From fa08a396647767abd24a9e7015cb177121d0cf15 Mon Sep 17 00:00:00 2001 From: Ramachandra Rao Gajula Date: Sat, 11 May 2013 15:19:31 -0700 Subject: NVMe: Add MSI support Some devices only have support for MSI, not MSI-X. While MSI is more limited, it still provides better performance than line-based interrupts. Signed-off-by: Ramachandra Gajula Signed-off-by: Matthew Wilcox --- drivers/block/nvme-core.c | 40 ++++++++++++++++++++++++++++++++-------- 1 file changed, 32 insertions(+), 8 deletions(-) (limited to 'drivers/block/nvme-core.c') diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c index a57d3bcec803..ce79a590b45b 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -1637,7 +1637,8 @@ static int set_queue_count(struct nvme_dev *dev, int count) static int nvme_setup_io_queues(struct nvme_dev *dev) { - int result, cpu, i, nr_io_queues, db_bar_size, q_depth; + struct pci_dev *pdev = dev->pci_dev; + int result, cpu, i, nr_io_queues, db_bar_size, q_depth, q_count; nr_io_queues = num_online_cpus(); result = set_queue_count(dev, nr_io_queues); @@ -1646,14 +1647,14 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) if (result < nr_io_queues) nr_io_queues = result; + q_count = nr_io_queues; /* Deregister the admin queue's interrupt */ free_irq(dev->entry[0].vector, dev->queues[0]); db_bar_size = 4096 + ((nr_io_queues + 1) << (dev->db_stride + 3)); if (db_bar_size > 8192) { iounmap(dev->bar); - dev->bar = ioremap(pci_resource_start(dev->pci_dev, 0), - db_bar_size); + dev->bar = ioremap(pci_resource_start(pdev, 0), db_bar_size); dev->dbs = ((void __iomem *)dev->bar) + 4096; dev->queues[0]->q_db = dev->dbs; } @@ -1661,19 +1662,36 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) for (i = 0; i < nr_io_queues; i++) dev->entry[i].entry = i; for (;;) { - result = pci_enable_msix(dev->pci_dev, dev->entry, - nr_io_queues); + result = pci_enable_msix(pdev, dev->entry, nr_io_queues); if (result == 0) { break; } else if (result > 0) { nr_io_queues = result; continue; } else { - nr_io_queues = 1; + nr_io_queues = 0; break; } } + if (nr_io_queues == 0) { + nr_io_queues = q_count; + for (;;) { + result = pci_enable_msi_block(pdev, nr_io_queues); + if (result == 0) { + for (i = 0; i < nr_io_queues; i++) + dev->entry[i].vector = i + pdev->irq; + break; + } else if (result > 0) { + nr_io_queues = result; + continue; + } else { + nr_io_queues = 1; + break; + } + } + } + result = queue_request_irq(dev, dev->queues[0], "nvme admin"); /* XXX: handle failure here */ @@ -1854,7 +1872,10 @@ static void nvme_free_dev(struct kref *kref) { struct nvme_dev *dev = container_of(kref, struct nvme_dev, kref); nvme_dev_remove(dev); - pci_disable_msix(dev->pci_dev); + if (dev->pci_dev->msi_enabled) + pci_disable_msi(dev->pci_dev); + else if (dev->pci_dev->msix_enabled) + pci_disable_msix(dev->pci_dev); iounmap(dev->bar); nvme_release_instance(dev); nvme_release_prp_pools(dev); @@ -1987,7 +2008,10 @@ static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id) unmap: iounmap(dev->bar); disable_msix: - pci_disable_msix(pdev); + if (dev->pci_dev->msi_enabled) + pci_disable_msi(dev->pci_dev); + else if (dev->pci_dev->msix_enabled) + pci_disable_msix(dev->pci_dev); nvme_release_instance(dev); nvme_release_prp_pools(dev); disable: -- cgit v1.2.3