From mboxrd@z Thu Jan 1 00:00:00 1970 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 B49C1127E37; Tue, 22 Oct 2024 07:53:47 +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=1729583627; cv=none; b=cEUDDPfcw+Dmc6CKAd+iO/JfRpdz3OzHtXRTdpaoSXUkS1lLYC02YxRAW0TV3qo+Wl9CoUKI7RFJ8mK8Q3thrPOH+h78KRB0zk7BSysbjTRI8BoCECtnEVdjCQ27W0DwP912KnGDePyD2rqUDrPJUhYy0fhxP5cdWcCaW/N9TTo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729583627; c=relaxed/simple; bh=94yBtoN+NpXDkZbfuTm6IbHirn/x4DZTEvDfAeXAcpA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=O+CvHS6dSa1oR+AwwSm83XwCy+dpOofL4ui5Ig9A+hyXEnz35X8PQn/cXZn9gTS2LnopUKbZdejEbxmfu/5Fy0+8+3zk57vxtKafS5L3uTNn1lXmfXlV/P7IkRsaJlepJXhhygR+TmkZMSiyPVZPSnaEiwjQA6ObUuOTJ9pC/JE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WP+vrCJG; 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="WP+vrCJG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 157F3C4CEC3; Tue, 22 Oct 2024 07:53:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729583627; bh=94yBtoN+NpXDkZbfuTm6IbHirn/x4DZTEvDfAeXAcpA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WP+vrCJGa7gZyLVrVwi+VFRTM0ScCecdKxk+Li7zOUiaDW2pfTG6XrcpVzRGv9STR T7OeATEZTlF+IPmvX0czoTTOOtsAP2de3OUrShTxlShJMVjoZ/9QRRQTLHnFIazkDM oI+HVzjH2p4APM0aW14CGQfNl9lvZGyKjDbEKgip52Bss+DcL0a1nOliVeJ+3p5aZ9 Wkdmh1eo8Wr+dfhbRH+zTuDP0aTU0AW2nJ5mDLB+bo2geepiQNAus+kMdvvTPfizSO pF9vugoJRndcp9osV0GvvkoAEOoeCWBPhf6CKZZg3cRUoEJ+jlKKKDFysKiyQb9vaG fMUjSgsr37F2g== Date: Tue, 22 Oct 2024 09:53:44 +0200 From: Maxime Ripard To: Liu Ying Cc: dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, airlied@gmail.com, simona@ffwll.ch, maarten.lankhorst@linux.intel.com, tzimmermann@suse.de, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, quic_jesszhan@quicinc.com, mchehab@kernel.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, catalin.marinas@arm.com, will@kernel.org, sakari.ailus@linux.intel.com, hverkuil@xs4all.nl, tomi.valkeinen@ideasonboard.com, quic_bjorande@quicinc.com, geert+renesas@glider.be, dmitry.baryshkov@linaro.org, arnd@arndb.de, nfraprado@collabora.com, thierry.reding@gmail.com, prabhakar.mahadev-lad.rj@bp.renesas.com, sam@ravnborg.org, marex@denx.de, biju.das.jz@bp.renesas.com Subject: Re: [PATCH v3 12/15] drm/bridge: Add ITE IT6263 LVDS to HDMI converter Message-ID: <20241022-wondrous-fractal-lion-aedcd9@houat> References: <20241021064446.263619-1-victor.liu@nxp.com> <20241021064446.263619-13-victor.liu@nxp.com> <20241021-thick-cockle-of-popularity-c5e28c@houat> <889594b9-e6cb-4d90-b959-cd0258b2f166@nxp.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha384; protocol="application/pgp-signature"; boundary="ndesq6xmp4pn532m" Content-Disposition: inline In-Reply-To: <889594b9-e6cb-4d90-b959-cd0258b2f166@nxp.com> --ndesq6xmp4pn532m Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH v3 12/15] drm/bridge: Add ITE IT6263 LVDS to HDMI converter MIME-Version: 1.0 On Tue, Oct 22, 2024 at 03:36:47PM +0800, Liu Ying wrote: > Hi Maxime, >=20 > On 10/21/2024, Maxime Ripard wrote: > > On Mon, Oct 21, 2024 at 02:44:43PM +0800, Liu Ying wrote: > >> +static int it6263_bridge_atomic_check(struct drm_bridge *bridge, > >> + struct drm_bridge_state *bridge_state, > >> + struct drm_crtc_state *crtc_state, > >> + struct drm_connector_state *conn_state) > >> +{ > >> + struct drm_display_mode *mode =3D &crtc_state->adjusted_mode; > >> + int ret; > >> + > >> + ret =3D drm_atomic_helper_connector_hdmi_check(conn_state->connector, > >> + conn_state->state); > >> + if (ret) > >> + return ret; > >> + > >> + return mode->clock > MAX_PIXEL_CLOCK_KHZ ? -EINVAL : 0; > >=20 > > drm_atomic_helper_connector_hdmi_check will already make that check, so > > it's redundant. >=20 > MAX_PIXEL_CLOCK_KHZ is 150MHz. With 150MHz pixel clock rate, we'll get > 150MHz HDMI character rate for 8bpc and 187.5MHz HDMI character rate > for 10bpc, both are lower than MAX_HDMI_TMDS_CHAR_RATE_HZ =3D 225MHz. I guess? I have no idea how that's relevant though. Where are those constraints coming from, and why aren't you checking for them in tmds_char_rate_valid? > So, it looks like pixel clock rate is the bottleneck. The bottleneck to what? > Remove drm_atomic_helper_connector_hdmi_check() or keep this as-is? No, like I said, remove the final check for mode->clock. Maxime --ndesq6xmp4pn532m Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iJUEABMJAB0WIQTkHFbLp4ejekA/qfgnX84Zoj2+dgUCZxdaCAAKCRAnX84Zoj2+ dkMtAX0bABUvvrQvsEVfC/FsHL24JniTnXVp5PfMg4bNoZgQKIMXrttSyJhmufST 5RbQcPUBfRss1fUSXSj1YNr6FqAGDfJUWa++ed7TSbFOKM1yWDyQJwOyznEzViOj kYYL52W9yg== =wUZL -----END PGP SIGNATURE----- --ndesq6xmp4pn532m--