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sata_mv fix mv_host_intr bug for hc_irq_cause

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Remove the unwanted reads of hc_irq_cause from mv_host_intr(),
thereby removing a bug whereby we were not always reading it when needed..

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Mark Lord 2008-05-02 02:13:27 -04:00 committed by Jeff Garzik
parent 37b9046a3e
commit eabd5eb1cb
1 changed files with 42 additions and 29 deletions
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71
drivers/ata/sata_mv.c
View file

@ -1818,48 +1818,61 @@ static void mv_process_crpb_entries(struct ata_port *ap, struct mv_port_priv *pp
static int mv_host_intr(struct ata_host *host, u32 main_irq_cause)
{
struct mv_host_priv *hpriv = host->private_data;
void __iomem *mmio = hpriv->base, *hc_mmio = NULL;
u32 hc_irq_cause = 0;
void __iomem *mmio = hpriv->base, *hc_mmio;
unsigned int handled = 0, port;
for (port = 0; port < hpriv->n_ports; port++) {
struct ata_port *ap = host->ports[port];
struct mv_port_priv *pp;
unsigned int shift, hardport, port_cause;
/*
* When we move to the second hc, flag our cached
* copies of hc_mmio (and hc_irq_cause) as invalid again.
*/
if (port == MV_PORTS_PER_HC)
hc_mmio = NULL;
/*
* Do nothing if port is not interrupting or is disabled:
*/
unsigned int p, shift, hardport, port_cause;
MV_PORT_TO_SHIFT_AND_HARDPORT(port, shift, hardport);
port_cause = (main_irq_cause >> shift) & (DONE_IRQ | ERR_IRQ);
if (!port_cause || !ap || (ap->flags & ATA_FLAG_DISABLED))
continue;
/*
* Each hc within the host has its own hc_irq_cause register.
* We defer reading it until we know we need it, right now:
*
* FIXME later: we don't really need to read this register
* (some logic changes required below if we go that way),
* because it doesn't tell us anything new. But we do need
* to write to it, outside the top of this loop,
* to reset the interrupt triggers for next time.
* Each hc within the host has its own hc_irq_cause register,
* where the interrupting ports bits get ack'd.
*/
if (!hc_mmio) {
if (hardport == 0) { /* first port on this hc ? */
u32 hc_cause = (main_irq_cause >> shift) & HC0_IRQ_PEND;
u32 port_mask, ack_irqs;
/*
* Skip this entire hc if nothing pending for any ports
*/
if (!hc_cause) {
port += MV_PORTS_PER_HC - 1;
continue;
}
/*
* We don't need/want to read the hc_irq_cause register,
* because doing so hurts performance, and
* main_irq_cause already gives us everything we need.
*
* But we do have to *write* to the hc_irq_cause to ack
* the ports that we are handling this time through.
*
* This requires that we create a bitmap for those
* ports which interrupted us, and use that bitmap
* to ack (only) those ports via hc_irq_cause.
*/
ack_irqs = 0;
for (p = 0; p < MV_PORTS_PER_HC; ++p) {
if ((port + p) >= hpriv->n_ports)
break;
port_mask = (DONE_IRQ | ERR_IRQ) << (p * 2);
if (hc_cause & port_mask)
ack_irqs |= (DMA_IRQ | DEV_IRQ) << p;
}
hc_mmio = mv_hc_base_from_port(mmio, port);
hc_irq_cause = readl(hc_mmio + HC_IRQ_CAUSE_OFS);
writelfl(~hc_irq_cause, hc_mmio + HC_IRQ_CAUSE_OFS);
writelfl(~ack_irqs, hc_mmio + HC_IRQ_CAUSE_OFS);
handled = 1;
}
port_cause = (main_irq_cause >> shift) & (DONE_IRQ | ERR_IRQ);
if (!port_cause)
continue;
/*
* Process completed CRPB response(s) before other events.
*/
pp = ap->private_data;
if (hc_irq_cause & (DMA_IRQ << hardport)) {
if (port_cause & DONE_IRQ) {
if (pp->pp_flags & MV_PP_FLAG_EDMA_EN)
mv_process_crpb_entries(ap, pp);
}
@ -1868,15 +1881,15 @@ static int mv_host_intr(struct ata_host *host, u32 main_irq_cause)
*/
if (unlikely(port_cause & ERR_IRQ)) {
mv_err_intr(ap);
} else if (hc_irq_cause & (DEV_IRQ << hardport)) {
} else {
if (!(pp->pp_flags & MV_PP_FLAG_EDMA_EN)) {
struct ata_queued_cmd *qc = mv_get_active_qc(ap);
if (qc) {
ata_sff_host_intr(ap, qc);
continue;
}
mv_unexpected_intr(ap);
}
mv_unexpected_intr(ap);
}
}
return handled;