From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754536AbaELJVA (ORCPT ); Mon, 12 May 2014 05:21:00 -0400 Received: from mga09.intel.com ([134.134.136.24]:57347 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751115AbaELJUx (ORCPT ); Mon, 12 May 2014 05:20:53 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,1033,1389772800"; d="scan'208";a="510161848" From: Tomas Winkler To: gregkh@linuxfoundation.org Cc: arnd@arndb.de, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Tomas Winkler , Alexander Usyskin Subject: [char-misc 1/3] mei: me: fix hw ready reset flow Date: Mon, 12 May 2014 12:19:39 +0300 Message-Id: <1399886381-16040-2-git-send-email-tomas.winkler@intel.com> X-Mailer: git-send-email 1.9.0 In-Reply-To: <1399886381-16040-1-git-send-email-tomas.winkler@intel.com> References: <1399886381-16040-1-git-send-email-tomas.winkler@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We cleared H_RST for H_CSR on spurious interrupt generated when ME_RDY while cleared and not while ME_RDY is set. The spurious interrupt is not delivered on all platforms in this case the driver may fail to initialize. Cc: stable@vger.kernel.org Signed-off-by: Tomas Winkler Signed-off-by: Alexander Usyskin --- drivers/misc/mei/hw-me.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c index a31bc4c..ac76a63 100644 --- a/drivers/misc/mei/hw-me.c +++ b/drivers/misc/mei/hw-me.c @@ -181,6 +181,9 @@ static void mei_me_hw_reset_release(struct mei_device *dev) hcsr |= H_IG; hcsr &= ~H_RST; mei_hcsr_set(hw, hcsr); + + /* complete this write before we set host ready on another CPU */ + mmiowb(); } /** * mei_me_hw_reset - resets fw via mei csr register. @@ -218,6 +221,7 @@ static int mei_me_hw_reset(struct mei_device *dev, bool intr_enable) static void mei_me_host_set_ready(struct mei_device *dev) { struct mei_me_hw *hw = to_me_hw(dev); + hw->host_hw_state = mei_hcsr_read(hw); hw->host_hw_state |= H_IE | H_IG | H_RDY; mei_hcsr_set(hw, hw->host_hw_state); } @@ -646,14 +650,13 @@ irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id) /* check if we need to start the dev */ if (!mei_host_is_ready(dev)) { if (mei_hw_is_ready(dev)) { + mei_me_hw_reset_release(dev); dev_dbg(&dev->pdev->dev, "we need to start the dev.\n"); dev->recvd_hw_ready = true; wake_up_interruptible(&dev->wait_hw_ready); } else { - - dev_dbg(&dev->pdev->dev, "Reset Completed.\n"); - mei_me_hw_reset_release(dev); + dev_dbg(&dev->pdev->dev, "Spurious Interrupt\n"); } goto end; } -- 1.9.0