From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Wed, 25 Sep 2024 18:04:15 +0200 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1stUUw-002eje-00 for lore@lore.pengutronix.de; Wed, 25 Sep 2024 18:04:15 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1stUUw-0006ty-04 for lore@pengutronix.de; Wed, 25 Sep 2024 18:04:14 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Cc:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=J+BUygcu6nLQM8+71g3XqlA/ehUkiloqzLa1ioF3cgU=; b=eL0Njl8ZH3ON1CBEe3WEktCAhq zTdBaAu/xnITTCntcYsS9HNIee3nrNTVk3UJEGEfQQ4wlrf004xdpp1840Q8bSGxSCiz4RXj5YETs 6P+IZxqucGfM69lE/bTSrJiZkgsACo5ewrH4VU0PSLDwc/bhrY7uGeul4xy48LSx/EOsTTJru6sCP jwXalJsVv7HI9NkMonfoueMqzV85wEcW0ArvpOioiI1KIFuiUKT5wpywFIdDqLrMBZ33bLDghBjtC pZGVfNep9WMLvhZKekLE7FV3Coa5eeew8jj0BQr4s86rfp17CfqQwgF8WtvCO8GhO70WbtjJfC3eI ArpG0f2Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1stUUS-00000005zHr-0u4I; Wed, 25 Sep 2024 16:03:44 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1stUUO-00000005zHC-3qWE for barebox@lists.infradead.org; Wed, 25 Sep 2024 16:03:42 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1stUUN-0006ny-Ky; Wed, 25 Sep 2024 18:03:39 +0200 Message-ID: Date: Wed, 25 Sep 2024 18:03:39 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Sascha Hauer , "open list:BAREBOX" References: <20240925-arm-assembly-memmove-v1-0-0d92103658a0@pengutronix.de> <20240925-arm-assembly-memmove-v1-5-0d92103658a0@pengutronix.de> Content-Language: en-US From: Ahmad Fatoum In-Reply-To: <20240925-arm-assembly-memmove-v1-5-0d92103658a0@pengutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240925_090341_153247_8666D45A X-CRM114-Status: GOOD ( 23.25 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-4.0 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 05/10] ARM: update findbit.S from Linux X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) On 25.09.24 15:55, Sascha Hauer wrote: > This updates findbit.S from Linux Please mention version. > > Signed-off-by: Sascha Hauer > --- > arch/arm/lib32/findbit.S | 243 ++++++++++++++++++----------------------------- > 1 file changed, 94 insertions(+), 149 deletions(-) > > diff --git a/arch/arm/lib32/findbit.S b/arch/arm/lib32/findbit.S > index 82a0f34dc2..b7ac2d3c07 100644 > --- a/arch/arm/lib32/findbit.S > +++ b/arch/arm/lib32/findbit.S > @@ -1,9 +1,8 @@ > /* SPDX-License-Identifier: GPL-2.0-only */ > -/* SPDX-FileCopyrightText: 1995-2000 Russell King */ > - > /* > - * Originally from Linux kernel > - * arch/arm/lib/findbit.S > + * linux/arch/arm/lib/findbit.S > + * > + * Copyright (C) 1995-2000 Russell King > * > * 16th March 2001 - John Ripley > * Fixed so that "size" is an exclusive not an inclusive quantity. > @@ -13,182 +12,128 @@ > */ > #include > #include > +#include > .text > > -/* > - * Purpose : Find a 'zero' bit > - * Prototype: int find_first_zero_bit(void *addr, unsigned int maxbit); > - */ > -ENTRY(_find_first_zero_bit_le) > - teq r1, #0 > - beq 3f > - mov r2, #0 > -1: > - ARM( ldrb r3, [r0, r2, lsr #3] ) > - THUMB( lsr r3, r2, #3 ) > - THUMB( ldrb r3, [r0, r3] ) > - eors r3, r3, #0xff @ invert bits > - bne .L_found @ any now set - found zero bit > - add r2, r2, #8 @ next bit pointer > -2: cmp r2, r1 @ any more? > - blo 1b > -3: mov r0, r1 @ no free bits > - mov pc, lr > -ENDPROC(_find_first_zero_bit_le) > - > -/* > - * Purpose : Find next 'zero' bit > - * Prototype: int find_next_zero_bit(void *addr, unsigned int maxbit, int offset) > - */ > -ENTRY(_find_next_zero_bit_le) > - teq r1, #0 > - beq 3b > - ands ip, r2, #7 > - beq 1b @ If new byte, goto old routine > - ARM( ldrb r3, [r0, r2, lsr #3] ) > - THUMB( lsr r3, r2, #3 ) > - THUMB( ldrb r3, [r0, r3] ) > - eor r3, r3, #0xff @ now looking for a 1 bit > - movs r3, r3, lsr ip @ shift off unused bits > - bne .L_found > - orr r2, r2, #7 @ if zero, then no bits here > - add r2, r2, #1 @ align bit pointer > - b 2b @ loop for next bit > -ENDPROC(_find_next_zero_bit_le) > +#ifdef __ARMEB__ > +#define SWAB_ENDIAN le > +#else > +#define SWAB_ENDIAN be > +#endif > > -/* > - * Purpose : Find a 'one' bit > - * Prototype: int find_first_bit(const unsigned long *addr, unsigned int maxbit); > - */ > -ENTRY(_find_first_bit_le) > + .macro find_first, endian, set, name > +ENTRY(_find_first_\name\()bit_\endian) > + UNWIND( .fnstart) > teq r1, #0 > beq 3f > mov r2, #0 > -1: > - ARM( ldrb r3, [r0, r2, lsr #3] ) > - THUMB( lsr r3, r2, #3 ) > - THUMB( ldrb r3, [r0, r3] ) > - movs r3, r3 > - bne .L_found @ any now set - found zero bit > - add r2, r2, #8 @ next bit pointer > +1: ldr r3, [r0], #4 > + .ifeq \set > + mvns r3, r3 @ invert/test bits > + .else > + movs r3, r3 @ test bits > + .endif > + .ifc \endian, SWAB_ENDIAN > + bne .L_found_swab > + .else > + bne .L_found @ found the bit? > + .endif > + add r2, r2, #32 @ next index > 2: cmp r2, r1 @ any more? > blo 1b > -3: mov r0, r1 @ no free bits > - mov pc, lr > -ENDPROC(_find_first_bit_le) > +3: mov r0, r1 @ no more bits > + ret lr > + UNWIND( .fnend) > +ENDPROC(_find_first_\name\()bit_\endian) > + .endm > > -/* > - * Purpose : Find next 'one' bit > - * Prototype: int find_next_zero_bit(void *addr, unsigned int maxbit, int offset) > - */ > -ENTRY(_find_next_bit_le) > - teq r1, #0 > - beq 3b > - ands ip, r2, #7 > - beq 1b @ If new byte, goto old routine > - ARM( ldrb r3, [r0, r2, lsr #3] ) > - THUMB( lsr r3, r2, #3 ) > - THUMB( ldrb r3, [r0, r3] ) > + .macro find_next, endian, set, name > +ENTRY(_find_next_\name\()bit_\endian) > + UNWIND( .fnstart) > + cmp r2, r1 > + bhs 3b > + mov ip, r2, lsr #5 @ word index > + add r0, r0, ip, lsl #2 > + ands ip, r2, #31 @ bit position > + beq 1b > + ldr r3, [r0], #4 > + .ifeq \set > + mvn r3, r3 @ invert bits > + .endif > + .ifc \endian, SWAB_ENDIAN > + rev_l r3, ip > + .if .Lrev_l_uses_tmp > + @ we need to recompute ip because rev_l will have overwritten > + @ it. > + and ip, r2, #31 @ bit position > + .endif > + .endif > movs r3, r3, lsr ip @ shift off unused bits > bne .L_found > - orr r2, r2, #7 @ if zero, then no bits here > + orr r2, r2, #31 @ no zero bits > add r2, r2, #1 @ align bit pointer > b 2b @ loop for next bit > -ENDPROC(_find_next_bit_le) > + UNWIND( .fnend) > +ENDPROC(_find_next_\name\()bit_\endian) > + .endm > > -#ifdef __ARMEB__ > + .macro find_bit, endian, set, name > + find_first \endian, \set, \name > + find_next \endian, \set, \name > + .endm > > -ENTRY(_find_first_zero_bit_be) > - teq r1, #0 > - beq 3f > - mov r2, #0 > -1: eor r3, r2, #0x18 @ big endian byte ordering > - ARM( ldrb r3, [r0, r3, lsr #3] ) > - THUMB( lsr r3, #3 ) > - THUMB( ldrb r3, [r0, r3] ) > - eors r3, r3, #0xff @ invert bits > - bne .L_found @ any now set - found zero bit > - add r2, r2, #8 @ next bit pointer > -2: cmp r2, r1 @ any more? > - blo 1b > -3: mov r0, r1 @ no free bits > - mov pc, lr > -ENDPROC(_find_first_zero_bit_be) > +/* _find_first_zero_bit_le and _find_next_zero_bit_le */ > + find_bit le, 0, zero_ > > -ENTRY(_find_next_zero_bit_be) > - teq r1, #0 > - beq 3b > - ands ip, r2, #7 > - beq 1b @ If new byte, goto old routine > - eor r3, r2, #0x18 @ big endian byte ordering > - ARM( ldrb r3, [r0, r3, lsr #3] ) > - THUMB( lsr r3, #3 ) > - THUMB( ldrb r3, [r0, r3] ) > - eor r3, r3, #0xff @ now looking for a 1 bit > - movs r3, r3, lsr ip @ shift off unused bits > - bne .L_found > - orr r2, r2, #7 @ if zero, then no bits here > - add r2, r2, #1 @ align bit pointer > - b 2b @ loop for next bit > -ENDPROC(_find_next_zero_bit_be) > +/* _find_first_bit_le and _find_next_bit_le */ > + find_bit le, 1 > > -ENTRY(_find_first_bit_be) > - teq r1, #0 > - beq 3f > - mov r2, #0 > -1: eor r3, r2, #0x18 @ big endian byte ordering > - ARM( ldrb r3, [r0, r3, lsr #3] ) > - THUMB( lsr r3, #3 ) > - THUMB( ldrb r3, [r0, r3] ) > - movs r3, r3 > - bne .L_found @ any now set - found zero bit > - add r2, r2, #8 @ next bit pointer > -2: cmp r2, r1 @ any more? > - blo 1b > -3: mov r0, r1 @ no free bits > - mov pc, lr > -ENDPROC(_find_first_bit_be) > +#ifdef __ARMEB__ > > -ENTRY(_find_next_bit_be) > - teq r1, #0 > - beq 3b > - ands ip, r2, #7 > - beq 1b @ If new byte, goto old routine > - eor r3, r2, #0x18 @ big endian byte ordering > - ARM( ldrb r3, [r0, r3, lsr #3] ) > - THUMB( lsr r3, #3 ) > - THUMB( ldrb r3, [r0, r3] ) > - movs r3, r3, lsr ip @ shift off unused bits > - bne .L_found > - orr r2, r2, #7 @ if zero, then no bits here > - add r2, r2, #1 @ align bit pointer > - b 2b @ loop for next bit > -ENDPROC(_find_next_bit_be) > +/* _find_first_zero_bit_be and _find_next_zero_bit_be */ > + find_bit be, 0, zero_ > + > +/* _find_first_bit_be and _find_next_bit_be */ > + find_bit be, 1 > > #endif > > /* > * One or more bits in the LSB of r3 are assumed to be set. > */ > +.L_found_swab: > + UNWIND( .fnstart) > + rev_l r3, ip > .L_found: > -#if __LINUX_ARM_ARCH__ >= 5 > +#if __LINUX_ARM_ARCH__ >= 7 > + rbit r3, r3 @ reverse bits > + clz r3, r3 @ count high zero bits > + add r0, r2, r3 @ add offset of first set bit > +#elif __LINUX_ARM_ARCH__ >= 5 > rsb r0, r3, #0 > - and r3, r3, r0 > - clz r3, r3 > - rsb r3, r3, #31 > - add r0, r2, r3 > + and r3, r3, r0 @ mask out lowest bit set > + clz r3, r3 @ count high zero bits > + rsb r3, r3, #31 @ offset of first set bit > + add r0, r2, r3 @ add offset of first set bit > #else > - tst r3, #0x0f > + mov ip, #~0 > + tst r3, ip, lsr #16 @ test bits 0-15 > + addeq r2, r2, #16 > + moveq r3, r3, lsr #16 > + tst r3, #0x00ff > + addeq r2, r2, #8 > + moveq r3, r3, lsr #8 > + tst r3, #0x000f > addeq r2, r2, #4 > - movne r3, r3, lsl #4 > - tst r3, #0x30 > + moveq r3, r3, lsr #4 > + tst r3, #0x0003 > addeq r2, r2, #2 > - movne r3, r3, lsl #2 > - tst r3, #0x40 > + moveq r3, r3, lsr #2 > + tst r3, #0x0001 > addeq r2, r2, #1 > mov r0, r2 > #endif > cmp r1, r0 @ Clamp to maxbit > movlo r0, r1 > - mov pc, lr > - > + ret lr > + UNWIND( .fnend) > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |