* [PATCH] carl9170: Convert byte_rev_table uses to bitrev8
@ 2014-11-14 5:16 Wang, Yalin
2014-11-14 5:32 ` Joe Perches
0 siblings, 1 reply; 4+ messages in thread
From: Wang, Yalin @ 2014-11-14 5:16 UTC (permalink / raw)
To: 'chunkeey@googlemail.com',
'linville@tuxdriver.com',
'linux-wireless@vger.kernel.org',
'netdev@vger.kernel.org',
'linux-kernel@vger.kernel.org', 'joe@perches.com'
Use the inline function instead of directly indexing the array.
This allows some architectures with hardware instructions for bit
reversals to eliminate the array.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
---
drivers/net/wireless/ath/carl9170/phy.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/ath/carl9170/phy.c b/drivers/net/wireless/ath/carl9170/phy.c
index b80b213..dca6df1 100644
--- a/drivers/net/wireless/ath/carl9170/phy.c
+++ b/drivers/net/wireless/ath/carl9170/phy.c
@@ -994,7 +994,7 @@ static int carl9170_init_rf_bank4_pwr(struct ar9170 *ar, bool band5ghz,
refsel0 = 0;
refsel1 = 1;
}
- chansel = byte_rev_table[chansel];
+ chansel = bitrev8(chansel);
} else {
if (freq == 2484) {
chansel = 10 + (freq - 2274) / 5;
@@ -1002,7 +1002,7 @@ static int carl9170_init_rf_bank4_pwr(struct ar9170 *ar, bool band5ghz,
} else
chansel = 16 + (freq - 2272) / 5;
chansel *= 4;
- chansel = byte_rev_table[chansel];
+ chansel = bitrev8(chansel);
}
d1 = chansel;
--
2.1.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH] carl9170: Convert byte_rev_table uses to bitrev8
2014-11-14 5:16 [PATCH] carl9170: Convert byte_rev_table uses to bitrev8 Wang, Yalin
@ 2014-11-14 5:32 ` Joe Perches
2014-11-14 5:37 ` Wang, Yalin
0 siblings, 1 reply; 4+ messages in thread
From: Joe Perches @ 2014-11-14 5:32 UTC (permalink / raw)
To: Wang, Yalin
Cc: 'chunkeey@googlemail.com',
'linville@tuxdriver.com',
'linux-wireless@vger.kernel.org',
'netdev@vger.kernel.org',
'linux-kernel@vger.kernel.org'
On Fri, 2014-11-14 at 13:16 +0800, Wang, Yalin wrote:
> Use the inline function instead of directly indexing the array.
>
> This allows some architectures with hardware instructions for bit
> reversals to eliminate the array.
This one is already in -next
commit 7a1283d8f5298437a454ec477384dcd9f9f88bac
Author: Joe Perches <joe@perches.com>
Date: Tue Oct 28 14:18:58 2014 -0700
carl9170: Convert byte_rev_table uses to bitrev8
Use the inline function instead of directly indexing the array.
This allows some architectures with hardware instructions
for bit reversals to eliminate the array.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
^ permalink raw reply [flat|nested] 4+ messages in thread* RE: [PATCH] carl9170: Convert byte_rev_table uses to bitrev8
2014-11-14 5:32 ` Joe Perches
@ 2014-11-14 5:37 ` Wang, Yalin
0 siblings, 0 replies; 4+ messages in thread
From: Wang, Yalin @ 2014-11-14 5:37 UTC (permalink / raw)
To: 'Joe Perches'
Cc: 'chunkeey@googlemail.com',
'linville@tuxdriver.com',
'linux-wireless@vger.kernel.org',
'netdev@vger.kernel.org',
'linux-kernel@vger.kernel.org'
> From: Joe Perches [mailto:joe@perches.com]
> Sent: Friday, November 14, 2014 1:33 PM
> To: Wang, Yalin
> Cc: 'chunkeey@googlemail.com'; 'linville@tuxdriver.com'; 'linux-
> wireless@vger.kernel.org'; 'netdev@vger.kernel.org'; 'linux-
> kernel@vger.kernel.org'
> Subject: Re: [PATCH] carl9170: Convert byte_rev_table uses to bitrev8
>
> On Fri, 2014-11-14 at 13:16 +0800, Wang, Yalin wrote:
> > Use the inline function instead of directly indexing the array.
> >
> > This allows some architectures with hardware instructions for bit
> > reversals to eliminate the array.
>
> This one is already in -next
>
> commit 7a1283d8f5298437a454ec477384dcd9f9f88bac
> Author: Joe Perches <joe@perches.com>
> Date: Tue Oct 28 14:18:58 2014 -0700
>
> carl9170: Convert byte_rev_table uses to bitrev8
>
> Use the inline function instead of directly indexing the array.
>
> This allows some architectures with hardware instructions
> for bit reversals to eliminate the array.
>
> Signed-off-by: Joe Perches <joe@perches.com>
> Signed-off-by: John W. Linville <linville@tuxdriver.com>
>
Got it ,
So I need wait for your another patch to be accepted.
Thanks!
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH RFC] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit
@ 2014-10-24 5:10 Wang, Yalin
2014-10-27 6:37 ` [RFC V2] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction Wang, Yalin
0 siblings, 1 reply; 4+ messages in thread
From: Wang, Yalin @ 2014-10-24 5:10 UTC (permalink / raw)
To: 'Russell King - ARM Linux', 'linux-mm@kvack.org',
'Will Deacon', 'linux-kernel@vger.kernel.org',
'linux-arm-kernel@lists.infradead.org',
'akinobu.mita@gmail.com'
this change add CONFIG_HAVE_ARCH_BITREVERSE config option,
so that we can use arm/arm64 rbit instruction to do bitrev operation
by hardware.
Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
---
arch/arm/Kconfig | 1 +
arch/arm/include/asm/bitrev.h | 21 +++++++++++++++++++++
arch/arm64/Kconfig | 1 +
arch/arm64/include/asm/bitrev.h | 21 +++++++++++++++++++++
include/linux/bitrev.h | 9 +++++++++
lib/Kconfig | 8 ++++++++
lib/bitrev.c | 2 ++
7 files changed, 63 insertions(+)
create mode 100644 arch/arm/include/asm/bitrev.h
create mode 100644 arch/arm64/include/asm/bitrev.h
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 89c4b5c..426cbcc 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -16,6 +16,7 @@ config ARM
select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
select GENERIC_ALLOCATOR
select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
+ select HAVE_ARCH_BITREVERSE if (CPU_V7M || CPU_V7)
select GENERIC_CLOCKEVENTS_BROADCAST if SMP
select GENERIC_IDLE_POLL_SETUP
select GENERIC_IRQ_PROBE
diff --git a/arch/arm/include/asm/bitrev.h b/arch/arm/include/asm/bitrev.h
new file mode 100644
index 0000000..0df5866
--- /dev/null
+++ b/arch/arm/include/asm/bitrev.h
@@ -0,0 +1,21 @@
+#ifndef __ASM_ARM_BITREV_H
+#define __ASM_ARM_BITREV_H
+
+static inline __attribute_const__ u32 __arch_bitrev32(u32 x)
+{
+ __asm__ ("rbit %0, %1" : "=r" (x) : "r" (x));
+ return x;
+}
+
+static inline __attribute_const__ u16 __arch_bitrev16(u16 x)
+{
+ return __arch_bitrev32((u32)x) >> 16;
+}
+
+static inline __attribute_const__ u8 __arch_bitrev8(u8 x)
+{
+ return __arch_bitrev32((u32)x) >> 24;
+}
+
+#endif
+
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index ac9afde..a2566d7 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -35,6 +35,7 @@ config ARM64
select HARDIRQS_SW_RESEND
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_JUMP_LABEL
+ select HAVE_ARCH_BITREVERSE
select HAVE_ARCH_KGDB
select HAVE_ARCH_TRACEHOOK
select HAVE_BPF_JIT
diff --git a/arch/arm64/include/asm/bitrev.h b/arch/arm64/include/asm/bitrev.h
new file mode 100644
index 0000000..5d24c11
--- /dev/null
+++ b/arch/arm64/include/asm/bitrev.h
@@ -0,0 +1,21 @@
+#ifndef __ASM_ARM_BITREV_H
+#define __ASM_ARM_BITREV_H
+
+static inline __attribute_const__ u32 __arch_bitrev32(u32 x)
+{
+ __asm__ ("rbit %w0, %w1" : "=r" (x) : "r" (x));
+ return x;
+}
+
+static inline __attribute_const__ u16 __arch_bitrev16(u16 x)
+{
+ return __arch_bitrev32((u32)x) >> 16;
+}
+
+static inline __attribute_const__ u8 __arch_bitrev8(u8 x)
+{
+ return __arch_bitrev32((u32)x) >> 24;
+}
+
+#endif
+
diff --git a/include/linux/bitrev.h b/include/linux/bitrev.h
index 7ffe03f..ef5b2bb 100644
--- a/include/linux/bitrev.h
+++ b/include/linux/bitrev.h
@@ -3,6 +3,14 @@
#include <linux/types.h>
+#ifdef CONFIG_HAVE_ARCH_BITREVERSE
+#include <asm/bitrev.h>
+
+#define bitrev32 __arch_bitrev32
+#define bitrev16 __arch_bitrev16
+#define bitrev8 __arch_bitrev8
+
+#else
extern u8 const byte_rev_table[256];
static inline u8 bitrev8(u8 byte)
@@ -13,4 +21,5 @@ static inline u8 bitrev8(u8 byte)
extern u16 bitrev16(u16 in);
extern u32 bitrev32(u32 in);
+#endif /* CONFIG_HAVE_ARCH_BITREVERSE */
#endif /* _LINUX_BITREV_H */
diff --git a/lib/Kconfig b/lib/Kconfig
index 54cf309..e0e0453 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -13,6 +13,14 @@ config RAID6_PQ
config BITREVERSE
tristate
+config HAVE_ARCH_BITREVERSE
+ boolean
+ default n
+ help
+ This option provides an config for the architecture which have instruction
+ can do bitreverse operation, we use the hardware instruction if the architecture
+ have this capability.
+
config RATIONAL
boolean
diff --git a/lib/bitrev.c b/lib/bitrev.c
index 3956203..93d637a 100644
--- a/lib/bitrev.c
+++ b/lib/bitrev.c
@@ -1,3 +1,4 @@
+#ifndef CONFIG_HAVE_ARCH_BITREVERSE
#include <linux/types.h>
#include <linux/module.h>
#include <linux/bitrev.h>
@@ -57,3 +58,4 @@ u32 bitrev32(u32 x)
return (bitrev16(x & 0xffff) << 16) | bitrev16(x >> 16);
}
EXPORT_SYMBOL(bitrev32);
+#endif /* CONFIG_HAVE_ARCH_BITREVERSE */
--
2.1.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* [RFC V2] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction
2014-10-24 5:10 [PATCH RFC] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit Wang, Yalin
@ 2014-10-27 6:37 ` Wang, Yalin
2014-10-27 6:46 ` Joe Perches
0 siblings, 1 reply; 4+ messages in thread
From: Wang, Yalin @ 2014-10-27 6:37 UTC (permalink / raw)
To: 'Russell King - ARM Linux', 'linux-mm@kvack.org',
'Will Deacon', 'linux-kernel@vger.kernel.org',
'linux-arm-kernel@lists.infradead.org',
'akinobu.mita@gmail.com'
this change add CONFIG_HAVE_ARCH_BITREVERSE config option,
so that we can use arm/arm64 rbit instruction to do bitrev operation
by hardware.
Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
---
arch/arm/Kconfig | 1 +
arch/arm/include/asm/bitrev.h | 21 +++++++++++++++++++++
arch/arm64/Kconfig | 1 +
arch/arm64/include/asm/bitrev.h | 21 +++++++++++++++++++++
include/linux/bitrev.h | 9 +++++++++
lib/Kconfig | 9 +++++++++
lib/bitrev.c | 2 ++
7 files changed, 64 insertions(+)
create mode 100644 arch/arm/include/asm/bitrev.h
create mode 100644 arch/arm64/include/asm/bitrev.h
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 89c4b5c..426cbcc 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -16,6 +16,7 @@ config ARM
select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
select GENERIC_ALLOCATOR
select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
+ select HAVE_ARCH_BITREVERSE if (CPU_V7M || CPU_V7)
select GENERIC_CLOCKEVENTS_BROADCAST if SMP
select GENERIC_IDLE_POLL_SETUP
select GENERIC_IRQ_PROBE
diff --git a/arch/arm/include/asm/bitrev.h b/arch/arm/include/asm/bitrev.h
new file mode 100644
index 0000000..0df5866
--- /dev/null
+++ b/arch/arm/include/asm/bitrev.h
@@ -0,0 +1,21 @@
+#ifndef __ASM_ARM_BITREV_H
+#define __ASM_ARM_BITREV_H
+
+static inline __attribute_const__ u32 __arch_bitrev32(u32 x)
+{
+ __asm__ ("rbit %0, %1" : "=r" (x) : "r" (x));
+ return x;
+}
+
+static inline __attribute_const__ u16 __arch_bitrev16(u16 x)
+{
+ return __arch_bitrev32((u32)x) >> 16;
+}
+
+static inline __attribute_const__ u8 __arch_bitrev8(u8 x)
+{
+ return __arch_bitrev32((u32)x) >> 24;
+}
+
+#endif
+
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 9532f8d..263c28c 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -36,6 +36,7 @@ config ARM64
select HARDIRQS_SW_RESEND
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_JUMP_LABEL
+ select HAVE_ARCH_BITREVERSE
select HAVE_ARCH_KGDB
select HAVE_ARCH_TRACEHOOK
select HAVE_BPF_JIT
diff --git a/arch/arm64/include/asm/bitrev.h b/arch/arm64/include/asm/bitrev.h
new file mode 100644
index 0000000..5d24c11
--- /dev/null
+++ b/arch/arm64/include/asm/bitrev.h
@@ -0,0 +1,21 @@
+#ifndef __ASM_ARM_BITREV_H
+#define __ASM_ARM_BITREV_H
+
+static inline __attribute_const__ u32 __arch_bitrev32(u32 x)
+{
+ __asm__ ("rbit %w0, %w1" : "=r" (x) : "r" (x));
+ return x;
+}
+
+static inline __attribute_const__ u16 __arch_bitrev16(u16 x)
+{
+ return __arch_bitrev32((u32)x) >> 16;
+}
+
+static inline __attribute_const__ u8 __arch_bitrev8(u8 x)
+{
+ return __arch_bitrev32((u32)x) >> 24;
+}
+
+#endif
+
diff --git a/include/linux/bitrev.h b/include/linux/bitrev.h
index 7ffe03f..ef5b2bb 100644
--- a/include/linux/bitrev.h
+++ b/include/linux/bitrev.h
@@ -3,6 +3,14 @@
#include <linux/types.h>
+#ifdef CONFIG_HAVE_ARCH_BITREVERSE
+#include <asm/bitrev.h>
+
+#define bitrev32 __arch_bitrev32
+#define bitrev16 __arch_bitrev16
+#define bitrev8 __arch_bitrev8
+
+#else
extern u8 const byte_rev_table[256];
static inline u8 bitrev8(u8 byte)
@@ -13,4 +21,5 @@ static inline u8 bitrev8(u8 byte)
extern u16 bitrev16(u16 in);
extern u32 bitrev32(u32 in);
+#endif /* CONFIG_HAVE_ARCH_BITREVERSE */
#endif /* _LINUX_BITREV_H */
diff --git a/lib/Kconfig b/lib/Kconfig
index 54cf309..cd177ca 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -13,6 +13,15 @@ config RAID6_PQ
config BITREVERSE
tristate
+config HAVE_ARCH_BITREVERSE
+ boolean
+ default n
+ depends on BITREVERSE
+ help
+ This option provides an config for the architecture which have instruction
+ can do bitreverse operation, we use the hardware instruction if the architecture
+ have this capability.
+
config RATIONAL
boolean
diff --git a/lib/bitrev.c b/lib/bitrev.c
index 3956203..93d637a 100644
--- a/lib/bitrev.c
+++ b/lib/bitrev.c
@@ -1,3 +1,4 @@
+#ifndef CONFIG_HAVE_ARCH_BITREVERSE
#include <linux/types.h>
#include <linux/module.h>
#include <linux/bitrev.h>
@@ -57,3 +58,4 @@ u32 bitrev32(u32 x)
return (bitrev16(x & 0xffff) << 16) | bitrev16(x >> 16);
}
EXPORT_SYMBOL(bitrev32);
+#endif /* CONFIG_HAVE_ARCH_BITREVERSE */
--
2.1.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [RFC V2] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction
2014-10-27 6:37 ` [RFC V2] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction Wang, Yalin
@ 2014-10-27 6:46 ` Joe Perches
2014-10-28 21:18 ` [PATCH] carl9170: Convert byte_rev_table uses to bitrev8 Joe Perches
0 siblings, 1 reply; 4+ messages in thread
From: Joe Perches @ 2014-10-27 6:46 UTC (permalink / raw)
To: Wang, Yalin
Cc: 'Russell King - ARM Linux', 'linux-mm@kvack.org',
'Will Deacon', 'linux-kernel@vger.kernel.org',
'linux-arm-kernel@lists.infradead.org',
'akinobu.mita@gmail.com'
On Mon, 2014-10-27 at 14:37 +0800, Wang, Yalin wrote:
> this change add CONFIG_HAVE_ARCH_BITREVERSE config option,
> so that we can use arm/arm64 rbit instruction to do bitrev operation
> by hardware.
>
> Signed-off-by: Yalin Wang <yalin.wang@sonymobile.com>
> ---
> arch/arm/Kconfig | 1 +
> arch/arm/include/asm/bitrev.h | 21 +++++++++++++++++++++
> arch/arm64/Kconfig | 1 +
> arch/arm64/include/asm/bitrev.h | 21 +++++++++++++++++++++
> include/linux/bitrev.h | 9 +++++++++
> lib/Kconfig | 9 +++++++++
> lib/bitrev.c | 2 ++
> 7 files changed, 64 insertions(+)
> create mode 100644 arch/arm/include/asm/bitrev.h
> create mode 100644 arch/arm64/include/asm/bitrev.h
>
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 89c4b5c..426cbcc 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -16,6 +16,7 @@ config ARM
> select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
> select GENERIC_ALLOCATOR
> select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
> + select HAVE_ARCH_BITREVERSE if (CPU_V7M || CPU_V7)
> select GENERIC_CLOCKEVENTS_BROADCAST if SMP
> select GENERIC_IDLE_POLL_SETUP
> select GENERIC_IRQ_PROBE
> diff --git a/arch/arm/include/asm/bitrev.h b/arch/arm/include/asm/bitrev.h
> new file mode 100644
> index 0000000..0df5866
> --- /dev/null
> +++ b/arch/arm/include/asm/bitrev.h
> @@ -0,0 +1,21 @@
> +#ifndef __ASM_ARM_BITREV_H
> +#define __ASM_ARM_BITREV_H
> +
> +static inline __attribute_const__ u32 __arch_bitrev32(u32 x)
> +{
> + __asm__ ("rbit %0, %1" : "=r" (x) : "r" (x));
> + return x;
> +}
> +
> +static inline __attribute_const__ u16 __arch_bitrev16(u16 x)
> +{
> + return __arch_bitrev32((u32)x) >> 16;
> +}
> +
> +static inline __attribute_const__ u8 __arch_bitrev8(u8 x)
> +{
> + return __arch_bitrev32((u32)x) >> 24;
> +}
> +
> +#endif
> +
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 9532f8d..263c28c 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -36,6 +36,7 @@ config ARM64
> select HARDIRQS_SW_RESEND
> select HAVE_ARCH_AUDITSYSCALL
> select HAVE_ARCH_JUMP_LABEL
> + select HAVE_ARCH_BITREVERSE
> select HAVE_ARCH_KGDB
> select HAVE_ARCH_TRACEHOOK
> select HAVE_BPF_JIT
> diff --git a/arch/arm64/include/asm/bitrev.h b/arch/arm64/include/asm/bitrev.h
> new file mode 100644
> index 0000000..5d24c11
> --- /dev/null
> +++ b/arch/arm64/include/asm/bitrev.h
> @@ -0,0 +1,21 @@
> +#ifndef __ASM_ARM_BITREV_H
> +#define __ASM_ARM_BITREV_H
> +
> +static inline __attribute_const__ u32 __arch_bitrev32(u32 x)
> +{
> + __asm__ ("rbit %w0, %w1" : "=r" (x) : "r" (x));
> + return x;
> +}
> +
> +static inline __attribute_const__ u16 __arch_bitrev16(u16 x)
> +{
> + return __arch_bitrev32((u32)x) >> 16;
> +}
> +
> +static inline __attribute_const__ u8 __arch_bitrev8(u8 x)
> +{
> + return __arch_bitrev32((u32)x) >> 24;
> +}
> +
> +#endif
> +
> diff --git a/include/linux/bitrev.h b/include/linux/bitrev.h
> index 7ffe03f..ef5b2bb 100644
> --- a/include/linux/bitrev.h
> +++ b/include/linux/bitrev.h
> @@ -3,6 +3,14 @@
>
> #include <linux/types.h>
>
> +#ifdef CONFIG_HAVE_ARCH_BITREVERSE
> +#include <asm/bitrev.h>
> +
> +#define bitrev32 __arch_bitrev32
> +#define bitrev16 __arch_bitrev16
> +#define bitrev8 __arch_bitrev8
> +
> +#else
> extern u8 const byte_rev_table[256];
If this is done, the direct uses of byte_rev_table in
drivers/net/wireless/ath/carl9170/phy.c and
sound/usb/6fire/firmware.c should be converted too?
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH] carl9170: Convert byte_rev_table uses to bitrev8
2014-10-27 6:46 ` Joe Perches
@ 2014-10-28 21:18 ` Joe Perches
0 siblings, 0 replies; 4+ messages in thread
From: Joe Perches @ 2014-10-28 21:18 UTC (permalink / raw)
To: Christian Lamparter
Cc: John W. Linville, Wang, Yalin, Russell King, linux-mm,
Will Deacon, Akinobu Mita, linux-arm-kernel, linux-wireless,
netdev, LKML
Use the inline function instead of directly indexing the array.
This allows some architectures with hardware instructions
for bit reversals to eliminate the array.
Signed-off-by: Joe Perches <joe@perches.com>
---
On Sun, 2014-10-26 at 23:46 -0700, Joe Perches wrote:
> On Mon, 2014-10-27 at 14:37 +0800, Wang, Yalin wrote:
> > this change add CONFIG_HAVE_ARCH_BITREVERSE config option,
> > so that we can use arm/arm64 rbit instruction to do bitrev operation
> > by hardware.
[]
> > diff --git a/include/linux/bitrev.h b/include/linux/bitrev.h
> > index 7ffe03f..ef5b2bb 100644
> > --- a/include/linux/bitrev.h
> > +++ b/include/linux/bitrev.h
> > @@ -3,6 +3,14 @@
> >
> > #include <linux/types.h>
> >
> > +#ifdef CONFIG_HAVE_ARCH_BITREVERSE
> > +#include <asm/bitrev.h>
> > +
> > +#define bitrev32 __arch_bitrev32
> > +#define bitrev16 __arch_bitrev16
> > +#define bitrev8 __arch_bitrev8
> > +
> > +#else
> > extern u8 const byte_rev_table[256];
drivers/net/wireless/ath/carl9170/phy.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/ath/carl9170/phy.c b/drivers/net/wireless/ath/carl9170/phy.c
index b80b213..dca6df1 100644
--- a/drivers/net/wireless/ath/carl9170/phy.c
+++ b/drivers/net/wireless/ath/carl9170/phy.c
@@ -994,7 +994,7 @@ static int carl9170_init_rf_bank4_pwr(struct ar9170 *ar, bool band5ghz,
refsel0 = 0;
refsel1 = 1;
}
- chansel = byte_rev_table[chansel];
+ chansel = bitrev8(chansel);
} else {
if (freq == 2484) {
chansel = 10 + (freq - 2274) / 5;
@@ -1002,7 +1002,7 @@ static int carl9170_init_rf_bank4_pwr(struct ar9170 *ar, bool band5ghz,
} else
chansel = 16 + (freq - 2272) / 5;
chansel *= 4;
- chansel = byte_rev_table[chansel];
+ chansel = bitrev8(chansel);
}
d1 = chansel;
^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2014-11-14 5:37 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2014-11-14 5:16 [PATCH] carl9170: Convert byte_rev_table uses to bitrev8 Wang, Yalin
2014-11-14 5:32 ` Joe Perches
2014-11-14 5:37 ` Wang, Yalin
-- strict thread matches above, loose matches on Subject: below --
2014-10-24 5:10 [PATCH RFC] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit Wang, Yalin
2014-10-27 6:37 ` [RFC V2] arm/arm64:add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction Wang, Yalin
2014-10-27 6:46 ` Joe Perches
2014-10-28 21:18 ` [PATCH] carl9170: Convert byte_rev_table uses to bitrev8 Joe Perches
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