From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9670A79D2; Fri, 4 Apr 2025 02:52:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=150.107.74.76 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743735135; cv=none; b=WDnVBNQ1n29HiyYFahCTHdlC419ap+10DrpIDFF/2obZ50IsuLXW9VhtzyaNl2OofBb5PvjhO8beBg14U6bth2L2xLu4N6345NdsLcB3DNQ8vm3YXo88ajDLWBSFr51KgRFPA21UQaBEDJ/qY/fgTU4wY/HyWQHQ2DMyS69y+nE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743735135; c=relaxed/simple; bh=bD316i6CC1/1PO6OVutB+NKMwcDuOGm8uB+gBAMy1aY=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=K7BGAXgRJBaYgy882XwyrAGUE7OjA/N4hFsX9ey+kymaBRjwO3yN6l4dRLGfjrA97YpKku27AfnqjIRh8vTOIfQcVUFjd31XetXHelOeHeOO50AOT3W3khcAjZFDDMWpo4LzLclk2EARQZB9mbONUSW1/4bR72ziS8FO1eUhawI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ozlabs.org; spf=pass smtp.mailfrom=ozlabs.org; dkim=pass (2048-bit key) header.d=ozlabs.org header.i=@ozlabs.org header.b=cECX35JO; arc=none smtp.client-ip=150.107.74.76 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ozlabs.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ozlabs.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ozlabs.org header.i=@ozlabs.org header.b="cECX35JO" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ozlabs.org; s=201707; t=1743735129; bh=bD316i6CC1/1PO6OVutB+NKMwcDuOGm8uB+gBAMy1aY=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=cECX35JOUju7Gk7KN9dGvxDxapcSnbwiA6dOiSg+vBhsG/elnQAFs/XdV5+g6WWt6 SLCnm/Ucw8BBGVyk5Ijw+fksySSB6WceeM1CY3gFBmJT9wI6tsBebEb6+o92tkuHS5 W86JYzh62/EpgW4D48keOw4sg7Ga/HdeNdrRLxuxYO34VtQbiLDviSnDbvtFpckqcj TGdMnQGS1Jnjggap/FvXRhM0sVlGzBGbEYD9iWoiIUwTri9g8KO5FCGJ0q8N8pRRps Oit9X8P5fuYFOcEsQWRIudq6HVF68PYjzIGIF6CP6n5FfeUTK/dStmQfFMHikk8lv2 VEX5mekmjKhpA== Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mail.ozlabs.org (Postfix) with ESMTPSA id 4ZTNRc5mVdz4wyh; Fri, 4 Apr 2025 13:51:56 +1100 (AEDT) Message-ID: <3ebd280e6697790da55f88a5e9e87b4cab407253.camel@ozlabs.org> Subject: Re: [PATCH v3 00/16] Introduce and use generic parity16/32/64 helper From: Jeremy Kerr To: Yury Norov , Kuan-Wei Chiu Cc: "H. Peter Anvin" , David Laight , Andrew Cooper , Laurent.pinchart@ideasonboard.com, airlied@gmail.com, akpm@linux-foundation.org, alistair@popple.id.au, andrew+netdev@lunn.ch, andrzej.hajda@intel.com, arend.vanspriel@broadcom.com, awalls@md.metrocast.net, bp@alien8.de, bpf@vger.kernel.org, brcm80211-dev-list.pdl@broadcom.com, brcm80211@lists.linux.dev, dave.hansen@linux.intel.com, davem@davemloft.net, dmitry.torokhov@gmail.com, dri-devel@lists.freedesktop.org, eajames@linux.ibm.com, edumazet@google.com, eleanor15x@gmail.com, gregkh@linuxfoundation.org, hverkuil@xs4all.nl, jernej.skrabec@gmail.com, jirislaby@kernel.org, joel@jms.id.au, johannes@sipsolutions.net, jonas@kwiboo.se, jserv@ccns.ncku.edu.tw, kuba@kernel.org, linux-fsi@lists.ozlabs.org, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-mtd@lists.infradead.org, linux-serial@vger.kernel.org, linux-wireless@vger.kernel.org, linux@rasmusvillemoes.dk, louis.peens@corigine.com, maarten.lankhorst@linux.intel.com, mchehab@kernel.org, mingo@redhat.com, miquel.raynal@bootlin.com, mripard@kernel.org, neil.armstrong@linaro.org, netdev@vger.kernel.org, oss-drivers@corigine.com, pabeni@redhat.com, parthiban.veerasooran@microchip.com, rfoss@kernel.org, richard@nod.at, simona@ffwll.ch, tglx@linutronix.de, tzimmermann@suse.de, vigneshr@ti.com, x86@kernel.org Date: Fri, 04 Apr 2025 10:51:55 +0800 In-Reply-To: References: <80771542-476C-493E-858A-D2AF6A355CC1@zytor.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.46.4-2 Precedence: bulk X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Hi Yuri & Kuan-Wei: > Thank you for sharing your opinion on this fixed parity(). Your > arguments may or may not be important, depending on what existing > users actually need. Unfortunately, Kuan-Wei didn't collect > performance numbers and opinions from those proposed users. For the fsi-i2c side: this isn't a performance-critical path, and any reasonable common approach would likely perform better that the current per-bit implementation. Our common targets for this driver would be arm and powerpc64le. In case it's useful as a reference, using the kernel compilers I have to hand, a __builtin_parity() is a library call on the former, and a two-instruction sequence for the latter. Cheers, Jeremy