| Message ID | 1410184472-17630-10-git-send-email-Liviu.Dudau@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On 9/8/2014 8:54 AM, Liviu Dudau wrote: > If the firmware has not assigned all the bus resources and > we are not just probing the PCIe busses, it makes sense to > assign the unassigned resources in pci_scan_root_bus(). > > Cc: Bjorn Helgaas <bhelgaas@google.com> > Cc: Arnd Bergmann <arnd@arndb.de> > Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> > Cc: Rob Herring <robh+dt@kernel.org> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> > --- > drivers/pci/probe.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > index ef891d2..508cf61 100644 > --- a/drivers/pci/probe.c > +++ b/drivers/pci/probe.c > @@ -1953,6 +1953,9 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus, > if (!found) > pci_bus_update_busn_res_end(b, max); > > + if (!pci_has_flag(PCI_PROBE_ONLY)) > + pci_assign_unassigned_bus_resources(b); > + > pci_bus_add_devices(b); > return b; > } > Liviu, Besides the check for PCI_PROBE_ONLY here, I think we also need to avoid calling "pci_enable_resources()" in the "driver/pci/pci.c: pcibios_enable_device()" for PCI_PROBE_ONLY mode since the resource is not assigned by Linux. Otherwise, the "drivers/pci/setup-res.c: pci_enable_resource()" would fail w/ error: can't enable device: BAR ..... not assigned Actually, in "arch/arm/kernel/bios32.c:", the weak "pcibios_enable_device()" function also has the check for PCI_PROBE_ONLY mode before calling pci_enable_resources(). Thanks, Suravee -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Sep 12, 2014 at 11:13:51AM +0100, Suravee Suthikulpanit wrote: > On 9/8/2014 8:54 AM, Liviu Dudau wrote: > > If the firmware has not assigned all the bus resources and > > we are not just probing the PCIe busses, it makes sense to > > assign the unassigned resources in pci_scan_root_bus(). > > > > Cc: Bjorn Helgaas <bhelgaas@google.com> > > Cc: Arnd Bergmann <arnd@arndb.de> > > Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> > > Cc: Rob Herring <robh+dt@kernel.org> > > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> > > --- > > drivers/pci/probe.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > > index ef891d2..508cf61 100644 > > --- a/drivers/pci/probe.c > > +++ b/drivers/pci/probe.c > > @@ -1953,6 +1953,9 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus, > > if (!found) > > pci_bus_update_busn_res_end(b, max); > > > > + if (!pci_has_flag(PCI_PROBE_ONLY)) > > + pci_assign_unassigned_bus_resources(b); > > + > > pci_bus_add_devices(b); > > return b; > > } > > > > Liviu, > > Besides the check for PCI_PROBE_ONLY here, I think we also need to avoid calling > "pci_enable_resources()" in the "driver/pci/pci.c: pcibios_enable_device()" for > PCI_PROBE_ONLY mode since the resource is not assigned by Linux. Otherwise, the > "drivers/pci/setup-res.c: pci_enable_resource()" would fail w/ error: > > can't enable device: BAR ..... not assigned Hmm, are you sure that is not because the host bridge resources have not been requested? pci-host-generic.c uses PCI_PROBE_ONLY and yet it works with the series as is. But it does request_resource() for the host bridge resources inside the driver. Best regards, Liviu > > Actually, in "arch/arm/kernel/bios32.c:", the weak "pcibios_enable_device()" function > also has the check for PCI_PROBE_ONLY mode before calling pci_enable_resources(). > > Thanks, > > Suravee > >
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index ef891d2..508cf61 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1953,6 +1953,9 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus, if (!found) pci_bus_update_busn_res_end(b, max); + if (!pci_has_flag(PCI_PROBE_ONLY)) + pci_assign_unassigned_bus_resources(b); + pci_bus_add_devices(b); return b; }
If the firmware has not assigned all the bus resources and we are not just probing the PCIe busses, it makes sense to assign the unassigned resources in pci_scan_root_bus(). Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Cc: Rob Herring <robh+dt@kernel.org> Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> --- drivers/pci/probe.c | 3 +++ 1 file changed, 3 insertions(+)