From patchwork Mon Apr 11 13:00:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Westerberg X-Patchwork-Id: 559951 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CCC74C433FE for ; Mon, 11 Apr 2022 13:01:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346334AbiDKNDQ (ORCPT ); Mon, 11 Apr 2022 09:03:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55514 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346318AbiDKNDM (ORCPT ); Mon, 11 Apr 2022 09:03:12 -0400 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82DAF27FE7 for ; Mon, 11 Apr 2022 06:00:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1649682058; x=1681218058; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=RinVWMSAMfLXUIEiMy6OWdKgga6uVSUGl9anc1CGrfY=; b=N291M0wHgL6U16t0/9KlAwAZBINBz1TyOqjDXHa9fMwtE9GvmV/1UWoY UjMPcarQPpYGJBt14SecX2EjR2qIf0X7kpptik+m7hc4KplRx7lzBx59/ zXFOCJFlD4il3Gd0heQT41vuDnp5hFR50Km50WW900A59zIa0hMzVCVor igF31dG/FQEtTsa9wjdSnkMzMWC+RBMvSJg7qEde0VLwwJAmi/58V+3S+ lo9R9ifyjGWGQiEoVIRy4ysVaj/TInCd+vDjSzdEZu+DvCEmKMUH7qzcq 8PM9IqGWNZyrUVavIjGgt+FnfBi7u9tJ5znn3TcLu5rluybrlDoU4coH9 g==; X-IronPort-AV: E=McAfee;i="6400,9594,10313"; a="242695528" X-IronPort-AV: E=Sophos;i="5.90,251,1643702400"; d="scan'208";a="242695528" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Apr 2022 06:00:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,251,1643702400"; d="scan'208";a="572116726" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga008.jf.intel.com with ESMTP; 11 Apr 2022 06:00:49 -0700 Received: by black.fi.intel.com (Postfix, from userid 1001) id 6D4B0449; Mon, 11 Apr 2022 16:00:49 +0300 (EEST) From: Mika Westerberg To: linux-usb@vger.kernel.org Cc: Yehezkel Bernat , Michael Jamet , Andreas Noever , Lukas Wunner , Brad Campbell Subject: [PATCH 4/4] thunderbolt: Use different lane for second DisplayPort tunnel Date: Mon, 11 Apr 2022 16:00:49 +0300 Message-Id: <20220411130049.53656-4-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220411130049.53656-1-mika.westerberg@linux.intel.com> References: <20220411130049.53656-1-mika.westerberg@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Brad reported that on Apple hardware with Light Ridge or Falcon Ridge controller, plugging in a chain of Thunderbolt displays (Light Ridge based controllers) causes all kinds of tearing and flickering. The reason for this is that on Thunderbolt 1 hardware there is no lane bonding so we have two independent 10 Gb/s lanes, and currently Linux tunnels both displays through the lane 1. This makes the displays to share the 10 Gb/s bandwidth which may not be enough for higher resolutions. For this reason make the second tunnel go through the lane 0 instead. This seems to match what the macOS connection manager is also doing. Reported-by: Brad Campbell Signed-off-by: Mika Westerberg --- drivers/thunderbolt/tb.c | 19 +++++++++++++++++-- drivers/thunderbolt/test.c | 16 ++++++++-------- drivers/thunderbolt/tunnel.c | 11 ++++++----- drivers/thunderbolt/tunnel.h | 4 ++-- 4 files changed, 33 insertions(+), 17 deletions(-) diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c index 9beb47b31c75..44d04b651a8b 100644 --- a/drivers/thunderbolt/tb.c +++ b/drivers/thunderbolt/tb.c @@ -867,7 +867,7 @@ static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in) static void tb_tunnel_dp(struct tb *tb) { - int available_up, available_down, ret; + int available_up, available_down, ret, link_nr; struct tb_cm *tcm = tb_priv(tb); struct tb_port *port, *in, *out; struct tb_tunnel *tunnel; @@ -912,6 +912,20 @@ static void tb_tunnel_dp(struct tb *tb) return; } + /* + * This is only applicable to links that are not bonded (so + * when Thunderbolt 1 hardware is involved somewhere in the + * topology). For these try to share the DP bandwidth between + * the two lanes. + */ + link_nr = 1; + list_for_each_entry(tunnel, &tcm->tunnel_list, list) { + if (tb_tunnel_is_dp(tunnel)) { + link_nr = 0; + break; + } + } + /* * DP stream needs the domain to be active so runtime resume * both ends of the tunnel. @@ -943,7 +957,8 @@ static void tb_tunnel_dp(struct tb *tb) tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n", available_up, available_down); - tunnel = tb_tunnel_alloc_dp(tb, in, out, available_up, available_down); + tunnel = tb_tunnel_alloc_dp(tb, in, out, link_nr, available_up, + available_down); if (!tunnel) { tb_port_dbg(out, "could not allocate DP tunnel\n"); goto err_reclaim; diff --git a/drivers/thunderbolt/test.c b/drivers/thunderbolt/test.c index 1f69bab236ee..66b6e665e96f 100644 --- a/drivers/thunderbolt/test.c +++ b/drivers/thunderbolt/test.c @@ -1348,7 +1348,7 @@ static void tb_test_tunnel_dp(struct kunit *test) in = &host->ports[5]; out = &dev->ports[13]; - tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0); + tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0); KUNIT_ASSERT_TRUE(test, tunnel != NULL); KUNIT_EXPECT_EQ(test, tunnel->type, TB_TUNNEL_DP); KUNIT_EXPECT_PTR_EQ(test, tunnel->src_port, in); @@ -1394,7 +1394,7 @@ static void tb_test_tunnel_dp_chain(struct kunit *test) in = &host->ports[5]; out = &dev4->ports[14]; - tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0); + tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0); KUNIT_ASSERT_TRUE(test, tunnel != NULL); KUNIT_EXPECT_EQ(test, tunnel->type, TB_TUNNEL_DP); KUNIT_EXPECT_PTR_EQ(test, tunnel->src_port, in); @@ -1444,7 +1444,7 @@ static void tb_test_tunnel_dp_tree(struct kunit *test) in = &dev2->ports[13]; out = &dev5->ports[13]; - tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0); + tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0); KUNIT_ASSERT_TRUE(test, tunnel != NULL); KUNIT_EXPECT_EQ(test, tunnel->type, TB_TUNNEL_DP); KUNIT_EXPECT_PTR_EQ(test, tunnel->src_port, in); @@ -1509,7 +1509,7 @@ static void tb_test_tunnel_dp_max_length(struct kunit *test) in = &dev6->ports[13]; out = &dev12->ports[13]; - tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0); + tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0); KUNIT_ASSERT_TRUE(test, tunnel != NULL); KUNIT_EXPECT_EQ(test, tunnel->type, TB_TUNNEL_DP); KUNIT_EXPECT_PTR_EQ(test, tunnel->src_port, in); @@ -1627,7 +1627,7 @@ static void tb_test_tunnel_port_on_path(struct kunit *test) in = &dev2->ports[13]; out = &dev5->ports[13]; - dp_tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0); + dp_tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0); KUNIT_ASSERT_TRUE(test, dp_tunnel != NULL); KUNIT_EXPECT_TRUE(test, tb_tunnel_port_on_path(dp_tunnel, in)); @@ -2009,7 +2009,7 @@ static void tb_test_credit_alloc_dp(struct kunit *test) in = &host->ports[5]; out = &dev->ports[14]; - tunnel = tb_tunnel_alloc_dp(NULL, in, out, 0, 0); + tunnel = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0); KUNIT_ASSERT_TRUE(test, tunnel != NULL); KUNIT_ASSERT_EQ(test, tunnel->npaths, (size_t)3); @@ -2245,7 +2245,7 @@ static struct tb_tunnel *TB_TEST_DP_TUNNEL1(struct kunit *test, in = &host->ports[5]; out = &dev->ports[13]; - dp_tunnel1 = tb_tunnel_alloc_dp(NULL, in, out, 0, 0); + dp_tunnel1 = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0); KUNIT_ASSERT_TRUE(test, dp_tunnel1 != NULL); KUNIT_ASSERT_EQ(test, dp_tunnel1->npaths, (size_t)3); @@ -2282,7 +2282,7 @@ static struct tb_tunnel *TB_TEST_DP_TUNNEL2(struct kunit *test, in = &host->ports[6]; out = &dev->ports[14]; - dp_tunnel2 = tb_tunnel_alloc_dp(NULL, in, out, 0, 0); + dp_tunnel2 = tb_tunnel_alloc_dp(NULL, in, out, 1, 0, 0); KUNIT_ASSERT_TRUE(test, dp_tunnel2 != NULL); KUNIT_ASSERT_EQ(test, dp_tunnel2->npaths, (size_t)3); diff --git a/drivers/thunderbolt/tunnel.c b/drivers/thunderbolt/tunnel.c index 118742ec93ed..8ccd70920b6a 100644 --- a/drivers/thunderbolt/tunnel.c +++ b/drivers/thunderbolt/tunnel.c @@ -858,6 +858,7 @@ struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in, * @tb: Pointer to the domain structure * @in: DP in adapter port * @out: DP out adapter port + * @link_nr: Preferred lane adapter when the link is not bonded * @max_up: Maximum available upstream bandwidth for the DP tunnel (%0 * if not limited) * @max_down: Maximum available downstream bandwidth for the DP tunnel @@ -869,8 +870,8 @@ struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in, * Return: Returns a tb_tunnel on success or NULL on failure. */ struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in, - struct tb_port *out, int max_up, - int max_down) + struct tb_port *out, int link_nr, + int max_up, int max_down) { struct tb_tunnel *tunnel; struct tb_path **paths; @@ -894,21 +895,21 @@ struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in, paths = tunnel->paths; path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID, - 1, "Video"); + link_nr, "Video"); if (!path) goto err_free; tb_dp_init_video_path(path); paths[TB_DP_VIDEO_PATH_OUT] = path; path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out, - TB_DP_AUX_TX_HOPID, 1, "AUX TX"); + TB_DP_AUX_TX_HOPID, link_nr, "AUX TX"); if (!path) goto err_free; tb_dp_init_aux_path(path); paths[TB_DP_AUX_PATH_OUT] = path; path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in, - TB_DP_AUX_RX_HOPID, 1, "AUX RX"); + TB_DP_AUX_RX_HOPID, link_nr, "AUX RX"); if (!path) goto err_free; tb_dp_init_aux_path(path); diff --git a/drivers/thunderbolt/tunnel.h b/drivers/thunderbolt/tunnel.h index 03e56076b5bc..bb4d1f1d6d0b 100644 --- a/drivers/thunderbolt/tunnel.h +++ b/drivers/thunderbolt/tunnel.h @@ -71,8 +71,8 @@ struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up, struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in, bool alloc_hopid); struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in, - struct tb_port *out, int max_up, - int max_down); + struct tb_port *out, int link_nr, + int max_up, int max_down); struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi, struct tb_port *dst, int transmit_path, int transmit_ring, int receive_path,