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 X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46A7EC43381 for ; Sat, 16 Mar 2019 22:25:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 125BB218FE for ; Sat, 16 Mar 2019 22:25:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=tomli.me header.i=@tomli.me header.b="Nj6NsDsp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727227AbfCPWZe (ORCPT ); Sat, 16 Mar 2019 18:25:34 -0400 Received: from tomli.me ([153.92.126.73]:56126 "EHLO tomli.me" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726418AbfCPWZc (ORCPT ); Sat, 16 Mar 2019 18:25:32 -0400 Received: from tomli.me (localhost [127.0.0.1]) by tomli.me (OpenSMTPD) with ESMTP id d58028c4; Sat, 16 Mar 2019 22:25:29 +0000 (UTC) X-HELO: localhost.lan Authentication-Results: tomli.me; auth=pass (login) smtp.auth=tomli Received: from Unknown (HELO localhost.lan) (2402:f000:1:1501:200:5efe:6fc7:8b2c) by tomli.me (qpsmtpd/0.95) with ESMTPSA (DHE-RSA-CHACHA20-POLY1305 encrypted); Sat, 16 Mar 2019 22:25:29 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; d=tomli.me; h=from:to:cc:subject:date:message-id:in-reply-to:references:mime-version:content-transfer-encoding; s=1490979754; bh=4NWBd3Ia346Cajmo+kDBGhGRvuiTuYQgNlRiz0JnB94=; b=Nj6NsDspA6ghIdTmqBt6/yGdH4GCF7YlrSaMClTWthphTL5CLeKE5jWTtJ3k3bFXfSy5n0Ej15NbnSV/9gFpYCFw28k17ECV4ZJ0R7P5RgjyaXTPxVPVHb2g+5xPH5vOkDRhssFVgyh0XtyjeeFW1ep6zLQk83B4i2e/LyzYB5mHLffvyVZmqjbgtymnR3Qm/FmRbjlYssYp2Ryt1jPWirIYJgJ7hq/I5mGSh8y97BRz02NWkybBhtKZrXjoMlrblhvRr+CGbYZGhwwmCdSFCR1blJwnj/qxFLR2yuyNv58AYHGzKGtTMgFsWw8IL+mU/b/qSfKQl+lzXXcyxMBF/A== From: Yifeng Li To: Sudip Mukherjee , Teddy Wang Cc: Bartlomiej Zolnierkiewicz , linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Yifeng Li , stable@vger.kernel.org Subject: [PATCH 3/8] fbdev: sm712fb: fix VRAM detection, don't set SR70/71/74/75. Date: Sun, 17 Mar 2019 06:24:59 +0800 Message-Id: <20190316222504.27170-4-tomli@tomli.me> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190316222504.27170-1-tomli@tomli.me> References: <20190316222504.27170-1-tomli@tomli.me> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On a Thinkpad s30 (Pentium III / i440MX, Lynx3DM), the amount of Video RAM is not detected correctly by the xf86-video-siliconmotion driver. This is because sm712fb overwrites the GPR71 Scratch Pad Register, which is set by BIOS on x86 and used to indicate amount of VRAM. Other Scratch Pad Registers, including GPR70/74/75, don't have the same side-effect, but overwriting to them is still questionable, as they are not related to modesetting. Stop writing to SR70/71/74/75 (a.k.a GPR70/71/74/75). Signed-off-by: Yifeng Li Cc: stable@vger.kernel.org # v4.4+ --- drivers/video/fbdev/sm712fb.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/video/fbdev/sm712fb.c b/drivers/video/fbdev/sm712fb.c index a19655babf67..1a3d232c2916 100644 --- a/drivers/video/fbdev/sm712fb.c +++ b/drivers/video/fbdev/sm712fb.c @@ -1146,7 +1146,9 @@ static void sm7xx_set_timing(struct smtcfb_info *sfb) /* init SEQ register SR30 - SR75 */ for (i = 0; i < SIZE_SR30_SR75; i++) if ((i + 0x30) != 0x30 && (i + 0x30) != 0x62 && - (i + 0x30) != 0x6a && (i + 0x30) != 0x6b) + (i + 0x30) != 0x6a && (i + 0x30) != 0x6b && + (i + 0x30) != 0x70 && (i + 0x30) != 0x71 && + (i + 0x30) != 0x74 && (i + 0x30) != 0x75) smtc_seqw(i + 0x30, vgamode[j].init_sr30_sr75[i]); -- 2.20.1