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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADAE3C7619A for ; Sun, 2 Apr 2023 10:55:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230411AbjDBKzW (ORCPT ); Sun, 2 Apr 2023 06:55:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229503AbjDBKzR (ORCPT ); Sun, 2 Apr 2023 06:55:17 -0400 Received: from mout-p-101.mailbox.org (mout-p-101.mailbox.org [IPv6:2001:67c:2050:0:465::101]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 63E5D1A975 for ; Sun, 2 Apr 2023 03:55:15 -0700 (PDT) Received: from smtp102.mailbox.org (smtp102.mailbox.org [10.196.197.102]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-101.mailbox.org (Postfix) with ESMTPS id 4Pq9sW6T1fz9sVx; Sun, 2 Apr 2023 12:55:11 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oltmanns.dev; s=MBO0001; t=1680432911; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=JGmLL2lif/lN1JO6yxqqMUbCCQ09GzfW7zKPJU5P/qA=; b=B53XDWj8eAlOkkTpZqQh0vAT+uK+slZGNpNqeRmmbjiB3J0NWX56+wQF62EussCLl8zDKW m5KnuZ10WixAhM111aPX4gVET5pbzPjBITADUpWWIKjCERRQ1aaYprjCcV/52/JU5MoJnS L36CnY7LVREDx/PR8iugWLYT3S0LJspLg3zL2XdpOyCjVNui/7ktJX3Yhra0kav6S9cxch +WENgzLr/+iVvFculnbm2sloiGCTYMSy7NWFFZtOcaHvMMEdXySRz6j2S3vhCiiemUv4Wc HZpDlHWIaPqv8k/NE7QWye0VOaZjmUWS0+WM7cVPf4eC4oGqS/gVtYTF45DEbA== References: <20230331110245.43527-1-me@crly.cz> <20230331110245.43527-4-me@crly.cz> From: Frank Oltmanns To: Roman Beranek Cc: Maxime Ripard , Chen-Yu Tsai , David Airlie , Daniel Vetter , Jernej Skrabec , Samuel Holland , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] drm: sun4i: calculate proper DCLK rate for DSI Date: Sun, 02 Apr 2023 12:49:08 +0200 In-reply-to: <20230331110245.43527-4-me@crly.cz> Message-ID: <87h6tya70h.fsf@oltmanns.dev> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Roman, On 2023-03-31 at 13:02:45 +0200, Roman Beranek wrote: > In DSI mode, TCON0's data clock is required to run at 1/4 the per-lane > bit rate. > > Signed-off-by: Roman Beranek > --- > drivers/gpu/drm/sun4i/sun4i_tcon.c | 36 +++++++++++++++++------------- > 1 file changed, 21 insertions(+), 15 deletions(-) > > diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c > index eec26b1faa4b..b263de7a8237 100644 > --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c > +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c > @@ -291,18 +291,6 @@ static int sun4i_tcon_get_clk_delay(const struct drm_display_mode *mode, > return delay; > } > > -static void sun4i_tcon0_mode_set_common(struct sun4i_tcon *tcon, > - const struct drm_display_mode *mode) > -{ > - /* Configure the dot clock */ > - clk_set_rate(tcon->dclk, mode->crtc_clock * 1000); > - > - /* Set the resolution */ > - regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG, > - SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) | > - SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay)); > -} > - > static void sun4i_tcon0_mode_set_dithering(struct sun4i_tcon *tcon, > const struct drm_connector *connector) > { > @@ -367,10 +355,18 @@ static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon, > u32 block_space, start_delay; > u32 tcon_div; > > + /* > + * dclk is required to run at 1/4 the DSI per-lane bit rate. > + */ > tcon->dclk_min_div = SUN6I_DSI_TCON_DIV; > tcon->dclk_max_div = SUN6I_DSI_TCON_DIV; > + clk_set_rate(tcon->dclk, mode->crtc_clock * 1000 * (bpp / lanes) > + / SUN6I_DSI_TCON_DIV); When apply this to drm-next my panel stays dark. I haven't figured out yet why, though. The other two patches in this series work fine, i.e. they have no effect as they are just a refactoring. I'm testing this on my pinephone. It's the same with the patch I submitted. For whatever reason, it no longer works on drm-next. At the time I'm writing this, drm-next is at 82bbec189ab3 "Merge v6.3-rc4 into drm-next". Does it work for you? And if so, on which commit are you basing this series? Thanks, Frank > > - sun4i_tcon0_mode_set_common(tcon, mode); > + /* Set the resolution */ > + regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG, > + SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) | > + SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay)); > > /* Set dithering if needed */ > sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder)); > @@ -438,7 +434,12 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon, > > tcon->dclk_min_div = 7; > tcon->dclk_max_div = 7; > - sun4i_tcon0_mode_set_common(tcon, mode); > + clk_set_rate(tcon->dclk, mode->crtc_clock * 1000); > + > + /* Set the resolution */ > + regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG, > + SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) | > + SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay)); > > /* Set dithering if needed */ > sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder)); > @@ -515,7 +516,12 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon, > > tcon->dclk_min_div = tcon->quirks->dclk_min_div; > tcon->dclk_max_div = 127; > - sun4i_tcon0_mode_set_common(tcon, mode); > + clk_set_rate(tcon->dclk, mode->crtc_clock * 1000); > + > + /* Set the resolution */ > + regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG, > + SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) | > + SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay)); > > /* Set dithering if needed */ > sun4i_tcon0_mode_set_dithering(tcon, connector); -- -- Frank Oltmanns