Enable reliable use of Message Switched Interrupts (MSI) in sata_mv by masking further chip interrupts within the main interrupt handler. Based upon a suggestion by Grant Grundler. Signed-off-by: Mark Lord <mlord@xxxxxxxxx> --- old/drivers/ata/sata_mv.c 2009-01-19 17:18:31.000000000 -0500 +++ linux/drivers/ata/sata_mv.c 2009-01-19 17:12:51.000000000 -0500 @@ -33,8 +33,6 @@ * * --> ATAPI support (Marvell claims the 60xx/70xx chips can do it). * - * --> Investigate problems with PCI Message Signalled Interrupts (MSI). - * * --> Develop a low-power-consumption strategy, and implement it. * * --> [Experiment, low priority] Investigate interrupt coalescing. @@ -2199,9 +2197,15 @@ struct ata_host *host = dev_instance; struct mv_host_priv *hpriv = host->private_data; unsigned int handled = 0; + int using_msi = hpriv->hp_flags & MV_HP_FLAG_MSI; u32 main_irq_cause, pending_irqs; spin_lock(&host->lock); + + /* for MSI: block new interrupts while in here */ + if (using_msi) + writel(0, hpriv->main_irq_mask_addr); + main_irq_cause = readl(hpriv->main_irq_cause_addr); pending_irqs = main_irq_cause & hpriv->main_irq_mask; /* @@ -2215,6 +2219,11 @@ handled = mv_host_intr(host, pending_irqs); } spin_unlock(&host->lock); + + /* for MSI: unblock interupts; anything pending will hit us now */ + if (using_msi) + writel(hpriv->main_irq_mask, hpriv->main_irq_mask_addr); + return IRQ_RETVAL(handled); } -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
