[PATCH v18 06/15] PCI: endpoint: Set ID and of_node for function driver

Frank Li
2025-04-14T18:31:52Z

Set device ID as 'vfunc_no << 3 | func_no' and use
'device_set_of_node_from_dev()' to set 'of_node' the same as the EPC parent
device.

Currently, EPF 'of_node' is NULL, but many functions depend on 'of_node'
settings, such as DMA, IOMMU, and MSI. At present, all DMA allocation
functions use the EPC's device node, but they should use the EPF one.
For multiple function drivers, IOMMU/MSI should be different for each
function driver.

If multiple function devices share the same EPC device, there will be
no isolation between them. Setting the ID and 'of_node' prepares for
proper support.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change from v14 to v16
- none

change from v13 to v14
new patch
---
drivers/pci/endpoint/pci-epf-core.c | 4 ++++
include/linux/pci-epf.h | 2 ++
2 files changed, 6 insertions(+)

diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
index 394395c7f8dec..d04224b8e1631 100644
--- a/drivers/pci/endpoint/pci-epf-core.c
+++ b/drivers/pci/endpoint/pci-epf-core.c
@@ -120,12 +120,16 @@ int pci_epf_bind(struct pci_epf *epf)
epf_vf->sec_epc_func_no = epf->sec_epc_func_no;
epf_vf->epc = epf->epc;
epf_vf->sec_epc = epf->sec_epc;
+ epf_vf->dev.id = PCI_EPF_DEVID(epf->func_no, vfunc_no);
+ device_set_of_node_from_dev(&epf_vf->dev, epc->dev.parent);
ret = epf_vf->driver->ops->bind(epf_vf);
if (ret)
goto ret;
epf_vf->is_bound = true;
}

+ epf->dev.id = PCI_EPF_DEVID(epf->func_no, 0);
+ device_set_of_node_from_dev(&epf->dev, epc->dev.parent);
ret = epf->driver->ops->bind(epf);
if (ret)
goto ret;
diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
index 879d19cebd4fc..1040d83740f9a 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h
@@ -213,6 +213,8 @@ static inline void *epf_get_drvdata(struct pci_epf *epf)
return dev_get_drvdata(&epf->dev);
}

+#define PCI_EPF_DEVID(func_no, vfunc_no) ((vfunc_no) << 3 | (func_no))
+
struct pci_epf *pci_epf_create(const char *name);
void pci_epf_destroy(struct pci_epf *epf);
int __pci_epf_register_driver(struct pci_epf_driver *driver,

--
2.34.1