From e390909ac763589558ffb91856f121820f933e4b Mon Sep 17 00:00:00 2001 From: Sanjay R Mehta Date: Fri, 6 Aug 2021 11:59:05 -0500 Subject: 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: Basavaraj Natikar Signed-off-by: Sanjay R Mehta Signed-off-by: Mika Westerberg --- drivers/thunderbolt/nhi.c | 33 +++++++++++++++++++++++++-------- 1 file changed, 25 insertions(+), 8 deletions(-) (limited to 'drivers/thunderbolt/nhi.c') diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c index fa44332845a1..c7a2841ed3b7 100644 --- a/drivers/thunderbolt/nhi.c +++ b/drivers/thunderbolt/nhi.c @@ -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; @@ -66,14 +68,17 @@ static void ring_interrupt_active(struct tb_ring *ring, bool active) else index = ring->hop + ring->nhi->hop_count; - /* - * 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); + 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. + */ + 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; @@ -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"); -- cgit v1.2.3