From patchwork Tue Mar 26 10:31:39 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomi Valkeinen X-Patchwork-Id: 10870861 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5EAF11575 for ; Tue, 26 Mar 2019 10:33:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4906C28FFE for ; Tue, 26 Mar 2019 10:33:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3BA5F29018; Tue, 26 Mar 2019 10:33:27 +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=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B6A7028FFE for ; Tue, 26 Mar 2019 10:33:26 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 551606E7F3; Tue, 26 Mar 2019 10:33:22 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from lelv0143.ext.ti.com (lelv0143.ext.ti.com [198.47.23.248]) by gabe.freedesktop.org (Postfix) with ESMTPS id 627BC6E7F0 for ; Tue, 26 Mar 2019 10:33:13 +0000 (UTC) Received: from lelv0266.itg.ti.com ([10.180.67.225]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id x2QAXAGf086595; Tue, 26 Mar 2019 05:33:10 -0500 Received: from DLEE103.ent.ti.com (dlee103.ent.ti.com [157.170.170.33]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x2QAXAbA003320 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 26 Mar 2019 05:33:10 -0500 Received: from DLEE105.ent.ti.com (157.170.170.35) by DLEE103.ent.ti.com (157.170.170.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Tue, 26 Mar 2019 05:33:05 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DLEE105.ent.ti.com (157.170.170.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5 via Frontend Transport; Tue, 26 Mar 2019 05:33:05 -0500 Received: from deskari.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id x2QAWN2H071249; Tue, 26 Mar 2019 05:33:03 -0500 From: Tomi Valkeinen To: Andrzej Hajda , Laurent Pinchart , , Lucas Stach , Andrey Gusakov , Philipp Zabel , Andrey Smirnov , Jyri Sarha , Peter Ujfalusi , Benoit Parrot Subject: [PATCHv2 15/22] drm/bridge: tc358767: clean-up link training Date: Tue, 26 Mar 2019 12:31:39 +0200 Message-ID: <20190326103146.24795-16-tomi.valkeinen@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190326103146.24795-1-tomi.valkeinen@ti.com> References: <20190326103146.24795-1-tomi.valkeinen@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1553596390; bh=obAY8AyHfzzWP8mtXrDAZNmMCcmZJ9004aENP2tc+g4=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=XppdJtfC2XulE+eyJ+41EUBHQJEVlG7+KvhUfHxdHmdPgv8JsWjDlgMAmg6i0aTaP wt+HaP8azaxzpKG8oIRvRTB6jDoUOu/UVSrFtZWVKeKm3Ismu6ssr8jQZytyLV68Gy Wmb1oWsZUBkvZt2lZx66YDV8QOCQO74RSpb1ux6g= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tomi Valkeinen Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The current link training code does unnecessary retry-loops, and does extra writes to the registers. It is easier to follow the flow and ensure it's similar to Toshiba's documentation if we deal with LT inside tc_main_link_enable() function. This patch adds tc_wait_link_training() which handles waiting for the LT phase to finish, and does the necessary LT register setups in tc_main_link_enable, without extra loops. Signed-off-by: Tomi Valkeinen Reviewed-by: Andrzej Hajda --- drivers/gpu/drm/bridge/tc358767.c | 129 +++++++++++++----------------- 1 file changed, 57 insertions(+), 72 deletions(-) diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c index 220408db82f7..1c61f6205e43 100644 --- a/drivers/gpu/drm/bridge/tc358767.c +++ b/drivers/gpu/drm/bridge/tc358767.c @@ -740,83 +740,25 @@ static int tc_set_video_mode(struct tc_data *tc, return ret; } -static int tc_link_training(struct tc_data *tc, int pattern) +static int tc_wait_link_training(struct tc_data *tc, u32 *error) { - const char * const *errors; - u32 srcctrl = tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS | - DP0_SRCCTRL_AUTOCORRECT; - int timeout; - int retry; + u32 timeout = 1000; u32 value; int ret; - if (pattern == DP_TRAINING_PATTERN_1) { - srcctrl |= DP0_SRCCTRL_TP1; - errors = training_pattern1_errors; - } else { - srcctrl |= DP0_SRCCTRL_TP2; - errors = training_pattern2_errors; - } - - /* Set DPCD 0x102 for Training Part 1 or 2 */ - tc_write(DP0_SNKLTCTRL, DP_LINK_SCRAMBLING_DISABLE | pattern); - - tc_write(DP0_LTLOOPCTRL, - (0x0f << 28) | /* Defer Iteration Count */ - (0x0f << 24) | /* Loop Iteration Count */ - (0x0d << 0)); /* Loop Timer Delay */ - - retry = 5; do { - /* Set DP0 Training Pattern */ - tc_write(DP0_SRCCTRL, srcctrl); - - /* Enable DP0 to start Link Training */ - tc_write(DP0CTL, DP_EN); - - /* wait */ - timeout = 1000; - do { - tc_read(DP0_LTSTAT, &value); - udelay(1); - } while ((!(value & LT_LOOPDONE)) && (--timeout)); - if (timeout == 0) { - dev_err(tc->dev, "Link training timeout!\n"); - } else { - int pattern = (value >> 11) & 0x3; - int error = (value >> 8) & 0x7; - - dev_dbg(tc->dev, - "Link training phase %d done after %d uS: %s\n", - pattern, 1000 - timeout, errors[error]); - if (pattern == DP_TRAINING_PATTERN_1 && error == 0) - break; - if (pattern == DP_TRAINING_PATTERN_2) { - value &= LT_CHANNEL1_EQ_BITS | - LT_INTERLANE_ALIGN_DONE | - LT_CHANNEL0_EQ_BITS; - /* in case of two lanes */ - if ((tc->link.base.num_lanes == 2) && - (value == (LT_CHANNEL1_EQ_BITS | - LT_INTERLANE_ALIGN_DONE | - LT_CHANNEL0_EQ_BITS))) - break; - /* in case of one line */ - if ((tc->link.base.num_lanes == 1) && - (value == (LT_INTERLANE_ALIGN_DONE | - LT_CHANNEL0_EQ_BITS))) - break; - } - } - /* restart */ - tc_write(DP0CTL, 0); - usleep_range(10, 20); - } while (--retry); - if (retry == 0) { - dev_err(tc->dev, "Failed to finish training phase %d\n", - pattern); + udelay(1); + tc_read(DP0_LTSTAT, &value); + } while ((!(value & LT_LOOPDONE)) && (--timeout)); + + if (timeout == 0) { + dev_err(tc->dev, "Link training timeout waiting for LT_LOOPDONE!\n"); + ret = -ETIMEDOUT; + goto err; } + *error = (value >> 8) & 0x7; + return 0; err: return ret; @@ -832,6 +774,7 @@ static int tc_main_link_enable(struct tc_data *tc) u32 value; int ret; u8 tmp[8]; + u32 error; /* display mode should be set at this point */ if (!tc->mode) @@ -950,14 +893,56 @@ static int tc_main_link_enable(struct tc_data *tc) if (ret < 0) goto err_dpcd_write; - ret = tc_link_training(tc, DP_TRAINING_PATTERN_1); + /* LINK TRAINING PATTERN 1 */ + + /* Set DPCD 0x102 for Training Pattern 1 */ + tc_write(DP0_SNKLTCTRL, DP_LINK_SCRAMBLING_DISABLE | DP_TRAINING_PATTERN_1); + + tc_write(DP0_LTLOOPCTRL, + (15 << 28) | /* Defer Iteration Count */ + (15 << 24) | /* Loop Iteration Count */ + (0xd << 0)); /* Loop Timer Delay */ + + tc_write(DP0_SRCCTRL, tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS | DP0_SRCCTRL_AUTOCORRECT | + DP0_SRCCTRL_TP1); + + /* Enable DP0 to start Link Training */ + tc_write(DP0CTL, + ((tc->link.base.capabilities & DP_LINK_CAP_ENHANCED_FRAMING) ? EF_EN : 0) | + DP_EN); + + /* wait */ + ret = tc_wait_link_training(tc, &error); if (ret) goto err; - ret = tc_link_training(tc, DP_TRAINING_PATTERN_2); + if (error) { + dev_err(tc->dev, "Link training phase 1 failed: %s\n", + training_pattern1_errors[error]); + ret = -ENODEV; + goto err; + } + + /* LINK TRAINING PATTERN 2 */ + + /* Set DPCD 0x102 for Training Pattern 2 */ + tc_write(DP0_SNKLTCTRL, DP_LINK_SCRAMBLING_DISABLE | DP_TRAINING_PATTERN_2); + + tc_write(DP0_SRCCTRL, tc_srcctrl(tc) | DP0_SRCCTRL_SCRMBLDIS | DP0_SRCCTRL_AUTOCORRECT | + DP0_SRCCTRL_TP2); + + /* wait */ + ret = tc_wait_link_training(tc, &error); if (ret) goto err; + if (error) { + dev_err(tc->dev, "Link training phase 2 failed: %s\n", + training_pattern2_errors[error]); + ret = -ENODEV; + goto err; + } + /* Clear Training Pattern, set AutoCorrect Mode = 1 */ tc_write(DP0_SRCCTRL, tc_srcctrl(tc) | DP0_SRCCTRL_AUTOCORRECT);