From patchwork Mon Jul 11 11:05:39 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yakir Yang X-Patchwork-Id: 9223335 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9EE6C604DB for ; Mon, 11 Jul 2016 11:07:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8EF7C27BFF for ; Mon, 11 Jul 2016 11:07:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 83AB927CCB; Mon, 11 Jul 2016 11:07:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 312B427BFF for ; Mon, 11 Jul 2016 11:07:21 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bMZ2U-0007X3-5m; Mon, 11 Jul 2016 11:06:14 +0000 Received: from lucky1.263xmail.com ([211.157.147.135]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bMZ2L-0007Nl-Gi; Mon, 11 Jul 2016 11:06:06 +0000 Received: from ykk?rock-chips.com (unknown [192.168.167.234]) by lucky1.263xmail.com (Postfix) with SMTP id BA3B76E5; Mon, 11 Jul 2016 19:05:41 +0800 (CST) X-263anti-spam: KSV:0; X-MAIL-GRAY: 1 X-MAIL-DELIVERY: 0 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-ADDR-CHECKED: 0 Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.263.net (Postfix) with ESMTP id 597D75005; Mon, 11 Jul 2016 19:05:39 +0800 (CST) X-RL-SENDER: ykk@rock-chips.com X-FST-TO: mark.yao@rock-chips.com X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: ykk@rock-chips.com X-UNIQUE-TAG: <61492dfc8b0e96926c6764c3049b7f85> X-ATTACHMENT-NUM: 0 X-SENDER: ykk@rock-chips.com X-DNS-TYPE: 0 Received: from localhost.localdomain (unknown [58.22.7.114]) by smtp.263.net (Postfix) whith ESMTP id 11623RMXBDK; Mon, 11 Jul 2016 19:05:41 +0800 (CST) From: Yakir Yang To: Mark Yao , Heiko Stuebner , Rob Herring , Russell King , Philipp Zabel , Andy Yan Subject: [PATCH v1 2/6] drm/rockchip: dw_hdmi: adjust cklvl & txlvl for RF/EMI Date: Mon, 11 Jul 2016 19:05:39 +0800 Message-Id: <1468235139-29460-1-git-send-email-ykk@rock-chips.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1468235079-29152-1-git-send-email-ykk@rock-chips.com> References: <1468235079-29152-1-git-send-email-ykk@rock-chips.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160711_040606_025550_D06A69CD X-CRM114-Status: UNSURE ( 7.40 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, David Airlie , Daniel Vetter , Yakir Yang , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, Kumar Gala , xhc@rock-chips.com, linux-arm-kernel@lists.infradead.org, Zheng Yang MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP 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 Reviewed-by: Douglas Anderson --- 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 a621118..cdb63ac 100644 --- a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c +++ b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c @@ -124,7 +124,7 @@ 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} };