From 1e43a20396ee34a6b0305fc155cb59af13a89435 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Tue, 21 Apr 2015 13:16:37 -0700 Subject: [PATCH] video: fbdev: atmel_lcdfb: use ioremap_wc() for framebuffer 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 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 Acked-by: Nicolas Ferre Reviewed-by: Dave Airlie Signed-off-by: Tomi Valkeinen --- 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 94a8d04e60f9..abadc490fa1f 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; -- 2.20.1