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path: root/drivers/pci/probe.c
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Diffstat (limited to 'drivers/pci/probe.c')
-rw-r--r--drivers/pci/probe.c195
1 files changed, 125 insertions, 70 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 70f10fa3c1b2..eeb50bd62402 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -96,7 +96,7 @@ static void release_pcibus_dev(struct device *dev)
static struct class pcibus_class = {
.name = "pci_bus",
.dev_release = &release_pcibus_dev,
- .dev_attrs = pcibus_dev_attrs,
+ .dev_groups = pcibus_groups,
};
static int __init pcibus_class_init(void)
@@ -156,6 +156,8 @@ static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
return flags;
}
+#define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
+
/**
* pci_read_base - read a PCI BAR
* @dev: the PCI device
@@ -170,7 +172,7 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
{
u32 l, sz, mask;
u16 orig_cmd;
- struct pci_bus_region region;
+ struct pci_bus_region region, inverted_region;
bool bar_too_big = false, bar_disabled = false;
mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
@@ -178,8 +180,10 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
/* No printks while decoding is disabled! */
if (!dev->mmio_always_on) {
pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
- pci_write_config_word(dev, PCI_COMMAND,
- orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO));
+ if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
+ pci_write_config_word(dev, PCI_COMMAND,
+ orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
+ }
}
res->name = pci_name(dev);
@@ -250,12 +254,10 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
pci_write_config_dword(dev, pos + 4, 0);
region.start = 0;
region.end = sz64;
- pcibios_bus_to_resource(dev, res, &region);
bar_disabled = true;
} else {
region.start = l64;
region.end = l64 + sz64;
- pcibios_bus_to_resource(dev, res, &region);
}
} else {
sz = pci_size(l, sz, mask);
@@ -265,7 +267,28 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
region.start = l;
region.end = l + sz;
- pcibios_bus_to_resource(dev, res, &region);
+ }
+
+ pcibios_bus_to_resource(dev, res, &region);
+ pcibios_resource_to_bus(dev, &inverted_region, res);
+
+ /*
+ * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
+ * the corresponding resource address (the physical address used by
+ * the CPU. Converting that resource address back to a bus address
+ * should yield the original BAR value:
+ *
+ * resource_to_bus(bus_to_resource(A)) == A
+ *
+ * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
+ * be claimed by the device.
+ */
+ if (inverted_region.start != region.start) {
+ dev_info(&dev->dev, "reg 0x%x: initial BAR value %pa invalid; forcing reassignment\n",
+ pos, &region.start);
+ res->flags |= IORESOURCE_UNSET;
+ res->end -= res->start;
+ res->start = 0;
}
goto out;
@@ -274,13 +297,14 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
fail:
res->flags = 0;
out:
- if (!dev->mmio_always_on)
+ if (!dev->mmio_always_on &&
+ (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
if (bar_too_big)
- dev_err(&dev->dev, "reg %x: can't handle 64-bit BAR\n", pos);
+ dev_err(&dev->dev, "reg 0x%x: can't handle 64-bit BAR\n", pos);
if (res->flags && !bar_disabled)
- dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n", pos, res);
+ dev_printk(KERN_DEBUG, &dev->dev, "reg 0x%x: %pR\n", pos, res);
return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
}
@@ -451,33 +475,46 @@ void pci_read_bridge_bases(struct pci_bus *child)
}
}
-static struct pci_bus * pci_alloc_bus(void)
+static struct pci_bus *pci_alloc_bus(void)
{
struct pci_bus *b;
b = kzalloc(sizeof(*b), GFP_KERNEL);
- if (b) {
- INIT_LIST_HEAD(&b->node);
- INIT_LIST_HEAD(&b->children);
- INIT_LIST_HEAD(&b->devices);
- INIT_LIST_HEAD(&b->slots);
- INIT_LIST_HEAD(&b->resources);
- b->max_bus_speed = PCI_SPEED_UNKNOWN;
- b->cur_bus_speed = PCI_SPEED_UNKNOWN;
- }
+ if (!b)
+ return NULL;
+
+ INIT_LIST_HEAD(&b->node);
+ INIT_LIST_HEAD(&b->children);
+ INIT_LIST_HEAD(&b->devices);
+ INIT_LIST_HEAD(&b->slots);
+ INIT_LIST_HEAD(&b->resources);
+ b->max_bus_speed = PCI_SPEED_UNKNOWN;
+ b->cur_bus_speed = PCI_SPEED_UNKNOWN;
return b;
}
+static void pci_release_host_bridge_dev(struct device *dev)
+{
+ struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
+
+ if (bridge->release_fn)
+ bridge->release_fn(bridge);
+
+ pci_free_resource_list(&bridge->windows);
+
+ kfree(bridge);
+}
+
static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
{
struct pci_host_bridge *bridge;
bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
- if (bridge) {
- INIT_LIST_HEAD(&bridge->windows);
- bridge->bus = b;
- }
+ if (!bridge)
+ return NULL;
+ INIT_LIST_HEAD(&bridge->windows);
+ bridge->bus = b;
return bridge;
}
@@ -1132,6 +1169,8 @@ static void pci_release_dev(struct device *dev)
pci_dev = to_pci_dev(dev);
pci_release_capabilities(pci_dev);
pci_release_of_node(pci_dev);
+ pcibios_release_device(pci_dev);
+ pci_bus_put(pci_dev->bus);
kfree(pci_dev);
}
@@ -1188,19 +1227,7 @@ int pci_cfg_space_size(struct pci_dev *dev)
return PCI_CFG_SPACE_SIZE;
}
-static void pci_release_bus_bridge_dev(struct device *dev)
-{
- struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
-
- if (bridge->release_fn)
- bridge->release_fn(bridge);
-
- pci_free_resource_list(&bridge->windows);
-
- kfree(bridge);
-}
-
-struct pci_dev *alloc_pci_dev(void)
+struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
{
struct pci_dev *dev;
@@ -1210,9 +1237,16 @@ struct pci_dev *alloc_pci_dev(void)
INIT_LIST_HEAD(&dev->bus_list);
dev->dev.type = &pci_dev_type;
+ dev->bus = pci_bus_get(bus);
return dev;
}
+EXPORT_SYMBOL(pci_alloc_dev);
+
+struct pci_dev *alloc_pci_dev(void)
+{
+ return pci_alloc_dev(NULL);
+}
EXPORT_SYMBOL(alloc_pci_dev);
bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
@@ -1263,11 +1297,10 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
return NULL;
- dev = alloc_pci_dev();
+ dev = pci_alloc_dev(bus);
if (!dev)
return NULL;
- dev->bus = bus;
dev->devfn = devfn;
dev->vendor = l & 0xffff;
dev->device = (l >> 16) & 0xffff;
@@ -1275,6 +1308,7 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
pci_set_of_node(dev);
if (pci_setup_device(dev)) {
+ pci_bus_put(dev->bus);
kfree(dev);
return NULL;
}
@@ -1462,24 +1496,23 @@ static int pcie_find_smpss(struct pci_dev *dev, void *data)
if (!pci_is_pcie(dev))
return 0;
- /* For PCIE hotplug enabled slots not connected directly to a
- * PCI-E root port, there can be problems when hotplugging
- * devices. This is due to the possibility of hotplugging a
- * device into the fabric with a smaller MPS that the devices
- * currently running have configured. Modifying the MPS on the
- * running devices could cause a fatal bus error due to an
- * incoming frame being larger than the newly configured MPS.
- * To work around this, the MPS for the entire fabric must be
- * set to the minimum size. Any devices hotplugged into this
- * fabric will have the minimum MPS set. If the PCI hotplug
- * slot is directly connected to the root port and there are not
- * other devices on the fabric (which seems to be the most
- * common case), then this is not an issue and MPS discovery
- * will occur as normal.
+ /*
+ * We don't have a way to change MPS settings on devices that have
+ * drivers attached. A hot-added device might support only the minimum
+ * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
+ * where devices may be hot-added, we limit the fabric MPS to 128 so
+ * hot-added devices will work correctly.
+ *
+ * However, if we hot-add a device to a slot directly below a Root
+ * Port, it's impossible for there to be other existing devices below
+ * the port. We don't limit the MPS in this case because we can
+ * reconfigure MPS on both the Root Port and the hot-added device,
+ * and there are no other devices involved.
+ *
+ * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
*/
- if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
- (dev->bus->self &&
- pci_pcie_type(dev->bus->self) != PCI_EXP_TYPE_ROOT_PORT)))
+ if (dev->is_hotplug_bridge &&
+ pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
*smpss = 0;
if (*smpss > dev->pcie_mpss)
@@ -1554,6 +1587,22 @@ static void pcie_write_mrrs(struct pci_dev *dev)
"with pci=pcie_bus_safe.\n");
}
+static void pcie_bus_detect_mps(struct pci_dev *dev)
+{
+ struct pci_dev *bridge = dev->bus->self;
+ int mps, p_mps;
+
+ if (!bridge)
+ return;
+
+ mps = pcie_get_mps(dev);
+ p_mps = pcie_get_mps(bridge);
+
+ if (mps != p_mps)
+ dev_warn(&dev->dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
+ mps, pci_name(bridge), p_mps);
+}
+
static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
{
int mps, orig_mps;
@@ -1561,13 +1610,18 @@ static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
if (!pci_is_pcie(dev))
return 0;
+ if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
+ pcie_bus_detect_mps(dev);
+ return 0;
+ }
+
mps = 128 << *(u8 *)data;
orig_mps = pcie_get_mps(dev);
pcie_write_mps(dev, mps);
pcie_write_mrrs(dev);
- dev_info(&dev->dev, "PCI-E Max Payload Size set to %4d/%4d (was %4d), "
+ dev_info(&dev->dev, "Max Payload Size set to %4d/%4d (was %4d), "
"Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
orig_mps, pcie_get_readrq(dev));
@@ -1578,25 +1632,25 @@ static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
* parents then children fashion. If this changes, then this code will not
* work as designed.
*/
-void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
+void pcie_bus_configure_settings(struct pci_bus *bus)
{
u8 smpss;
- if (!pci_is_pcie(bus->self))
+ if (!bus->self)
return;
- if (pcie_bus_config == PCIE_BUS_TUNE_OFF)
+ if (!pci_is_pcie(bus->self))
return;
/* FIXME - Peer to peer DMA is possible, though the endpoint would need
- * to be aware to the MPS of the destination. To work around this,
+ * to be aware of the MPS of the destination. To work around this,
* simply force the MPS of the entire system to the smallest possible.
*/
if (pcie_bus_config == PCIE_BUS_PEER2PEER)
smpss = 0;
if (pcie_bus_config == PCIE_BUS_SAFE) {
- smpss = mpss;
+ smpss = bus->self->pcie_mpss;
pcie_find_smpss(bus->self, &smpss);
pci_walk_bus(bus, pcie_find_smpss, &smpss);
@@ -1700,15 +1754,19 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
goto err_out;
bridge->dev.parent = parent;
- bridge->dev.release = pci_release_bus_bridge_dev;
+ bridge->dev.release = pci_release_host_bridge_dev;
dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
error = pcibios_root_bridge_prepare(bridge);
- if (error)
- goto bridge_dev_reg_err;
+ if (error) {
+ kfree(bridge);
+ goto err_out;
+ }
error = device_register(&bridge->dev);
- if (error)
- goto bridge_dev_reg_err;
+ if (error) {
+ put_device(&bridge->dev);
+ goto err_out;
+ }
b->bridge = get_device(&bridge->dev);
device_enable_async_suspend(b->bridge);
pci_set_bus_of_node(b);
@@ -1764,8 +1822,6 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
class_dev_reg_err:
put_device(&bridge->dev);
device_unregister(&bridge->dev);
-bridge_dev_reg_err:
- kfree(bridge);
err_out:
kfree(b);
return NULL;
@@ -1948,7 +2004,6 @@ unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
max = pci_scan_child_bus(bus);
pci_assign_unassigned_bus_resources(bus);
- pci_enable_bridges(bus);
pci_bus_add_devices(bus);
return max;