From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.tq-group.com (mx1.tq-group.com [93.104.207.81]) (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 4EEBF1FBB for ; Wed, 26 Jun 2024 07:36:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=93.104.207.81 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719387374; cv=none; b=AekdeQ3Pr5G8CU+dv1OnOsVytxb6O4fHEcTwFqr4O0jsPgJfbNnyXksJo77KiqRaHMyPsRL4Q+Y1MPblasbZRx42WKmOgVz3m/Ig//HtK397muXqw19wUhK7UzO8Rk6ysrVt3AiFXfar2OCr4EN/2MRikU9ZwRMkJO7dDcAzqY0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719387374; c=relaxed/simple; bh=epLKZ9UwJ7uXkbMnttY9VERqSnhD5nhWVaOg2+aO01k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=a51AZNFXs+N5NMEt1xcoQWA0FCJBdbkCKIJltNCtlLroi79u/jHLciNCpAqetCAqDCsIEHep/RkhQMbgeMpu9/HUSL4JMqcnjnwJYKeeKZsJVzUBpSMvhq2oJaW+uDRdfyRmvBuld8SuqFkxQL8qiY5khrWHT4eimlCCMa8UVkg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ew.tq-group.com; spf=pass smtp.mailfrom=ew.tq-group.com; dkim=pass (2048-bit key) header.d=tq-group.com header.i=@tq-group.com header.b=aGYMLsTv; dkim=fail (0-bit key) header.d=ew.tq-group.com header.i=@ew.tq-group.com header.b=UEnA1V5c reason="key not found in DNS"; arc=none smtp.client-ip=93.104.207.81 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ew.tq-group.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ew.tq-group.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=tq-group.com header.i=@tq-group.com header.b="aGYMLsTv"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=ew.tq-group.com header.i=@ew.tq-group.com header.b="UEnA1V5c" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1719387371; x=1750923371; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=w8ZWPITAV4BVFXhLX83ZUdLQbrWkmuEHynQtO0CvwUE=; b=aGYMLsTvPgABCRIb5S8EIimXo+wi9F4wDm9qeRQxZIHtCu4bZoBSm1xl ChToYGXmVCMkYNc0jeeEdTDy36aBNa0Lfu+DRvIJfq2DuxeE6EN8DPq27 UH+22nWzxg7Cr9GiUTZV6gDoYSdSKN/SOOUqiM50mKInKqZ7AFchgYUpp HY6aUBRt9IHaq1SpoDVtLRsaMPwayVZjnAnmucW3P5gE5qB/dxA/n7Qzm gpzDEZxM4qcd5Essu9vNqvvlbYjzJmXBKWnl0+jd+xboXVAP04IZInIdf ZUeK6u0yp+P3fKA3WRrl8m2bjc86IGlZA/tmMuRM7MUHOVisDuLR3oX8g A==; X-CSE-ConnectionGUID: T3ef1K60TsmKdKCtk2/4pg== X-CSE-MsgGUID: wX6UFoD3TOqNEsW+E5RIgw== X-IronPort-AV: E=Sophos;i="6.08,266,1712613600"; d="scan'208";a="37591305" Received: from vmailcow01.tq-net.de ([10.150.86.48]) by mx1.tq-group.com with ESMTP; 26 Jun 2024 09:36:09 +0200 Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id CEF0516361F; Wed, 26 Jun 2024 09:36:00 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ew.tq-group.com; s=dkim; t=1719387364; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=w8ZWPITAV4BVFXhLX83ZUdLQbrWkmuEHynQtO0CvwUE=; b=UEnA1V5cm9unZEOZ67we5C2V0xRBushkfydC8VQcA+rfxT6FsxRJKYI8X2qCFu+1ZVj4hR E/SXZL4jYkmg2PYvHifwN8JONRArq065VsQqCI+9hPuGRlfMjO6QxF0/WRm5oclKBc8aSu ZUylOVNwCO0rv96JA925lPXou4ziOWUvKK2iY6sWUOdvDDlGX8Tlszsk6o67+7GskwQLE7 XswzRt+ZRCrqhYwrn41TaoQBOhcVKLAmVi+/33PKDKri5FQI5jaDklvvtgqu1/YunhpO6W 89+SiLcxSJf3FnKoozDcZly7kfa6KtqP6+gINJs8NHo2G4dP82FjDh4DrxnwLA== From: Alexander Stein To: dri-devel@lists.freedesktop.org Cc: Marek Vasut , Andrzej Hajda , Conor Dooley , Daniel Vetter , David Airlie , Jernej Skrabec , Jonas Karlman , Krzysztof Kozlowski , Laurent Pinchart , Lucas Stach , Maarten Lankhorst , Maxime Ripard , Neil Armstrong , Rob Herring , Robert Foss , Thomas Zimmermann , devicetree@vger.kernel.org, kernel@dh-electronics.com, Marek Vasut Subject: Re: [PATCH v3 2/2] drm/bridge: tc358767: Add configurable default preemphasis Date: Wed, 26 Jun 2024 09:36:03 +0200 Message-ID: <3293850.oiGErgHkdL@steina-w> Organization: TQ-Systems GmbH In-Reply-To: <20240625120552.145389-2-marex@denx.de> References: <20240625120552.145389-1-marex@denx.de> <20240625120552.145389-2-marex@denx.de> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" X-Last-TLS-Session-Version: TLSv1.3 Hi Marek, thanks for patch. Am Dienstag, 25. Juni 2024, 14:05:15 CEST schrieb Marek Vasut: > Make the default DP port preemphasis configurable via new DT property > "toshiba,pre-emphasis". This is useful in case the DP link properties > are known and starting link training from preemphasis setting of 0 dB > is not useful. The preemphasis can be set separately for both DP lanes > in range 0=3D0dB, 1=3D3.5dB, 2=3D6dB . >=20 > Signed-off-by: Marek Vasut > --- > Cc: Andrzej Hajda > Cc: Conor Dooley > Cc: Daniel Vetter > Cc: David Airlie > Cc: Jernej Skrabec > Cc: Jonas Karlman > Cc: Krzysztof Kozlowski > Cc: Laurent Pinchart > Cc: Lucas Stach > Cc: Maarten Lankhorst > Cc: Maxime Ripard > Cc: Neil Armstrong > Cc: Rob Herring > Cc: Robert Foss > Cc: Thomas Zimmermann > Cc: devicetree@vger.kernel.org > Cc: dri-devel@lists.freedesktop.org > Cc: kernel@dh-electronics.com > --- > V2: - Parse toshiba,pre-emphasis property out of an endpoint of port 2 (t= he DP port) > V3: - No change > --- > drivers/gpu/drm/bridge/tc358767.c | 45 ++++++++++++++++++++++++++----- > 1 file changed, 38 insertions(+), 7 deletions(-) >=20 > diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/t= c358767.c > index dde1b2734c98a..257fe15080099 100644 > --- a/drivers/gpu/drm/bridge/tc358767.c > +++ b/drivers/gpu/drm/bridge/tc358767.c > @@ -241,6 +241,10 @@ > =20 > /* Link Training */ > #define DP0_SRCCTRL 0x06a0 > +#define DP0_SRCCTRL_PRE1 GENMASK(29, 28) > +#define DP0_SRCCTRL_SWG1 GENMASK(25, 24) > +#define DP0_SRCCTRL_PRE0 GENMASK(21, 20) > +#define DP0_SRCCTRL_SWG0 GENMASK(17, 16) > #define DP0_SRCCTRL_SCRMBLDIS BIT(13) > #define DP0_SRCCTRL_EN810B BIT(12) > #define DP0_SRCCTRL_NOTP (0 << 8) > @@ -278,6 +282,8 @@ > #define AUDIFDATA6 0x0720 /* DP0 Audio Info Frame Bytes 27 to 24 */ > =20 > #define DP1_SRCCTRL 0x07a0 /* DP1 Control Register */ > +#define DP1_SRCCTRL_PRE GENMASK(21, 20) > +#define DP1_SRCCTRL_SWG GENMASK(17, 16) > =20 > /* PHY */ > #define DP_PHY_CTRL 0x0800 > @@ -369,6 +375,7 @@ struct tc_data { > =20 > u32 rev; > u8 assr; > + u8 pre_emphasis[2]; > =20 > struct gpio_desc *sd_gpio; > struct gpio_desc *reset_gpio; > @@ -1090,13 +1097,17 @@ static int tc_main_link_enable(struct tc_data *tc) > return ret; > } > =20 > - ret =3D regmap_write(tc->regmap, DP0_SRCCTRL, tc_srcctrl(tc)); > + ret =3D regmap_write(tc->regmap, DP0_SRCCTRL, > + tc_srcctrl(tc) | > + FIELD_PREP(DP0_SRCCTRL_PRE0, tc->pre_emphasis[0]) | > + FIELD_PREP(DP0_SRCCTRL_PRE1, tc->pre_emphasis[1])); > if (ret) > return ret; > /* SSCG and BW27 on DP1 must be set to the same as on DP0 */ > ret =3D regmap_write(tc->regmap, DP1_SRCCTRL, > (tc->link.spread ? DP0_SRCCTRL_SSCG : 0) | > - ((tc->link.rate !=3D 162000) ? DP0_SRCCTRL_BW27 : 0)); > + ((tc->link.rate !=3D 162000) ? DP0_SRCCTRL_BW27 : 0) | > + FIELD_PREP(DP1_SRCCTRL_PRE, tc->pre_emphasis[1])); > if (ret) > return ret; > =20 > @@ -1188,8 +1199,10 @@ static int tc_main_link_enable(struct tc_data *tc) > goto err_dpcd_write; > =20 > /* Reset voltage-swing & pre-emphasis */ > - tmp[0] =3D tmp[1] =3D DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | > - DP_TRAIN_PRE_EMPH_LEVEL_0; > + tmp[0] =3D DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | > + FIELD_PREP(DP_TRAIN_PRE_EMPHASIS_MASK, tc->pre_emphasis[0]); > + tmp[1] =3D DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | > + FIELD_PREP(DP_TRAIN_PRE_EMPHASIS_MASK, tc->pre_emphasis[1]); > ret =3D drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_SET, tmp, 2); > if (ret < 0) > goto err_dpcd_write; > @@ -1213,7 +1226,9 @@ static int tc_main_link_enable(struct tc_data *tc) > ret =3D regmap_write(tc->regmap, DP0_SRCCTRL, > tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS | > DP0_SRCCTRL_AUTOCORRECT | > - DP0_SRCCTRL_TP1); > + DP0_SRCCTRL_TP1 | > + FIELD_PREP(DP0_SRCCTRL_PRE0, tc->pre_emphasis[0]) | > + FIELD_PREP(DP0_SRCCTRL_PRE1, tc->pre_emphasis[1])); > if (ret) > return ret; > =20 > @@ -1248,7 +1263,9 @@ static int tc_main_link_enable(struct tc_data *tc) > ret =3D regmap_write(tc->regmap, DP0_SRCCTRL, > tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS | > DP0_SRCCTRL_AUTOCORRECT | > - DP0_SRCCTRL_TP2); > + DP0_SRCCTRL_TP2 | > + FIELD_PREP(DP0_SRCCTRL_PRE0, tc->pre_emphasis[0]) | > + FIELD_PREP(DP0_SRCCTRL_PRE1, tc->pre_emphasis[1])); > if (ret) > return ret; > =20 > @@ -1274,7 +1291,9 @@ static int tc_main_link_enable(struct tc_data *tc) > =20 > /* Clear Training Pattern, set AutoCorrect Mode =3D 1 */ > ret =3D regmap_write(tc->regmap, DP0_SRCCTRL, tc_srcctrl(tc) | > - DP0_SRCCTRL_AUTOCORRECT); > + DP0_SRCCTRL_AUTOCORRECT | > + FIELD_PREP(DP0_SRCCTRL_PRE0, tc->pre_emphasis[0]) | > + FIELD_PREP(DP0_SRCCTRL_PRE1, tc->pre_emphasis[1])); > if (ret) > return ret; > =20 > @@ -2435,6 +2454,18 @@ static int tc_probe_bridge_endpoint(struct tc_data= *tc) > return -EINVAL; > } > mode |=3D BIT(endpoint.port); > + if (endpoint.port !=3D 2) > + continue; > + Mh, I know currently there are not other port-specific properties. But maybe it's easier to read if 'if (endpoint.port =3D=3D 2) {' is used. But either way, this looks good. Acked-by: Alexander Stein > + of_property_read_u8_array(node, "toshiba,pre-emphasis", > + tc->pre_emphasis, > + ARRAY_SIZE(tc->pre_emphasis)); > + > + if (tc->pre_emphasis[0] < 0 || tc->pre_emphasis[0] > 2 || > + tc->pre_emphasis[1] < 0 || tc->pre_emphasis[1] > 2) { > + dev_err(dev, "Incorrect Pre-Emphasis setting, use either 0=3D0dB 1=3D= 3.5dB 2=3D6dB\n"); > + return -EINVAL; > + } > } > =20 > if (mode =3D=3D mode_dpi_to_edp || mode =3D=3D mode_dpi_to_dp) { >=20 =2D-=20 TQ-Systems GmbH | M=FChlstra=DFe 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht M=FCnchen, HRB 105018 Gesch=E4ftsf=FChrer: Detlef Schneider, R=FCdiger Stahl, Stefan Schneider http://www.tq-group.com/