PCI: pcie: Ensure hotplug ports have a minimum number of resources
In general a BIOS may goof or we may hotplug in a hotplug controller.
In either case the kernel needs to reserve resources for plugging
in more devices in the future instead of creating a minimal resource
assignment.
We already do this for cardbus bridges I am just adding a variant
for pcie bridges.
v2: Make testing for pcie hotplug bridges based on a flag.
So far we only set the flag for pcie but a header_quirk
could easily be added for the non-standard pci hotplug
bridges.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 7c443b4..cb1a027 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -309,7 +309,7 @@
since these windows have 4K granularity and the IO ranges
of non-bridge PCI devices are limited to 256 bytes.
We must be careful with the ISA aliasing though. */
-static void pbus_size_io(struct pci_bus *bus)
+static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size)
{
struct pci_dev *dev;
struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
@@ -336,6 +336,8 @@
size1 += r_size;
}
}
+ if (size < min_size)
+ size = min_size;
/* To be fixed in 2.5: we should have sort of HAVE_ISA
flag in the struct pci_bus. */
#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
@@ -354,7 +356,8 @@
/* Calculate the size of the bus and minimal alignment which
guarantees that all child resources fit in this size. */
-static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type)
+static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
+ unsigned long type, resource_size_t min_size)
{
struct pci_dev *dev;
resource_size_t min_align, align, size;
@@ -404,6 +407,8 @@
mem64_mask &= r->flags & IORESOURCE_MEM_64;
}
}
+ if (size < min_size)
+ size = min_size;
align = 0;
min_align = 0;
@@ -483,6 +488,7 @@
{
struct pci_dev *dev;
unsigned long mask, prefmask;
+ resource_size_t min_mem_size = 0, min_io_size = 0;
list_for_each_entry(dev, &bus->devices, bus_list) {
struct pci_bus *b = dev->subordinate;
@@ -512,8 +518,12 @@
case PCI_CLASS_BRIDGE_PCI:
pci_bridge_check_ranges(bus);
+ if (bus->self->is_hotplug_bridge) {
+ min_io_size = pci_hotplug_io_size;
+ min_mem_size = pci_hotplug_mem_size;
+ }
default:
- pbus_size_io(bus);
+ pbus_size_io(bus, min_io_size);
/* If the bridge supports prefetchable range, size it
separately. If it doesn't, or its prefetchable window
has already been allocated by arch code, try
@@ -521,9 +531,11 @@
resources. */
mask = IORESOURCE_MEM;
prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
- if (pbus_size_mem(bus, prefmask, prefmask))
+ if (pbus_size_mem(bus, prefmask, prefmask, min_mem_size))
mask = prefmask; /* Success, size non-prefetch only. */
- pbus_size_mem(bus, mask, IORESOURCE_MEM);
+ else
+ min_mem_size += min_mem_size;
+ pbus_size_mem(bus, mask, IORESOURCE_MEM, min_mem_size);
break;
}
}