From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6C028ECDE47 for ; Mon, 5 Nov 2018 10:45:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3CB4720882 for ; Mon, 5 Nov 2018 10:45:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3CB4720882 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729108AbeKEUEJ (ORCPT ); Mon, 5 Nov 2018 15:04:09 -0500 Received: from mail.bootlin.com ([62.4.15.54]:33573 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726255AbeKEUEI (ORCPT ); Mon, 5 Nov 2018 15:04:08 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id C3488207B0; Mon, 5 Nov 2018 11:45:02 +0100 (CET) Received: from localhost (unknown [185.94.189.188]) by mail.bootlin.com (Postfix) with ESMTPSA id 49585208DC; Mon, 5 Nov 2018 11:44:36 +0100 (CET) Date: Mon, 5 Nov 2018 11:44:36 +0100 From: Maxime Ripard To: Jagan Teki Cc: Maarten Lankhorst , Sean Paul , David Airlie , Rob Herring , Chen-Yu Tsai , Icenowy Zheng , Jernej Skrabec , Vasily Khoruzhick , Thierry Reding , Mark Rutland , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Michael Trimarchi , TL Lim , linux-sunxi@googlegroups.com Subject: Re: [PATCH 04/10] drm/sun4i: sun6i_mipi_dsi: Setup burst mode Message-ID: <20181105104436.mt7r2ln2lay5sfl5@flea> References: <20181103100900.30313-1-jagan@amarulasolutions.com> <20181103100900.30313-5-jagan@amarulasolutions.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="lojmyyjyfhxs6yu5" Content-Disposition: inline In-Reply-To: <20181103100900.30313-5-jagan@amarulasolutions.com> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --lojmyyjyfhxs6yu5 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Nov 03, 2018 at 03:38:54PM +0530, Jagan Teki wrote: > Setting up burst mode display would require to compute > - Horizontal timing edge values to fill burst drq register > - Line, sync values to fill burst line register >=20 > Since there is no direct documentation for these computations > the edge and line formulas are taken from BSP code > (in drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c) > line_num =3D panel->lcd_ht*dsi_pixel_bits[panel->lcd_dsi_format]/ > (8*panel->lcd_dsi_lane); > edge1 =3D sync_point+(panel->lcd_x+panel->lcd_hbp+20)* > dsi_pixel_bits[panel->lcd_dsi_format] /(8*panel->lcd_dsi_lane); > edge1 =3D (edge1>line_num)?line_num:edge1; > edge0 =3D edge1+(panel->lcd_x+40)*tcon_div/8; > edge0 =3D (edge0>line_num)?(edge0-line_num):1; >=20 > Signed-off-by: Jagan Teki > --- > drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 48 +++++++++++++++++++++----- > 1 file changed, 40 insertions(+), 8 deletions(-) >=20 > diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun= 4i/sun6i_mipi_dsi.c > index 4965b2c71e4c..b6c01891df36 100644 > --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c > @@ -375,20 +375,52 @@ static void sun6i_dsi_setup_burst(struct sun6i_dsi = *dsi, > struct drm_display_mode *mode) > { > struct mipi_dsi_device *device =3D dsi->device; > + unsigned int Bpp =3D mipi_dsi_pixel_format_to_bpp(device->format); > + u32 line_num, edge0, edge1, hact_sync_bp; > + u32 sync_point, tcon_div; > u32 val =3D 0; > =20 > - if ((mode->hsync_start - mode->hdisplay) > 20) { > - /* Maaaaaagic */ > - u16 drq =3D (mode->hsync_start - mode->hdisplay) - 20; > + if (device->mode_flags !=3D MIPI_DSI_MODE_VIDEO_BURST) { > + if ((mode->hsync_start - mode->hdisplay) > 20) { > + /* Maaaaaagic */ > + u16 drq =3D (mode->hsync_start - mode->hdisplay) - 20; > =20 > - drq *=3D mipi_dsi_pixel_format_to_bpp(device->format); > - drq /=3D 32; > + drq *=3D Bpp; > + drq /=3D 32; > =20 > - val =3D (SUN6I_DSI_TCON_DRQ_ENABLE_MODE | > - SUN6I_DSI_TCON_DRQ_SET(drq)); > + val =3D (SUN6I_DSI_TCON_DRQ_ENABLE_MODE | > + SUN6I_DSI_TCON_DRQ_SET(drq)); > + } > + > + regmap_write(dsi->regs, SUN6I_DSI_TCON_DRQ_REG, val); > + > + return; > } Having functions to compute drq, the line_number and so on would help the readibility a lot. > - regmap_write(dsi->regs, SUN6I_DSI_TCON_DRQ_REG, val); > + sync_point =3D 40; > + tcon_div =3D 8; /* FIXME need to retrive the divider from TCON */ Then do it. Especially since you have exactly 0 guarantee of the divider being 8. (also, s/retrive/retrieve/) > + > + line_num =3D mode->htotal * Bpp / (8 * device->lanes); > + /* Horizental timings duration excluding front porch */ Horizontal Maxime --=20 Maxime Ripard, Bootlin Embedded Linux and Kernel engineering https://bootlin.com --lojmyyjyfhxs6yu5 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCW+AfFAAKCRDj7w1vZxhR xSyYAQDhsuhDv90BqYdcm8sWRykRSClHY4Pn3NZuAd95qwM7AgEAkWBhm0e80GzZ Q7UBCEBhHsjbPP842JgOu2Z3+/H8/Ao= =ZGoQ -----END PGP SIGNATURE----- --lojmyyjyfhxs6yu5--