Commit bda53145 authored by Sarah Sharp's avatar Sarah Sharp Committed by Greg Kroah-Hartman
Browse files

USB: xhci: Performance - move xhci_work() into xhci_irq() 



When we move xhci_work() into xhci_irq(), we don't need to read the operational
register status field twice.

Signed-off-by: default avatarSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 9032cd52

drivers/usb/host/xhci-ring.c

+30 −43
Original line number Diff line number Diff line
@@ -2030,48 +2030,6 @@ void xhci_handle_event(struct xhci_hcd *xhci) 
	/* Are there more items on the event ring? */

	xhci_handle_event(xhci);

}

/*

 * Called in interrupt context when there might be work

 * queued on the event ring

 *

 * xhci->lock must be held by caller.

 */

static void xhci_work(struct xhci_hcd *xhci)

{

	u32 temp;

	u64 temp_64;



	/*

	 * Clear the op reg interrupt status first,

	 * so we can receive interrupts from other MSI-X interrupters.

	 * Write 1 to clear the interrupt status.

	 */

	temp = xhci_readl(xhci, &xhci->op_regs->status);

	temp |= STS_EINT;

	xhci_writel(xhci, temp, &xhci->op_regs->status);

	/* FIXME when MSI-X is supported and there are multiple vectors */

	/* Clear the MSI-X event interrupt status */



	/* Acknowledge the interrupt */

	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);

	temp |= 0x3;

	xhci_writel(xhci, temp, &xhci->ir_set->irq_pending);



	if (xhci->xhc_state & XHCI_STATE_DYING)

		xhci_dbg(xhci, "xHCI dying, ignoring interrupt. "

				"Shouldn't IRQs be disabled?\n");

	else

		/* FIXME this should be a delayed service routine

		 * that clears the EHB.

		 */

		xhci_handle_event(xhci);



	/* Clear the event handler busy flag (RW1C); event ring is empty. */

	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);

	xhci_write_64(xhci, temp_64 | ERST_EHB, &xhci->ir_set->erst_dequeue);

	/* Flush posted writes -- FIXME is this necessary? */

	xhci_readl(xhci, &xhci->ir_set->irq_pending);

}



/*

 * xHCI spec says we can get an interrupt, and if the HC has an error condition,
@@ -2083,6 +2041,7 @@ irqreturn_t xhci_irq(struct usb_hcd *hcd) 
	struct xhci_hcd *xhci = hcd_to_xhci(hcd);

	u32 temp, temp2;

	union xhci_trb *trb;

	u64 temp_64;



	spin_lock(&xhci->lock);

	trb = xhci->event_ring->dequeue;
@@ -2117,7 +2076,35 @@ irqreturn_t xhci_irq(struct usb_hcd *hcd) 
		return -ESHUTDOWN;

	}



	xhci_work(xhci);

	/*

	 * Clear the op reg interrupt status first,

	 * so we can receive interrupts from other MSI-X interrupters.

	 * Write 1 to clear the interrupt status.

	 */

	temp |= STS_EINT;

	xhci_writel(xhci, temp, &xhci->op_regs->status);

	/* FIXME when MSI-X is supported and there are multiple vectors */

	/* Clear the MSI-X event interrupt status */



	/* Acknowledge the interrupt */

	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);

	temp |= 0x3;

	xhci_writel(xhci, temp, &xhci->ir_set->irq_pending);



	if (xhci->xhc_state & XHCI_STATE_DYING)

		xhci_dbg(xhci, "xHCI dying, ignoring interrupt. "

				"Shouldn't IRQs be disabled?\n");

	else

		/* FIXME this should be a delayed service routine

		 * that clears the EHB.

		 */

		xhci_handle_event(xhci);



	/* Clear the event handler busy flag (RW1C); event ring is empty. */

	temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);

	xhci_write_64(xhci, temp_64 | ERST_EHB, &xhci->ir_set->erst_dequeue);

	/* Flush posted writes -- FIXME is this necessary? */

	xhci_readl(xhci, &xhci->ir_set->irq_pending);

	spin_unlock(&xhci->lock);



	return IRQ_HANDLED;