diff options
Diffstat (limited to 'drivers/pci/iov.c')
| -rw-r--r-- | drivers/pci/iov.c | 737 |
1 files changed, 737 insertions, 0 deletions
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c new file mode 100644 index 00000000..6554e1a0 --- /dev/null +++ b/drivers/pci/iov.c @@ -0,0 +1,737 @@ +/* + * drivers/pci/iov.c + * + * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com> + * + * PCI Express I/O Virtualization (IOV) support. + * Single Root IOV 1.0 + * Address Translation Service 1.0 + */ + +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/mutex.h> +#include <linux/export.h> +#include <linux/string.h> +#include <linux/delay.h> +#include <linux/pci-ats.h> +#include "pci.h" + +#define VIRTFN_ID_LEN 16 + +static inline u8 virtfn_bus(struct pci_dev *dev, int id) +{ + return dev->bus->number + ((dev->devfn + dev->sriov->offset + + dev->sriov->stride * id) >> 8); +} + +static inline u8 virtfn_devfn(struct pci_dev *dev, int id) +{ + return (dev->devfn + dev->sriov->offset + + dev->sriov->stride * id) & 0xff; +} + +static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr) +{ + int rc; + struct pci_bus *child; + + if (bus->number == busnr) + return bus; + + child = pci_find_bus(pci_domain_nr(bus), busnr); + if (child) + return child; + + child = pci_add_new_bus(bus, NULL, busnr); + if (!child) + return NULL; + + child->subordinate = busnr; + child->dev.parent = bus->bridge; + rc = pci_bus_add_child(child); + if (rc) { + pci_remove_bus(child); + return NULL; + } + + return child; +} + +static void virtfn_remove_bus(struct pci_bus *bus, int busnr) +{ + struct pci_bus *child; + + if (bus->number == busnr) + return; + + child = pci_find_bus(pci_domain_nr(bus), busnr); + BUG_ON(!child); + + if (list_empty(&child->devices)) + pci_remove_bus(child); +} + +static int virtfn_add(struct pci_dev *dev, int id, int reset) +{ + int i; + int rc; + u64 size; + char buf[VIRTFN_ID_LEN]; + struct pci_dev *virtfn; + struct resource *res; + struct pci_sriov *iov = dev->sriov; + + virtfn = alloc_pci_dev(); + if (!virtfn) + return -ENOMEM; + + mutex_lock(&iov->dev->sriov->lock); + virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id)); + if (!virtfn->bus) { + kfree(virtfn); + mutex_unlock(&iov->dev->sriov->lock); + return -ENOMEM; + } + virtfn->devfn = virtfn_devfn(dev, id); + virtfn->vendor = dev->vendor; + pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device); + pci_setup_device(virtfn); + virtfn->dev.parent = dev->dev.parent; + + for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { + res = dev->resource + PCI_IOV_RESOURCES + i; + if (!res->parent) + continue; + virtfn->resource[i].name = pci_name(virtfn); + virtfn->resource[i].flags = res->flags; + size = resource_size(res); + do_div(size, iov->total); + virtfn->resource[i].start = res->start + size * id; + virtfn->resource[i].end = virtfn->resource[i].start + size - 1; + rc = request_resource(res, &virtfn->resource[i]); + BUG_ON(rc); + } + + if (reset) + __pci_reset_function(virtfn); + + pci_device_add(virtfn, virtfn->bus); + mutex_unlock(&iov->dev->sriov->lock); + + virtfn->physfn = pci_dev_get(dev); + virtfn->is_virtfn = 1; + + rc = pci_bus_add_device(virtfn); + if (rc) + goto failed1; + sprintf(buf, "virtfn%u", id); + rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf); + if (rc) + goto failed1; + rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn"); + if (rc) + goto failed2; + + kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE); + + return 0; + +failed2: + sysfs_remove_link(&dev->dev.kobj, buf); +failed1: + pci_dev_put(dev); + mutex_lock(&iov->dev->sriov->lock); + pci_stop_and_remove_bus_device(virtfn); + virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); + mutex_unlock(&iov->dev->sriov->lock); + + return rc; +} + +static void virtfn_remove(struct pci_dev *dev, int id, int reset) +{ + char buf[VIRTFN_ID_LEN]; + struct pci_bus *bus; + struct pci_dev *virtfn; + struct pci_sriov *iov = dev->sriov; + + bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id)); + if (!bus) + return; + + virtfn = pci_get_slot(bus, virtfn_devfn(dev, id)); + if (!virtfn) + return; + + pci_dev_put(virtfn); + + if (reset) { + device_release_driver(&virtfn->dev); + __pci_reset_function(virtfn); + } + + sprintf(buf, "virtfn%u", id); + sysfs_remove_link(&dev->dev.kobj, buf); + /* + * pci_stop_dev() could have been called for this virtfn already, + * so the directory for the virtfn may have been removed before. + * Double check to avoid spurious sysfs warnings. + */ + if (virtfn->dev.kobj.sd) + sysfs_remove_link(&virtfn->dev.kobj, "physfn"); + + mutex_lock(&iov->dev->sriov->lock); + pci_stop_and_remove_bus_device(virtfn); + virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); + mutex_unlock(&iov->dev->sriov->lock); + + pci_dev_put(dev); +} + +static int sriov_migration(struct pci_dev *dev) +{ + u16 status; + struct pci_sriov *iov = dev->sriov; + + if (!iov->nr_virtfn) + return 0; + + if (!(iov->cap & PCI_SRIOV_CAP_VFM)) + return 0; + + pci_read_config_word(dev, iov->pos + PCI_SRIOV_STATUS, &status); + if (!(status & PCI_SRIOV_STATUS_VFM)) + return 0; + + schedule_work(&iov->mtask); + + return 1; +} + +static void sriov_migration_task(struct work_struct *work) +{ + int i; + u8 state; + u16 status; + struct pci_sriov *iov = container_of(work, struct pci_sriov, mtask); + + for (i = iov->initial; i < iov->nr_virtfn; i++) { + state = readb(iov->mstate + i); + if (state == PCI_SRIOV_VFM_MI) { + writeb(PCI_SRIOV_VFM_AV, iov->mstate + i); + state = readb(iov->mstate + i); + if (state == PCI_SRIOV_VFM_AV) + virtfn_add(iov->self, i, 1); + } else if (state == PCI_SRIOV_VFM_MO) { + virtfn_remove(iov->self, i, 1); + writeb(PCI_SRIOV_VFM_UA, iov->mstate + i); + state = readb(iov->mstate + i); + if (state == PCI_SRIOV_VFM_AV) + virtfn_add(iov->self, i, 0); + } + } + + pci_read_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, &status); + status &= ~PCI_SRIOV_STATUS_VFM; + pci_write_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, status); +} + +static int sriov_enable_migration(struct pci_dev *dev, int nr_virtfn) +{ + int bir; + u32 table; + resource_size_t pa; + struct pci_sriov *iov = dev->sriov; + + if (nr_virtfn <= iov->initial) + return 0; + + pci_read_config_dword(dev, iov->pos + PCI_SRIOV_VFM, &table); + bir = PCI_SRIOV_VFM_BIR(table); + if (bir > PCI_STD_RESOURCE_END) + return -EIO; + + table = PCI_SRIOV_VFM_OFFSET(table); + if (table + nr_virtfn > pci_resource_len(dev, bir)) + return -EIO; + + pa = pci_resource_start(dev, bir) + table; + iov->mstate = ioremap(pa, nr_virtfn); + if (!iov->mstate) + return -ENOMEM; + + INIT_WORK(&iov->mtask, sriov_migration_task); + + iov->ctrl |= PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR; + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + + return 0; +} + +static void sriov_disable_migration(struct pci_dev *dev) +{ + struct pci_sriov *iov = dev->sriov; + + iov->ctrl &= ~(PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + + cancel_work_sync(&iov->mtask); + iounmap(iov->mstate); +} + +static int sriov_enable(struct pci_dev *dev, int nr_virtfn) +{ + int rc; + int i, j; + int nres; + u16 offset, stride, initial; + struct resource *res; + struct pci_dev *pdev; + struct pci_sriov *iov = dev->sriov; + int bars = 0; + + if (!nr_virtfn) + return 0; + + if (iov->nr_virtfn) + return -EINVAL; + + pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial); + if (initial > iov->total || + (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total))) + return -EIO; + + if (nr_virtfn < 0 || nr_virtfn > iov->total || + (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial))) + return -EINVAL; + + pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn); + pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset); + pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride); + if (!offset || (nr_virtfn > 1 && !stride)) + return -EIO; + + nres = 0; + for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { + bars |= (1 << (i + PCI_IOV_RESOURCES)); + res = dev->resource + PCI_IOV_RESOURCES + i; + if (res->parent) + nres++; + } + if (nres != iov->nres) { + dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n"); + return -ENOMEM; + } + + iov->offset = offset; + iov->stride = stride; + + if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->subordinate) { + dev_err(&dev->dev, "SR-IOV: bus number out of range\n"); + return -ENOMEM; + } + + if (pci_enable_resources(dev, bars)) { + dev_err(&dev->dev, "SR-IOV: IOV BARS not allocated\n"); + return -ENOMEM; + } + + if (iov->link != dev->devfn) { + pdev = pci_get_slot(dev->bus, iov->link); + if (!pdev) + return -ENODEV; + + pci_dev_put(pdev); + + if (!pdev->is_physfn) + return -ENODEV; + + rc = sysfs_create_link(&dev->dev.kobj, + &pdev->dev.kobj, "dep_link"); + if (rc) + return rc; + } + + iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; + pci_cfg_access_lock(dev); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + msleep(100); + pci_cfg_access_unlock(dev); + + iov->initial = initial; + if (nr_virtfn < initial) + initial = nr_virtfn; + + for (i = 0; i < initial; i++) { + rc = virtfn_add(dev, i, 0); + if (rc) + goto failed; + } + + if (iov->cap & PCI_SRIOV_CAP_VFM) { + rc = sriov_enable_migration(dev, nr_virtfn); + if (rc) + goto failed; + } + + kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE); + iov->nr_virtfn = nr_virtfn; + + return 0; + +failed: + for (j = 0; j < i; j++) + virtfn_remove(dev, j, 0); + + iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); + pci_cfg_access_lock(dev); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + ssleep(1); + pci_cfg_access_unlock(dev); + + if (iov->link != dev->devfn) + sysfs_remove_link(&dev->dev.kobj, "dep_link"); + + return rc; +} + +static void sriov_disable(struct pci_dev *dev) +{ + int i; + struct pci_sriov *iov = dev->sriov; + + if (!iov->nr_virtfn) + return; + + if (iov->cap & PCI_SRIOV_CAP_VFM) + sriov_disable_migration(dev); + + for (i = 0; i < iov->nr_virtfn; i++) + virtfn_remove(dev, i, 0); + + iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); + pci_cfg_access_lock(dev); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + ssleep(1); + pci_cfg_access_unlock(dev); + + if (iov->link != dev->devfn) + sysfs_remove_link(&dev->dev.kobj, "dep_link"); + + iov->nr_virtfn = 0; +} + +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_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 (dev->pcie_type == PCI_EXP_TYPE_RC_END) + iov->link = PCI_DEVFN(PCI_SLOT(dev->devfn), 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) +{ + BUG_ON(dev->sriov->nr_virtfn); + + if (dev != dev->sriov->dev) + pci_dev_put(dev->sriov->dev); + + mutex_destroy(&dev->sriov->lock); + + kfree(dev->sriov); + dev->sriov = NULL; +} + +static void sriov_restore_state(struct pci_dev *dev) +{ + int i; + u16 ctrl; + struct pci_sriov *iov = dev->sriov; + + pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl); + if (ctrl & PCI_SRIOV_CTRL_VFE) + return; + + for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) + pci_update_resource(dev, i); + + pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->nr_virtfn); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + if (iov->ctrl & PCI_SRIOV_CTRL_VFE) + msleep(100); +} + +/** + * 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 (!pci_is_pcie(dev)) + 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); +} + +/** + * pci_sriov_resource_alignment - get resource alignment for VF BAR + * @dev: the PCI device + * @resno: the resource number + * + * Returns the alignment of the VF BAR found in the SR-IOV capability. + * This is not the same as the resource size which is defined as + * the VF BAR size multiplied by the number of VFs. The alignment + * is just the VF BAR size. + */ +resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno) +{ + struct resource tmp; + enum pci_bar_type type; + int reg = pci_iov_resource_bar(dev, resno, &type); + + if (!reg) + return 0; + + __pci_read_base(dev, type, &tmp, reg); + return resource_alignment(&tmp); +} + +/** + * pci_restore_iov_state - restore the state of the IOV capability + * @dev: the PCI device + */ +void pci_restore_iov_state(struct pci_dev *dev) +{ + if (dev->is_physfn) + sriov_restore_state(dev); +} + +/** + * pci_iov_bus_range - find bus range used by Virtual Function + * @bus: the PCI bus + * + * Returns max number of buses (exclude current one) used by Virtual + * Functions. + */ +int pci_iov_bus_range(struct pci_bus *bus) +{ + int max = 0; + u8 busnr; + struct pci_dev *dev; + + list_for_each_entry(dev, &bus->devices, bus_list) { + if (!dev->is_physfn) + continue; + busnr = virtfn_bus(dev, dev->sriov->total - 1); + if (busnr > max) + max = busnr; + } + + return max ? max - bus->number : 0; +} + +/** + * pci_enable_sriov - enable the SR-IOV capability + * @dev: the PCI device + * @nr_virtfn: number of virtual functions to enable + * + * Returns 0 on success, or negative on failure. + */ +int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) +{ + might_sleep(); + + if (!dev->is_physfn) + return -ENODEV; + + return sriov_enable(dev, nr_virtfn); +} +EXPORT_SYMBOL_GPL(pci_enable_sriov); + +/** + * pci_disable_sriov - disable the SR-IOV capability + * @dev: the PCI device + */ +void pci_disable_sriov(struct pci_dev *dev) +{ + might_sleep(); + + if (!dev->is_physfn) + return; + + sriov_disable(dev); +} +EXPORT_SYMBOL_GPL(pci_disable_sriov); + +/** + * pci_sriov_migration - notify SR-IOV core of Virtual Function Migration + * @dev: the PCI device + * + * Returns IRQ_HANDLED if the IRQ is handled, or IRQ_NONE if not. + * + * Physical Function driver is responsible to register IRQ handler using + * VF Migration Interrupt Message Number, and call this function when the + * interrupt is generated by the hardware. + */ +irqreturn_t pci_sriov_migration(struct pci_dev *dev) +{ + if (!dev->is_physfn) + return IRQ_NONE; + + return sriov_migration(dev) ? IRQ_HANDLED : IRQ_NONE; +} +EXPORT_SYMBOL_GPL(pci_sriov_migration); + +/** + * pci_num_vf - return number of VFs associated with a PF device_release_driver + * @dev: the PCI device + * + * Returns number of VFs, or 0 if SR-IOV is not enabled. + */ +int pci_num_vf(struct pci_dev *dev) +{ + if (!dev || !dev->is_physfn) + return 0; + else + return dev->sriov->nr_virtfn; +} +EXPORT_SYMBOL_GPL(pci_num_vf); |