diff options
| -rw-r--r-- | drivers/pci/pci.c | 65 | ||||
| -rw-r--r-- | drivers/pci/pci.h | 1 | ||||
| -rw-r--r-- | drivers/pci/probe.c | 112 | ||||
| -rw-r--r-- | drivers/pci/quirks.c | 16 | ||||
| -rw-r--r-- | include/linux/pci.h | 1 |
5 files changed, 150 insertions, 45 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index af0cc3456dc1..827a9f99a8e5 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -52,6 +52,7 @@ static void pci_pme_list_scan(struct work_struct *work); static LIST_HEAD(pci_pme_list); static DEFINE_MUTEX(pci_pme_list_mutex); static DECLARE_DELAYED_WORK(pci_pme_work, pci_pme_list_scan); +static DEFINE_MUTEX(pci_bridge_mutex); struct pci_pme_device { struct list_head list; @@ -1348,10 +1349,16 @@ static void pci_enable_bridge(struct pci_dev *dev) if (bridge) pci_enable_bridge(bridge); + /* + * Hold pci_bridge_mutex to prevent a race when enabling two + * devices below the bridge simultaneously. The race may cause a + * PCI_COMMAND_MEMORY update to be lost (see changelog). + */ + mutex_lock(&pci_bridge_mutex); if (pci_is_enabled(dev)) { if (!dev->is_busmaster) pci_set_master(dev); - return; + goto end; } retval = pci_enable_device(dev); @@ -1359,6 +1366,8 @@ static void pci_enable_bridge(struct pci_dev *dev) dev_err(&dev->dev, "Error enabling bridge (%d), continuing\n", retval); pci_set_master(dev); +end: + mutex_unlock(&pci_bridge_mutex); } static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags) @@ -1383,7 +1392,7 @@ static int pci_enable_device_flags(struct pci_dev *dev, unsigned long flags) return 0; /* already enabled */ bridge = pci_upstream_bridge(dev); - if (bridge) + if (bridge && !pci_is_enabled(bridge)) pci_enable_bridge(bridge); /* only skip sriov related */ @@ -3811,27 +3820,49 @@ int pci_wait_for_pending_transaction(struct pci_dev *dev) } EXPORT_SYMBOL(pci_wait_for_pending_transaction); -/* - * We should only need to wait 100ms after FLR, but some devices take longer. - * Wait for up to 1000ms for config space to return something other than -1. - * Intel IGD requires this when an LCD panel is attached. We read the 2nd - * dword because VFs don't implement the 1st dword. - */ static void pci_flr_wait(struct pci_dev *dev) { - int i = 0; + int delay = 1, timeout = 60000; u32 id; - do { - msleep(100); + /* + * Per PCIe r3.1, sec 6.6.2, a device must complete an FLR within + * 100ms, but may silently discard requests while the FLR is in + * progress. Wait 100ms before trying to access the device. + */ + msleep(100); + + /* + * After 100ms, the device should not silently discard config + * requests, but it may still indicate that it needs more time by + * responding to them with CRS completions. The Root Port will + * generally synthesize ~0 data to complete the read (except when + * CRS SV is enabled and the read was for the Vendor ID; in that + * case it synthesizes 0x0001 data). + * + * Wait for the device to return a non-CRS completion. Read the + * Command register instead of Vendor ID so we don't have to + * contend with the CRS SV value. + */ + pci_read_config_dword(dev, PCI_COMMAND, &id); + while (id == ~0) { + if (delay > timeout) { + dev_warn(&dev->dev, "not ready %dms after FLR; giving up\n", + 100 + delay - 1); + return; + } + + if (delay > 1000) + dev_info(&dev->dev, "not ready %dms after FLR; waiting\n", + 100 + delay - 1); + + msleep(delay); + delay *= 2; pci_read_config_dword(dev, PCI_COMMAND, &id); - } while (i++ < 10 && id == ~0); + } - if (id == ~0) - dev_warn(&dev->dev, "Failed to return from FLR\n"); - else if (i > 1) - dev_info(&dev->dev, "Required additional %dms to return from FLR\n", - (i - 1) * 100); + if (delay > 1000) + dev_info(&dev->dev, "ready %dms after FLR\n", 100 + delay - 1); } /** diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 22e061738c6f..a6560c9baa52 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -235,6 +235,7 @@ enum pci_bar_type { pci_bar_mem64, /* A 64-bit memory BAR */ }; +int pci_configure_extended_tags(struct pci_dev *dev, void *ign); bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *pl, int crs_timeout); int pci_setup_device(struct pci_dev *dev); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index c31310db0404..9b8a445b9294 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1745,21 +1745,50 @@ static void program_hpp_type2(struct pci_dev *dev, struct hpp_type2 *hpp) */ } -static void pci_configure_extended_tags(struct pci_dev *dev) +int pci_configure_extended_tags(struct pci_dev *dev, void *ign) { - u32 dev_cap; + struct pci_host_bridge *host; + u32 cap; + u16 ctl; int ret; if (!pci_is_pcie(dev)) - return; + return 0; - ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &dev_cap); + ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap); if (ret) - return; + return 0; - if (dev_cap & PCI_EXP_DEVCAP_EXT_TAG) + if (!(cap & PCI_EXP_DEVCAP_EXT_TAG)) + return 0; + + ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl); + if (ret) + return 0; + + host = pci_find_host_bridge(dev->bus); + if (!host) + return 0; + + /* + * If some device in the hierarchy doesn't handle Extended Tags + * correctly, make sure they're disabled. + */ + if (host->no_ext_tags) { + if (ctl & PCI_EXP_DEVCTL_EXT_TAG) { + dev_info(&dev->dev, "disabling Extended Tags\n"); + pcie_capability_clear_word(dev, PCI_EXP_DEVCTL, + PCI_EXP_DEVCTL_EXT_TAG); + } + return 0; + } + + if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) { + dev_info(&dev->dev, "enabling Extended Tags\n"); pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_EXT_TAG); + } + return 0; } static void pci_configure_device(struct pci_dev *dev) @@ -1768,7 +1797,7 @@ static void pci_configure_device(struct pci_dev *dev) int ret; pci_configure_mps(dev); - pci_configure_extended_tags(dev); + pci_configure_extended_tags(dev, NULL); memset(&hpp, 0, sizeof(hpp)); ret = pci_get_hp_params(dev, &hpp); @@ -1824,42 +1853,69 @@ struct pci_dev *pci_alloc_dev(struct pci_bus *bus) } EXPORT_SYMBOL(pci_alloc_dev); -bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, - int crs_timeout) +static bool pci_bus_crs_vendor_id(u32 l) +{ + return (l & 0xffff) == 0x0001; +} + +static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l, + int timeout) { int delay = 1; - if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) - return false; + if (!pci_bus_crs_vendor_id(*l)) + return true; /* not a CRS completion */ - /* some broken boards return 0 or ~0 if a slot is empty: */ - if (*l == 0xffffffff || *l == 0x00000000 || - *l == 0x0000ffff || *l == 0xffff0000) - return false; + if (!timeout) + return false; /* CRS, but caller doesn't want to wait */ /* - * Configuration Request Retry Status. Some root ports return the - * actual device ID instead of the synthetic ID (0xFFFF) required - * by the PCIe spec. Ignore the device ID and only check for - * (vendor id == 1). + * We got the reserved Vendor ID that indicates a completion with + * Configuration Request Retry Status (CRS). Retry until we get a + * valid Vendor ID or we time out. */ - while ((*l & 0xffff) == 0x0001) { - if (!crs_timeout) + while (pci_bus_crs_vendor_id(*l)) { + if (delay > timeout) { + pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n", + pci_domain_nr(bus), bus->number, + PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1); + return false; + } + if (delay >= 1000) + pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n", + pci_domain_nr(bus), bus->number, + PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1); msleep(delay); delay *= 2; + if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) return false; - /* Card hasn't responded in 60 seconds? Must be stuck. */ - if (delay > crs_timeout) { - printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not responding\n", - pci_domain_nr(bus), bus->number, PCI_SLOT(devfn), - PCI_FUNC(devfn)); - return false; - } } + if (delay >= 1000) + pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n", + pci_domain_nr(bus), bus->number, + PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1); + + return true; +} + +bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, + int timeout) +{ + if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) + return false; + + /* some broken boards return 0 or ~0 if a slot is empty: */ + if (*l == 0xffffffff || *l == 0x00000000 || + *l == 0x0000ffff || *l == 0xffff0000) + return false; + + if (pci_bus_crs_vendor_id(*l)) + return pci_bus_wait_crs(bus, devfn, l, timeout); + return true; } EXPORT_SYMBOL(pci_bus_read_dev_vendor_id); diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 0b0a2ae9a853..3fc0c3adc930 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -4664,3 +4664,19 @@ static void quirk_intel_no_flr(struct pci_dev *dev) } DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1502, quirk_intel_no_flr); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1503, quirk_intel_no_flr); + +static void quirk_no_ext_tags(struct pci_dev *pdev) +{ + struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus); + + if (!bridge) + return; + + bridge->no_ext_tags = 1; + dev_info(&pdev->dev, "disabling Extended Tags (this device can't handle them)\n"); + + pci_walk_bus(bridge->bus, pci_configure_extended_tags, NULL); +} +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0140, quirk_no_ext_tags); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0142, quirk_no_ext_tags); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, 0x0144, quirk_no_ext_tags); diff --git a/include/linux/pci.h b/include/linux/pci.h index bbc2a991b63f..bd3c6264841d 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -473,6 +473,7 @@ struct pci_host_bridge { void *release_data; struct msi_controller *msi; unsigned int ignore_reset_delay:1; /* for entire hierarchy */ + unsigned int no_ext_tags:1; /* no Extended Tags */ /* Resource alignment requirements */ resource_size_t (*align_resource)(struct pci_dev *dev, const struct resource *res, |