From patchwork Tue Jun 6 15:17:21 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liviu Dudau X-Patchwork-Id: 9769131 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 2BC216034B for ; Tue, 6 Jun 2017 15:17:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1CECD2849E for ; Tue, 6 Jun 2017 15:17:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 11C11284A8; Tue, 6 Jun 2017 15:17:26 +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=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 94B642849E for ; Tue, 6 Jun 2017 15:17:25 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DB8F76E133; Tue, 6 Jun 2017 15:17:24 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from cam-smtp0.cambridge.arm.com (fw-tnat.cambridge.arm.com [217.140.96.140]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2A5BE6E133 for ; Tue, 6 Jun 2017 15:17:23 +0000 (UTC) Received: from e110455-lin.cambridge.arm.com (e110455-lin.cambridge.arm.com [10.2.131.9]) by cam-smtp0.cambridge.arm.com (8.13.8/8.13.8) with ESMTP id v56FHL0A019913; Tue, 6 Jun 2017 16:17:21 +0100 From: Liviu Dudau To: dri-devel@lists.freedesktop.org Subject: [PATCH] drm/mali-dp: Check PM status when sharing interrupt lines Date: Tue, 6 Jun 2017 16:17:21 +0100 Message-Id: <20170606151721.31915-1-Liviu.Dudau@arm.com> X-Mailer: git-send-email 2.13.0 Cc: Mali DP Maintainers , linux-kernel@vger.kernel.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP If an instance of Mali DP hardware shares the interrupt line with another hardware (usually another instance of the Mali DP) its interrupt handler can get called when the device is suspended. Check the PM status before making access to the hardware registers to avoid deadlocks. Signed-off-by: Liviu Dudau --- drivers/gpu/drm/arm/malidp_hw.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/arm/malidp_hw.c b/drivers/gpu/drm/arm/malidp_hw.c index 28360b8542f7..17bca99e8ac8 100644 --- a/drivers/gpu/drm/arm/malidp_hw.c +++ b/drivers/gpu/drm/arm/malidp_hw.c @@ -766,12 +766,17 @@ static irqreturn_t malidp_de_irq(int irq, void *arg) u32 status, mask, dc_status; irqreturn_t ret = IRQ_NONE; - if (!drm->dev_private) - return IRQ_HANDLED; - hwdev = malidp->dev; de = &hwdev->map.de_irq_map; + /* + * if we are suspended it is likely that we were invoked because + * we share an interrupt line with some other driver, don't try + * to read the hardware registers + */ + if (hwdev->pm_suspended) + return IRQ_NONE; + /* first handle the config valid IRQ */ dc_status = malidp_hw_read(hwdev, hwdev->map.dc_base + MALIDP_REG_STATUS); if (dc_status & hwdev->map.dc_irq_map.vsync_irq) { @@ -854,6 +859,14 @@ static irqreturn_t malidp_se_irq(int irq, void *arg) struct malidp_hw_device *hwdev = malidp->dev; u32 status, mask; + /* + * if we are suspended it is likely that we were invoked because + * we share an interrupt line with some other driver, don't try + * to read the hardware registers + */ + if (hwdev->pm_suspended) + return IRQ_NONE; + status = malidp_hw_read(hwdev, hwdev->map.se_base + MALIDP_REG_STATUS); if (!(status & hwdev->map.se_irq_map.irq_mask)) return IRQ_NONE;