On Wed, Jul 02, 2025 at 04:30:48PM +0530, Manivannan Sadhasivam wrote: > On Mon, Jun 09, 2025 at 12:34:13PM GMT, Frank Li wrote: > > 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. > > > > We don't define OF node for any function, so device_set_of_node_from_dev() > also > ends up reusing the EPC node. So how can you make use of it in multi EPF > setup?
In mfd devices, children devices reuse parent's of_node drivers/gpio/gpio-adp5585.c drivers/input/keyboard/adp5589-keys.c drivers/pwm/pwm-adp5585.c multi EPF should be similar to create multi children devices of mfd. > I don't understand. > > > 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. Only share the same of_node. Actually pci host bridge have similar situation, all pci ep devices reuse bridge's of node. framework use rid to distringuish it. EPF can use device::id to do similar things. Actually iommu face the similar problem. So far, there are not EP device enable iommu yet, because it needs special mapping. Prevously, I consider create dymatic of_node for each EPF and copy iommu/msi information to each children. But when I see adp5585 case, I think direct use parent's of_node should be simple and good enough. In future, I suggest add children dt binding for it. For example: EPF provide a mailbox interface. how other dts node to refer to this mailbox's phandle? > > > > I don't know who you can provide *isolation* by reusing the EPC OF node. It is > same as using the EPC node directly. why it is same? Frank > > - Mani > > > Signed-off-by: Frank Li <frank...@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 577a9e490115c..95fb3d7c1d45e 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 749cee0bcf2cc..c0864935c6864 100644 > > --- a/include/linux/pci-epf.h > > +++ b/include/linux/pci-epf.h > > @@ -216,6 +216,8 @@ 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 > > > > > > -- > மணிவண்ணன் சதாசிவம்
