This is a note to let you know that I've just added the patch titled
PCI: endpoint: Assign PCI domain number for endpoint controllers
to the 6.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-endpoint-assign-pci-domain-number-for-endpoint-c.patch
and it can be found in the queue-6.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b7776b2a5f62e73d68292576f25eebdfd648622d
Author: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Date: Wed Aug 28 21:16:15 2024 +0530
PCI: endpoint: Assign PCI domain number for endpoint controllers
[ Upstream commit 0328947c50324cf4b2d8b181bf948edb8101f59f ]
Right now, PCI endpoint subsystem doesn't assign PCI domain number for the
PCI endpoint controllers. But this domain number could be useful to the EPC
drivers to uniquely identify each controller based on the hardware instance
when there are multiple ones present in an SoC (even multiple RC/EP).
So let's make use of the existing pci_bus_find_domain_nr() API to allocate
domain numbers based on either devicetree (linux,pci-domain) property or
dynamic domain number allocation scheme.
It should be noted that the domain number allocated by this API will be
based on both RC and EP controllers in a SoC. If the 'linux,pci-domain' DT
property is present, then the domain number represents the actual hardware
instance of the PCI endpoint controller. If not, then the domain number
will be allocated based on the PCI EP/RC controller probe order.
If the architecture doesn't support CONFIG_PCI_DOMAINS_GENERIC (rare), then
currently a warning is thrown to indicate that the architecture specific
implementation is needed.
Link: https://lore.kernel.org/linux-pci/20240828-pci-qcom-hotplug-v4-5-263a385fbbcb@xxxxxxxxxx
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@xxxxxxxxxx>
Reviewed-by: Frank Li <Frank.Li@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index 84309dfe0c684..085a2de8b923d 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -838,6 +838,10 @@ void pci_epc_destroy(struct pci_epc *epc)
{
pci_ep_cfs_remove_epc_group(epc->group);
device_unregister(&epc->dev);
+
+#ifdef CONFIG_PCI_DOMAINS_GENERIC
+ pci_bus_release_domain_nr(NULL, &epc->dev);
+#endif
}
EXPORT_SYMBOL_GPL(pci_epc_destroy);
@@ -900,6 +904,16 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
epc->dev.release = pci_epc_release;
epc->ops = ops;
+#ifdef CONFIG_PCI_DOMAINS_GENERIC
+ epc->domain_nr = pci_bus_find_domain_nr(NULL, dev);
+#else
+ /*
+ * TODO: If the architecture doesn't support generic PCI
+ * domains, then a custom implementation has to be used.
+ */
+ WARN_ONCE(1, "This architecture doesn't support generic PCI domains\n");
+#endif
+
ret = dev_set_name(&epc->dev, "%s", dev_name(dev));
if (ret)
goto put_dev;
diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index 85bdf2adb7607..8e3dcac55dcd5 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -128,6 +128,7 @@ struct pci_epc_mem {
* @group: configfs group representing the PCI EPC device
* @lock: mutex to protect pci_epc ops
* @function_num_map: bitmap to manage physical function number
+ * @domain_nr: PCI domain number of the endpoint controller
* @init_complete: flag to indicate whether the EPC initialization is complete
* or not
*/
@@ -145,6 +146,7 @@ struct pci_epc {
/* mutex to protect against concurrent access of EP controller */
struct mutex lock;
unsigned long function_num_map;
+ int domain_nr;
bool init_complete;
};
