From 904c7bad994e6e7f9997174e0b33fcc521862136 Mon Sep 17 00:00:00 2001 From: Mark Lord Date: Wed, 7 Nov 2007 10:53:41 -0500 Subject: [PATCH] libata sata_qstor workaround for spurious interrupts sata_qstor workaround for spurious interrupts. The qstor hardware generates spurious interrupts from time to time when switching in and out of packet mode. These eventually result in the IRQ being disabled, which kills other devices sharing this IRQ with us. This workaround isn't perfect, but it's about the best we can do for this hardware. Spurious interrupts will still happen, but won't be logged as such, and therefore won't cause the IRQ to be inadvertently disabled. Signed-off-by: Mark Lord Signed-off-by: Jeff Garzik --- drivers/ata/sata_qstor.c | 38 +++++++++++++++++++++----------------- 1 file changed, 21 insertions(+), 17 deletions(-) diff --git a/drivers/ata/sata_qstor.c b/drivers/ata/sata_qstor.c index 9d3128ca34..7446a335fc 100644 --- a/drivers/ata/sata_qstor.c +++ b/drivers/ata/sata_qstor.c @@ -425,24 +425,27 @@ static inline unsigned int qs_intr_mmio(struct ata_host *host) if (ap && !(ap->flags & ATA_FLAG_DISABLED)) { struct ata_queued_cmd *qc; - struct qs_port_priv *pp = ap->private_data; - if (!pp || pp->state != qs_state_mmio) - continue; + struct qs_port_priv *pp; qc = ata_qc_from_tag(ap, ap->link.active_tag); - if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING))) { - - /* check main status, clearing INTRQ */ - u8 status = ata_check_status(ap); - if ((status & ATA_BUSY)) - continue; - DPRINTK("ata%u: protocol %d (dev_stat 0x%X)\n", - ap->print_id, qc->tf.protocol, status); - - /* complete taskfile transaction */ - qc->err_mask |= ac_err_mask(status); - ata_qc_complete(qc); + if (!qc || !(qc->flags & ATA_QCFLAG_ACTIVE)) { + /* + * The qstor hardware generates spurious + * interrupts from time to time when switching + * in and out of packet mode. + * There's no obvious way to know if we're + * here now due to that, so just ack the irq + * and pretend we knew it was ours.. (ugh). + * This does not affect packet mode. + */ + ata_check_status(ap); handled = 1; + continue; } + pp = ap->private_data; + if (!pp || pp->state != qs_state_mmio) + continue; + if (!(qc->tf.flags & ATA_TFLAG_POLLING)) + handled |= ata_host_intr(ap, qc); } } return handled; @@ -452,12 +455,13 @@ static irqreturn_t qs_intr(int irq, void *dev_instance) { struct ata_host *host = dev_instance; unsigned int handled = 0; + unsigned long flags; VPRINTK("ENTER\n"); - spin_lock(&host->lock); + spin_lock_irqsave(&host->lock, flags); handled = qs_intr_pkt(host) | qs_intr_mmio(host); - spin_unlock(&host->lock); + spin_unlock_irqrestore(&host->lock, flags); VPRINTK("EXIT\n"); -- 2.39.5