Commit e390909a authored by Sanjay R Mehta's avatar Sanjay R Mehta Committed by Mika Westerberg
Browse files

thunderbolt: Add vendor specific NHI quirk for auto-clearing interrupt status 



Introduce nhi_check_quirks() routine to handle any vendor specific quirks
to manage a hardware specific implementation.

On Intel hardware the USB4 controller supports clearing the interrupt
status register automatically right after it is being issued. For this
reason add a new quirk that does that on all Intel hardware.

Signed-off-by: default avatarBasavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: default avatarSanjay R Mehta <sanju.mehta@amd.com>
Signed-off-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
parent 1651d9e7

drivers/thunderbolt/nhi.c

+25 −8
Original line number Diff line number Diff line
@@ -35,6 +35,8 @@ 


#define NHI_MAILBOX_TIMEOUT	500 /* ms */



#define QUIRK_AUTO_CLEAR_INT	BIT(0)



static int ring_interrupt_index(struct tb_ring *ring)

{

	int bit = ring->hop;
@@ -66,15 +68,18 @@ static void ring_interrupt_active(struct tb_ring *ring, bool active) 
		else

			index = ring->hop + ring->nhi->hop_count;



		if (ring->nhi->quirks & QUIRK_AUTO_CLEAR_INT) {

			/*

		 * Ask the hardware to clear interrupt status bits automatically

		 * since we already know which interrupt was triggered.

			 * Ask the hardware to clear interrupt status

			 * bits automatically since we already know

			 * which interrupt was triggered.

			 */

			misc = ioread32(ring->nhi->iobase + REG_DMA_MISC);

			if (!(misc & REG_DMA_MISC_INT_AUTO_CLEAR)) {

				misc |= REG_DMA_MISC_INT_AUTO_CLEAR;

				iowrite32(misc, ring->nhi->iobase + REG_DMA_MISC);

			}

		}



		ivr_base = ring->nhi->iobase + REG_INT_VEC_ALLOC_BASE;

		step = index / REG_INT_VEC_ALLOC_REGS * REG_INT_VEC_ALLOC_BITS;
@@ -1074,6 +1079,16 @@ static void nhi_shutdown(struct tb_nhi *nhi) 
		nhi->ops->shutdown(nhi);

}



static void nhi_check_quirks(struct tb_nhi *nhi)

{

	/*

	 * Intel hardware supports auto clear of the interrupt status

	 * reqister right after interrupt is being issued.

	 */

	if (nhi->pdev->vendor == PCI_VENDOR_ID_INTEL)

		nhi->quirks |= QUIRK_AUTO_CLEAR_INT;

}



static int nhi_init_msi(struct tb_nhi *nhi)

{

	struct pci_dev *pdev = nhi->pdev;
@@ -1190,6 +1205,8 @@ static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id) 
	if (!nhi->tx_rings || !nhi->rx_rings)

		return -ENOMEM;



	nhi_check_quirks(nhi);



	res = nhi_init_msi(nhi);

	if (res) {

		dev_err(&pdev->dev, "cannot enable MSI, aborting\n");

include/linux/thunderbolt.h

+2 −0
Original line number Diff line number Diff line
@@ -468,6 +468,7 @@ static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc) 
 * @interrupt_work: Work scheduled to handle ring interrupt when no

 *		    MSI-X is used.

 * @hop_count: Number of rings (end point hops) supported by NHI.

 * @quirks: NHI specific quirks if any

 */

struct tb_nhi {

	spinlock_t lock;
@@ -480,6 +481,7 @@ struct tb_nhi { 
	bool going_away;

	struct work_struct interrupt_work;

	u32 hop_count;

	unsigned long quirks;

};



/**