X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fxen%2Fpcifront%2Fpci_op.c;fp=drivers%2Fxen%2Fpcifront%2Fpci_op.c;h=94015f5d5e32bb95e398798425d45d41e7ba58cf;hb=1db395853d4f30d6120458bd279ede1f882a8525;hp=0000000000000000000000000000000000000000;hpb=34a75f0025b9cf803b6a88db032e6ad6950c9313;p=linux-2.6.git diff --git a/drivers/xen/pcifront/pci_op.c b/drivers/xen/pcifront/pci_op.c new file mode 100644 index 000000000..94015f5d5 --- /dev/null +++ b/drivers/xen/pcifront/pci_op.c @@ -0,0 +1,273 @@ +/* + * PCI Frontend Operations - Communicates with frontend + * + * Author: Ryan Wilson + */ +#include +#include +#include +#include +#include +#include +#include +#include "pcifront.h" + +static int verbose_request = 0; +module_param(verbose_request, int, 0644); + +static int errno_to_pcibios_err(int errno) +{ + switch (errno) { + case XEN_PCI_ERR_success: + return PCIBIOS_SUCCESSFUL; + + case XEN_PCI_ERR_dev_not_found: + return PCIBIOS_DEVICE_NOT_FOUND; + + case XEN_PCI_ERR_invalid_offset: + case XEN_PCI_ERR_op_failed: + return PCIBIOS_BAD_REGISTER_NUMBER; + + case XEN_PCI_ERR_not_implemented: + return PCIBIOS_FUNC_NOT_SUPPORTED; + + case XEN_PCI_ERR_access_denied: + return PCIBIOS_SET_FAILED; + } + return errno; +} + +static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op) +{ + int err = 0; + struct xen_pci_op *active_op = &pdev->sh_info->op; + unsigned long irq_flags; + evtchn_port_t port = pdev->evtchn; + s64 ns, ns_timeout; + struct timeval tv; + + spin_lock_irqsave(&pdev->sh_info_lock, irq_flags); + + memcpy(active_op, op, sizeof(struct xen_pci_op)); + + /* Go */ + wmb(); + set_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags); + notify_remote_via_evtchn(port); + + /* + * We set a poll timeout of 3 seconds but give up on return after + * 2 seconds. It is better to time out too late rather than too early + * (in the latter case we end up continually re-executing poll() with a + * timeout in the past). 1s difference gives plenty of slack for error. + */ + do_gettimeofday(&tv); + ns_timeout = timeval_to_ns(&tv) + 2 * NSEC_PER_SEC; + + clear_evtchn(port); + + while (test_bit(_XEN_PCIF_active, + (unsigned long *)&pdev->sh_info->flags)) { + if (HYPERVISOR_poll(&port, 1, jiffies + 3*HZ)) + BUG(); + clear_evtchn(port); + do_gettimeofday(&tv); + ns = timeval_to_ns(&tv); + if (ns > ns_timeout) { + dev_err(&pdev->xdev->dev, + "pciback not responding!!!\n"); + clear_bit(_XEN_PCIF_active, + (unsigned long *)&pdev->sh_info->flags); + err = XEN_PCI_ERR_dev_not_found; + goto out; + } + } + + memcpy(op, active_op, sizeof(struct xen_pci_op)); + + err = op->err; + out: + spin_unlock_irqrestore(&pdev->sh_info_lock, irq_flags); + return err; +} + +/* Access to this function is spinlocked in drivers/pci/access.c */ +static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 * val) +{ + int err = 0; + struct xen_pci_op op = { + .cmd = XEN_PCI_OP_conf_read, + .domain = pci_domain_nr(bus), + .bus = bus->number, + .devfn = devfn, + .offset = where, + .size = size, + }; + struct pcifront_sd *sd = bus->sysdata; + struct pcifront_device *pdev = pcifront_get_pdev(sd); + + if (verbose_request) + dev_info(&pdev->xdev->dev, + "read dev=%04x:%02x:%02x.%01x - offset %x size %d\n", + pci_domain_nr(bus), bus->number, PCI_SLOT(devfn), + PCI_FUNC(devfn), where, size); + + err = do_pci_op(pdev, &op); + + if (likely(!err)) { + if (verbose_request) + dev_info(&pdev->xdev->dev, "read got back value %x\n", + op.value); + + *val = op.value; + } else if (err == -ENODEV) { + /* No device here, pretend that it just returned 0 */ + err = 0; + *val = 0; + } + + return errno_to_pcibios_err(err); +} + +/* Access to this function is spinlocked in drivers/pci/access.c */ +static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 val) +{ + struct xen_pci_op op = { + .cmd = XEN_PCI_OP_conf_write, + .domain = pci_domain_nr(bus), + .bus = bus->number, + .devfn = devfn, + .offset = where, + .size = size, + .value = val, + }; + struct pcifront_sd *sd = bus->sysdata; + struct pcifront_device *pdev = pcifront_get_pdev(sd); + + if (verbose_request) + dev_info(&pdev->xdev->dev, + "write dev=%04x:%02x:%02x.%01x - " + "offset %x size %d val %x\n", + pci_domain_nr(bus), bus->number, + PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val); + + return errno_to_pcibios_err(do_pci_op(pdev, &op)); +} + +struct pci_ops pcifront_bus_ops = { + .read = pcifront_bus_read, + .write = pcifront_bus_write, +}; + +/* Claim resources for the PCI frontend as-is, backend won't allow changes */ +static void pcifront_claim_resource(struct pci_dev *dev, void *data) +{ + struct pcifront_device *pdev = data; + int i; + struct resource *r; + + for (i = 0; i < PCI_NUM_RESOURCES; i++) { + r = &dev->resource[i]; + + if (!r->parent && r->start && r->flags) { + dev_dbg(&pdev->xdev->dev, "claiming resource %s/%d\n", + pci_name(dev), i); + pci_claim_resource(dev, i); + } + } +} + +int pcifront_scan_root(struct pcifront_device *pdev, + unsigned int domain, unsigned int bus) +{ + struct pci_bus *b; + struct pcifront_sd *sd = NULL; + struct pci_bus_entry *bus_entry = NULL; + int err = 0; + +#ifndef CONFIG_PCI_DOMAINS + if (domain != 0) { + dev_err(&pdev->xdev->dev, + "PCI Root in non-zero PCI Domain! domain=%d\n", domain); + dev_err(&pdev->xdev->dev, + "Please compile with CONFIG_PCI_DOMAINS\n"); + err = -EINVAL; + goto err_out; + } +#endif + + dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n", + domain, bus); + + bus_entry = kmalloc(sizeof(*bus_entry), GFP_KERNEL); + sd = kmalloc(sizeof(*sd), GFP_KERNEL); + if (!bus_entry || !sd) { + err = -ENOMEM; + goto err_out; + } + pcifront_init_sd(sd, domain, pdev); + + b = pci_scan_bus_parented(&pdev->xdev->dev, bus, + &pcifront_bus_ops, sd); + if (!b) { + dev_err(&pdev->xdev->dev, + "Error creating PCI Frontend Bus!\n"); + err = -ENOMEM; + goto err_out; + } + bus_entry->bus = b; + + list_add(&bus_entry->list, &pdev->root_buses); + + /* Claim resources before going "live" with our devices */ + pci_walk_bus(b, pcifront_claim_resource, pdev); + + pci_bus_add_devices(b); + + return 0; + + err_out: + kfree(bus_entry); + kfree(sd); + + return err; +} + +static void free_root_bus_devs(struct pci_bus *bus) +{ + struct pci_dev *dev; + + spin_lock(&pci_bus_lock); + while (!list_empty(&bus->devices)) { + dev = container_of(bus->devices.next, struct pci_dev, bus_list); + spin_unlock(&pci_bus_lock); + + dev_dbg(&dev->dev, "removing device\n"); + pci_remove_bus_device(dev); + + spin_lock(&pci_bus_lock); + } + spin_unlock(&pci_bus_lock); +} + +void pcifront_free_roots(struct pcifront_device *pdev) +{ + struct pci_bus_entry *bus_entry, *t; + + dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n"); + + list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) { + list_del(&bus_entry->list); + + free_root_bus_devs(bus_entry->bus); + + kfree(bus_entry->bus->sysdata); + + device_unregister(bus_entry->bus->bridge); + pci_remove_bus(bus_entry->bus); + + kfree(bus_entry); + } +}