From patchwork Fri Aug 9 19:35:55 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Anderson X-Patchwork-Id: 13759212 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7EF54C52D7C for ; Fri, 9 Aug 2024 19:38:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=V/KsopdPTSQejykMzz4/KUwl6vzi9Fn3LMN3IMFqYkw=; b=0hAwSFRMXo9u1/vfrPoB8dZTNA 9lEpSox9zdeO5lbWOnfeI5JlZsH7gtEsgQy0jHHcDfPTZnzwi7LiS+thQKqZ8KgZOBbR0Dnv94m3X vaObJKf+Rfg9NJmzfaJ+A9e/Vids2+4jsBj/bUqGL1Qt0gHA2EiDSGtOTsEjFtgZo1JCCvIsdjnw0 Y44OCS2nP+eXdndKUuyaEb/VqqT5KqmZyV7F7cg5HorMXokwWBWqkhqgqiDVaOsLD+Adj0SoHBDW5 mu4meFeeGOZ3eYx6HY+YpFSGtbA/BGjshvrBXYPdaSgfh+iPFbqWs4m2/HazvllrNmqCF/TsUE0b+ hDn45tDQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1scVRj-0000000CO6k-1eDC; Fri, 09 Aug 2024 19:38:43 +0000 Received: from out-175.mta1.migadu.com ([2001:41d0:203:375::af]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1scVPX-0000000CNLh-0ZdV for linux-arm-kernel@lists.infradead.org; Fri, 09 Aug 2024 19:36:28 +0000 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1723232185; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=V/KsopdPTSQejykMzz4/KUwl6vzi9Fn3LMN3IMFqYkw=; b=B23VV0lE1r2lFe78E3CYGMuWjiMj7w6JQLu2XaJj+bujPjO8sntj4Mp14DZXB4sg//pmM4 z/2WSCar11D/Vf7/VQX49rqTRHZOMQy6TGxYaj/R8GCQMJYqklzCO6ZS4giMGESbr3w9TO xpZ5zYZDE4kuCyWncSJcjUAAfWdp1xc= From: Sean Anderson To: Laurent Pinchart , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, David Airlie , Michal Simek , Daniel Vetter , Tomi Valkeinen , Sean Anderson Subject: [PATCH v6 3/8] drm: zynqmp_dp: Don't retrain the link in our IRQ Date: Fri, 9 Aug 2024 15:35:55 -0400 Message-Id: <20240809193600.3360015-4-sean.anderson@linux.dev> In-Reply-To: <20240809193600.3360015-1-sean.anderson@linux.dev> References: <20240809193600.3360015-1-sean.anderson@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240809_123627_340153_B4CADF14 X-CRM114-Status: GOOD ( 15.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Retraining the link can take a while, and might involve waiting for DPCD reads/writes to complete. In preparation for unthreading the IRQ handler, move this into its own work function. Signed-off-by: Sean Anderson --- (no changes since v2) Changes in v2: - Document hpd_irq_work - Split this off from the locking changes drivers/gpu/drm/xlnx/zynqmp_dp.c | 45 ++++++++++++++++++++------------ 1 file changed, 29 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c b/drivers/gpu/drm/xlnx/zynqmp_dp.c index abfccd8bb5a7..cec5711c7026 100644 --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c @@ -289,6 +289,7 @@ struct zynqmp_dp_config { * @phy: PHY handles for DP lanes * @num_lanes: number of enabled phy lanes * @hpd_work: hot plug detection worker + * @hpd_irq_work: hot plug detection IRQ worker * @status: connection status * @enabled: flag to indicate if the device is enabled * @dpcd: DP configuration data from currently connected sink device @@ -304,6 +305,7 @@ struct zynqmp_dp { struct drm_dp_aux aux; struct drm_bridge bridge; struct work_struct hpd_work; + struct work_struct hpd_irq_work; struct mutex lock; struct drm_bridge *next_bridge; @@ -1671,6 +1673,29 @@ static void zynqmp_dp_hpd_work_func(struct work_struct *work) drm_bridge_hpd_notify(&dp->bridge, status); } +static void zynqmp_dp_hpd_irq_work_func(struct work_struct *work) +{ + struct zynqmp_dp *dp = container_of(work, struct zynqmp_dp, + hpd_irq_work); + u8 status[DP_LINK_STATUS_SIZE + 2]; + int err; + + mutex_lock(&dp->lock); + err = drm_dp_dpcd_read(&dp->aux, DP_SINK_COUNT, status, + DP_LINK_STATUS_SIZE + 2); + if (err < 0) { + dev_dbg_ratelimited(dp->dev, + "could not read sink status: %d\n", err); + } else { + if (status[4] & DP_LINK_STATUS_UPDATED || + !drm_dp_clock_recovery_ok(&status[2], dp->mode.lane_cnt) || + !drm_dp_channel_eq_ok(&status[2], dp->mode.lane_cnt)) { + zynqmp_dp_train_loop(dp); + } + } + mutex_unlock(&dp->lock); +} + static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data) { struct zynqmp_dp *dp = (struct zynqmp_dp *)data; @@ -1702,23 +1727,9 @@ static irqreturn_t zynqmp_dp_irq_handler(int irq, void *data) if (status & ZYNQMP_DP_INT_HPD_EVENT) schedule_work(&dp->hpd_work); - if (status & ZYNQMP_DP_INT_HPD_IRQ) { - int ret; - u8 status[DP_LINK_STATUS_SIZE + 2]; + if (status & ZYNQMP_DP_INT_HPD_IRQ) + schedule_work(&dp->hpd_irq_work); - ret = drm_dp_dpcd_read(&dp->aux, DP_SINK_COUNT, status, - DP_LINK_STATUS_SIZE + 2); - if (ret < 0) - goto handled; - - if (status[4] & DP_LINK_STATUS_UPDATED || - !drm_dp_clock_recovery_ok(&status[2], dp->mode.lane_cnt) || - !drm_dp_channel_eq_ok(&status[2], dp->mode.lane_cnt)) { - zynqmp_dp_train_loop(dp); - } - } - -handled: return IRQ_HANDLED; } @@ -1744,6 +1755,7 @@ int zynqmp_dp_probe(struct zynqmp_dpsub *dpsub) mutex_init(&dp->lock); INIT_WORK(&dp->hpd_work, zynqmp_dp_hpd_work_func); + INIT_WORK(&dp->hpd_irq_work, zynqmp_dp_hpd_irq_work_func); /* Acquire all resources (IOMEM, IRQ and PHYs). */ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dp"); @@ -1848,6 +1860,7 @@ void zynqmp_dp_remove(struct zynqmp_dpsub *dpsub) zynqmp_dp_write(dp, ZYNQMP_DP_INT_DS, ZYNQMP_DP_INT_ALL); disable_irq(dp->irq); + cancel_work_sync(&dp->hpd_irq_work); cancel_work_sync(&dp->hpd_work); zynqmp_dp_write(dp, ZYNQMP_DP_TRANSMITTER_ENABLE, 0);