From patchwork Mon May 18 18:47:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11556107 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F13F6913 for ; Mon, 18 May 2020 18:47:43 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CFDD22070A for ; Mon, 18 May 2020 18:47:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Wx0bS0pt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CFDD22070A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D68336E489; Mon, 18 May 2020 18:47:39 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-pl1-x643.google.com (mail-pl1-x643.google.com [IPv6:2607:f8b0:4864:20::643]) by gabe.freedesktop.org (Postfix) with ESMTPS id 92F206E489 for ; Mon, 18 May 2020 18:47:38 +0000 (UTC) Received: by mail-pl1-x643.google.com with SMTP id q16so4602514plr.2 for ; Mon, 18 May 2020 11:47:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=fI9/Coy2jHU24hv3APejJ/BFCoipYPisETaqwXZO4ww=; b=Wx0bS0ptDbThH06HCY0b1DBY2CcuHMoNlOElrVm8xW7XiC+ldEXxJH8tuZKYr9nHut XrzWPXrLPMmTRrsYhiO6C97bnWtz5QJubocZPZmSynQkozHiwSQJ9u8CcWZcho2f8V2M NncIB27kIHIR7LNvbIuihEXs2fQgdx8pnEYlQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=fI9/Coy2jHU24hv3APejJ/BFCoipYPisETaqwXZO4ww=; b=HPFvcy2K7kMBfpHZa8RMKrrPjkfbw7+U1soC9RWmYY9kj6L3M4JFL+pg7p1i7JOHAy udFFhkljMPIDuJUnSbossdErOlmEBDX7RqBNcHbO3eU/A5CSxOIKkQB13Uq7HJCgHLzC KYiURQtmR9w2FSvKGnMQs5U5WeCX9mwxxd9FHvnxLlogJM/FUtPkjk/Kbo/m6a7X7qsW 8/9X2MUoXhZZFSPTkHBroDhICSM4ccZqOTZuctgztvR3bh170kRFp//1sGZxDm4C9ooe 7FVXvUb6EqpMpLlTkfWddLhSpL6yFq2/ZQJqmPhXTrcgxFQVynFc3zlb2CjUJydsZ4yC 2EzA== X-Gm-Message-State: AOAM531Kq7tCddxDzqBFw5Z7XRiZlPFBC3V9oyd7qXCVnbkGAidtHKGM 7lXiR38iF4MjGLGxm6kJaKmkLw== X-Google-Smtp-Source: ABdhPJzq4lauJpJkoub5/jaKiCGMylfupnMDHNkDWGZnlKDqbU8PYXnVGgLx0sxltYZyEvgnmNutQQ== X-Received: by 2002:a17:90a:ee85:: with SMTP id i5mr767777pjz.165.1589827658054; Mon, 18 May 2020 11:47:38 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id s136sm9302719pfc.29.2020.05.18.11.47.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 May 2020 11:47:37 -0700 (PDT) From: Douglas Anderson To: Sam Ravnborg , Andrzej Hajda , Neil Armstrong , Laurent Pinchart Subject: [REPOST PATCH v2] drm/bridge: ti-sn65dsi86: Implement lane reordering + polarity Date: Mon, 18 May 2020 11:47:17 -0700 Message-Id: <20200518114656.REPOST.v2.1.Ibc8eeddcee94984a608d6900b46f9ffde4045da4@changeid> X-Mailer: git-send-email 2.26.2.761.g0e0b3e54be-goog MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: robdclark@chromium.org, Jernej Skrabec , Jonas Karlman , David Airlie , linux-arm-msm@vger.kernel.org, Douglas Anderson , dri-devel@lists.freedesktop.org, swboyd@chromium.org, seanpaul@chromium.org, linux-kernel@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The ti-sn65dsi86 MIPI DSI to eDP bridge chip supports arbitrary remapping of eDP lanes and also polarity inversion. Both of these features have been described in the device tree bindings for the device since the beginning but were never implemented in the driver. Implement both of them. Part of this change also allows you to (via the same device tree bindings) specify to use fewer than the max number of DP lanes that the panel reports. This could be useful if your display supports more lanes but only a few are hooked up on your board. Signed-off-by: Douglas Anderson Reviewed-by: Stephen Boyd Reviewed-by: Rob Clark --- Re-posting patch v2, patch #1. I added tags and put Sam in the "To" list. Patch #2 was dropped since it was squashed elsewhere. This now applies to the top of drm-misc-next. Changes in v2: - Use SN_MAX_DP_LANES instead of 4 in one place. - Comment that we aren't doing full validation of dts params. - Check dp_lanes <= SN_MAX_DP_LANES to avoid buffer overrun. - Add missing of_node_put() drivers/gpu/drm/bridge/ti-sn65dsi86.c | 82 ++++++++++++++++++++++----- 1 file changed, 68 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c index 1855fb9f09f2..2240e9973178 100644 --- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c +++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c @@ -50,8 +50,12 @@ #define SN_CHA_VERTICAL_BACK_PORCH_REG 0x36 #define SN_CHA_HORIZONTAL_FRONT_PORCH_REG 0x38 #define SN_CHA_VERTICAL_FRONT_PORCH_REG 0x3A +#define SN_LN_ASSIGN_REG 0x59 +#define LN_ASSIGN_WIDTH 2 #define SN_ENH_FRAME_REG 0x5A #define VSTREAM_ENABLE BIT(3) +#define LN_POLRS_OFFSET 4 +#define LN_POLRS_MASK 0xf0 #define SN_DATA_FORMAT_REG 0x5B #define BPP_18_RGB BIT(0) #define SN_HPD_DISABLE_REG 0x5C @@ -98,6 +102,7 @@ #define SN_REGULATOR_SUPPLY_NUM 4 +#define SN_MAX_DP_LANES 4 #define SN_NUM_GPIOS 4 #define SN_GPIO_PHYSICAL_OFFSET 1 @@ -116,6 +121,8 @@ * @enable_gpio: The GPIO we toggle to enable the bridge. * @supplies: Data for bulk enabling/disabling our regulators. * @dp_lanes: Count of dp_lanes we're using. + * @ln_assign: Value to program to the LN_ASSIGN register. + * @ln_polr: Value for the 4-bit LN_POLRS field of SN_ENH_FRAME_REG. * * @gchip: If we expose our GPIOs, this is used. * @gchip_output: A cache of whether we've set GPIOs to output. This @@ -141,6 +148,8 @@ struct ti_sn_bridge { struct gpio_desc *enable_gpio; struct regulator_bulk_data supplies[SN_REGULATOR_SUPPLY_NUM]; int dp_lanes; + u8 ln_assign; + u8 ln_polrs; struct gpio_chip gchip; DECLARE_BITMAP(gchip_output, SN_NUM_GPIOS); @@ -708,26 +717,20 @@ static void ti_sn_bridge_enable(struct drm_bridge *bridge) int dp_rate_idx; unsigned int val; int ret = -EINVAL; + int max_dp_lanes; - /* - * Run with the maximum number of lanes that the DP sink supports. - * - * Depending use cases, we might want to revisit this later because: - * - It's plausible that someone may have run fewer lines to the - * sink than the sink actually supports, assuming that the lines - * will just be driven at a higher rate. - * - The DP spec seems to indicate that it's more important to minimize - * the number of lanes than the link rate. - * - * If we do revisit, it would be important to measure the power impact. - */ - pdata->dp_lanes = ti_sn_get_max_lanes(pdata); + max_dp_lanes = ti_sn_get_max_lanes(pdata); + pdata->dp_lanes = min(pdata->dp_lanes, max_dp_lanes); /* DSI_A lane config */ - val = CHA_DSI_LANES(4 - pdata->dsi->lanes); + val = CHA_DSI_LANES(SN_MAX_DP_LANES - pdata->dsi->lanes); regmap_update_bits(pdata->regmap, SN_DSI_LANES_REG, CHA_DSI_LANES_MASK, val); + regmap_write(pdata->regmap, SN_LN_ASSIGN_REG, pdata->ln_assign); + regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, LN_POLRS_MASK, + pdata->ln_polrs << LN_POLRS_OFFSET); + /* set dsi clk frequency value */ ti_sn_bridge_set_dsi_rate(pdata); @@ -1089,6 +1092,55 @@ static int ti_sn_setup_gpio_controller(struct ti_sn_bridge *pdata) return ret; } +static void ti_sn_bridge_parse_lanes(struct ti_sn_bridge *pdata, + struct device_node *np) +{ + u32 lane_assignments[SN_MAX_DP_LANES] = { 0, 1, 2, 3 }; + u32 lane_polarities[SN_MAX_DP_LANES] = { }; + struct device_node *endpoint; + u8 ln_assign = 0; + u8 ln_polrs = 0; + int dp_lanes; + int i; + + /* + * Read config from the device tree about lane remapping and lane + * polarities. These are optional and we assume identity map and + * normal polarity if nothing is specified. It's OK to specify just + * data-lanes but not lane-polarities but not vice versa. + * + * Error checking is light (we just make sure we don't crash or + * buffer overrun) and we assume dts is well formed and specifying + * mappings that the hardware supports. + */ + endpoint = of_graph_get_endpoint_by_regs(np, 1, -1); + dp_lanes = of_property_count_u32_elems(endpoint, "data-lanes"); + if (dp_lanes > 0 && dp_lanes <= SN_MAX_DP_LANES) { + of_property_read_u32_array(endpoint, "data-lanes", + lane_assignments, dp_lanes); + of_property_read_u32_array(endpoint, "lane-polarities", + lane_polarities, dp_lanes); + } else { + dp_lanes = SN_MAX_DP_LANES; + } + of_node_put(endpoint); + + /* + * Convert into register format. Loop over all lanes even if + * data-lanes had fewer elements so that we nicely initialize + * the LN_ASSIGN register. + */ + for (i = SN_MAX_DP_LANES - 1; i >= 0; i--) { + ln_assign = ln_assign << LN_ASSIGN_WIDTH | lane_assignments[i]; + ln_polrs = ln_polrs << 1 | lane_polarities[i]; + } + + /* Stash in our struct for when we power on */ + pdata->dp_lanes = dp_lanes; + pdata->ln_assign = ln_assign; + pdata->ln_polrs = ln_polrs; +} + static int ti_sn_bridge_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -1131,6 +1183,8 @@ static int ti_sn_bridge_probe(struct i2c_client *client, return ret; } + ti_sn_bridge_parse_lanes(pdata, client->dev.of_node); + ret = ti_sn_bridge_parse_regulators(pdata); if (ret) { DRM_ERROR("failed to parse regulators\n");