[PATCH AUTOSEL 6.1 43/60] PCI: Align extra resources for hotplug bridges properly

Sasha Levin
2023-03-03T21:47:44Z

From: Mika Westerberg <mika.westerberg@linux.intel.com>

[ Upstream commit 08f0a15ee8adb4846b08ca5d5c175fbf0f652bc9 ]

After division the extra resource space per hotplug bridge may not be
aligned according to the window alignment, so align it before passing it
down for further distribution.

Link: https://lore.kernel.org/r/20230131092405.29121-2-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/setup-bus.c | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index b4096598dbcbb..e440f264accb8 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1891,6 +1891,7 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus,
* resource space between hotplug bridges.
*/
for_each_pci_bridge(dev, bus) {
+ struct resource *res;
struct pci_bus *b;

b = dev->subordinate;
@@ -1902,16 +1903,28 @@ static void pci_bus_distribute_available_resources(struct pci_bus *bus,
* hotplug-capable downstream ports taking alignment into
* account.
*/
- io.end = io.start + io_per_hp - 1;
- mmio.end = mmio.start + mmio_per_hp - 1;
- mmio_pref.end = mmio_pref.start + mmio_pref_per_hp - 1;
+ res = &dev->resource[PCI_BRIDGE_IO_WINDOW];
+ align = pci_resource_alignment(dev, res);
+ io.end = align ? io.start + ALIGN_DOWN(io_per_hp, align) - 1
+ : io.start + io_per_hp - 1;
+
+ res = &dev->resource[PCI_BRIDGE_MEM_WINDOW];
+ align = pci_resource_alignment(dev, res);
+ mmio.end = align ? mmio.start + ALIGN_DOWN(mmio_per_hp, align) - 1
+ : mmio.start + mmio_per_hp - 1;
+
+ res = &dev->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
+ align = pci_resource_alignment(dev, res);
+ mmio_pref.end = align ? mmio_pref.start +
+ ALIGN_DOWN(mmio_pref_per_hp, align) - 1
+ : mmio_pref.start + mmio_pref_per_hp - 1;

pci_bus_distribute_available_resources(b, add_list, io, mmio,
mmio_pref);

- io.start += io_per_hp;
- mmio.start += mmio_per_hp;
- mmio_pref.start += mmio_pref_per_hp;
+ io.start += io.end + 1;
+ mmio.start += mmio.end + 1;
+ mmio_pref.start += mmio_pref.end + 1;
}
}

--
2.39.2