From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751460AbdBXEkR (ORCPT ); Thu, 23 Feb 2017 23:40:17 -0500 Received: from mail-pg0-f66.google.com ([74.125.83.66]:34532 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751057AbdBXEkK (ORCPT ); Thu, 23 Feb 2017 23:40:10 -0500 From: Stafford Horne To: Jonas Bonn , Stefan Kristiansson Cc: linux@roeck-us.net, openrisc@lists.librecores.org, linux-kernel@vger.kernel.org, Olof Kindgren , Stafford Horne Subject: [PATCH v4 14/24] openrisc: Add optimized memset Date: Fri, 24 Feb 2017 13:32:34 +0900 Message-Id: <3002db294994a2f8927a09bde71e62b07cd8059d.1487910170.git.shorne@gmail.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Olof Kindgren This adds a hand-optimized assembler version of memset and sets __HAVE_ARCH_MEMSET to use this version instead of the generic C routine Signed-off-by: Olof Kindgren Signed-off-by: Stafford Horne --- arch/openrisc/include/asm/string.h | 7 +++ arch/openrisc/kernel/or32_ksyms.c | 1 + arch/openrisc/lib/Makefile | 2 +- arch/openrisc/lib/memset.S | 98 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 107 insertions(+), 1 deletion(-) create mode 100644 arch/openrisc/include/asm/string.h create mode 100644 arch/openrisc/lib/memset.S diff --git a/arch/openrisc/include/asm/string.h b/arch/openrisc/include/asm/string.h new file mode 100644 index 0000000..33470d4 --- /dev/null +++ b/arch/openrisc/include/asm/string.h @@ -0,0 +1,7 @@ +#ifndef __ASM_OPENRISC_STRING_H +#define __ASM_OPENRISC_STRING_H + +#define __HAVE_ARCH_MEMSET +extern void *memset(void *s, int c, __kernel_size_t n); + +#endif /* __ASM_OPENRISC_STRING_H */ diff --git a/arch/openrisc/kernel/or32_ksyms.c b/arch/openrisc/kernel/or32_ksyms.c index 86e31cf..5c4695d 100644 --- a/arch/openrisc/kernel/or32_ksyms.c +++ b/arch/openrisc/kernel/or32_ksyms.c @@ -44,3 +44,4 @@ DECLARE_EXPORT(__ashldi3); DECLARE_EXPORT(__lshrdi3); EXPORT_SYMBOL(__copy_tofrom_user); +EXPORT_SYMBOL(memset); diff --git a/arch/openrisc/lib/Makefile b/arch/openrisc/lib/Makefile index 966f65d..67c583e 100644 --- a/arch/openrisc/lib/Makefile +++ b/arch/openrisc/lib/Makefile @@ -2,4 +2,4 @@ # Makefile for or32 specific library files.. # -obj-y = string.o delay.o +obj-y = memset.o string.o delay.o diff --git a/arch/openrisc/lib/memset.S b/arch/openrisc/lib/memset.S new file mode 100644 index 0000000..92cc2ea --- /dev/null +++ b/arch/openrisc/lib/memset.S @@ -0,0 +1,98 @@ +/* + * OpenRISC memset.S + * + * Hand-optimized assembler version of memset for OpenRISC. + * Algorithm inspired by several other arch-specific memset routines + * in the kernel tree + * + * Copyright (C) 2015 Olof Kindgren + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + + .global memset + .type memset, @function +memset: + /* arguments: + * r3 = *s + * r4 = c + * r5 = n + * r13, r15, r17, r19 used as temp regs + */ + + /* Exit if n == 0 */ + l.sfeqi r5, 0 + l.bf 4f + + /* Truncate c to char */ + l.andi r13, r4, 0xff + + /* Skip word extension if c is 0 */ + l.sfeqi r13, 0 + l.bf 1f + /* Check for at least two whole words (8 bytes) */ + l.sfleui r5, 7 + + /* Extend char c to 32-bit word cccc in r13 */ + l.slli r15, r13, 16 // r13 = 000c, r15 = 0c00 + l.or r13, r13, r15 // r13 = 0c0c, r15 = 0c00 + l.slli r15, r13, 8 // r13 = 0c0c, r15 = c0c0 + l.or r13, r13, r15 // r13 = cccc, r15 = c0c0 + +1: l.addi r19, r3, 0 // Set r19 = src + /* Jump to byte copy loop if less than two words */ + l.bf 3f + l.or r17, r5, r0 // Set r17 = n + + /* Mask out two LSBs to check alignment */ + l.andi r15, r3, 0x3 + + /* lsb == 00, jump to word copy loop */ + l.sfeqi r15, 0 + l.bf 2f + l.addi r19, r3, 0 // Set r19 = src + + /* lsb == 01,10 or 11 */ + l.sb 0(r3), r13 // *src = c + l.addi r17, r17, -1 // Decrease n + + l.sfeqi r15, 3 + l.bf 2f + l.addi r19, r3, 1 // src += 1 + + /* lsb == 01 or 10 */ + l.sb 1(r3), r13 // *(src+1) = c + l.addi r17, r17, -1 // Decrease n + + l.sfeqi r15, 2 + l.bf 2f + l.addi r19, r3, 2 // src += 2 + + /* lsb == 01 */ + l.sb 2(r3), r13 // *(src+2) = c + l.addi r17, r17, -1 // Decrease n + l.addi r19, r3, 3 // src += 3 + + /* Word copy loop */ +2: l.sw 0(r19), r13 // *src = cccc + l.addi r17, r17, -4 // Decrease n + l.sfgeui r17, 4 + l.bf 2b + l.addi r19, r19, 4 // Increase src + + /* When n > 0, copy the remaining bytes, otherwise jump to exit */ + l.sfeqi r17, 0 + l.bf 4f + + /* Byte copy loop */ +3: l.addi r17, r17, -1 // Decrease n + l.sb 0(r19), r13 // *src = cccc + l.sfnei r17, 0 + l.bf 3b + l.addi r19, r19, 1 // Increase src + +4: l.jr r9 + l.ori r11, r3, 0 -- 2.9.3