From eabd5eb1cb59bfb162e7aa23007248f2bb480816 Mon Sep 17 00:00:00 2001 From: Mark Lord Date: Fri, 2 May 2008 02:13:27 -0400 Subject: sata_mv fix mv_host_intr bug for hc_irq_cause 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 Signed-off-by: Jeff Garzik --- drivers/ata/sata_mv.c | 71 ++++++++++++++++++++++++++++++--------------------- 1 file changed, 42 insertions(+), 29 deletions(-) (limited to 'drivers/ata') diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c index d995e0e15d8..31e42deb746 100644 --- a/drivers/ata/sata_mv.c +++ b/drivers/ata/sata_mv.c @@ -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; -- cgit v1.2.3