Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751081AbbG0HsO (ORCPT ); Mon, 27 Jul 2015 03:48:14 -0400 Received: from mail-wi0-f182.google.com ([209.85.212.182]:35153 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750789AbbG0HsL (ORCPT ); Mon, 27 Jul 2015 03:48:11 -0400 Date: Mon, 27 Jul 2015 09:50:50 +0200 From: Daniel Vetter To: Dan Williams Cc: tglx@linutronix.de, mingo@kernel.org, hpa@zytor.com, linux-arch@vger.kernel.org, toshi.kani@hp.com, linux-nvdimm@ml01.01.org, David Airlie , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Daniel Vetter , rmk+kernel@arm.linux.org.uk, hch@lst.de, linux-arm-kernel@lists.infradead.org Subject: Re: [Intel-gfx] [PATCH v2 12/25] i915: switch from acpi_os_ioremap to ioremap Message-ID: <20150727075050.GK16722@phenom.ffwll.local> Mail-Followup-To: Dan Williams , tglx@linutronix.de, mingo@kernel.org, hpa@zytor.com, linux-arch@vger.kernel.org, toshi.kani@hp.com, linux-nvdimm@lists.01.org, David Airlie , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Daniel Vetter , rmk+kernel@arm.linux.org.uk, hch@lst.de, linux-arm-kernel@lists.infradead.org References: <20150725023649.8664.59145.stgit@dwillia2-desk3.amr.corp.intel.com> <20150725023904.8664.84461.stgit@dwillia2-desk3.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150725023904.8664.84461.stgit@dwillia2-desk3.amr.corp.intel.com> X-Operating-System: Linux phenom 4.2.0-rc1+ User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1743 Lines: 43 On Fri, Jul 24, 2015 at 10:39:04PM -0400, Dan Williams wrote: > acpi_os_ioremap uses cached mappings, however it appears that i915 > wants to read dynamic platform state. Switch to ioremap() to prevent it > reading stale state from cache. > > Cc: Daniel Vetter > Cc: Jani Nikula > Cc: intel-gfx@lists.freedesktop.org > Cc: David Airlie > Cc: dri-devel@lists.freedesktop.org > Signed-off-by: Dan Williams > --- > drivers/gpu/drm/i915/intel_opregion.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c > index 481337436f72..16ba7c67410d 100644 > --- a/drivers/gpu/drm/i915/intel_opregion.c > +++ b/drivers/gpu/drm/i915/intel_opregion.c > @@ -863,7 +863,7 @@ int intel_opregion_setup(struct drm_device *dev) > INIT_WORK(&opregion->asle_work, asle_work); > #endif > > - base = acpi_os_ioremap(asls, OPREGION_SIZE); > + base = ioremap(asls, OPREGION_SIZE); OpRegion is cached memory shared with the firmware afaik, we probably want a memremap here and switch away from the ioread/write stuff. We have a similar confusion going on for the vbt parsing (which on anything but really old machines is also just normal memory). Same holds for gma500, which is just a copy of i915 for some special platforms. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/