[PATCH 1/4] PCI: honor child buses add_size in hot plug configuration

From: Ram Pai
Date: Mon Jun 20 2011 - 18:47:49 EST


From: Yinghai Lu <yinghai@xxxxxxxxxx>

Recent pci_bus_size change will use add_size for minimum resource size for pcie
hotplug bridge. But it does not pass children back to parent bridge.

that will have problem on some setup like:
hot add one chassis with more hot plug slots.
for example: if the chassis have 8 slots, we should allocate 8x2M instead
of one 1x2M for parent bus.

So try to get child add_size and compare the sum with parent bus bridge...

Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
Reviewed-by: Ram Pai <linuxram@xxxxxxxxxx>
---
drivers/pci/setup-bus.c | 26 ++++++++++++++++++++++++++
1 files changed, 26 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 1e9e5a5..e42b89a 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -536,6 +536,20 @@ static resource_size_t calculate_memsize(resource_size_t size,
return size;
}

+static resource_size_t get_res_add_size(struct resource_list_x *add_head,
+ struct resource *res)
+{
+ struct resource_list_x *list;
+
+ /* check if it is in add_head list */
+ for (list = add_head->next; list && list->res != res;
+ list = list->next);
+ if (list)
+ return list->add_size;
+
+ return 0;
+}
+
/**
* pbus_size_io() - size the io window of a given bus
*
@@ -555,6 +569,7 @@ 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);
unsigned long size = 0, size0 = 0, size1 = 0;
+ resource_size_t children_add_size = 0;

if (!b_res)
return;
@@ -575,10 +590,15 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
size += r_size;
else
size1 += r_size;
+
+ if (add_head)
+ children_add_size += get_res_add_size(add_head, r);
}
}
size0 = calculate_iosize(size, min_size, size1,
resource_size(b_res), 4096);
+ if (children_add_size > add_size)
+ add_size = children_add_size;
size1 = (!add_head || (add_head && !add_size)) ? size0 :
calculate_iosize(size, min_size+add_size, size1,
resource_size(b_res), 4096);
@@ -620,6 +640,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
int order, max_order;
struct resource *b_res = find_free_bus_resource(bus, type);
unsigned int mem64_mask = 0;
+ resource_size_t children_add_size = 0;

if (!b_res)
return 0;
@@ -661,6 +682,9 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
if (order > max_order)
max_order = order;
mem64_mask &= r->flags & IORESOURCE_MEM_64;
+
+ if (add_head)
+ children_add_size += get_res_add_size(add_head, r);
}
}
align = 0;
@@ -677,6 +701,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
align += aligns[order];
}
size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align);
+ if (children_add_size > add_size)
+ add_size = children_add_size;
size1 = (!add_head || (add_head && !add_size)) ? size0 :
calculate_memsize(size, min_size+add_size, 0,
resource_size(b_res), min_align);
--
1.7.0.4

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