Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752527Ab0K0Nho (ORCPT ); Sat, 27 Nov 2010 08:37:44 -0500 Received: from fmmailgate03.web.de ([217.72.192.234]:59117 "EHLO fmmailgate03.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752196Ab0K0Nhm (ORCPT ); Sat, 27 Nov 2010 08:37:42 -0500 To: Michal Januszewski Subject: [PATCH] uvesafb,vesafb: create write-combining or write-back PAT entries From: Thomas Schlichter Cc: linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org Date: Sat, 27 Nov 2010 14:37:37 +0100 MIME-Version: 1.0 Content-Type: Multipart/Mixed; boundary="Boundary-00=_imQ8M+A3xhCkXAK" Message-Id: <201011271437.38126.thomas.schlichter@web.de> X-Provags-ID: V01U2FsdGVkX18mD65AlhIqJHk91eC5Jr1tWijwWvT+7EKAxIs0 OxO4VLg72KlVBqCg0pGpa5uO0c754+ydP7wnHjCyGnmohW7r5g OKaa0cOhGoT59uS+fsRg== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9747 Lines: 286 --Boundary-00=_imQ8M+A3xhCkXAK Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi, with an PAT-enabled kernel (tested with 2.6.35, but the problem is still present in current -tip), when using uvesafb or vesafb, these drivers will create uncached-minus PAT entries for the framebuffer memory because they use ioremap() (not the *_cached or *_wc variants). When the framebuffer memory intersects with the video RAM used by Xorg, the complete video RAM will be mapped uncached-minus what results in a serve performance penalty. Here are the correct MTRR entries created by uvesafb: schlicht@netbook:~$ cat /proc/mtrr reg00: base=0x000000000 ( 0MB), size= 2048MB, count=1: write-back reg01: base=0x06ff00000 ( 1791MB), size= 1MB, count=1: uncachable reg02: base=0x070000000 ( 1792MB), size= 256MB, count=1: uncachable reg03: base=0x0d0000000 ( 3328MB), size= 16MB, count=1: write-combining And here are the problematic PAT entries: schlicht@netbook:~$ sudo cat /sys/kernel/debug/x86/pat_memtype_list PAT memtype list: write-back @ 0x0-0x1000 uncached-minus @ 0x6fedd000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee3000-0x6fee4000 uncached-minus @ 0x6fee3000-0x6fee4000 uncached-minus @ 0x6fee3000-0x6fee4000 uncached-minus @ 0xd0000000-0xe0000000 <-- created by xserver-xorg uncached-minus @ 0xd0000000-0xd1194000 <-- created by uvesafb uncached-minus @ 0xf4000000-0xf4009000 uncached-minus @ 0xf4200000-0xf4400000 uncached-minus @ 0xf5000000-0xf5010000 uncached-minus @ 0xf5100000-0xf5104000 uncached-minus @ 0xf5400000-0xf5404000 uncached-minus @ 0xf5404000-0xf5405000 uncached-minus @ 0xf5404000-0xf5405000 uncached-minus @ 0xfed00000-0xfed01000 Therefore I created the attached patch for uvesafb which uses ioremap_wc() to create the correct PAT entries, as shown below: schlicht@netbook:~$ sudo cat /sys/kernel/debug/x86/pat_memtype_list PAT memtype list: write-back @ 0x0-0x1000 uncached-minus @ 0x6fedd000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee2000-0x6fee3000 uncached-minus @ 0x6fee3000-0x6fee4000 uncached-minus @ 0x6fee3000-0x6fee4000 uncached-minus @ 0x6fee3000-0x6fee4000 write-combining @ 0xd0000000-0xe0000000 write-combining @ 0xd0000000-0xd1194000 uncached-minus @ 0xf4000000-0xf4009000 uncached-minus @ 0xf4200000-0xf4400000 uncached-minus @ 0xf5000000-0xf5010000 uncached-minus @ 0xf5100000-0xf5104000 uncached-minus @ 0xf5400000-0xf5404000 uncached-minus @ 0xf5404000-0xf5405000 uncached-minus @ 0xf5404000-0xf5405000 uncached-minus @ 0xfed00000-0xfed01000 This results in a performance gain, objectively measurable with e.g. x11perf -comppixwin10 -comppixwin100 -comppixwin500: 1: x11perf_xaa.log 2: x11perf_xaa_patched.log 1 2 Operation -------- ----------------- ----------------- 124000.0 202000.0 ( 1.63) Composite 10x10 from pixmap to window 3340.0 24400.0 ( 7.31) Composite 100x100 from pixmap to window 131.0 1150.0 ( 8.78) Composite 500x500 from pixmap to window You can see the serve performance gain when composing larger pixmaps to window. Please consider applying the attached patches for uvesafb and vesafb. These patches (for -tip) replace the ioremap() function with the variants matching the mtrr-parameter. To create "write-back" PAT entries, the ioremap_cache() function must be called after creating the MTRR entries, and the ioremap_cache() region must completely fit into the MTRR region, this is why the MTRR region size is now rounded up to the next power-of-two. Signed-off-by: Thomas Schlichter Thank you very much! Kind regards, Thomas --Boundary-00=_imQ8M+A3xhCkXAK Content-Type: text/x-patch; charset="us-ascii"; name="vesafb.diff" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="vesafb.diff" diff --git a/drivers/video/vesafb.c b/drivers/video/vesafb.c index 6a069d0..a99bbe8 100644 --- a/drivers/video/vesafb.c +++ b/drivers/video/vesafb.c @@ -303,19 +303,6 @@ static int __init vesafb_probe(struct platform_device *dev) info->apertures->ranges[0].base = screen_info.lfb_base; info->apertures->ranges[0].size = size_total; - info->screen_base = ioremap(vesafb_fix.smem_start, vesafb_fix.smem_len); - if (!info->screen_base) { - printk(KERN_ERR - "vesafb: abort, cannot ioremap video memory 0x%x @ 0x%lx\n", - vesafb_fix.smem_len, vesafb_fix.smem_start); - err = -EIO; - goto err; - } - - printk(KERN_INFO "vesafb: framebuffer at 0x%lx, mapped to 0x%p, " - "using %dk, total %dk\n", - vesafb_fix.smem_start, info->screen_base, - size_remap/1024, size_total/1024); printk(KERN_INFO "vesafb: mode is %dx%dx%d, linelength=%d, pages=%d\n", vesafb_defined.xres, vesafb_defined.yres, vesafb_defined.bits_per_pixel, vesafb_fix.line_length, screen_info.pages); @@ -438,8 +425,7 @@ static int __init vesafb_probe(struct platform_device *dev) int rc; /* Find the largest power-of-two */ - while (temp_size & (temp_size - 1)) - temp_size &= (temp_size - 1); + temp_size = roundup_pow_of_two(temp_size); /* Try and find a power of two to add */ do { @@ -451,6 +437,34 @@ static int __init vesafb_probe(struct platform_device *dev) } #endif + switch (mtrr) { + case 1: /* uncachable */ + info->screen_base = ioremap_nocache(vesafb_fix.smem_start, vesafb_fix.smem_len); + break; + case 2: /* write-back */ + info->screen_base = ioremap_cache(vesafb_fix.smem_start, vesafb_fix.smem_len); + break; + case 3: /* write-combining */ + info->screen_base = ioremap_wc(vesafb_fix.smem_start, vesafb_fix.smem_len); + break; + case 4: /* write-through */ + default: + info->screen_base = ioremap(vesafb_fix.smem_start, vesafb_fix.smem_len); + break; + } + if (!info->screen_base) { + printk(KERN_ERR + "vesafb: abort, cannot ioremap video memory 0x%x @ 0x%lx\n", + vesafb_fix.smem_len, vesafb_fix.smem_start); + err = -EIO; + goto err; + } + + printk(KERN_INFO "vesafb: framebuffer at 0x%lx, mapped to 0x%p, " + "using %dk, total %dk\n", + vesafb_fix.smem_start, info->screen_base, + size_remap/1024, size_total/1024); + info->fbops = &vesafb_ops; info->var = vesafb_defined; info->fix = vesafb_fix; --Boundary-00=_imQ8M+A3xhCkXAK Content-Type: text/x-patch; charset="us-ascii"; name="uvesafb.diff" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="uvesafb.diff" diff --git a/drivers/video/uvesafb.c b/drivers/video/uvesafb.c index 52ec095..5a34bc8 100644 --- a/drivers/video/uvesafb.c +++ b/drivers/video/uvesafb.c @@ -1552,8 +1552,7 @@ static void __devinit uvesafb_init_mtrr(struct fb_info *info) int rc; /* Find the largest power-of-two */ - while (temp_size & (temp_size - 1)) - temp_size &= (temp_size - 1); + temp_size = roundup_pow_of_two(temp_size); /* Try and find a power of two to add */ do { @@ -1736,15 +1735,37 @@ static int __devinit uvesafb_probe(struct platform_device *dev) uvesafb_init_info(info, mode); + if (!request_region(0x3c0, 32, "uvesafb")) { + printk(KERN_ERR "uvesafb: request region 0x3c0-0x3e0 failed\n"); + err = -EIO; + goto out_mode; + } + if (!request_mem_region(info->fix.smem_start, info->fix.smem_len, "uvesafb")) { printk(KERN_ERR "uvesafb: cannot reserve video memory at " "0x%lx\n", info->fix.smem_start); err = -EIO; - goto out_mode; + goto out_reg; } - info->screen_base = ioremap(info->fix.smem_start, info->fix.smem_len); + uvesafb_init_mtrr(info); + + switch (mtrr) { + case 1: /* uncachable */ + info->screen_base = ioremap_nocache(info->fix.smem_start, info->fix.smem_len); + break; + case 2: /* write-back */ + info->screen_base = ioremap_cache(info->fix.smem_start, info->fix.smem_len); + break; + case 3: /* write-combining */ + info->screen_base = ioremap_wc(info->fix.smem_start, info->fix.smem_len); + break; + case 4: /* write-through */ + default: + info->screen_base = ioremap(info->fix.smem_start, info->fix.smem_len); + break; + } if (!info->screen_base) { printk(KERN_ERR @@ -1755,20 +1776,13 @@ static int __devinit uvesafb_probe(struct platform_device *dev) goto out_mem; } - if (!request_region(0x3c0, 32, "uvesafb")) { - printk(KERN_ERR "uvesafb: request region 0x3c0-0x3e0 failed\n"); - err = -EIO; - goto out_unmap; - } - - uvesafb_init_mtrr(info); platform_set_drvdata(dev, info); if (register_framebuffer(info) < 0) { printk(KERN_ERR "uvesafb: failed to register framebuffer device\n"); err = -EINVAL; - goto out_reg; + goto out_unmap; } printk(KERN_INFO "uvesafb: framebuffer at 0x%lx, mapped to 0x%p, " @@ -1785,12 +1799,12 @@ static int __devinit uvesafb_probe(struct platform_device *dev) return 0; -out_reg: - release_region(0x3c0, 32); out_unmap: iounmap(info->screen_base); out_mem: release_mem_region(info->fix.smem_start, info->fix.smem_len); +out_reg: + release_region(0x3c0, 32); out_mode: if (!list_empty(&info->modelist)) fb_destroy_modelist(&info->modelist); --Boundary-00=_imQ8M+A3xhCkXAK-- -- 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/