From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joshua Clayton Subject: [PATCH v6 2/5] lib: implement __arch_bitrev8x4() Date: Fri, 16 Dec 2016 15:17:51 -0800 Message-ID: <6c1c052d3c1d0c02a791aaaf8e114360ab1cb4e7.1481918884.git.stillcompiling@gmail.com> References: Return-path: In-Reply-To: In-Reply-To: References: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alan Tull , Moritz Fischer , Russell King , Catalin Marinas , Will Deacon , Shawn Guo , Sascha Hauer , Fabio Estevam Cc: Mark Rutland , Rob Herring , Anatolij Gustschin , Joshua Clayton , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-fpga-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Implement faster bitrev8x4() for arm, arm64 and mips, all the platforms with CONFIG_HAVE_ARCH_BITREVERSE. ARM platforms just need a byteswap added to the existing __arch_bitrev32() Amusingly, the mips implementation is exactly the opposite, requiring removal of the byteswap from its __arch_bitrev32() Signed-off-by: Joshua Clayton --- arch/arm/include/asm/bitrev.h | 6 ++++++ arch/arm64/include/asm/bitrev.h | 6 ++++++ arch/mips/include/asm/bitrev.h | 6 ++++++ include/linux/bitrev.h | 1 + 4 files changed, 19 insertions(+) diff --git a/arch/arm/include/asm/bitrev.h b/arch/arm/include/asm/bitrev.h index ec291c3..9482f78 100644 --- a/arch/arm/include/asm/bitrev.h +++ b/arch/arm/include/asm/bitrev.h @@ -17,4 +17,10 @@ static __always_inline __attribute_const__ u8 __arch_bitrev8(u8 x) return __arch_bitrev32((u32)x) >> 24; } +static __always_inline __attribute_const__ u32 __arch_bitrev8x4(u32 x) +{ + __asm__ ("rbit %0, %1; rev %0, %0" : "=r" (x) : "r" (x)); + return x; +} + #endif diff --git a/arch/arm64/include/asm/bitrev.h b/arch/arm64/include/asm/bitrev.h index a5a0c36..1801078 100644 --- a/arch/arm64/include/asm/bitrev.h +++ b/arch/arm64/include/asm/bitrev.h @@ -16,4 +16,10 @@ static __always_inline __attribute_const__ u8 __arch_bitrev8(u8 x) return __arch_bitrev32((u32)x) >> 24; } +static __always_inline __attribute_const__ u32 __arch_bitrev8x4(u32 x) +{ + __asm__ ("rbit %0, %1; rev %0, %0" : "=r" (x) : "r" (x)); + return x; +} + #endif diff --git a/arch/mips/include/asm/bitrev.h b/arch/mips/include/asm/bitrev.h index bc739a4..9ac6439 100644 --- a/arch/mips/include/asm/bitrev.h +++ b/arch/mips/include/asm/bitrev.h @@ -27,4 +27,10 @@ static __always_inline __attribute_const__ u8 __arch_bitrev8(u8 x) return ret; } +static __always_inline __attribute_const__ u32 __arch_bitrev8x4(u32 x) +{ + u32 ret; + asm("bitswap %0, %1" : "=r"(ret) : "r"(x)); + return ret; +} #endif /* __MIPS_ASM_BITREV_H__ */ diff --git a/include/linux/bitrev.h b/include/linux/bitrev.h index 868dcb6..b1cfa1a 100644 --- a/include/linux/bitrev.h +++ b/include/linux/bitrev.h @@ -9,6 +9,7 @@ #define __bitrev32 __arch_bitrev32 #define __bitrev16 __arch_bitrev16 #define __bitrev8 __arch_bitrev8 +#define __bitrev8x4 __arch_bitrev8x4 #else extern u8 const byte_rev_table[256]; -- 2.9.3 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html