Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751741AbbECTZX (ORCPT ); Sun, 3 May 2015 15:25:23 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:52424 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750918AbbECTZP (ORCPT ); Sun, 3 May 2015 15:25:15 -0400 Date: Sun, 3 May 2015 21:24:59 +0200 From: Greg KH To: "Luis R. Rodriguez" Cc: sudipm.mukherjee@gmail.com, teddy.wang@siliconmotion.com, devel@driverdev.osuosl.org, luto@amacapital.net, cocci@systeme.lip6.fr, "Luis R. Rodriguez" , Suresh Siddha , Ingo Molnar , Thomas Gleixner , Juergen Gross , Daniel Vetter , Dave Airlie , Antonino Daplas , Jean-Christophe Plagniol-Villard , Tomi Valkeinen , linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] staging: sm750fb: use arch_phys_wc_add() and ioremap_wc() Message-ID: <20150503192459.GA19486@kroah.com> References: <1429647123-16777-1-git-send-email-mcgrof@do-not-panic.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1429647123-16777-1-git-send-email-mcgrof@do-not-panic.com> 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: 3641 Lines: 105 On Tue, Apr 21, 2015 at 01:12:03PM -0700, Luis R. Rodriguez wrote: > From: "Luis R. Rodriguez" > > 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() (see commit > de33c442e titled "x86 PAT: fix performance drop for glx, > use UC minus for ioremap(), ioremap_nocache() and > pci_mmap_page_range()") > > 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: Sudip Mukherjee > Cc: Teddy Wang > Cc: Greg Kroah-Hartman > Cc: Suresh Siddha > 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: devel@driverdev.osuosl.org > Cc: linux-fbdev@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Luis R. Rodriguez > --- > drivers/staging/sm750fb/sm750.c | 36 ++++-------------------------------- > drivers/staging/sm750fb/sm750.h | 3 --- > drivers/staging/sm750fb/sm750_hw.c | 3 +-- > 3 files changed, 5 insertions(+), 37 deletions(-) This doesn't apply to my staging-next branch :( -- 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/