From patchwork Mon Sep 18 23:12:52 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 9957753 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id ABCB460208 for ; Mon, 18 Sep 2017 23:13:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9EFD228CB4 for ; Mon, 18 Sep 2017 23:13:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9368228DC4; Mon, 18 Sep 2017 23:13:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 22A7828CB4 for ; Mon, 18 Sep 2017 23:13:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750948AbdIRXNJ (ORCPT ); Mon, 18 Sep 2017 19:13:09 -0400 Received: from ale.deltatee.com ([207.54.116.67]:53968 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750747AbdIRXNG (ORCPT ); Mon, 18 Sep 2017 19:13:06 -0400 Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1du5Ds-00048G-OX; Mon, 18 Sep 2017 17:13:05 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.89) (envelope-from ) id 1du5Dr-0000pf-9N; Mon, 18 Sep 2017 17:13:03 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-ntb@googlegroups.com, linux-crypto@vger.kernel.org Cc: Arnd Bergmann , Greg Kroah-Hartman , Andy Shevchenko , =?UTF-8?q?Horia=20Geant=C4=83?= , Logan Gunthorpe , Jyri Sarha , Tomi Valkeinen , David Airlie Date: Mon, 18 Sep 2017 17:12:52 -0600 Message-Id: <20170918231258.3151-2-logang@deltatee.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170918231258.3151-1-logang@deltatee.com> References: <20170918231258.3151-1-logang@deltatee.com> X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-ntb@googlegroups.com, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-crypto@vger.kernel.org, arnd@arndb.de, gregkh@linuxfoundation.org, andy.shevchenko@gmail.com, horia.geanta@nxp.com, logang@deltatee.com, jsarha@ti.com, tomi.valkeinen@ti.com, airlied@linux.ie X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v8 1/7] drm/tilcdc: ensure nonatomic iowrite64 is not used X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add a check to ensure iowrite64 is only used if it is atomic. It was decided in [1] that the tilcdc driver should not be using an atomic operation (so it was left out of this patchset). However, it turns out that through the drm code, a nonatomic header is actually included: include/linux/io-64-nonatomic-lo-hi.h is included from include/drm/drm_os_linux.h:9:0, from include/drm/drmP.h:74, from include/drm/drm_modeset_helper.h:26, from include/drm/drm_atomic_helper.h:33, from drivers/gpu/drm/tilcdc/tilcdc_crtc.c:19: And thus, without this change, this patchset would inadvertantly change the behaviour of the tilcdc driver. [1] lkml.kernel.org/r/CAK8P3a2HhO_zCnsTzq7hmWSz5La5Thu19FWZpun16iMnyyNreQ@mail.gmail.com Signed-off-by: Logan Gunthorpe Reviewed-by: Andy Shevchenko Cc: Jyri Sarha Cc: Arnd Bergmann Cc: Tomi Valkeinen Cc: David Airlie --- drivers/gpu/drm/tilcdc/tilcdc_regs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/tilcdc/tilcdc_regs.h b/drivers/gpu/drm/tilcdc/tilcdc_regs.h index 9d528c0a67a4..5048ebb86835 100644 --- a/drivers/gpu/drm/tilcdc/tilcdc_regs.h +++ b/drivers/gpu/drm/tilcdc/tilcdc_regs.h @@ -133,7 +133,7 @@ static inline void tilcdc_write64(struct drm_device *dev, u32 reg, u64 data) struct tilcdc_drm_private *priv = dev->dev_private; volatile void __iomem *addr = priv->mmio + reg; -#ifdef iowrite64 +#if defined(iowrite64) && !defined(iowrite64_is_nonatomic) iowrite64(data, addr); #else __iowmb();