sata_mv: cache main_irq_mask register in hpriv

Part five of simplifying/fixing handling of the main_irq_mask register
to resolve unexpected interrupt issues observed in 2.6.26-rc*.

Keep a cached copy of the main_irq_mask so that we don't have
to stall the CPU to read it on every pass through mv_interrupt.

This significantly speeds up interrupt handling, both for sata_mv,
and for any other driver/device sharing the same PCI IRQ line.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Mark Lord 2008-05-17 13:38:00 -04:00 committed by Jeff Garzik
parent a44253d24a
commit 96e2c48793

View File

@ -458,6 +458,7 @@ struct mv_port_signal {
struct mv_host_priv {
u32 hp_flags;
u32 main_irq_mask;
struct mv_port_signal signal[8];
const struct mv_hw_ops *ops;
int n_ports;
@ -843,10 +844,12 @@ static void mv_set_main_irq_mask(struct ata_host *host,
struct mv_host_priv *hpriv = host->private_data;
u32 old_mask, new_mask;
old_mask = readl(hpriv->main_irq_mask_addr);
old_mask = hpriv->main_irq_mask;
new_mask = (old_mask & ~disable_bits) | enable_bits;
if (new_mask != old_mask)
if (new_mask != old_mask) {
hpriv->main_irq_mask = new_mask;
writelfl(new_mask, hpriv->main_irq_mask_addr);
}
}
static void mv_enable_port_irqs(struct ata_port *ap,
@ -2200,12 +2203,11 @@ static irqreturn_t mv_interrupt(int irq, void *dev_instance)
struct ata_host *host = dev_instance;
struct mv_host_priv *hpriv = host->private_data;
unsigned int handled = 0;
u32 main_irq_cause, main_irq_mask, pending_irqs;
u32 main_irq_cause, pending_irqs;
spin_lock(&host->lock);
main_irq_cause = readl(hpriv->main_irq_cause_addr);
main_irq_mask = readl(hpriv->main_irq_mask_addr);
pending_irqs = main_irq_cause & main_irq_mask;
pending_irqs = main_irq_cause & hpriv->main_irq_mask;
/*
* Deal with cases where we either have nothing pending, or have read
* a bogus register value which can indicate HW removal or PCI fault.