From nobody Sun Nov 24 09:28:20 2024 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E78A51D86C9; Wed, 6 Nov 2024 02:14:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730859287; cv=none; b=mBoKvLI9X8XNt/qDKL37vmbWGyUv5XDHzPnF5jXQ8gpdW5icqX3NU8Me67pqsIRCH5DX6b0Ik2N/UExwd0nvW/TfODzEzznlNa7MZ/+EQB7bhYHPrBPFWtdAdwV4UpyrhEhVt+AqJ1envaBGz3oyCsx68ecMQDzodGytiNaPzaw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730859287; c=relaxed/simple; bh=JyPJGtsm3K6JU32Nz/iopXhqEVlPNysU3RBw17FVilc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=iFRAffa6O2t3gR1LyugU4QD7HM3NKdkI9V01L8ZAUSvnf8xlRtspV2H77+WRRIa/hUeohXXw6I7RF7Uv1H5kKzQjyXmtj+9A0bhcym81yaV0vwC70rV/UYhbae4+LdaFJcGLH8VOifrRknwhb/mIGIMtl6pK9KW6NraXT9z8ywE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nO9n2cDy; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nO9n2cDy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F3F88C4CECF; Wed, 6 Nov 2024 02:14:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730859286; bh=JyPJGtsm3K6JU32Nz/iopXhqEVlPNysU3RBw17FVilc=; h=From:To:Cc:Subject:Date:From; b=nO9n2cDy4CLNx+EX4Zmsxf8FZyiuKHxz5VoZi4tQXlEGmmKl5yOpEGI60uUeHBkT1 Yukp8Tb6dgy1ltoHvY5KnzTUSmTGiuh7evRLKPzpnDdAua3c7VINfot1WzyUi8VQVV 6Q9IOzlWYKvud1rnhcwBOkWpO0MsW9XM40hqjMMIhkpORJkvTdbZF9/IhfhbW2R0l7 xvMuXVFKTDjPnYcdmYLU9yzbySzboE6g3rZlsg+y4Zb1eDJ5qD08uRuvicI4F/OyWu WacVGFZF/j2PuyzmGnNK7U1WjzRXV9VcNCsP9VyHa/TGSmsjU/7UWvMW3eqnUohffd 1Pmag3ke3A5+A== From: Sasha Levin To: stable@vger.kernel.org, gil.fine@linux.intel.com Cc: Mika Westerberg , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: FAILED: Patch "thunderbolt: Honor TMU requirements in the domain when setting TMU mode" failed to apply to v4.19-stable tree Date: Tue, 5 Nov 2024 21:14:43 -0500 Message-ID: <20241106021444.184480-1-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Hint: ignore X-stable: review Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The patch below does not apply to the v4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . Thanks, Sasha ------------------ original commit in Linus's tree ------------------ From 3cea8af2d1a9ae5869b47c3dabe3b20f331f3bbd Mon Sep 17 00:00:00 2001 From: Gil Fine Date: Thu, 10 Oct 2024 17:29:42 +0300 Subject: [PATCH] thunderbolt: Honor TMU requirements in the domain when setting TMU mode Currently, when configuring TMU (Time Management Unit) mode of a given router, we take into account only its own TMU requirements ignoring other routers in the domain. This is problematic if the router we are configuring has lower TMU requirements than what is already configured in the domain. In the scenario below, we have a host router with two USB4 ports: A and B. Port A connected to device router #1 (which supports CL states) and existing DisplayPort tunnel, thus, the TMU mode is HiFi uni-directional. 1. Initial topology [Host] A/ / [Device #1] / Monitor 2. Plug in device #2 (that supports CL states) to downstream port B of the host router [Host] A/ B\ / \ [Device #1] [Device #2] / Monitor The TMU mode on port B and port A will be configured to LowRes which is not what we want and will cause monitor to start flickering. To address this we first scan the domain and search for any router configured to HiFi uni-directional mode, and if found, configure TMU mode of the given router to HiFi uni-directional as well. Cc: stable@vger.kernel.org Signed-off-by: Gil Fine Signed-off-by: Mika Westerberg --- drivers/thunderbolt/tb.c | 48 +++++++++++++++++++++++++++++++++++----- 1 file changed, 42 insertions(+), 6 deletions(-) diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c index 10e719dd837ce..4f777788e9179 100644 --- a/drivers/thunderbolt/tb.c +++ b/drivers/thunderbolt/tb.c @@ -288,6 +288,24 @@ static void tb_increase_tmu_accuracy(struct tb_tunnel = *tunnel) device_for_each_child(&sw->dev, NULL, tb_increase_switch_tmu_accuracy); } =20 +static int tb_switch_tmu_hifi_uni_required(struct device *dev, void *not_u= sed) +{ + struct tb_switch *sw =3D tb_to_switch(dev); + + if (sw && tb_switch_tmu_is_enabled(sw) && + tb_switch_tmu_is_configured(sw, TB_SWITCH_TMU_MODE_HIFI_UNI)) + return 1; + + return device_for_each_child(dev, NULL, + tb_switch_tmu_hifi_uni_required); +} + +static bool tb_tmu_hifi_uni_required(struct tb *tb) +{ + return device_for_each_child(&tb->dev, NULL, + tb_switch_tmu_hifi_uni_required) =3D=3D 1; +} + static int tb_enable_tmu(struct tb_switch *sw) { int ret; @@ -302,12 +320,30 @@ static int tb_enable_tmu(struct tb_switch *sw) ret =3D tb_switch_tmu_configure(sw, TB_SWITCH_TMU_MODE_MEDRES_ENHANCED_UNI); if (ret =3D=3D -EOPNOTSUPP) { - if (tb_switch_clx_is_enabled(sw, TB_CL1)) - ret =3D tb_switch_tmu_configure(sw, - TB_SWITCH_TMU_MODE_LOWRES); - else - ret =3D tb_switch_tmu_configure(sw, - TB_SWITCH_TMU_MODE_HIFI_BI); + if (tb_switch_clx_is_enabled(sw, TB_CL1)) { + /* + * Figure out uni-directional HiFi TMU requirements + * currently in the domain. If there are no + * uni-directional HiFi requirements we can put the TMU + * into LowRes mode. + * + * Deliberately skip bi-directional HiFi links + * as these work independently of other links + * (and they do not allow any CL states anyway). + */ + if (tb_tmu_hifi_uni_required(sw->tb)) + ret =3D tb_switch_tmu_configure(sw, + TB_SWITCH_TMU_MODE_HIFI_UNI); + else + ret =3D tb_switch_tmu_configure(sw, + TB_SWITCH_TMU_MODE_LOWRES); + } else { + ret =3D tb_switch_tmu_configure(sw, TB_SWITCH_TMU_MODE_HIFI_BI); + } + + /* If not supported, fallback to bi-directional HiFi */ + if (ret =3D=3D -EOPNOTSUPP) + ret =3D tb_switch_tmu_configure(sw, TB_SWITCH_TMU_MODE_HIFI_BI); } if (ret) return ret; --=20 2.43.0