev8(a[0]);   \
-	a[1] = bitrev8(a[1]);   \
-	a[2] = bitrev8(a[2]);   \
-	a[3] = bitrev8(a[3]);   \
-} while(0)
+#define reverse_order(v)	swab32(bitrev32(v))
+
 #else
-#define reverse_order(l) do { } while(0)
+#define reverse_order(v)	(v)
 #endif                          /* __LITTLE_ENDIAN */
 
 #endif				/* __NV_LOCAL_H__ */
-- 
1.9.1

Re: [RFC] fbdev/nvidia:change reverse_order() macro

[Tomi Valkeinen]

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On 20/08/15 09:52, yalin wang wrote:
> This change reverse_order() to swab32(bitrev32()), so that
> it can have better performance on some platforms.
> 
> Signed-off-by: yalin wang <yalin.wang2010@gmail.com>
> ---
>  drivers/video/fbdev/nvidia/nv_accel.c |  4 ++--
>  drivers/video/fbdev/nvidia/nv_local.h | 13 ++++---------
>  2 files changed, 6 insertions(+), 11 deletions(-)

I have more or less the same comments here as for the riva patch, except
in this one I'd change the macro to an static inline function.

 Tomi


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