Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
Hi, On Mon, Aug 24, 2015 at 04:31:13PM +0800, yalin wang wrote: > > i only submit the bit reverse patch for arm / arm64 arch, yes, saw later git blaming it on you :) > > Not for this case, but once measured on ARM, iirc, a 32-bit asm bit > > reversal as compared to doing it in C was taking 1 cycle as opposed to > > ~225 cycles!, of course writing optimized C could have made it fare > > better, but still would reach no-way near asm bit reversal. The above measurement was done not in Linux, rather on a baremetal code, but seeing the efficient Kernel C implementation, realized that the gain would not be that much, it would be good to know if there are measurements for Kernel bitreversal in C & asm (on supported arch) Regards afzal -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
> On Aug 22, 2015, at 15:53, Afzal Mohammed wrote: > > Hi, > > On Fri, Aug 21, 2015 at 11:01:41AM +0300, Tomi Valkeinen wrote: > Possibly the patches are still good for x86 also, but that needs to be proven. >>> not exactly, because x86_64 don’t have hardware instruction to do rbit OP, >>> i compile by test : >> >> For old drivers i386 may be more relevant than x86_64. > > It seems asm bit reversal is supported in Kernel on arm & arm64 only, > not sure whether any other arch even provide asm bit reversal > instruction. i only submit the bit reverse patch for arm / arm64 arch, i am not sure if there are some other arch also have hard ware bit reverse instructions, need arch maintainers to submit if their arch also have these hard ware instructions . :) > >> These kind of optimizations should have some real world measurements, > > Not for this case, but once measured on ARM, iirc, a 32-bit asm bit > reversal as compared to doing it in C was taking 1 cycle as opposed to > ~225 cycles!, of course writing optimized C could have made it fare > better, but still would reach no-way near asm bit reversal. > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
Hi, On Mon, Aug 24, 2015 at 04:31:13PM +0800, yalin wang wrote: i only submit the bit reverse patch for arm / arm64 arch, yes, saw later git blaming it on you :) Not for this case, but once measured on ARM, iirc, a 32-bit asm bit reversal as compared to doing it in C was taking 1 cycle as opposed to ~225 cycles!, of course writing optimized C could have made it fare better, but still would reach no-way near asm bit reversal. The above measurement was done not in Linux, rather on a baremetal code, but seeing the efficient Kernel C implementation, realized that the gain would not be that much, it would be good to know if there are measurements for Kernel bitreversal in C asm (on supported arch) Regards afzal -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On Aug 22, 2015, at 15:53, Afzal Mohammed afzal.mohd...@gmail.com wrote: Hi, On Fri, Aug 21, 2015 at 11:01:41AM +0300, Tomi Valkeinen wrote: Possibly the patches are still good for x86 also, but that needs to be proven. not exactly, because x86_64 don’t have hardware instruction to do rbit OP, i compile by test : For old drivers i386 may be more relevant than x86_64. It seems asm bit reversal is supported in Kernel on arm arm64 only, not sure whether any other arch even provide asm bit reversal instruction. i only submit the bit reverse patch for arm / arm64 arch, i am not sure if there are some other arch also have hard ware bit reverse instructions, need arch maintainers to submit if their arch also have these hard ware instructions . :) These kind of optimizations should have some real world measurements, Not for this case, but once measured on ARM, iirc, a 32-bit asm bit reversal as compared to doing it in C was taking 1 cycle as opposed to ~225 cycles!, of course writing optimized C could have made it fare better, but still would reach no-way near asm bit reversal. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
Hi, On Fri, Aug 21, 2015 at 11:01:41AM +0300, Tomi Valkeinen wrote: > >> Possibly the patches are still good for x86 also, but that needs to be > >> proven. > >> > > not exactly, because x86_64 don’t have hardware instruction to do rbit OP, > > i compile by test : > > For old drivers i386 may be more relevant than x86_64. It seems asm bit reversal is supported in Kernel on arm & arm64 only, not sure whether any other arch even provide asm bit reversal instruction. > These kind of optimizations should have some real world measurements, Not for this case, but once measured on ARM, iirc, a 32-bit asm bit reversal as compared to doing it in C was taking 1 cycle as opposed to ~225 cycles!, of course writing optimized C could have made it fare better, but still would reach no-way near asm bit reversal. Regards Afzal -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
Hi, On Fri, Aug 21, 2015 at 11:01:41AM +0300, Tomi Valkeinen wrote: Possibly the patches are still good for x86 also, but that needs to be proven. not exactly, because x86_64 don’t have hardware instruction to do rbit OP, i compile by test : For old drivers i386 may be more relevant than x86_64. It seems asm bit reversal is supported in Kernel on arm arm64 only, not sure whether any other arch even provide asm bit reversal instruction. These kind of optimizations should have some real world measurements, Not for this case, but once measured on ARM, iirc, a 32-bit asm bit reversal as compared to doing it in C was taking 1 cycle as opposed to ~225 cycles!, of course writing optimized C could have made it fare better, but still would reach no-way near asm bit reversal. Regards Afzal -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On 21/08/15 10:46, yalin wang wrote: >>> i investigate on arm64 platforms: >> >> Ok. So is any arm64 platform actually using these devices? If these >> devices are mostly used by 32bit x86 platforms, optimizing them for >> arm64 doesn't make any sense. >> >> Possibly the patches are still good for x86 also, but that needs to be >> proven. >> > not exactly, because x86_64 don’t have hardware instruction to do rbit OP, > i compile by test : For old drivers i386 may be more relevant than x86_64. So you don't have the actual HW? These kind of optimizations should have some real world measurements, not just compiling, looking at the assembly and guessing whether it's faster or not. Tomi signature.asc Description: OpenPGP digital signature
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
> On Aug 21, 2015, at 14:41, Tomi Valkeinen wrote:
>
>
>
> On 20/08/15 14:30, yalin wang wrote:
>>
>>> On Aug 20, 2015, at 19:02, Tomi Valkeinen wrote:
>>>
>>>
>>> On 10/08/15 13:12, yalin wang wrote:
This change to use swab32(bitrev32()) to implement reverse_order()
function, have better performance on some platforms.
>>>
>>> Which platforms? Presuming you tested this, roughly how much better
>>> performance? If you didn't, how do you know it's faster?
>>
>> i investigate on arm64 platforms:
>
> Ok. So is any arm64 platform actually using these devices? If these
> devices are mostly used by 32bit x86 platforms, optimizing them for
> arm64 doesn't make any sense.
>
> Possibly the patches are still good for x86 also, but that needs to be
> proven.
>
not exactly, because x86_64 don’t have hardware instruction to do rbit OP,
i compile by test :
use the patch:
use swab32(bitrev32()):
2775: 0f b6 d0movzbl %al,%edx
2778: 0f b6 c4movzbl %ah,%eax
277b: 0f b6 92 00 00 00 00movzbl 0x0(%rdx),%edx
2782: 0f b6 80 00 00 00 00movzbl 0x0(%rax),%eax
2789: c1 e2 08shl$0x8,%edx
278c: 09 d0 or %edx,%eax
278e: 0f b6 d5movzbl %ch,%edx
2791: 0f b6 c9movzbl %cl,%ecx
2794: 0f b6 89 00 00 00 00movzbl 0x0(%rcx),%ecx
279b: 0f b6 92 00 00 00 00movzbl 0x0(%rdx),%edx
27a2: 0f b7 c0movzwl %ax,%eax
27a5: c1 e1 08shl$0x8,%ecx
27a8: 09 ca or %ecx,%edx
27aa: c1 e2 10shl$0x10,%edx
27ad: 09 d0 or %edx,%eax
27af: 45 85 fftest %r15d,%r15d
27b2: 0f c8 bswap %eax
4 memory access instructions,
without the patch:
use
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)
277b: 45 0f b6 80 00 00 00movzbl 0x0(%r8),%r8d
2782: 00
2783: c1 ee 10shr$0x10,%esi
2786: 89 f2 mov%esi,%edx
2788: 0f b6 f4movzbl %ah,%esi
278b: c1 e8 18shr$0x18,%eax
278e: 0f b6 d2movzbl %dl,%edx
2791: 48 98 cltq
2793: 45 85 edtest %r13d,%r13d
2796: 0f b6 92 00 00 00 00movzbl 0x0(%rdx),%edx
279d: 0f b6 80 00 00 00 00movzbl 0x0(%rax),%eax
27a4: 44 88 85 54 ff ff ffmov%r8b,-0xac(%rbp)
27ab: 44 0f b6 86 00 00 00movzbl 0x0(%rsi),%r8d
27b2: 00
27b3: 88 95 56 ff ff ff mov%dl,-0xaa(%rbp)
27b9: 88 85 57 ff ff ff mov%al,-0xa9(%rbp)
27bf: 44 88 85 55 ff ff ffmov%r8b,-0xab(%rbp)
6 memory access instructions, and generate more code that the patch .
because the original code use byte access 4 times , i don’t
think have better performance. :)
Thanks
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Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On 20/08/15 14:30, yalin wang wrote: > >> On Aug 20, 2015, at 19:02, Tomi Valkeinen wrote: >> >> >> On 10/08/15 13:12, yalin wang wrote: >>> This change to use swab32(bitrev32()) to implement reverse_order() >>> function, have better performance on some platforms. >> >> Which platforms? Presuming you tested this, roughly how much better >> performance? If you didn't, how do you know it's faster? > > i investigate on arm64 platforms: Ok. So is any arm64 platform actually using these devices? If these devices are mostly used by 32bit x86 platforms, optimizing them for arm64 doesn't make any sense. Possibly the patches are still good for x86 also, but that needs to be proven. Tomi signature.asc Description: OpenPGP digital signature
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On 20/08/15 14:30, yalin wang wrote: On Aug 20, 2015, at 19:02, Tomi Valkeinen tomi.valkei...@ti.com wrote: On 10/08/15 13:12, yalin wang wrote: This change to use swab32(bitrev32()) to implement reverse_order() function, have better performance on some platforms. Which platforms? Presuming you tested this, roughly how much better performance? If you didn't, how do you know it's faster? i investigate on arm64 platforms: Ok. So is any arm64 platform actually using these devices? If these devices are mostly used by 32bit x86 platforms, optimizing them for arm64 doesn't make any sense. Possibly the patches are still good for x86 also, but that needs to be proven. Tomi signature.asc Description: OpenPGP digital signature
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On Aug 21, 2015, at 14:41, Tomi Valkeinen tomi.valkei...@ti.com wrote:
On 20/08/15 14:30, yalin wang wrote:
On Aug 20, 2015, at 19:02, Tomi Valkeinen tomi.valkei...@ti.com wrote:
On 10/08/15 13:12, yalin wang wrote:
This change to use swab32(bitrev32()) to implement reverse_order()
function, have better performance on some platforms.
Which platforms? Presuming you tested this, roughly how much better
performance? If you didn't, how do you know it's faster?
i investigate on arm64 platforms:
Ok. So is any arm64 platform actually using these devices? If these
devices are mostly used by 32bit x86 platforms, optimizing them for
arm64 doesn't make any sense.
Possibly the patches are still good for x86 also, but that needs to be
proven.
not exactly, because x86_64 don’t have hardware instruction to do rbit OP,
i compile by test :
use the patch:
use swab32(bitrev32()):
2775: 0f b6 d0movzbl %al,%edx
2778: 0f b6 c4movzbl %ah,%eax
277b: 0f b6 92 00 00 00 00movzbl 0x0(%rdx),%edx
2782: 0f b6 80 00 00 00 00movzbl 0x0(%rax),%eax
2789: c1 e2 08shl$0x8,%edx
278c: 09 d0 or %edx,%eax
278e: 0f b6 d5movzbl %ch,%edx
2791: 0f b6 c9movzbl %cl,%ecx
2794: 0f b6 89 00 00 00 00movzbl 0x0(%rcx),%ecx
279b: 0f b6 92 00 00 00 00movzbl 0x0(%rdx),%edx
27a2: 0f b7 c0movzwl %ax,%eax
27a5: c1 e1 08shl$0x8,%ecx
27a8: 09 ca or %ecx,%edx
27aa: c1 e2 10shl$0x10,%edx
27ad: 09 d0 or %edx,%eax
27af: 45 85 fftest %r15d,%r15d
27b2: 0f c8 bswap %eax
4 memory access instructions,
without the patch:
use
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)
277b: 45 0f b6 80 00 00 00movzbl 0x0(%r8),%r8d
2782: 00
2783: c1 ee 10shr$0x10,%esi
2786: 89 f2 mov%esi,%edx
2788: 0f b6 f4movzbl %ah,%esi
278b: c1 e8 18shr$0x18,%eax
278e: 0f b6 d2movzbl %dl,%edx
2791: 48 98 cltq
2793: 45 85 edtest %r13d,%r13d
2796: 0f b6 92 00 00 00 00movzbl 0x0(%rdx),%edx
279d: 0f b6 80 00 00 00 00movzbl 0x0(%rax),%eax
27a4: 44 88 85 54 ff ff ffmov%r8b,-0xac(%rbp)
27ab: 44 0f b6 86 00 00 00movzbl 0x0(%rsi),%r8d
27b2: 00
27b3: 88 95 56 ff ff ff mov%dl,-0xaa(%rbp)
27b9: 88 85 57 ff ff ff mov%al,-0xa9(%rbp)
27bf: 44 88 85 55 ff ff ffmov%r8b,-0xab(%rbp)
6 memory access instructions, and generate more code that the patch .
because the original code use byte access 4 times , i don’t
think have better performance. :)
Thanks
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Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On 21/08/15 10:46, yalin wang wrote: i investigate on arm64 platforms: Ok. So is any arm64 platform actually using these devices? If these devices are mostly used by 32bit x86 platforms, optimizing them for arm64 doesn't make any sense. Possibly the patches are still good for x86 also, but that needs to be proven. not exactly, because x86_64 don’t have hardware instruction to do rbit OP, i compile by test : For old drivers i386 may be more relevant than x86_64. So you don't have the actual HW? These kind of optimizations should have some real world measurements, not just compiling, looking at the assembly and guessing whether it's faster or not. Tomi signature.asc Description: OpenPGP digital signature
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
> On Aug 20, 2015, at 19:02, Tomi Valkeinen wrote:
>
>
> On 10/08/15 13:12, yalin wang wrote:
>> This change to use swab32(bitrev32()) to implement reverse_order()
>> function, have better performance on some platforms.
>
> Which platforms? Presuming you tested this, roughly how much better
> performance? If you didn't, how do you know it's faster?
i investigate on arm64 platforms:
for (j = dsize; j--;) {
tmp = data[k++];
tmp = reverse_order(tmp);
NVDmaNext(par, tmp);
bac: 110006a4add w4, w21, #0x1
bb0: 5ac000a3rbitw3, w5
if (dsize) {
NVDmaStart(info, par, RECT_EXPAND_TWO_COLOR_DATA(0), dsize);
for (j = dsize; j--;) {
tmp = data[k++];
bb4: 110006d6add w22, w22, #0x1
bb8: 5ac00861rev w1, w3
tmp = reverse_order(tmp);
NVDmaNext(par, tmp);
bbc: b9041e64str w4, [x19,#1052]
bc0: 8b3548c2add x2, x6, w21, uxtw #2
bc4: b941str w1, [x2]
this is the disassemble code after apply the patch,
only need:
rbitw3, w5
rev w1, w3
2 instruction to get the reverse_order() result,
apparently after than the origianl macro code.
>
>> Signed-off-by: yalin wang
>> ---
>> drivers/video/fbdev/riva/fbdev.c | 19 ++-
>> 1 file changed, 6 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/video/fbdev/riva/fbdev.c
>> b/drivers/video/fbdev/riva/fbdev.c
>> index f1ad274..4803901 100644
>> --- a/drivers/video/fbdev/riva/fbdev.c
>> +++ b/drivers/video/fbdev/riva/fbdev.c
>> @@ -40,6 +40,7 @@
>> #include
>> #include
>> #include
>> +#include
>> #include
>> #ifdef CONFIG_PMAC_BACKLIGHT
>> #include
>> @@ -84,6 +85,7 @@
>> #define SetBit(n)(1<<(n))
>> #define Set8Bits(value) ((value)&0xff)
>>
>> +#define reverse_order(v) swab32(bitrev32(v))
>> /* HW cursor parameters */
>> #define MAX_CURS 32
>>
>> @@ -451,15 +453,6 @@ static inline unsigned char MISCin(struct riva_par *par)
>> return (VGA_RD08(par->riva.PVIO, 0x3cc));
>> }
>>
>> -static inline void reverse_order(u32 *l)
>
> I would suggest to do the work in the inline function, instead of a
> macro. And if you keep the function prototype the same, then the changes
> to each reverse_order call site are not needed.
>
ok, i will change to a inline function.
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Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On 10/08/15 13:12, yalin wang wrote: > This change to use swab32(bitrev32()) to implement reverse_order() > function, have better performance on some platforms. Which platforms? Presuming you tested this, roughly how much better performance? If you didn't, how do you know it's faster? > Signed-off-by: yalin wang > --- > drivers/video/fbdev/riva/fbdev.c | 19 ++- > 1 file changed, 6 insertions(+), 13 deletions(-) > > diff --git a/drivers/video/fbdev/riva/fbdev.c > b/drivers/video/fbdev/riva/fbdev.c > index f1ad274..4803901 100644 > --- a/drivers/video/fbdev/riva/fbdev.c > +++ b/drivers/video/fbdev/riva/fbdev.c > @@ -40,6 +40,7 @@ > #include > #include > #include > +#include > #include > #ifdef CONFIG_PMAC_BACKLIGHT > #include > @@ -84,6 +85,7 @@ > #define SetBit(n)(1<<(n)) > #define Set8Bits(value) ((value)&0xff) > > +#define reverse_order(v) swab32(bitrev32(v)) > /* HW cursor parameters */ > #define MAX_CURS 32 > > @@ -451,15 +453,6 @@ static inline unsigned char MISCin(struct riva_par *par) > return (VGA_RD08(par->riva.PVIO, 0x3cc)); > } > > -static inline void reverse_order(u32 *l) I would suggest to do the work in the inline function, instead of a macro. And if you keep the function prototype the same, then the changes to each reverse_order call site are not needed. Tomi signature.asc Description: OpenPGP digital signature
Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On Aug 20, 2015, at 19:02, Tomi Valkeinen tomi.valkei...@ti.com wrote:
On 10/08/15 13:12, yalin wang wrote:
This change to use swab32(bitrev32()) to implement reverse_order()
function, have better performance on some platforms.
Which platforms? Presuming you tested this, roughly how much better
performance? If you didn't, how do you know it's faster?
i investigate on arm64 platforms:
for (j = dsize; j--;) {
tmp = data[k++];
tmp = reverse_order(tmp);
NVDmaNext(par, tmp);
bac: 110006a4add w4, w21, #0x1
bb0: 5ac000a3rbitw3, w5
if (dsize) {
NVDmaStart(info, par, RECT_EXPAND_TWO_COLOR_DATA(0), dsize);
for (j = dsize; j--;) {
tmp = data[k++];
bb4: 110006d6add w22, w22, #0x1
bb8: 5ac00861rev w1, w3
tmp = reverse_order(tmp);
NVDmaNext(par, tmp);
bbc: b9041e64str w4, [x19,#1052]
bc0: 8b3548c2add x2, x6, w21, uxtw #2
bc4: b941str w1, [x2]
this is the disassemble code after apply the patch,
only need:
rbitw3, w5
rev w1, w3
2 instruction to get the reverse_order() result,
apparently after than the origianl macro code.
Signed-off-by: yalin wang yalin.wang2...@gmail.com
---
drivers/video/fbdev/riva/fbdev.c | 19 ++-
1 file changed, 6 insertions(+), 13 deletions(-)
diff --git a/drivers/video/fbdev/riva/fbdev.c
b/drivers/video/fbdev/riva/fbdev.c
index f1ad274..4803901 100644
--- a/drivers/video/fbdev/riva/fbdev.c
+++ b/drivers/video/fbdev/riva/fbdev.c
@@ -40,6 +40,7 @@
#include linux/init.h
#include linux/pci.h
#include linux/backlight.h
+#include linux/swab.h
#include linux/bitrev.h
#ifdef CONFIG_PMAC_BACKLIGHT
#include asm/machdep.h
@@ -84,6 +85,7 @@
#define SetBit(n)(1(n))
#define Set8Bits(value) ((value)0xff)
+#define reverse_order(v) swab32(bitrev32(v))
/* HW cursor parameters */
#define MAX_CURS 32
@@ -451,15 +453,6 @@ static inline unsigned char MISCin(struct riva_par *par)
return (VGA_RD08(par-riva.PVIO, 0x3cc));
}
-static inline void reverse_order(u32 *l)
I would suggest to do the work in the inline function, instead of a
macro. And if you keep the function prototype the same, then the changes
to each reverse_order call site are not needed.
ok, i will change to a inline function.
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Re: [RFC] fbdev/riva:change to use generice function to implement reverse_order()
On 10/08/15 13:12, yalin wang wrote: This change to use swab32(bitrev32()) to implement reverse_order() function, have better performance on some platforms. Which platforms? Presuming you tested this, roughly how much better performance? If you didn't, how do you know it's faster? Signed-off-by: yalin wang yalin.wang2...@gmail.com --- drivers/video/fbdev/riva/fbdev.c | 19 ++- 1 file changed, 6 insertions(+), 13 deletions(-) diff --git a/drivers/video/fbdev/riva/fbdev.c b/drivers/video/fbdev/riva/fbdev.c index f1ad274..4803901 100644 --- a/drivers/video/fbdev/riva/fbdev.c +++ b/drivers/video/fbdev/riva/fbdev.c @@ -40,6 +40,7 @@ #include linux/init.h #include linux/pci.h #include linux/backlight.h +#include linux/swab.h #include linux/bitrev.h #ifdef CONFIG_PMAC_BACKLIGHT #include asm/machdep.h @@ -84,6 +85,7 @@ #define SetBit(n)(1(n)) #define Set8Bits(value) ((value)0xff) +#define reverse_order(v) swab32(bitrev32(v)) /* HW cursor parameters */ #define MAX_CURS 32 @@ -451,15 +453,6 @@ static inline unsigned char MISCin(struct riva_par *par) return (VGA_RD08(par-riva.PVIO, 0x3cc)); } -static inline void reverse_order(u32 *l) I would suggest to do the work in the inline function, instead of a macro. And if you keep the function prototype the same, then the changes to each reverse_order call site are not needed. Tomi signature.asc Description: OpenPGP digital signature
