On Mon, May 4, 2015 at 9:17 PM, Tejun Heo <tj@xxxxxxxxxx> wrote: > On Sun, May 03, 2015 at 09:03:39PM +0530, Suman Tripathi wrote: >> This patch adds the support to handle HOST_IRQ_STAT as edge trigger >> latch. > ... >> + /* >> + * HOST_IRQ_STAT behaves as edge trigger latch. When HOST_IRQ_STAT >> + * detects a egde from PORT_IRQ_STAT, it happens to loose interrupts >> + * when interrupts are triggered from both ports. So handling of >> + * the residual interrupt is required. >> + */ >> + if (hpriv->flags & AHCI_HFLAG_EDGE_TRIG_IRQ) { >> + for (i = 0; i < host->n_ports; i++) { >> + struct ata_port *ap; >> + >> + ap = host->ports[i]; >> + if (ap) { >> + ahci_port_intr(ap); >> + VPRINTK("Residual irq from port %u\n", i); >> + } >> + handled = 1; >> + } >> + } > > This is kinda gross. The right thing do is clearing irq stat > registers before handling the events, right? That shouldn't be too > difficult to implement. Create a separate set of irq functions which > clear irqs before processing rather than after. AFAIK clearing host_irq_stat means we have handled port interrupts . Now for our case we still have interrupts left because it didn't get detected on first ahci_port_intr. So you mean to handle that residual irq in the next cycle (i mean next call intr handler ) ?? > > Thanks. > > -- > tejun -- Thanks, with regards, Suman Tripathi -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html