From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9EBD1C4332F for ; Mon, 19 Dec 2022 17:30:03 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id EC93210E2DE; Mon, 19 Dec 2022 17:30:01 +0000 (UTC) Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9EF1610E2EF for ; Mon, 19 Dec 2022 17:29:53 +0000 (UTC) Received: by mail-wr1-x429.google.com with SMTP id co23so9421102wrb.4 for ; Mon, 19 Dec 2022 09:29:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=ogsAwbaUWO+M6t9gf/sX/LdCCLr65p0PXfVPVyBkEPM=; b=d3dHWGobhSoxVE+jTYt6nhUyYF/5zOsbpLRwVaUodSiZeNkwwAgH9IG7kxZD+wrUym SmldAMoxaaGcCb0LOvqhXFDIcCYLiew2+8TXZALmZ3FNe2PNdKdkMjSdBu+fkWg0oyef XsGJVFlg4fsOVlzSHBiJge9X1NvFnh3mkujxnZPj8L1b42TxBwBUAQf/Kac65zhENiKK 9ZHmSLpjHm+vN8CBmMVI5zWOWJro5Ce1tDDzfH65RnwZtwmy/6yDL69IYSZzlir2kpvQ nSoWPGEPZo3fgqvTELWFQHWsjNnjGNF9tCty9svZ9B32FSaH+3KbeuvHZwIdNYdLCQHZ Rojw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=ogsAwbaUWO+M6t9gf/sX/LdCCLr65p0PXfVPVyBkEPM=; b=mi6ipFVLQMMMakre1DXftsysWUxm5yJdRnjjEz2tHEYdCyQ1diJX+ybgkrJsPpROz9 5owpdtfWh0N9RY5LJdVfah2Bq+h2xUoKFG1C58xrAqjWGsFcfSaDooRltRExZ2qc2yep RaZL8cYXzmS1nc0HXy+C8a5rOJuyPdWIMu2L0IfOAOfQew3lRIOatlkLeZ7aAjt3qH7z jfimy2pcQOgiNvw60dGsQsisv/96XZK5T0uE5GM+KrqrIE9DJvaEEW2s9avL1BY91l4k 5/JdQqh/JLqMi6P8ZNIxcDbUYqRVJsInfeDUsvFIq9CoOGJWJdippKQIVJZHZd5Hl5jc h+GQ== X-Gm-Message-State: ANoB5pnnYR4gAFUq07nI+gPgn/maUpWvqfqeZW7DEBUvIg7kfhHzPqat h45+lfYYzeIkmXdXCzLwyFaAyHsNz2c= X-Google-Smtp-Source: AA0mqf6pVHoaII89RIwzatGeKwCh6XKllLDIzES2x2qnmdgFwt4yHuj1Dy294Pmt7Z5oSSwCrPVznQ== X-Received: by 2002:a5d:4ed0:0:b0:242:4a6f:5f18 with SMTP id s16-20020a5d4ed0000000b002424a6f5f18mr26159950wrv.38.1671470991948; Mon, 19 Dec 2022 09:29:51 -0800 (PST) Received: from localhost.localdomain (89-172-43-12.adsl.net.t-com.hr. [89.172.43.12]) by smtp.googlemail.com with ESMTPSA id x18-20020adfec12000000b00236488f62d6sm10532978wrn.79.2022.12.19.09.29.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Dec 2022 09:29:51 -0800 (PST) From: Sasa Dragic To: intel-gfx@lists.freedesktop.org Date: Mon, 19 Dec 2022 18:29:26 +0100 Message-Id: <20221219172927.9603-1-sasa.dragic@gmail.com> X-Mailer: git-send-email 2.37.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [Intel-gfx] [PATCH 0/1] fix RC6p related regression on Sandy Bridge X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Hi all, RC6p got re-enabled on Sandy Bridge over time, seemingly by accident over time, causing graphical glitches and occasional GPU hangs on my old ThinkPad T420, severity depending on kernel version. It is a known issue, e.g.: https://wiki.ubuntu.com/Kernel/PowerManagementRC6 https://www.yoctoproject.org/pipermail/yocto/2012-June/007164.html It was originally disabled in commit 1c8ecf80fdee ("drm/i915: do not enable RC6p on Sandy Bridge"), and subsequently re-enabled by 13c5a577b342 ("drm/i915/gt: Select the deepest available parking mode for rc6"), which seems to focus only on Ivy Bridge. This patch re-disables RC6p on Sandy Bridge. I don't know if this issue is fixed otherwise, and I just have a faulty hardware, but there are few unresolved Sandy Bridge issues floating on the net, which could be related to this. When disabling RC6p graphics works flawlessly, as it also works on 4.15 kernel without modifications. I didn't want to clutter this mail with too much info, so feel free to ask for details, links or to file bug report if necessary. Thanks, Sasa Sasa Dragic (1): drm/i915: re-disable RC6p on Sandy Bridge drivers/gpu/drm/i915/i915_pci.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) -- 2.37.2