From patchwork Wed Jun 10 06:02:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sowjanya Komatineni X-Patchwork-Id: 207522 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 F37F6C433E0 for ; Wed, 10 Jun 2020 06:03:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE9A52083E for ; Wed, 10 Jun 2020 06:03:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="Tv2WFcOF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726403AbgFJGDj (ORCPT ); Wed, 10 Jun 2020 02:03:39 -0400 Received: from hqnvemgate25.nvidia.com ([216.228.121.64]:6113 "EHLO hqnvemgate25.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726112AbgFJGCy (ORCPT ); Wed, 10 Jun 2020 02:02:54 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate25.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Tue, 09 Jun 2020 23:02:08 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Tue, 09 Jun 2020 23:02:53 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Tue, 09 Jun 2020 23:02:53 -0700 Received: from HQMAIL111.nvidia.com (172.20.187.18) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Wed, 10 Jun 2020 06:02:53 +0000 Received: from hqnvemgw03.nvidia.com (10.124.88.68) by HQMAIL111.nvidia.com (172.20.187.18) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Wed, 10 Jun 2020 06:02:53 +0000 Received: from skomatineni-linux.nvidia.com (Not Verified[10.2.167.70]) by hqnvemgw03.nvidia.com with Trustwave SEG (v7, 5, 8, 10121) id ; Tue, 09 Jun 2020 23:02:53 -0700 From: Sowjanya Komatineni To: , , , , , , , CC: , , , , , , , Subject: [RFC PATCH v1 16/18] media: tegra-video: Compute settle times based on the clock rate Date: Tue, 9 Jun 2020 23:02:38 -0700 Message-ID: <1591768960-31648-17-git-send-email-skomatineni@nvidia.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1591768960-31648-1-git-send-email-skomatineni@nvidia.com> References: <1591768960-31648-1-git-send-email-skomatineni@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1591768928; bh=VN6FVs1l4xS3sEzG6E2hvQ8WglAefjSdk4oyRtTRSVY=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:X-NVConfidentiality:MIME-Version: Content-Type; b=Tv2WFcOFfKcbl9IVrO4IWAN9It1FicVs2C8hmMg5AabxRrFFEOraCzzFo9aZ5hB6w dmeuOa4enghNO4scnCuy+Wq4r6nxgXtl+7EPLrYRMkas0ZAL37WMg/Dj44undrsSa5 1XRWQPykd6WDHxBujpJWWldkmTsb5SlQdWuEHUwcRE4GsDyukkib9BPKq5OR4fjjy8 dHSQgChD1JkUbDfBCTckVRpMMCYUYQq9uDdVtiaGLo56HNlBHGLF6PBrtr8NyB0m44 Ae0ICBqORPLC7VJlqdSrIAh3rL47YfqzsT8Q2jtWmdPDbtVew69WiC9Kc7J6mps/Ms z4NYx4SDtdEQQ== Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Settle time determines the number of cil clock cyles to wait after LP00 when moving from LP to HS. This patch computes T-CLK-SETTLE and T-HS-SETTLE times based on cil clock rate and pixel rate from the sensor and programs them during streaming. T-CLK-SETTLE time is the interval during which receiver will ignore any HS transitions on clock lane starting from the beginning of T-CLK-PREPARE. T-HS-SETTLE time is the interval during which recevier will ignore any HS transitions on data lane starting from the beginning of T-HS-PREPARE. Signed-off-by: Sowjanya Komatineni --- drivers/staging/media/tegra-video/csi.c | 55 ++++++++++++++++++++++++++++ drivers/staging/media/tegra-video/csi.h | 5 +++ drivers/staging/media/tegra-video/tegra210.c | 17 ++++++++- 3 files changed, 75 insertions(+), 2 deletions(-) diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c index 82e340a..0f4d815 100644 --- a/drivers/staging/media/tegra-video/csi.c +++ b/drivers/staging/media/tegra-video/csi.c @@ -16,6 +16,8 @@ #include "csi.h" #include "video.h" +#define MHZ 1000000 + static inline struct tegra_csi * host1x_client_to_csi(struct host1x_client *client) { @@ -232,6 +234,59 @@ static int tegra_csi_g_frame_interval(struct v4l2_subdev *subdev, return 0; } +static unsigned int csi_get_pixel_rate(struct tegra_csi_channel *csi_chan) +{ + struct tegra_vi_channel *chan; + struct v4l2_subdev *src_subdev; + struct v4l2_ctrl *ctrl; + + chan = v4l2_get_subdev_hostdata(&csi_chan->subdev); + src_subdev = tegra_channel_get_remote_subdev(chan, true); + ctrl = v4l2_ctrl_find(src_subdev->ctrl_handler, V4L2_CID_PIXEL_RATE); + if (ctrl) + return v4l2_ctrl_g_ctrl_int64(ctrl); + + return 0; +} + +void tegra_csi_calc_settle_time(struct tegra_csi_channel *csi_chan, + u8 *clk_settle_time, + u8 *ths_settle_time) +{ + struct tegra_csi *csi = csi_chan->csi; + unsigned int cil_clk_mhz; + unsigned int pix_clk_mhz; + int clk_idx = (csi_chan->csi_port_num >> 1) + 1; + + cil_clk_mhz = clk_get_rate(csi->clks[clk_idx].clk) / MHZ; + pix_clk_mhz = csi_get_pixel_rate(csi_chan) / MHZ; + + /* + * CLK Settle time is the interval during which HS receiver should + * ignore any clock lane HS transitions, starting from the beginning + * of T-CLK-PREPARE. + * Per DPHY specification, T-CLK-SETTLE should be between 95ns ~ 300ns + * + * 95ns < (clk-settle-programmed + 7) * lp clk period < 300ns + * midpoint = 197.5 ns + */ + *clk_settle_time = ((95 + 300) * cil_clk_mhz - 14000) / 2000; + + /* + * THS Settle time is the interval during which HS receiver should + * ignore any data lane HS transitions, starting from the beginning + * of THS-PREPARE. + * + * Per DPHY specification, T-HS-SETTLE should be between 85ns + 6UI + * and 145ns+10UI. + * 85ns + 6UI < (Ths-settle-prog + 5) * lp_clk_period < 145ns + 10UI + * midpoint = 115ns + 8UI + */ + if (pix_clk_mhz) + *ths_settle_time = (115 * cil_clk_mhz + 8000 * cil_clk_mhz + / (2 * pix_clk_mhz) - 5000) / 1000; +} + static int tegra_csi_s_stream(struct v4l2_subdev *subdev, int enable) { struct tegra_vi_channel *chan = v4l2_get_subdev_hostdata(subdev); diff --git a/drivers/staging/media/tegra-video/csi.h b/drivers/staging/media/tegra-video/csi.h index 0e5a537..a52c7da1 100644 --- a/drivers/staging/media/tegra-video/csi.h +++ b/drivers/staging/media/tegra-video/csi.h @@ -52,6 +52,7 @@ struct tegra_csi; * @h_blank: horizontal blanking for TPG active format * @v_blank: vertical blanking for TPG active format * @mipi: mipi device for corresponding csi channel pads + * @pixel_rate: active pixel rate from the sensor on this channel */ struct tegra_csi_channel { struct list_head list; @@ -68,6 +69,7 @@ struct tegra_csi_channel { unsigned int h_blank; unsigned int v_blank; struct tegra_mipi_device *mipi; + unsigned int pixel_rate; }; /** @@ -148,4 +150,7 @@ extern const struct tegra_csi_soc tegra210_csi_soc; #endif void tegra_csi_error_recover(struct v4l2_subdev *subdev); +void tegra_csi_calc_settle_time(struct tegra_csi_channel *csi_chan, + u8 *clk_settle_time, + u8 *ths_settle_time); #endif diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c index 4f5080a..bcc0492 100644 --- a/drivers/staging/media/tegra-video/tegra210.c +++ b/drivers/staging/media/tegra-video/tegra210.c @@ -7,6 +7,7 @@ * This source file contains Tegra210 supported video formats, * VI and CSI SoC specific data, operations and registers accessors. */ +#include #include #include #include @@ -98,6 +99,8 @@ #define BRICK_CLOCK_B_4X (0x2 << 16) #define TEGRA_CSI_CIL_PAD_CONFIG1 0x004 #define TEGRA_CSI_CIL_PHY_CONTROL 0x008 +#define CLK_SETTLE_MASK GENMASK(13, 8) +#define THS_SETTLE_MASK GENMASK(5, 0) #define TEGRA_CSI_CIL_INTERRUPT_MASK 0x00c #define TEGRA_CSI_CIL_STATUS 0x010 #define TEGRA_CSI_CILX_STATUS 0x014 @@ -770,8 +773,14 @@ static int tegra210_csi_start_streaming(struct tegra_csi_channel *csi_chan) { struct tegra_csi *csi = csi_chan->csi; unsigned int portno = csi_chan->csi_port_num; + u8 clk_settle_time = 0; + u8 ths_settle_time = 10; u32 val; + if (!csi_chan->pg_mode) + tegra_csi_calc_settle_time(csi_chan, &clk_settle_time, + &ths_settle_time); + csi_write(csi, portno, TEGRA_CSI_CLKEN_OVERRIDE, 0); /* clean up status */ @@ -782,7 +791,9 @@ static int tegra210_csi_start_streaming(struct tegra_csi_channel *csi_chan) /* CIL PHY registers setup */ cil_write(csi, portno, TEGRA_CSI_CIL_PAD_CONFIG0, 0x0); - cil_write(csi, portno, TEGRA_CSI_CIL_PHY_CONTROL, 0xa); + cil_write(csi, portno, TEGRA_CSI_CIL_PHY_CONTROL, + FIELD_PREP(CLK_SETTLE_MASK, clk_settle_time) | + FIELD_PREP(THS_SETTLE_MASK, ths_settle_time)); /* * The CSI unit provides for connection of up to six cameras in @@ -801,7 +812,9 @@ static int tegra210_csi_start_streaming(struct tegra_csi_channel *csi_chan) BRICK_CLOCK_A_4X); cil_write(csi, portno + 1, TEGRA_CSI_CIL_PAD_CONFIG0, 0x0); cil_write(csi, portno + 1, TEGRA_CSI_CIL_INTERRUPT_MASK, 0x0); - cil_write(csi, portno + 1, TEGRA_CSI_CIL_PHY_CONTROL, 0xa); + cil_write(csi, portno + 1, TEGRA_CSI_CIL_PHY_CONTROL, + FIELD_PREP(CLK_SETTLE_MASK, clk_settle_time) | + FIELD_PREP(THS_SETTLE_MASK, ths_settle_time)); csi_write(csi, portno, TEGRA_CSI_PHY_CIL_COMMAND, CSI_A_PHY_CIL_ENABLE | CSI_B_PHY_CIL_ENABLE); } else {