Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755377AbbHXTOC (ORCPT ); Mon, 24 Aug 2015 15:14:02 -0400 Received: from mail-pa0-f45.google.com ([209.85.220.45]:35463 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751179AbbHXTN5 (ORCPT ); Mon, 24 Aug 2015 15:13:57 -0400 From: "Luis R. Rodriguez" To: mingo@kernel.org Cc: bp@suse.de, bhelgaas@google.com, tomi.valkeinen@ti.com, airlied@linux.ie, linux-fbdev@vger.kernel.org, luto@amacapital.net, vinod.koul@intel.com, dan.j.williams@intel.com, toshi.kani@hp.com, benh@kernel.crashing.org, mst@redhat.com, akpm@linux-foundation.org, daniel.vetter@ffwll.ch, konrad.wilk@oracle.com, x86@kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, xen-devel@lists.xensource.com, "Luis R. Rodriguez" , Antonino Daplas , Arnd Bergmann , Dave Airlie , Geert Uytterhoeven , "H. Peter Anvin" , Jean-Christophe Plagniol-Villard , Juergen Gross , Laurent Pinchart , Rob Clark , Suresh Siddha , Thomas Gleixner Subject: [PATCH v4 04/11] drivers/video/fbdev/gxt4500: Use pci_ioremap_wc_bar() to map framebuffer Date: Mon, 24 Aug 2015 12:13:26 -0700 Message-Id: <1440443613-13696-5-git-send-email-mcgrof@do-not-panic.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1440443613-13696-1-git-send-email-mcgrof@do-not-panic.com> References: <1440443613-13696-1-git-send-email-mcgrof@do-not-panic.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2555 Lines: 66 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()"). Signed-off-by: Luis R. Rodriguez Acked-by: Tomi Valkeinen Cc: Andrew Morton Cc: Andy Lutomirski Cc: Antonino Daplas Cc: Arnd Bergmann Cc: benh@kernel.crashing.org Cc: bhelgaas@google.com Cc: Daniel Vetter Cc: Dave Airlie Cc: Geert Uytterhoeven Cc: H. Peter Anvin Cc: Ingo Molnar Cc: Jean-Christophe Plagniol-Villard Cc: Juergen Gross Cc: Laurent Pinchart Cc: linux-fbdev@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: mst@redhat.com Cc: Rob Clark Cc: Suresh Siddha Cc: Thomas Gleixner Cc: toshi.kani@hp.com Link: http://lkml.kernel.org/r/1435195342-26879-5-git-send-email-mcgrof@do-not-panic.com Signed-off-by: Borislav Petkov --- drivers/video/fbdev/gxt4500.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/fbdev/gxt4500.c b/drivers/video/fbdev/gxt4500.c index 135d78a02588..f19133a80e8c 100644 --- a/drivers/video/fbdev/gxt4500.c +++ b/drivers/video/fbdev/gxt4500.c @@ -662,7 +662,7 @@ static int gxt4500_probe(struct pci_dev *pdev, const struct pci_device_id *ent) info->fix.smem_start = fb_phys; info->fix.smem_len = pci_resource_len(pdev, 1); - info->screen_base = pci_ioremap_bar(pdev, 1); + info->screen_base = pci_ioremap_wc_bar(pdev, 1); if (!info->screen_base) { dev_err(&pdev->dev, "gxt4500: cannot map framebuffer\n"); goto err_unmap_regs; -- 2.4.3 -- 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/