From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D46B9C433E1 for ; Fri, 22 May 2020 15:22:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B5B632072C for ; Fri, 22 May 2020 15:22:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590160969; bh=MMSmt+qYR9drLnxHce8Ry8LIx3FSk/xxE5Ta8UzagXs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=pT/zJ7z932dsd1fkVIwSjth/QcEfSq9AbKlgY6xRhETu9hLFqA9RgUJpbOB+Gz/Vn vrK+Xm81xO5AgU41tB0F0O+DgKWh57XbZbNF6g6ayaSz3YRBAXTvPkVqF36YPkG/5q w+xf7CAWcgP8FhXgfBUzny+KqSQWc9yu57+b31rw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730312AbgEVPWp (ORCPT ); Fri, 22 May 2020 11:22:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:44148 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729931AbgEVPWo (ORCPT ); Fri, 22 May 2020 11:22:44 -0400 Received: from localhost (fw-tnat.cambridge.arm.com [217.140.96.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5A6712054F; Fri, 22 May 2020 15:22:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590160963; bh=MMSmt+qYR9drLnxHce8Ry8LIx3FSk/xxE5Ta8UzagXs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=c8g53iNeyEdE0ohX81JBwKeBzrW0/TjYPXRhZSTk7ZHd7SkhtyxYzOBTXh69PaKF+ QCt1TeKaDnRF/Lm5Og6NPRiq0Rdk5Wb7q2QSbzUcKcX2NK7lYEL/pccNoxvrzOoX45 /P+hqn92r16BozLUp1h9Egi63kCkKFXfr2lPPFYw= Date: Fri, 22 May 2020 16:22:41 +0100 From: Mark Brown To: Serge Semin Cc: Andy Shevchenko , Serge Semin , Linus Walleij , Vinod Koul , Feng Tang , Grant Likely , Alan Cox , Georgy Vlasov , Ramil Zaripov , Alexey Malahov , Thomas Bogendoerfer , Paul Burton , Ralf Baechle , Arnd Bergmann , Rob Herring , linux-mips@vger.kernel.org, devicetree@vger.kernel.org, Wan Ahmad Zainie , Thomas Gleixner , Jarkko Nikula , "wuxu.wu" , Clement Leger , Linus Walleij , linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 01/16] spi: dw: Add Tx/Rx finish wait methods to the MID DMA Message-ID: <20200522152241.GK5801@sirena.org.uk> References: <20200522115235.rt3ay7lveimrgooa@mobilestation> <20200522121221.GA1634618@smile.fi.intel.com> <20200522121820.GG5801@sirena.org.uk> <20200522123427.GD1634618@smile.fi.intel.com> <20200522124406.co7gmteojfsooerc@mobilestation> <20200522131013.GH5801@sirena.org.uk> <20200522132742.taf2ixfjpyd5u3dt@mobilestation> <20200522140025.bmd6bhpjjk5msvsm@mobilestation> <20200522143639.GG1634618@smile.fi.intel.com> <20200522144542.brhibh453wid2d6v@mobilestation> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="BFVE2HhgxTpCzM8t" Content-Disposition: inline In-Reply-To: <20200522144542.brhibh453wid2d6v@mobilestation> X-Cookie: C for yourself. User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org --BFVE2HhgxTpCzM8t Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Fri, May 22, 2020 at 05:45:42PM +0300, Serge Semin wrote: > On Fri, May 22, 2020 at 05:36:39PM +0300, Andy Shevchenko wrote: > > My point is: let's warn and see if anybody comes with a bug report. We will > > solve an issue when it appears. > In my environment the stack trace happened (strictly speaking it has been a > BUG() invoked due to the sleep_range() called within the tasklet) when SPI bus > had been enabled to work with !8MHz! clock. It's quite normal bus speed. > So we'll get the bug report pretty soon.) Right, that definitely needs to be fixed then - 8MHz is indeed a totally normal clock rate for SPI so people will hit it. I guess if there's a noticable performance hit to defer to thread then we could implement both and look at how long the delay is going to be to decide which to use, that's annoyingly complicated though so if the overhead is small enough we could just not bother. --BFVE2HhgxTpCzM8t Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl7H7kAACgkQJNaLcl1U h9B6Kgf/QkMYmBdVYxKlZ5TKL+hL0E4I7igNofk1QV1k9b5qAbVEpBw0bQOyDb0c XGkJFC+Ow7XjhFaGyTc7Ay4BXbUQdO3+Oi+OG11yN6x0YdRBcds5qJPEj2uuWQZV 1+qhlWYx8xJHNzuMo3MYi3ylIpi7jFe8Wrk2p9EBk5RvNP0LUv1nfRaPKiEToZm0 w6R+gPOW8mFWniwmXgd0fUiDWsaStPuYl8Nf2h1yqgrwUW/1/xH9Wey+1ImpOxqU Jxy4BMrcYvZpxRvOlDt3NmgZhavC7/COFrnnlEOjAaN4B0iFhHPCElbQhj8AkQ/M GmH3wFqGIB8Lydgs9cBhaouUI0sVrA== =Bjdn -----END PGP SIGNATURE----- --BFVE2HhgxTpCzM8t--