From d1b054da8f599905f3c18a218961dcf17f9d5f13 Mon Sep 17 00:00:00 2001 From: Yu Zhao Date: Fri, 20 Mar 2009 11:25:11 +0800 Subject: PCI: initialize and release SR-IOV capability If a device has the SR-IOV capability, initialize it (set the ARI Capable Hierarchy in the lowest numbered PF if necessary; calculate the System Page Size for the VF MMIO, probe the VF Offset, Stride and BARs). A lock for the VF bus allocation is also initialized if a PF is the lowest numbered PF. Reviewed-by: Matthew Wilcox Signed-off-by: Yu Zhao Signed-off-by: Jesse Barnes --- drivers/pci/iov.c | 182 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 182 insertions(+) create mode 100644 drivers/pci/iov.c (limited to 'drivers/pci/iov.c') diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c new file mode 100644 index 00000000000..66cc414ed15 --- /dev/null +++ b/drivers/pci/iov.c @@ -0,0 +1,182 @@ +/* + * drivers/pci/iov.c + * + * Copyright (C) 2009 Intel Corporation, Yu Zhao + * + * PCI Express I/O Virtualization (IOV) support. + * Single Root IOV 1.0 + */ + +#include +#include +#include +#include +#include "pci.h" + + +static int sriov_init(struct pci_dev *dev, int pos) +{ + int i; + int rc; + int nres; + u32 pgsz; + u16 ctrl, total, offset, stride; + struct pci_sriov *iov; + struct resource *res; + struct pci_dev *pdev; + + if (dev->pcie_type != PCI_EXP_TYPE_RC_END && + dev->pcie_type != PCI_EXP_TYPE_ENDPOINT) + return -ENODEV; + + pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl); + if (ctrl & PCI_SRIOV_CTRL_VFE) { + pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); + ssleep(1); + } + + pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); + if (!total) + return 0; + + ctrl = 0; + list_for_each_entry(pdev, &dev->bus->devices, bus_list) + if (pdev->is_physfn) + goto found; + + pdev = NULL; + if (pci_ari_enabled(dev->bus)) + ctrl |= PCI_SRIOV_CTRL_ARI; + +found: + pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl); + pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, total); + pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset); + pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride); + if (!offset || (total > 1 && !stride)) + return -EIO; + + pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz); + i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0; + pgsz &= ~((1 << i) - 1); + if (!pgsz) + return -EIO; + + pgsz &= ~(pgsz - 1); + pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz); + + nres = 0; + for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { + res = dev->resource + PCI_IOV_RESOURCES + i; + i += __pci_read_base(dev, pci_bar_unknown, res, + pos + PCI_SRIOV_BAR + i * 4); + if (!res->flags) + continue; + if (resource_size(res) & (PAGE_SIZE - 1)) { + rc = -EIO; + goto failed; + } + res->end = res->start + resource_size(res) * total - 1; + nres++; + } + + iov = kzalloc(sizeof(*iov), GFP_KERNEL); + if (!iov) { + rc = -ENOMEM; + goto failed; + } + + iov->pos = pos; + iov->nres = nres; + iov->ctrl = ctrl; + iov->total = total; + iov->offset = offset; + iov->stride = stride; + iov->pgsz = pgsz; + iov->self = dev; + pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap); + pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link); + + if (pdev) + iov->dev = pci_dev_get(pdev); + else { + iov->dev = dev; + mutex_init(&iov->lock); + } + + dev->sriov = iov; + dev->is_physfn = 1; + + return 0; + +failed: + for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { + res = dev->resource + PCI_IOV_RESOURCES + i; + res->flags = 0; + } + + return rc; +} + +static void sriov_release(struct pci_dev *dev) +{ + if (dev == dev->sriov->dev) + mutex_destroy(&dev->sriov->lock); + else + pci_dev_put(dev->sriov->dev); + + kfree(dev->sriov); + dev->sriov = NULL; +} + +/** + * pci_iov_init - initialize the IOV capability + * @dev: the PCI device + * + * Returns 0 on success, or negative on failure. + */ +int pci_iov_init(struct pci_dev *dev) +{ + int pos; + + if (!dev->is_pcie) + return -ENODEV; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV); + if (pos) + return sriov_init(dev, pos); + + return -ENODEV; +} + +/** + * pci_iov_release - release resources used by the IOV capability + * @dev: the PCI device + */ +void pci_iov_release(struct pci_dev *dev) +{ + if (dev->is_physfn) + sriov_release(dev); +} + +/** + * pci_iov_resource_bar - get position of the SR-IOV BAR + * @dev: the PCI device + * @resno: the resource number + * @type: the BAR type to be filled in + * + * Returns position of the BAR encapsulated in the SR-IOV capability. + */ +int pci_iov_resource_bar(struct pci_dev *dev, int resno, + enum pci_bar_type *type) +{ + if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END) + return 0; + + BUG_ON(!dev->is_physfn); + + *type = pci_bar_unknown; + + return dev->sriov->pos + PCI_SRIOV_BAR + + 4 * (resno - PCI_IOV_RESOURCES); +} -- cgit v1.2.3