From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A044226ACC for ; Tue, 21 Apr 2026 04:45:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776746748; cv=none; b=fZ4599DjJNexSDNjMMRdaNGRy4F21oSQIgRRqWZ3fED7cnMmqBHgyQ8hTB73ojAmudEFxSmaVtLQlC3gGazDY0Wd0hm1O28U9z+N3wbkUidOrYQCF4f4IdBB0yhRw31TTAtKfef66W7W0wnXbqNRT5Q2TAEaNOu1gPMbN3DO6NI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776746748; c=relaxed/simple; bh=IHKDrg7cPuZh6SeYBWJF66K4+eswB/V3HUJn5K628HI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=XDDOoN3RtyFFLC4gmbQIuziCEdG9hHxxKHu8F86OPETerMDKd4PwJCHT5lVx7N1T7zBEy+SbvseGMXsxrovfttT2rmKqXH5+lAGG3mI9UKoeEXIcrJi5qaaIfo+bO9Zy5ceMCTUGWt021eTQuKJ+1lAUkT1fiC9hMKMivpcMrZ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=jC89sHcy; arc=none smtp.client-ip=192.198.163.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="jC89sHcy" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1776746747; x=1808282747; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=IHKDrg7cPuZh6SeYBWJF66K4+eswB/V3HUJn5K628HI=; b=jC89sHcysYigkYYsGrgEms47K27hbgUUrgoMIe2KBvM76bIsMETo5cZZ l5Q/7rlznf5jofbDTtcxURYI8fY2OlXggXlPwzYBO7ug4vDM63d0Y/wB1 TmKWHvwJtihklMLAE7x8sanFBL+Mjag26Dua1W/1wWVnHp3E7q78R8r+G Fh/ZZgbg5uGTuXyGN8aXBa6LBpAa8ohkTXNWPlKqdHpkwca6t6HHoL6gw Zal3tYBfNuN4xmbATsUzr0mAZIlTgWcL/ykehggPRvlTGVete+LoTYhA5 oZELZuWbzlhqXrOruRmfHifnjQEfGnssrkoF84hc/Ki+AmbBxv6pK4nKV g==; X-CSE-ConnectionGUID: jRqIVUkISIS0zrnislgAsw== X-CSE-MsgGUID: 1QxREO8QRhyaeP1tO5VmQw== X-IronPort-AV: E=McAfee;i="6800,10657,11762"; a="80261109" X-IronPort-AV: E=Sophos;i="6.23,191,1770624000"; d="scan'208";a="80261109" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Apr 2026 21:45:46 -0700 X-CSE-ConnectionGUID: 3g8bq7RqTVKDJg9YslSzuA== X-CSE-MsgGUID: bK4x4j0MSs2VtqWS1JJTFA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,191,1770624000"; d="scan'208";a="228761144" Received: from black.igk.intel.com ([10.91.253.5]) by fmviesa007.fm.intel.com with ESMTP; 20 Apr 2026 21:45:44 -0700 Received: by black.igk.intel.com (Postfix, from userid 1001) id EAC2295; Tue, 21 Apr 2026 06:45:42 +0200 (CEST) Date: Tue, 21 Apr 2026 06:45:42 +0200 From: Mika Westerberg To: Rodrigo Vivi Cc: Francesco Orro , intel-gfx@lists.freedesktop.org, Imre Deak , Ville =?utf-8?B?U3lyasOkbMOk?= , Uma Shankar , "dri-devel@lists.freedesktop.org" , "linux-usb@vger.kernel.org" , Jani Nikula Subject: Re: DP routing from iGPU to discrete Barlow Ridge TB5 on HP ZBook Fury G1i Message-ID: <20260421044542.GA557136@black.igk.intel.com> References: Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Mon, Apr 20, 2026 at 04:47:25PM -0400, Rodrigo Vivi wrote: > On Mon, Apr 20, 2026 at 04:04:02PM +0000, Francesco Orro wrote: > > Hi, > > > > Setup: > > HP ZBook Fury G1i 16 inch, BIOS X96 01.03.04 > > Intel Arrow Lake-HX + Nvidia RTX PRO 1000 Blackwell (hybrid graphics) > > Kernel 6.19.13 > > > > The laptop exposes Thunderbolt 5 on both the integrated MTL iTBT (right > > USB-C, domain0, 00:0d.2) and a discrete Intel Barlow Ridge (left USB-C, > > domain1, 00:06.1 -> 05:00.0). > > > > - Right port: i915 drives a DP tunnel over the iTBT host without issues. > > - Left port: no i915 connector ever sees the external monitor. The TB > > driver allocates a DP tunnel on demand but DPRX reads time out, no DP > > source is feeding the Barlow DP_IN adapter. > > - With nvidia-drm.modeset=1, a DP-MST connector on the Nvidia DRM device > > sees the monitor via the left port (EDID readable, modes negotiated). > > The path Nvidia -> Barlow DP_IN is functional. > > > > Current hypothesis: on this board the discrete Barlow Ridge DP_IN is > > either hardwired to a Nvidia output or behind a firmware-programmed mux > > that BIOS latches to Nvidia at POST and is not exposed to the OS. i915 > > would therefore have no path to drive the left ports, by design. > > yes, that is usually the case. > > > > > Tests done that did not surface an OS-visible lever: > > - i2cdetect across all SMBus/i801 busses: no DP mux/retimer at plausible > > addresses (0x60-0x7F). > > - DSDT/SSDT dump (iasl -d): no Device/Method referring to DP routing, > > DPMUX, retimer programming, or dock display source selection. > > - HP WMI + /sys/devices/virtual/firmware-attributes/hp-bioscfg attribute > > enumeration: nothing switching dock display source. "Graphics" > > attribute only offers Hybrid/Discrete. > > - PCI config dump of Barlow Ridge: standard USB4 NHI, no vendor-specific > > capability hinting at source selection. > > - acpi.no_usb4_osc kernel param (locally patched) to opt out of OSC USB4 > > native support: no change in i915 visibility of the dock. > > > > Is there any known way to route an Intel DDI output to a PCIe-attached > > Barlow Ridge DP_IN adapter, or is this strictly a design where the dGPU > > is the only valid DP source for the discrete TB controller on this class > > of HP workstations? > > I believe this is physically connected or static mux without any way to > re-route this. But I might be wrong. > This is my understanding too based on the systems I've seen.