From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=0.2 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.4 Received: (qmail 9619 invoked from network); 2 Mar 2022 12:43:14 -0000 Received: from 4ess.inri.net (216.126.196.42) by inbox.vuxu.org with ESMTPUTF8; 2 Mar 2022 12:43:14 -0000 Received: from mail-pj1-f48.google.com ([209.85.216.48]) by 4ess; Wed Mar 2 05:27:35 -0500 2022 Received: by mail-pj1-f48.google.com with SMTP id k5-20020a17090a3cc500b001befa0d3102so806729pjd.1 for <9front@9front.org>; Wed, 02 Mar 2022 02:27:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mforney.org; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=YnVDlHcQzYfhD0ISm0ypML/EzKFzDBrjRRZ9WDg/1PY=; b=vPut6dfm6LbklS/q9XyVvuKQVnXOZF+xKFGnQ+qybZG7jI6jvmgk/rIbYViTEpYvxp vY19BJwrJwQsnki3bTMgZNxiycYb+flP2+m8mI4MBX5RQnpSNC24R+awYyeKR5SUmXzC elzQrdOwm1wMhLN3eOZrAAxwa++9YOI5fnk/ET3wQmX//Wf/6FvEsf/JYhS3nukVQ8Qi bZyhHhBpSTPlO0Vck5egL5+1g93y32E2CTKHH0Thx6u+6JU4MLbwpRygBee4LIn1RvD/ XfhBgA97eIWSGl194FE70jnluNhRCh6nrfpGOnrRZL1VMBAcprmNXZ16i10Pvo4IHjXq VY1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=YnVDlHcQzYfhD0ISm0ypML/EzKFzDBrjRRZ9WDg/1PY=; b=SLSd35WZ6agfAbOyBsr9yZBxOTXEvNHUFsHOTnVw4hajrpUTZVHNLVs6pmxsAYfz9R h1pTT3fg4C825gN/qV7LRXvcYjxGBS++ALGH2QTbWRz8iKCP91J1cxltqfTIqkdYC2Md U+H98rrISQx81jXoczqJD2QYkXfcRTtLtEFSewtbXl0AaSfhII1Sc5P7aqhaHQefE/yj oNPr6s2/zrVz0kH1k5WDI+37MoVuGcTzoBdmWDGN6JhAjpmFpouCckklCxRUCl05GihZ geZHTjUZ7ITWTgVTCqv9/U3St4B76Wn/4KxMbzDG4ZzAdWqmcKA+pT4PflMLhzTunqhs Y6gA== X-Gm-Message-State: AOAM530DhS2LbcmnqshkowftPQQVpaxNlP/Xe8tHIlDstIRmLu32nlDr dYpsuE681pqO+scDje/D2aVzMy+FQoGFhNHbCIc= X-Google-Smtp-Source: ABdhPJwlHWACoXjG0oGDyTw/H7o0IxiZgFrGL0ry6MMBmfwP3pgog8kGMs7AjLMuJva1mCdCmdmCKg== X-Received: by 2002:a17:903:20cb:b0:150:c60:28e2 with SMTP id i11-20020a17090320cb00b001500c6028e2mr29655916plb.80.1646216842219; Wed, 02 Mar 2022 02:27:22 -0800 (PST) Return-Path: Received: from localhost ([98.45.152.168]) by smtp.gmail.com with ESMTPSA id v14-20020a056a00148e00b004e1cee6f6b4sm21052125pfu.47.2022.03.02.02.27.21 for <9front@9front.org> (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Wed, 02 Mar 2022 02:27:21 -0800 (PST) From: Michael Forney To: 9front@9front.org Date: Wed, 2 Mar 2022 02:26:36 -0800 Message-Id: <20220302102638.14043-2-mforney@mforney.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220302102638.14043-1-mforney@mforney.org> References: <20220302102638.14043-1-mforney@mforney.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit List-ID: <9front.9front.org> List-Help: X-Glyph: ➈ X-Bullshit: hosting hosting optimizer Subject: [9front] [PATCH 1/3] igfx: maintain single/double-channel LVDS mode from BIOS Reply-To: 9front@9front.org Precedence: bulk --- Not quite sure why single-channel mode doesn't work on my laptop; I just get a backlit black screen. The linux driver seems to use whatever the BIOS set, so it seems like we should do the same. The linux driver also has a parameter i915.lvds_channel_mode to force single/double channel. I confirmed that when I set i915.lvds_channel_mode=1, I get a black screen in linux as well. So I think it may be a hardware limitation rather than something igfx is doing wrong. sys/src/cmd/aux/vga/igfx.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/sys/src/cmd/aux/vga/igfx.c b/sys/src/cmd/aux/vga/igfx.c index a2537329b..db283587b 100644 --- a/sys/src/cmd/aux/vga/igfx.c +++ b/sys/src/cmd/aux/vga/igfx.c @@ -850,7 +850,12 @@ initdpll(Igfx *igfx, int x, int freq, int port) dpll->ctrl.v &= ~(3<<24); if(port == PortLCD){ p2 = 14; - if(freq > 112*MHz){ + /* + * Use dual-channel LVDS if the display clock is + * outside the range of single-channel, or it was + * preconfigured by the BIOS. + */ + if(freq > 112*MHz || (igfx->lvds.v>>4 & 3) == 3){ p2 >>= 1; dpll->ctrl.v |= (1<<24); } -- 2.34.1