Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934148AbbDVHfI (ORCPT ); Wed, 22 Apr 2015 03:35:08 -0400 Received: from eusmtp01.atmel.com ([212.144.249.242]:18629 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933223AbbDVHfE (ORCPT ); Wed, 22 Apr 2015 03:35:04 -0400 Message-ID: <55374EEA.1050909@atmel.com> Date: Wed, 22 Apr 2015 09:34:02 +0200 From: Nicolas Ferre Organization: atmel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: "Luis R. Rodriguez" , , CC: , , , "Luis R. Rodriguez" , Suresh Siddha , Ingo Molnar , Thomas Gleixner , Juergen Gross , Daniel Vetter , Dave Airlie , Antonino Daplas , Subject: Re: [PATCH v3 16/17] video: fbdev: atmel_lcdfb: use ioremap_wc() for framebuffer References: <1429647398-16983-1-git-send-email-mcgrof@do-not-panic.com> <1429647398-16983-17-git-send-email-mcgrof@do-not-panic.com> In-Reply-To: <1429647398-16983-17-git-send-email-mcgrof@do-not-panic.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit X-Originating-IP: [10.161.30.18] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2358 Lines: 68 Le 21/04/2015 22:16, Luis R. Rodriguez a ?crit : > From: "Luis R. Rodriguez" > > The driver doesn't use mtrr_add() or arch_phys_wc_add() but > since we know the framebuffer is isolated already on an > ioremap() we can take advantage of write combining for > performance where possible. > > In this case there are a few motivations for this: > > a) Take advantage of PAT when available > > b) 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()") > > Cc: Nicolas Ferre Seems okay: Acked-by: Nicolas Ferre Thanks for having taking care of atmel_lcdfb driver. Bye, > 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: linux-fbdev@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Luis R. Rodriguez > --- > drivers/video/fbdev/atmel_lcdfb.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/video/fbdev/atmel_lcdfb.c b/drivers/video/fbdev/atmel_lcdfb.c > index 94a8d04..abadc49 100644 > --- a/drivers/video/fbdev/atmel_lcdfb.c > +++ b/drivers/video/fbdev/atmel_lcdfb.c > @@ -1266,7 +1266,8 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev) > goto stop_clk; > } > > - info->screen_base = ioremap(info->fix.smem_start, info->fix.smem_len); > + info->screen_base = ioremap_wc(info->fix.smem_start, > + info->fix.smem_len); > if (!info->screen_base) { > ret = -ENOMEM; > goto release_intmem; > -- Nicolas Ferre -- 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/