From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:47934 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754664AbeDVOBW (ORCPT ); Sun, 22 Apr 2018 10:01:22 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marc Zyngier , Heiko Stuebner Subject: [PATCH 4.16 155/196] drm/rockchip: Clear all interrupts before requesting the IRQ Date: Sun, 22 Apr 2018 15:52:55 +0200 Message-Id: <20180422135112.236961163@linuxfoundation.org> In-Reply-To: <20180422135104.278511750@linuxfoundation.org> References: <20180422135104.278511750@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Zyngier commit 5f9e93fed4d45e9a8f84728aff1a8f2ab8922902 upstream. Calling request_irq() followed by disable_irq() is usually a bad idea, specially if the interrupt can be pending, and you're not yet in a position to handle it. This is exactly what happens on my kevin system when rebooting in a second kernel using kexec: Some interrupt is left pending from the previous kernel, and we take it too early, before disable_irq() could do anything. Let's clear the pending interrupts as we initialize the HW, and move the interrupt request after that point. This ensures that we're in a sane state when the interrupt is requested. Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier [adapted to recent rockchip-drm changes] Signed-off-by: Heiko Stuebner Link: https://patchwork.freedesktop.org/patch/msgid/20180220130120.5254-2-marc.zyngier@arm.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -1414,6 +1414,9 @@ static int vop_initial(struct vop *vop) usleep_range(10, 20); reset_control_deassert(ahb_rst); + VOP_INTR_SET_TYPE(vop, clear, INTR_MASK, 1); + VOP_INTR_SET_TYPE(vop, enable, INTR_MASK, 0); + memcpy(vop->regsbak, vop->regs, vop->len); VOP_REG_SET(vop, misc, global_regdone_en, 1); @@ -1569,17 +1572,9 @@ static int vop_bind(struct device *dev, mutex_init(&vop->vsync_mutex); - ret = devm_request_irq(dev, vop->irq, vop_isr, - IRQF_SHARED, dev_name(dev), vop); - if (ret) - return ret; - - /* IRQ is initially disabled; it gets enabled in power_on */ - disable_irq(vop->irq); - ret = vop_create_crtc(vop); if (ret) - goto err_enable_irq; + return ret; pm_runtime_enable(&pdev->dev); @@ -1590,13 +1585,19 @@ static int vop_bind(struct device *dev, goto err_disable_pm_runtime; } + ret = devm_request_irq(dev, vop->irq, vop_isr, + IRQF_SHARED, dev_name(dev), vop); + if (ret) + goto err_disable_pm_runtime; + + /* IRQ is initially disabled; it gets enabled in power_on */ + disable_irq(vop->irq); + return 0; err_disable_pm_runtime: pm_runtime_disable(&pdev->dev); vop_destroy_crtc(vop); -err_enable_irq: - enable_irq(vop->irq); /* To balance out the disable_irq above */ return ret; }