From 52a2a1087b5924de00484f35ef5e2a73f61dbd22 Mon Sep 17 00:00:00 2001 From: Sergei Shtylyov Date: Sat, 1 Jun 2013 02:38:35 +0400 Subject: sata_rcar: fix interrupt handling 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 Cc: stable@vger.kernel.org --- drivers/ata/sata_rcar.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) (limited to 'drivers/ata') diff --git a/drivers/ata/sata_rcar.c b/drivers/ata/sata_rcar.c index a8e091aafdde..249c8a289bfd 100644 --- a/drivers/ata/sata_rcar.c +++ b/drivers/ata/sata_rcar.c @@ -619,17 +619,16 @@ static struct ata_port_operations sata_rcar_port_ops = { .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); @@ -642,7 +641,6 @@ static int sata_rcar_serr_interrupt(struct ata_port *ap) ata_ehi_push_desc(ehi, "%s", "hotplug"); freeze = serror & SERR_COMM_WAKE ? 0 : 1; - handled = 1; } /* freeze or abort */ @@ -650,11 +648,9 @@ static int sata_rcar_serr_interrupt(struct ata_port *ap) 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; @@ -663,7 +659,9 @@ static int sata_rcar_ata_interrupt(struct ata_port *ap) 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) @@ -678,20 +676,21 @@ static irqreturn_t sata_rcar_interrupt(int irq, void *dev_instance) 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); -- cgit v1.2.3