On Tue, Oct 10, 2023 at 09:29:13PM +0530, Manivannan Sadhasivam wrote: > This callback can be used by the platform drivers to do configuration once > all the devices are scanned. Like changing LNKCTL of all downstream devices > to enable ASPM etc... > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> > --- > drivers/pci/controller/dwc/pcie-designware-host.c | 3 +++ > drivers/pci/controller/dwc/pcie-designware.h | 1 + > 2 files changed, 4 insertions(+) > > diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c > index a7170fd0e847..7991f0e179b2 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-host.c > +++ b/drivers/pci/controller/dwc/pcie-designware-host.c > @@ -502,6 +502,9 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp) > if (ret) > goto err_stop_link; > > + if (pp->ops->host_post_init) > + pp->ops->host_post_init(pp); I know we talked about this a little bit in the context of enabling ASPM for devices below qcom 1.9.0 controllers at https://lore.kernel.org/r/20231011050058.GC3508@thinkpad But I didn't realize at the time that this callback adds a fundamental difference between devices present at boot-time (these devices can be affected by this callback) and any devices hot-added later (we never run this callback again, so anything done by .host_post_init() never applies to them). We merged this for now, and it helps enable ASPM for builtin devices on qcom, but I don't feel good about this from a larger DWC perspective. If other drivers use this and they support hot-add, I think we're going to have problems. > return 0; > > err_stop_link: > diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h > index ef0b2efa9f93..efb4d4754fc8 100644 > --- a/drivers/pci/controller/dwc/pcie-designware.h > +++ b/drivers/pci/controller/dwc/pcie-designware.h > @@ -301,6 +301,7 @@ enum dw_pcie_ltssm { > struct dw_pcie_host_ops { > int (*host_init)(struct dw_pcie_rp *pp); > void (*host_deinit)(struct dw_pcie_rp *pp); > + void (*host_post_init)(struct dw_pcie_rp *pp); > int (*msi_host_init)(struct dw_pcie_rp *pp); > void (*pme_turn_off)(struct dw_pcie_rp *pp); > }; > -- > 2.25.1 >
