diff options
Diffstat (limited to 'drivers/thunderbolt/nhi.c')
| -rw-r--r-- | drivers/thunderbolt/nhi.c | 165 |
1 files changed, 143 insertions, 22 deletions
diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c index a8c20413dbda..ed75c49748f5 100644 --- a/drivers/thunderbolt/nhi.c +++ b/drivers/thunderbolt/nhi.c @@ -21,6 +21,12 @@ #define RING_TYPE(ring) ((ring)->is_tx ? "TX ring" : "RX ring") +/* + * Minimal number of vectors when we use MSI-X. Two for control channel + * Rx/Tx and the rest four are for cross domain DMA paths. + */ +#define MSIX_MIN_VECS 6 +#define MSIX_MAX_VECS 16 static int ring_interrupt_index(struct tb_ring *ring) { @@ -42,6 +48,37 @@ static void ring_interrupt_active(struct tb_ring *ring, bool active) int bit = ring_interrupt_index(ring) & 31; int mask = 1 << bit; u32 old, new; + + if (ring->irq > 0) { + u32 step, shift, ivr, misc; + void __iomem *ivr_base; + int index; + + if (ring->is_tx) + index = ring->hop; + 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); + } + + ivr_base = ring->nhi->iobase + REG_INT_VEC_ALLOC_BASE; + step = index / REG_INT_VEC_ALLOC_REGS * REG_INT_VEC_ALLOC_BITS; + shift = index % REG_INT_VEC_ALLOC_REGS * REG_INT_VEC_ALLOC_BITS; + ivr = ioread32(ivr_base + step); + ivr &= ~(REG_INT_VEC_ALLOC_MASK << shift); + if (active) + ivr |= ring->vector << shift; + iowrite32(ivr, ivr_base + step); + } + old = ioread32(ring->nhi->iobase + reg); if (active) new = old | mask; @@ -239,8 +276,50 @@ int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame) return ret; } +static irqreturn_t ring_msix(int irq, void *data) +{ + struct tb_ring *ring = data; + + schedule_work(&ring->work); + return IRQ_HANDLED; +} + +static int ring_request_msix(struct tb_ring *ring, bool no_suspend) +{ + struct tb_nhi *nhi = ring->nhi; + unsigned long irqflags; + int ret; + + if (!nhi->pdev->msix_enabled) + return 0; + + ret = ida_simple_get(&nhi->msix_ida, 0, MSIX_MAX_VECS, GFP_KERNEL); + if (ret < 0) + return ret; + + ring->vector = ret; + + ring->irq = pci_irq_vector(ring->nhi->pdev, ring->vector); + if (ring->irq < 0) + return ring->irq; + + irqflags = no_suspend ? IRQF_NO_SUSPEND : 0; + return request_irq(ring->irq, ring_msix, irqflags, "thunderbolt", ring); +} + +static void ring_release_msix(struct tb_ring *ring) +{ + if (ring->irq <= 0) + return; + + free_irq(ring->irq, ring); + ida_simple_remove(&ring->nhi->msix_ida, ring->vector); + ring->vector = 0; + ring->irq = 0; +} + static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size, - bool transmit) + bool transmit, unsigned int flags) { struct tb_ring *ring = NULL; dev_info(&nhi->pdev->dev, "allocating %s ring %d of size %d\n", @@ -271,9 +350,14 @@ static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size, ring->hop = hop; ring->is_tx = transmit; ring->size = size; + ring->flags = flags; ring->head = 0; ring->tail = 0; ring->running = false; + + if (ring_request_msix(ring, flags & RING_FLAG_NO_SUSPEND)) + goto err; + ring->descriptors = dma_alloc_coherent(&ring->nhi->pdev->dev, size * sizeof(*ring->descriptors), &ring->descriptors_dma, GFP_KERNEL | __GFP_ZERO); @@ -295,14 +379,16 @@ err: return NULL; } -struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size) +struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size, + unsigned int flags) { - return ring_alloc(nhi, hop, size, true); + return ring_alloc(nhi, hop, size, true, flags); } -struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size) +struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size, + unsigned int flags) { - return ring_alloc(nhi, hop, size, false); + return ring_alloc(nhi, hop, size, false, flags); } /** @@ -413,6 +499,8 @@ void ring_free(struct tb_ring *ring) RING_TYPE(ring), ring->hop); } + ring_release_msix(ring); + dma_free_coherent(&ring->nhi->pdev->dev, ring->size * sizeof(*ring->descriptors), ring->descriptors, ring->descriptors_dma); @@ -428,9 +516,9 @@ void ring_free(struct tb_ring *ring) mutex_unlock(&ring->nhi->lock); /** - * ring->work can no longer be scheduled (it is scheduled only by - * nhi_interrupt_work and ring_stop). Wait for it to finish before - * freeing the ring. + * ring->work can no longer be scheduled (it is scheduled only + * by nhi_interrupt_work, ring_stop and ring_msix). Wait for it + * to finish before freeing the ring. */ flush_work(&ring->work); mutex_destroy(&ring->lock); @@ -528,9 +616,52 @@ static void nhi_shutdown(struct tb_nhi *nhi) * We have to release the irq before calling flush_work. Otherwise an * already executing IRQ handler could call schedule_work again. */ - devm_free_irq(&nhi->pdev->dev, nhi->pdev->irq, nhi); - flush_work(&nhi->interrupt_work); + if (!nhi->pdev->msix_enabled) { + devm_free_irq(&nhi->pdev->dev, nhi->pdev->irq, nhi); + flush_work(&nhi->interrupt_work); + } mutex_destroy(&nhi->lock); + ida_destroy(&nhi->msix_ida); +} + +static int nhi_init_msi(struct tb_nhi *nhi) +{ + struct pci_dev *pdev = nhi->pdev; + int res, irq, nvec; + + /* In case someone left them on. */ + nhi_disable_interrupts(nhi); + + ida_init(&nhi->msix_ida); + + /* + * The NHI has 16 MSI-X vectors or a single MSI. We first try to + * get all MSI-X vectors and if we succeed, each ring will have + * one MSI-X. If for some reason that does not work out, we + * fallback to a single MSI. + */ + nvec = pci_alloc_irq_vectors(pdev, MSIX_MIN_VECS, MSIX_MAX_VECS, + PCI_IRQ_MSIX); + if (nvec < 0) { + nvec = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI); + if (nvec < 0) + return nvec; + + INIT_WORK(&nhi->interrupt_work, nhi_interrupt_work); + + irq = pci_irq_vector(nhi->pdev, 0); + if (irq < 0) + return irq; + + res = devm_request_irq(&pdev->dev, irq, nhi_msi, + IRQF_NO_SUSPEND, "thunderbolt", nhi); + if (res) { + dev_err(&pdev->dev, "request_irq failed, aborting\n"); + return res; + } + } + + return 0; } static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id) @@ -545,12 +676,6 @@ static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id) return res; } - res = pci_enable_msi(pdev); - if (res) { - dev_err(&pdev->dev, "cannot enable MSI, aborting\n"); - return res; - } - res = pcim_iomap_regions(pdev, 1 << 0, "thunderbolt"); if (res) { dev_err(&pdev->dev, "cannot obtain PCI resources, aborting\n"); @@ -568,7 +693,6 @@ static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (nhi->hop_count != 12 && nhi->hop_count != 32) dev_warn(&pdev->dev, "unexpected hop count: %d\n", nhi->hop_count); - INIT_WORK(&nhi->interrupt_work, nhi_interrupt_work); nhi->tx_rings = devm_kcalloc(&pdev->dev, nhi->hop_count, sizeof(*nhi->tx_rings), GFP_KERNEL); @@ -577,12 +701,9 @@ static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (!nhi->tx_rings || !nhi->rx_rings) return -ENOMEM; - nhi_disable_interrupts(nhi); /* In case someone left them on. */ - res = devm_request_irq(&pdev->dev, pdev->irq, nhi_msi, - IRQF_NO_SUSPEND, /* must work during _noirq */ - "thunderbolt", nhi); + res = nhi_init_msi(nhi); if (res) { - dev_err(&pdev->dev, "request_irq failed, aborting\n"); + dev_err(&pdev->dev, "cannot enable MSI, aborting\n"); return res; } |