From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Luis R. Rodriguez" Subject: Re: [PATCH v1 23/47] staging: xgifb: use arch_phys_wc_add() and ioremap_wc() Date: Thu, 30 Apr 2015 10:40:08 -0700 Message-ID: References: <1426893517-2511-1-git-send-email-mcgrof@do-not-panic.com> <1426893517-2511-24-git-send-email-mcgrof@do-not-panic.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YnsRt-0000Ke-HE for xen-devel@lists.xenproject.org; Thu, 30 Apr 2015 17:40:33 +0000 Received: by igbhj9 with SMTP id hj9so20206392igb.1 for ; Thu, 30 Apr 2015 10:40:28 -0700 (PDT) In-Reply-To: <1426893517-2511-24-git-send-email-mcgrof@do-not-panic.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andy Lutomirski , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Juergen Gross , Jan Beulich , Borislav Petkov , Suresh Siddha , venkatesh.pallipadi@intel.com, Dave Airlie Cc: linux-fbdev , Antonino Daplas , Daniel Vetter , "Luis R. Rodriguez" , X86 ML , "linux-kernel@vger.kernel.org" , Tomi Valkeinen , xen-devel@lists.xenproject.org, Ingo Molnar , Jean-Christophe Plagniol-Villard List-Id: xen-devel@lists.xenproject.org On Fri, Mar 20, 2015 at 4:18 PM, Luis R. Rodriguez wrote: > The same area used for ioremap() is used for the MTRR area. > Convert the driver from using the x86 specific MTRR code to > the architecture agnostic arch_phys_wc_add(). arch_phys_wc_add() > will avoid MTRR if write-combining is available, in order to > take advantage of that also ensure the ioremap'd area is requested > as write-combining. > > There are a few motivations for this: > > a) Take advantage of PAT when available > > b) Help bury MTRR code away, MTRR is architecture specific and on > x86 its replaced by PAT > > c) Help with the goal of eventually using _PAGE_CACHE_UC over > _PAGE_CACHE_UC_MINUS on x86 on ioremap_nocache() (de33c442e) > > The conversion done is expressed by the following Coccinelle > SmPL patch, it additionally required manual intervention to > address all the #ifdery and removal of redundant things which > arch_phys_wc_add() already addresses such as verbose message > about when MTRR fails and doing nothing when we didn't get > an MTRR. > > @ mtrr_found @ > expression index, base, size; > @@ > > -index = mtrr_add(base, size, MTRR_TYPE_WRCOMB, 1); > +index = arch_phys_wc_add(base, size); > > @ mtrr_rm depends on mtrr_found @ > expression mtrr_found.index, mtrr_found.base, mtrr_found.size; > @@ > > -mtrr_del(index, base, size); > +arch_phys_wc_del(index); > > @ mtrr_rm_zero_arg depends on mtrr_found @ > expression mtrr_found.index; > @@ > > -mtrr_del(index, 0, 0); > +arch_phys_wc_del(index); > > @ mtrr_rm_fb_info depends on mtrr_found @ > struct fb_info *info; > expression mtrr_found.index; > @@ > > -mtrr_del(index, info->fix.smem_start, info->fix.smem_len); > +arch_phys_wc_del(index); > > @ ioremap_replace_nocache depends on mtrr_found @ > struct fb_info *info; > expression base, size; > @@ > > -info->screen_base = ioremap_nocache(base, size); > +info->screen_base = ioremap_wc(base, size); > > @ ioremap_replace_default depends on mtrr_found @ > struct fb_info *info; > expression base, size; > @@ > > -info->screen_base = ioremap(base, size); > +info->screen_base = ioremap_wc(base, size); > > Generated-by: Coccinelle SmPL > Cc: Suresh Siddha > Cc: Venkatesh Pallipadi > Cc: Ingo Molnar > Cc: Thomas Gleixner > Cc: Juergen Gross > Cc: Daniel Vetter > Cc: Andy Lutomirski > Cc: Dave Airlie > Cc: Antonino Daplas > Cc: Jean-Christophe Plagniol-Villard > Cc: Tomi Valkeinen > Cc: linux-fbdev@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Luis R. Rodriguez Hey folks, can this be considered to be merged. Thanks, Luis