Hi Tejun
On Wed, May 6, 2015 at 12:51 AM, Suman Tripathi <stripathi@xxxxxxx> wrote:
>
> This patch adds the support to handle HOST_IRQ_STAT as edge trigger
> latch.
>
> Signed-off-by: Suman Tripathi <stripathi@xxxxxxx>
> ---
> drivers/ata/ahci.h | 2 ++
> drivers/ata/libahci.c | 40 ++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 42 insertions(+)
>
> diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
> index 71262e0..f442960 100644
> --- a/drivers/ata/ahci.h
> +++ b/drivers/ata/ahci.h
> @@ -238,6 +238,8 @@ enum {
> AHCI_HFLAG_MULTI_MSI = (1 << 16), /* multiple PCI MSIs */
> AHCI_HFLAG_NO_DEVSLP = (1 << 17), /* no device sleep */
> AHCI_HFLAG_NO_FBS = (1 << 18), /* no FBS */
> + AHCI_HFLAG_EDGE_IRQ = (1 << 19), /* HOST_IRQ_STAT behaves as
> + Edge Triggered */
>
> /* ap->flags bits */
>
> diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
> index aa89c8e..1add5ba 100644
> --- a/drivers/ata/libahci.c
> +++ b/drivers/ata/libahci.c
> @@ -1853,6 +1853,43 @@ static u32 ahci_handle_port_intr(struct ata_host *host, u32 irq_masked)
> return handled;
> }
>
> +static irqreturn_t ahci_single_edge_irq_intr(int irq, void *dev_instance)
> +{
> + struct ata_host *host = dev_instance;
> + struct ahci_host_priv *hpriv;
> + unsigned int rc = 0;
> + void __iomem *mmio;
> + u32 irq_stat, irq_masked;
> +
> + VPRINTK("ENTER\n");
> +
> + hpriv = host->private_data;
> + mmio = hpriv->mmio;
> +
> + /* sigh. 0xffffffff is a valid return from h/w */
> + irq_stat = readl(mmio + HOST_IRQ_STAT);
> + if (!irq_stat)
> + return IRQ_NONE;
> +
> + irq_masked = irq_stat & hpriv->port_map;
> +
> + spin_lock(&host->lock);
> +
> + /*
> + * HOST_IRQ_STAT behaves as edge triggered latch meaning that
> + * it should be cleared before all the port events are cleared.
> + */
> + writel(irq_stat, mmio + HOST_IRQ_STAT);
> +
> + rc = ahci_handle_port_intr(host, irq_masked);
> +
> + spin_unlock(&host->lock);
> +
> + VPRINTK("EXIT\n");
> +
> + return IRQ_RETVAL(rc);
> +}
> +
> static irqreturn_t ahci_single_level_irq_intr(int irq, void *dev_instance)
> {
> struct ata_host *host = dev_instance;
> @@ -2495,6 +2532,9 @@ int ahci_host_activate(struct ata_host *host, int irq,
>
> if (hpriv->flags & AHCI_HFLAG_MULTI_MSI)
> rc = ahci_host_activate_multi_irqs(host, irq, sht);
> + else if (hpriv->flags & AHCI_HFLAG_EDGE_IRQ)
> + rc = ata_host_activate(host, irq, ahci_single_edge_irq_intr,
> + IRQF_SHARED, sht);
> else
> rc = ata_host_activate(host, irq, ahci_single_level_irq_intr,
> IRQF_SHARED, sht);
> --
> 1.8.2.1
>
Any comments on this version ??
--
Thanks,
with regards,
Suman Tripathi
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