For every (IO, MEM, MEM64) bridge window, count the fixed resources of
its children endpoints and children bridge windows:
| <- BAR -> | | <- child bus fixed_range_hard -> | | <- fixed BAR -> |
| <- bus's fixed_range_hard -> |
| <- bus's bridge window -> |
These ranges will be later used to arrange bridge windows in a way which
covers every immovable BAR as well as the movable ones during hotplug.
Signed-off-by: Sergey Miroshnichenko <s.miroshnichenko@xxxxxxxxx>
---
drivers/pci/pci.h | 14 +++++++
drivers/pci/probe.c | 82 +++++++++++++++++++++++++++++++++++++++++
drivers/pci/setup-bus.c | 17 +++++++++
include/linux/pci.h | 6 +++
4 files changed, 119 insertions(+)
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 56b905068ac5..14e3ebe68010 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -364,6 +364,20 @@ static inline bool pci_dev_is_disconnected(const struct pci_dev *dev)
return dev->error_state == pci_channel_io_perm_failure;
}
+static inline int pci_get_bridge_resource_idx(struct resource *r)
+{
+ int idx = 1;
+
+ if (r->flags & IORESOURCE_IO)
+ idx = 0;
+ else if (!(r->flags & IORESOURCE_PREFETCH))
+ idx = 1;
+ else if (r->flags & IORESOURCE_MEM_64)
+ idx = 2;
+
+ return idx;
+}
+
/* pci_dev priv_flags */
#define PCI_DEV_ADDED 0
#define PCI_DEV_IGNORE 1
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index c1d88721697e..cc302a5798bf 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -500,6 +500,7 @@ void pci_read_bridge_bases(struct pci_bus *child)
static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
{
struct pci_bus *b;
+ int idx;
b = kzalloc(sizeof(*b), GFP_KERNEL);
if (!b)
@@ -516,6 +517,11 @@ static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
if (parent)
b->domain_nr = parent->domain_nr;
#endif
+ for (idx = 0; idx < PCI_BRIDGE_RESOURCE_NUM; ++idx) {
+ b->fixed_range_hard[idx].start = (resource_size_t)-1;
+ b->fixed_range_hard[idx].end = 0;
+ }
+
return b;
}
@@ -3261,6 +3267,81 @@ static void pci_setup_bridges(struct pci_bus *bus)
pci_setup_bridge(bus);
}
+static void pci_bus_update_fixed_range_hard(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+ int idx;
+ resource_size_t start, end;
+
+ for (idx = 0; idx < PCI_BRIDGE_RESOURCE_NUM; ++idx) {
+ bus->fixed_range_hard[idx].start = (resource_size_t)-1;
+ bus->fixed_range_hard[idx].end = 0;
+ }
+
+ list_for_each_entry(dev, &bus->devices, bus_list)
+ if (dev->subordinate)
+ pci_bus_update_fixed_range_hard(dev->subordinate);
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ int i;
+
+ for (i = 0; i < PCI_BRIDGE_RESOURCES; ++i) {
+ struct resource *r = &dev->resource[i];
+
+ if (!r->flags || (r->flags & IORESOURCE_UNSET) || !r->parent)
+ continue;
+
+ if (r->flags & IORESOURCE_PCI_FIXED) {
+ idx = pci_get_bridge_resource_idx(r);
+ start = bus->fixed_range_hard[idx].start;
+ end = bus->fixed_range_hard[idx].end;
+
+ if (start > r->start)
+ start = r->start;
+ if (end < r->end)
+ end = r->end;
+
+ if (bus->fixed_range_hard[idx].start != start ||
+ bus->fixed_range_hard[idx].end != end) {
+ dev_dbg(&bus->dev, "%s: Found fixed 0x%llx-0x%llx in %s, expand the fixed bridge window %d to 0x%llx-0x%llx\n",
+ __func__,
+ (unsigned long long)r->start,
+ (unsigned long long)r->end,
+ dev_name(&dev->dev), idx,
+ (unsigned long long)start,
+ (unsigned long long)end);
+ bus->fixed_range_hard[idx].start = start;
+ bus->fixed_range_hard[idx].end = end;
+ }
+ }
+ }
+
+ if (dev->subordinate) {
+ struct pci_bus *child = dev->subordinate;
+
+ for (idx = 0; idx < PCI_BRIDGE_RESOURCE_NUM; ++idx) {
+ start = bus->fixed_range_hard[idx].start;
+ end = bus->fixed_range_hard[idx].end;
+
+ if (start > child->fixed_range_hard[idx].start)
+ start = child->fixed_range_hard[idx].start;
+ if (end < child->fixed_range_hard[idx].end)
+ end = child->fixed_range_hard[idx].end;
+
+ if (start < bus->fixed_range_hard[idx].start ||
+ end > bus->fixed_range_hard[idx].end) {
+ dev_dbg(&bus->dev, "%s: Expand the fixed bridge window %d from %s to 0x%llx-0x%llx\n",
+ __func__, idx, dev_name(&child->dev),
+ (unsigned long long)start,
+ (unsigned long long)end);
+ bus->fixed_range_hard[idx].start = start;
+ bus->fixed_range_hard[idx].end = end;
+ }
+ }
+ }
+ }
+}
+
static struct pci_dev *pci_find_next_new_device(struct pci_bus *bus)
{
struct pci_dev *dev;
@@ -3361,6 +3442,7 @@ unsigned int pci_rescan_bus(struct pci_bus *bus)
pci_bus_rescan_prepare(root);
max = pci_scan_child_bus(root);
+ pci_bus_update_fixed_range_hard(root);
pci_reassign_root_bus_resources(root);
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index a1b1b1cda3e8..59af85029869 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -916,9 +916,17 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
resource_size_t children_add_size = 0;
resource_size_t min_align, align;
+ resource_size_t fixed_start = bus->fixed_range_hard[0].start;
+ resource_size_t fixed_end = bus->fixed_range_hard[0].end;
+ resource_size_t fixed_size = (fixed_start < fixed_end) ?
+ (fixed_end - fixed_start + 1) : 0;
+
if (!b_res)
return;
+ if (min_size < fixed_size)
+ min_size = fixed_size;
+
min_align = window_alignment(bus, IORESOURCE_IO);
list_for_each_entry(dev, &bus->devices, bus_list) {
int i;
@@ -1027,6 +1035,15 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
resource_size_t children_add_size = 0;
resource_size_t children_add_align = 0;
resource_size_t add_align = 0;
+ bool is_mem64 = (mask & IORESOURCE_MEM_64);
+
+ resource_size_t fixed_start = bus->fixed_range_hard[is_mem64 ? 2 : 1].start;
+ resource_size_t fixed_end = bus->fixed_range_hard[is_mem64 ? 2 : 1].end;
+ resource_size_t fixed_size = (fixed_start < fixed_end) ?
+ (fixed_end - fixed_start + 1) : 0;
+
+ if (min_size < fixed_size)
+ min_size = fixed_size;
if (!b_res)
return -ENOSPC;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 5c739bf0c94f..e2b4742c477a 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -569,6 +569,12 @@ struct pci_bus {
struct list_head resources; /* Address space routed to this bus */
struct resource busn_res; /* Bus numbers routed to this bus */
+ /*
+ * If there are fixed resources in the bridge window, the hard range
+ * contains the lowest and the highest addresses of them.
+ */
+ struct resource fixed_range_hard[PCI_BRIDGE_RESOURCE_NUM];
+
struct pci_ops *ops; /* Configuration access functions */
struct msi_controller *msi; /* MSI controller */
void *sysdata; /* Hook for sys-specific extension */
--
2.20.1
