From patchwork Tue Jul 15 21:28:53 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 370496 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id A3068140085; Wed, 16 Jul 2014 07:55:06 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1X7Agi-00032N-3W; Tue, 15 Jul 2014 21:55:04 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1X7ARR-00030B-Qd for kernel-team@lists.ubuntu.com; Tue, 15 Jul 2014 21:39:17 +0000 Received: from c-67-160-228-185.hsd1.ca.comcast.net ([67.160.228.185] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1X7AJo-0007Bq-Gy; Tue, 15 Jul 2014 21:31:24 +0000 Received: from kamal by fourier with local (Exim 4.82) (envelope-from ) id 1X7AJm-00044J-KL; Tue, 15 Jul 2014 14:31:22 -0700 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.13 063/198] mei: me: fix hw ready reset flow Date: Tue, 15 Jul 2014 14:28:53 -0700 Message-Id: <1405459868-15089-64-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1405459868-15089-1-git-send-email-kamal@canonical.com> References: <1405459868-15089-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Cc: Greg Kroah-Hartman , Tomas Winkler , Alexander Usyskin , Kamal Mostafa X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.13.11.5 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Tomas Winkler commit b04ada92ffaabb868497a1fce8e4f6bf74e5488f upstream. 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. Signed-off-by: Tomas Winkler Signed-off-by: Alexander Usyskin Signed-off-by: Greg Kroah-Hartman [ kamal: backport to 3.13-stable: context ] Signed-off-by: Kamal Mostafa --- drivers/misc/mei/hw-me.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c index 3412adc..f285dc1 100644 --- a/drivers/misc/mei/hw-me.c +++ b/drivers/misc/mei/hw-me.c @@ -164,6 +164,9 @@ 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. @@ -201,6 +204,7 @@ 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); } @@ -496,6 +500,7 @@ 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; @@ -504,8 +509,7 @@ irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id) mutex_unlock(&dev->device_lock); return IRQ_HANDLED; } else { - dev_dbg(&dev->pdev->dev, "Reset Completed.\n"); - mei_me_hw_reset_release(dev); + dev_dbg(&dev->pdev->dev, "Spurious Interrupt\n"); mutex_unlock(&dev->device_lock); return IRQ_HANDLED; }