From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.forwardemail.net (smtp.forwardemail.net [149.28.215.223]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D4576BFD2 for ; Sat, 15 Jun 2024 17:05:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=149.28.215.223 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718471124; cv=none; b=XriwRcVLfY5g8GPTZd7avHyRfdmXzhsNXlsOJZ5SqG9XQw9g2lZg7yWdN8a40fozA/lpexmu6bkJHtK0UI5bDM6UmeTGlwtP4uWDa6WDjdy6cj6SQ4Uuy2x8l1ufKE/iAFQyaVIM4hvqsB+FAMnPwk5oXGpEoSTbQ37Q7yK934I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718471124; c=relaxed/simple; bh=FaGxb6Oxbnm2wL0zClqTzPiAgKuIJ8QlVV/Emg9KgPc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dHubAT1rKhO7fFDghmiWMj2FkMiwBUwHO0MWfO0/q1kkvYT1Bisz3zSXd9l1WNVnzeHRNlBRej9z8FxcMBx8dDatvm0NnAkIV7wu8o/SABWrFtiF31QEHB9hFrRDQEZZdlWI+DJIxlzhQXB5/98Qd4hKg50Q9kZSVq4lEYDxtCQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kwiboo.se; spf=pass smtp.mailfrom=fe-bounces.kwiboo.se; dkim=pass (2048-bit key) header.d=kwiboo.se header.i=@kwiboo.se header.b=kgwOB6T9; arc=none smtp.client-ip=149.28.215.223 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kwiboo.se Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=fe-bounces.kwiboo.se Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kwiboo.se header.i=@kwiboo.se header.b="kgwOB6T9" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kwiboo.se; h=Content-Transfer-Encoding: MIME-Version: References: In-Reply-To: Message-ID: Date: Subject: Cc: To: From; q=dns/txt; s=fe-e1b5cab7be; t=1718471104; bh=edw+pFynRH27QoyX9zOhxiRHTMZh2GXeD3zDbH9aM0s=; b=kgwOB6T9ULzOyWUr9ARhoa84VHR8MpP83DdZtBKx7BfN70hCPCQoh6eKUUhtLaDgxmSiWxrNS mYMQeiPPyuYUlA9Gx9Bu+TYqJCNO60ThAs6sSNkbp/bL3/c3VQm6QCnNmcWHYGc0LKxzVDesT+l jaekM0HuQ0zlKSmOqsDobkxiUkz2GkIlRngHoQy7HNmUdMt69Mgc9lMLRinQwbaIZS4ecpnTfTO e+H4/8XTXH6R6BF3jAqaWsH99x1/DfxzZALnFqL07VOtZepSfkp27prRW6EnnWtgMj4h00yr1/k Q6xtONoLwuF3fVdChuopAvi+jGBGkM5ekYoE2ZNwTu+w== From: Jonas Karlman To: dri-devel@lists.freedesktop.org, Sandy Huang , "=?UTF-8?q?Heiko=20St=C3=BCbner?=" , Andy Yan , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter Cc: linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, Jonas Karlman , Yakir Yang Subject: [PATCH 08/13] drm/rockchip: dw_hdmi: Adjust cklvl & txlvl for RF/EMI Date: Sat, 15 Jun 2024 17:03:59 +0000 Message-ID: <20240615170417.3134517-9-jonas@kwiboo.se> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240615170417.3134517-1-jonas@kwiboo.se> References: <20240615170417.3134517-1-jonas@kwiboo.se> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Report-Abuse-To: abuse@forwardemail.net X-Report-Abuse: abuse@forwardemail.net X-Complaints-To: abuse@forwardemail.net X-ForwardEmail-Version: 0.4.40 X-ForwardEmail-Sender: rfc822; jonas@kwiboo.se, smtp.forwardemail.net, 149.28.215.223 X-ForwardEmail-ID: 666dc9bc24e0254b39804063 From: Yakir Yang Dut to the high HDMI signal voltage driver, Mickey have meet a serious RF/EMI problem, so we decided to reduce HDMI signal voltage to a proper value. The default params for phy is cklvl = 20 & txlvl = 13 (RF/EMI failed) ck: lvl = 13, term=100, vlo = 2.71, vhi=3.14, vswing = 0.43 tx: lvl = 20, term=100, vlo = 2.81, vhi=3.16, vswing = 0.35 1. We decided to reduce voltage value to lower, but VSwing still keep high, RF/EMI have been improved but still failed. ck: lvl = 6, term=100, vlo = 2.61, vhi=3.11, vswing = 0.50 tx: lvl = 6, term=100, vlo = 2.61, vhi=3.11, vswing = 0.50 2. We try to keep voltage value and vswing both lower, then RF/EMI test all passed ;) ck: lvl = 11, term= 66, vlo = 2.68, vhi=3.09, vswing = 0.40 tx: lvl = 11, term= 66, vlo = 2.68, vhi=3.09, vswing = 0.40 When we back to run HDMI different test and single-end test, we see different test passed, but signle-end test failed. The oscilloscope show that simgle-end clock's VL value is 1.78v (which remind LowLimit should not lower then 2.6v). 3. That's to say there are some different between PHY document and measure value. And according to experiment 2 results, we need to higher clock voltage and lower data voltage, then we can keep RF/EMI satisfied and single-end & differen test passed. ck: lvl = 9, term=100, vlo = 2.65, vhi=3.12, vswing = 0.47 tx: lvl = 16, term=100, vlo = 2.75, vhi=3.15, vswing = 0.39 Signed-off-by: Yakir Yang Signed-off-by: Jonas Karlman --- drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c index 4acf73b5692a..205cfe02079f 100644 --- a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c +++ b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c @@ -204,7 +204,7 @@ static const struct dw_hdmi_curr_ctrl rockchip_cur_ctr[] = { static const struct dw_hdmi_phy_config rockchip_phy_config[] = { /*pixelclk symbol term vlev*/ { 74250000, 0x8009, 0x0004, 0x0272}, - { 148500000, 0x802b, 0x0004, 0x028d}, + { 165000000, 0x802b, 0x0004, 0x0209}, { 297000000, 0x8039, 0x0005, 0x028d}, { ~0UL, 0x0000, 0x0000, 0x0000} }; -- 2.45.2