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 5E62F8F5D for ; Sun, 16 Jul 2023 20:37:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD386C433C7; Sun, 16 Jul 2023 20:37:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1689539846; bh=DjDVurBA6rmSWngpAw4W7c7QhktxjztNTr2Dwm7SzAw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bHB62WPIo+9j/hlhZK6yCGIfVL46H9ygTRzMqaaEJdl1126+GCvlf/iYCPrety0+F AuuP7JLZBt35dEqwZ/wapan4sFu8jJ9EK56lAAP3mniywRAJeoZvjBx4Czj/vxYq5f h66mlojMh5hKUh3NPeHUvtps9Binr859x0OVb2Vw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Francesco Dolcini , Robert Foss , Sasha Levin Subject: [PATCH 6.1 152/591] drm/bridge: tc358768: fix TCLK_TRAILCNT computation Date: Sun, 16 Jul 2023 21:44:51 +0200 Message-ID: <20230716194927.798495956@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230716194923.861634455@linuxfoundation.org> References: <20230716194923.861634455@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Francesco Dolcini [ Upstream commit ee18698e212b1659dd0850d7e2ae0f22e16ed3d3 ] Correct computation of TCLK_TRAILCNT register. The driver does not implement non-continuous clock mode, so the actual value doesn't make a practical difference yet. However this change also ensures that the value does not write to reserved registers bits in case of under/overflow. This register must be set to a value that ensures that TCLK-TRAIL > 60ns and TEOT <= (105 ns + 12 x UI) with the actual value of TCLK-TRAIL being (TCLK_TRAILCNT + (1 to 2)) xHSByteClkCycle + (2 + (1 to 2)) * HSBYTECLKCycle - (PHY output delay) with PHY output delay being about (2 to 3) x MIPIBitClk cycle in the BitClk conversion. Fixes: ff1ca6397b1d ("drm/bridge: Add tc358768 driver") Signed-off-by: Francesco Dolcini Reviewed-by: Robert Foss Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-2-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-3-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-4-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-5-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-2-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-3-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-4-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-5-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-2-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-3-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-4-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-5-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-2-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-3-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-4-francesco@dolcini.it Link: https://patchwork.freedesktop.org/patch/msgid/20230427142934.55435-5-francesco@dolcini.it Signed-off-by: Sasha Levin --- drivers/gpu/drm/bridge/tc358768.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c index 8f7efb14ebdc7..822de6e356a2c 100644 --- a/drivers/gpu/drm/bridge/tc358768.c +++ b/drivers/gpu/drm/bridge/tc358768.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -640,6 +641,7 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) struct mipi_dsi_device *dsi_dev = priv->output.dev; unsigned long mode_flags = dsi_dev->mode_flags; u32 val, val2, lptxcnt, hact, data_type; + s32 raw_val; const struct drm_display_mode *mode; u32 dsibclk_nsk, dsiclk_nsk, ui_nsk, phy_delay_nsk; u32 dsiclk, dsibclk, video_start; @@ -751,9 +753,9 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) dev_dbg(priv->dev, "TCLK_HEADERCNT: 0x%x\n", val); tc358768_write(priv, TC358768_TCLK_HEADERCNT, val); - /* TCLK_TRAIL > 60ns + 3*UI */ - val = 60 + tc358768_to_ns(3 * ui_nsk); - val = tc358768_ns_to_cnt(val, dsibclk_nsk) - 5; + /* TCLK_TRAIL > 60ns AND TEOT <= 105 ns + 12*UI */ + raw_val = tc358768_ns_to_cnt(60 + tc358768_to_ns(2 * ui_nsk), dsibclk_nsk) - 5; + val = clamp(raw_val, 0, 127); dev_dbg(priv->dev, "TCLK_TRAILCNT: 0x%x\n", val); tc358768_write(priv, TC358768_TCLK_TRAILCNT, val); -- 2.39.2