Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 43b86af8 authored by Dong Nguyen's avatar Dong Nguyen Committed by Greg Kroah-Hartman
Browse files

USB: xHCI: Supporting MSI/MSI-X 



Enable MSI/MSI-X supporting in xhci driver.

Provide the mechanism to fall back using MSI and Legacy IRQs
if MSI-X IRQs register failed.

Signed-off-by: default avatarDong Nguyen <Dong.Nguyen@amd.com>
Signed-off-by: default avatarSarah Sharp <sarah.a.sharp@linux.intel.com&gt;,>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 13dd0c97

drivers/usb/core/hcd.c

+1 −0
Original line number Diff line number Diff line
@@ -2085,6 +2085,7 @@ irqreturn_t usb_hcd_irq (int irq, void *__hcd) 
	local_irq_restore(flags);

	return rc;

}

EXPORT_SYMBOL_GPL(usb_hcd_irq);



/*-------------------------------------------------------------------------*/

drivers/usb/host/xhci.c

+126 −40
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 */



#include <linux/pci.h>

#include <linux/irq.h>

#include <linux/log2.h>

#include <linux/module.h>
@@ -171,22 +172,95 @@ int xhci_reset(struct xhci_hcd *xhci) 
	return handshake(xhci, &xhci->op_regs->status, STS_CNR, 0, 250 * 1000);

}



static irqreturn_t xhci_msi_irq(int irq, struct usb_hcd *hcd)

{

	irqreturn_t ret;



#if 0

/* Set up MSI-X table for entry 0 (may claim other entries later) */

static int xhci_setup_msix(struct xhci_hcd *xhci)

	set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);



	ret = xhci_irq(hcd);



	return ret;

}



/*

 * Free IRQs

 * free all IRQs request

 */

static void xhci_free_irq(struct xhci_hcd *xhci)

{

	int i;

	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);



	/* return if using legacy interrupt */

	if (xhci_to_hcd(xhci)->irq >= 0)

		return;



	if (xhci->msix_entries) {

		for (i = 0; i < xhci->msix_count; i++)

			if (xhci->msix_entries[i].vector)

				free_irq(xhci->msix_entries[i].vector,

						xhci_to_hcd(xhci));

	} else if (pdev->irq >= 0)

		free_irq(pdev->irq, xhci_to_hcd(xhci));



	return;

}



/*

 * Set up MSI

 */

static int xhci_setup_msi(struct xhci_hcd *xhci)

{

	int ret;

	struct pci_dev  *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);



	xhci->msix_count = 0;

	/* XXX: did I do this right?  ixgbe does kcalloc for more than one */

	xhci->msix_entries = kmalloc(sizeof(struct msix_entry), GFP_KERNEL);

	ret = pci_enable_msi(pdev);

	if (ret) {

		xhci_err(xhci, "failed to allocate MSI entry\n");

		return ret;

	}



	ret = request_irq(pdev->irq, (irq_handler_t)xhci_msi_irq,

				0, "xhci_hcd", xhci_to_hcd(xhci));

	if (ret) {

		xhci_err(xhci, "disable MSI interrupt\n");

		pci_disable_msi(pdev);

	}



	return ret;

}



/*

 * Set up MSI-X

 */

static int xhci_setup_msix(struct xhci_hcd *xhci)

{

	int i, ret = 0;

	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);



	/*

	 * calculate number of msi-x vectors supported.

	 * - HCS_MAX_INTRS: the max number of interrupts the host can handle,

	 *   with max number of interrupters based on the xhci HCSPARAMS1.

	 * - num_online_cpus: maximum msi-x vectors per CPUs core.

	 *   Add additional 1 vector to ensure always available interrupt.

	 */

	xhci->msix_count = min(num_online_cpus() + 1,

				HCS_MAX_INTRS(xhci->hcs_params1));



	xhci->msix_entries =

		kmalloc((sizeof(struct msix_entry))*xhci->msix_count,

				GFP_KERNEL);

	if (!xhci->msix_entries) {

		xhci_err(xhci, "Failed to allocate MSI-X entries\n");

		return -ENOMEM;

	}

	xhci->msix_entries[0].entry = 0;



	for (i = 0; i < xhci->msix_count; i++) {

		xhci->msix_entries[i].entry = i;

		xhci->msix_entries[i].vector = 0;

	}



	ret = pci_enable_msix(pdev, xhci->msix_entries, xhci->msix_count);

	if (ret) {
@@ -194,20 +268,19 @@ static int xhci_setup_msix(struct xhci_hcd *xhci) 
		goto free_entries;

	}



	/*

	 * Pass the xhci pointer value as the request_irq "cookie".

	 * If more irqs are added, this will need to be unique for each one.

	 */

	ret = request_irq(xhci->msix_entries[0].vector, &xhci_irq, 0,

			"xHCI", xhci_to_hcd(xhci));

	if (ret) {

		xhci_err(xhci, "Failed to allocate MSI-X interrupt\n");

	for (i = 0; i < xhci->msix_count; i++) {

		ret = request_irq(xhci->msix_entries[i].vector,

				(irq_handler_t)xhci_msi_irq,

				0, "xhci_hcd", xhci_to_hcd(xhci));

		if (ret)

			goto disable_msix;

	}

	xhci_dbg(xhci, "Finished setting up MSI-X\n");

	return 0;



	return ret;



disable_msix:

	xhci_err(xhci, "disable MSI-X interrupt\n");

	xhci_free_irq(xhci);

	pci_disable_msix(pdev);

free_entries:

	kfree(xhci->msix_entries);
@@ -215,21 +288,23 @@ free_entries: 
	return ret;

}



/* XXX: code duplication; can xhci_setup_msix call this? */

/* Free any IRQs and disable MSI-X */

static void xhci_cleanup_msix(struct xhci_hcd *xhci)

{

	struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);

	if (!xhci->msix_entries)

		return;



	free_irq(xhci->msix_entries[0].vector, xhci);

	xhci_free_irq(xhci);



	if (xhci->msix_entries) {

		pci_disable_msix(pdev);

		kfree(xhci->msix_entries);

		xhci->msix_entries = NULL;

	xhci_dbg(xhci, "Finished cleaning up MSI-X\n");

	} else {

		pci_disable_msi(pdev);

	}



	return;

}

#endif



/*

 * Initialize memory for HCD and xHC (one-time init).
@@ -423,20 +498,36 @@ int xhci_run(struct usb_hcd *hcd) 
{

	u32 temp;

	u64 temp_64;

	u32 ret;

	struct xhci_hcd *xhci = hcd_to_xhci(hcd);

	struct pci_dev  *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);

	void (*doorbell)(struct xhci_hcd *) = NULL;



	hcd->uses_new_polling = 1;



	xhci_dbg(xhci, "xhci_run\n");

#if 0	/* FIXME: MSI not setup yet */

	/* Do this at the very last minute */

	/* unregister the legacy interrupt */

	if (hcd->irq)

		free_irq(hcd->irq, hcd);

	hcd->irq = -1;



	ret = xhci_setup_msix(xhci);

	if (!ret)

	if (ret)

		/* fall back to msi*/

		ret = xhci_setup_msi(xhci);



	if (ret) {

		/* fall back to legacy interrupt*/

		ret = request_irq(pdev->irq, &usb_hcd_irq, IRQF_SHARED,

					hcd->irq_descr, hcd);

		if (ret) {

			xhci_err(xhci, "request interrupt %d failed\n",

					pdev->irq);

			return ret;

		}

		hcd->irq = pdev->irq;

	}



	return -ENOSYS;

#endif

#ifdef CONFIG_USB_XHCI_HCD_DEBUGGING

	init_timer(&xhci->event_ring_timer);

	xhci->event_ring_timer.data = (unsigned long) xhci;
@@ -520,11 +611,9 @@ void xhci_stop(struct usb_hcd *hcd) 
	spin_lock_irq(&xhci->lock);

	xhci_halt(xhci);

	xhci_reset(xhci);

	xhci_cleanup_msix(xhci);

	spin_unlock_irq(&xhci->lock);



#if 0	/* No MSI yet */

	xhci_cleanup_msix(xhci);

#endif

#ifdef CONFIG_USB_XHCI_HCD_DEBUGGING

	/* Tell the event ring poll function not to reschedule */

	xhci->zombie = 1;
@@ -558,11 +647,8 @@ void xhci_shutdown(struct usb_hcd *hcd) 


	spin_lock_irq(&xhci->lock);

	xhci_halt(xhci);

	spin_unlock_irq(&xhci->lock);



#if 0

	xhci_cleanup_msix(xhci);

#endif

	spin_unlock_irq(&xhci->lock);



	xhci_dbg(xhci, "xhci_shutdown completed - status = %x\n",

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

drivers/usb/host/xhci.h

+1 −1
Original line number Diff line number Diff line
@@ -1130,7 +1130,7 @@ struct xhci_hcd { 
	int		page_size;

	/* Valid values are 12 to 20, inclusive */

	int		page_shift;

	/* only one MSI vector for now, but might need more later */

	/* msi-x vectors */

	int		msix_count;

	struct msix_entry	*msix_entries;

	/* data structures */