From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754966Ab3BCO6N (ORCPT ); Sun, 3 Feb 2013 09:58:13 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:34528 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753072Ab3BCO5z (ORCPT ); Sun, 3 Feb 2013 09:57:55 -0500 Message-Id: <20130203144653.695109352@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Sun, 03 Feb 2013 15:48:33 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: akpm@linux-foundation.org, Jesse Barnes , "H. Peter Anvin" Subject: [ 109/128] x86/Sandy Bridge: reserve pages when integrated graphics is present In-Reply-To: <20130203144644.035172954@decadent.org.uk> X-SA-Exim-Connect-IP: 151.216.67.5 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jesse Barnes commit a9acc5365dbda29f7be2884efb63771dc24bd815 upstream. SNB graphics devices have a bug that prevent them from accessing certain memory ranges, namely anything below 1M and in the pages listed in the table. So reserve those at boot if set detect a SNB gfx device on the CPU to avoid GPU hangs. Stephane Marchesin had a similar patch to the page allocator awhile back, but rather than reserving pages up front, it leaked them at allocation time. [ hpa: made a number of stylistic changes, marked arrays as static const, and made less verbose; use "memblock=debug" for full verbosity. ] Signed-off-by: Jesse Barnes Signed-off-by: H. Peter Anvin Signed-off-by: Ben Hutchings --- arch/x86/kernel/setup.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -631,6 +631,81 @@ static __init void reserve_ibft_region(v static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10; +static bool __init snb_gfx_workaround_needed(void) +{ + int i; + u16 vendor, devid; + static const u16 snb_ids[] = { + 0x0102, + 0x0112, + 0x0122, + 0x0106, + 0x0116, + 0x0126, + 0x010a, + }; + + /* Assume no if something weird is going on with PCI */ + if (!early_pci_allowed()) + return false; + + vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID); + if (vendor != 0x8086) + return false; + + devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID); + for (i = 0; i < ARRAY_SIZE(snb_ids); i++) + if (devid == snb_ids[i]) + return true; + + return false; +} + +/* + * Sandy Bridge graphics has trouble with certain ranges, exclude + * them from allocation. + */ +static void __init trim_snb_memory(void) +{ + static const unsigned long bad_pages[] = { + 0x20050000, + 0x20110000, + 0x20130000, + 0x20138000, + 0x40004000, + }; + int i; + + if (!snb_gfx_workaround_needed()) + return; + + printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n"); + + /* + * Reserve all memory below the 1 MB mark that has not + * already been reserved. + */ + memblock_reserve(0, 1<<20); + + for (i = 0; i < ARRAY_SIZE(bad_pages); i++) { + if (memblock_reserve(bad_pages[i], PAGE_SIZE)) + printk(KERN_WARNING "failed to reserve 0x%08lx\n", + bad_pages[i]); + } +} + +/* + * Here we put platform-specific memory range workarounds, i.e. + * memory known to be corrupt or otherwise in need to be reserved on + * specific platforms. + * + * If this gets used more widely it could use a real dispatch mechanism. + */ +static void __init trim_platform_memory_ranges(void) +{ + trim_snb_memory(); +} + static void __init trim_bios_range(void) { /* @@ -651,6 +726,7 @@ static void __init trim_bios_range(void) * take them out. */ e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1); + sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); } @@ -930,6 +1006,8 @@ void __init setup_arch(char **cmdline_p) setup_trampolines(); + trim_platform_memory_ranges(); + init_gbpages(); /* max_pfn_mapped is updated here */