Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932963Ab3FEVfw (ORCPT ); Wed, 5 Jun 2013 17:35:52 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:37922 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932559Ab3FEVft (ORCPT ); Wed, 5 Jun 2013 17:35:49 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sergei Shtylyov , Tejun Heo Subject: [ 075/127] sata_rcar: fix interrupt handling Date: Wed, 5 Jun 2013 14:34:02 -0700 Message-Id: <20130605213226.451713988@linuxfoundation.org> X-Mailer: git-send-email 1.8.3.rc0.20.gb99dd2e In-Reply-To: <20130605213217.966891866@linuxfoundation.org> References: <20130605213217.966891866@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3609 Lines: 115 3.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sergei Shtylyov commit 52a2a1087b5924de00484f35ef5e2a73f61dbd22 upstream. The driver's interrupt handling code is too picky in deciding whether it should handle an interrupt or not which causes completely unneeded spurious interrupts. Thus make sata_rcar_{ata|serr}_interrupt() *void*; add ATA status register read to sata_rcar_ata_interrupt() to clear an unexpected ATA interrupt -- it doesn't get cleared by writing to the SATAINTSTAT register in the interrupt mode we use. Also, in sata_rcar_ata_interrupt() we should check SATAINTSTAT register only for enabled interrupts and we should clear only those interrupts that we have read as active first time around, because else we have a race and risk clearing an interrupt that can occur between read and write of the SATAINTSTAT register and never registering it... Signed-off-by: Sergei Shtylyov Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- drivers/ata/sata_rcar.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) --- a/drivers/ata/sata_rcar.c +++ b/drivers/ata/sata_rcar.c @@ -618,17 +618,16 @@ static struct ata_port_operations sata_r .bmdma_status = sata_rcar_bmdma_status, }; -static int sata_rcar_serr_interrupt(struct ata_port *ap) +static void sata_rcar_serr_interrupt(struct ata_port *ap) { struct sata_rcar_priv *priv = ap->host->private_data; struct ata_eh_info *ehi = &ap->link.eh_info; int freeze = 0; - int handled = 0; u32 serror; serror = ioread32(priv->base + SCRSERR_REG); if (!serror) - return 0; + return; DPRINTK("SError @host_intr: 0x%x\n", serror); @@ -641,7 +640,6 @@ static int sata_rcar_serr_interrupt(stru ata_ehi_push_desc(ehi, "%s", "hotplug"); freeze = serror & SERR_COMM_WAKE ? 0 : 1; - handled = 1; } /* freeze or abort */ @@ -649,11 +647,9 @@ static int sata_rcar_serr_interrupt(stru ata_port_freeze(ap); else ata_port_abort(ap); - - return handled; } -static int sata_rcar_ata_interrupt(struct ata_port *ap) +static void sata_rcar_ata_interrupt(struct ata_port *ap) { struct ata_queued_cmd *qc; int handled = 0; @@ -662,7 +658,9 @@ static int sata_rcar_ata_interrupt(struc if (qc) handled |= ata_bmdma_port_intr(ap, qc); - return handled; + /* be sure to clear ATA interrupt */ + if (!handled) + sata_rcar_check_status(ap); } static irqreturn_t sata_rcar_interrupt(int irq, void *dev_instance) @@ -677,20 +675,21 @@ static irqreturn_t sata_rcar_interrupt(i spin_lock_irqsave(&host->lock, flags); sataintstat = ioread32(priv->base + SATAINTSTAT_REG); + sataintstat &= SATA_RCAR_INT_MASK; if (!sataintstat) goto done; /* ack */ - iowrite32(sataintstat & ~SATA_RCAR_INT_MASK, - priv->base + SATAINTSTAT_REG); + iowrite32(~sataintstat & 0x7ff, priv->base + SATAINTSTAT_REG); ap = host->ports[0]; if (sataintstat & SATAINTSTAT_ATA) - handled |= sata_rcar_ata_interrupt(ap); + sata_rcar_ata_interrupt(ap); if (sataintstat & SATAINTSTAT_SERR) - handled |= sata_rcar_serr_interrupt(ap); + sata_rcar_serr_interrupt(ap); + handled = 1; done: spin_unlock_irqrestore(&host->lock, flags); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/