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-rw-r--r--drivers/pci/pci.c65
-rw-r--r--drivers/pci/pci.h1
-rw-r--r--drivers/pci/probe.c112
-rw-r--r--drivers/pci/quirks.c16
4 files changed, 149 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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 15:56:13 +0100