Hi Simon, On Sun, Aug 23, 2015 at 5:58 AM, Simon Glass <s...@chromium.org> wrote: > At present, until a PCI bus is probed, it cannot be found by its sequence > number unless it has an alias. This is the same with any device. > > However with PCI this is more annoying than usual, since bus 0 is always the > same device. > > Add a function that tries a little harder to locate PCI bus 0. This means > that PCI enumeration will happen automatically on the first access. > > Signed-off-by: Simon Glass <s...@chromium.org> > --- > > Changes in v2: > - Adjust pci_get_bus() to probe bus 0 so that the required bus is found > > drivers/pci/pci-uclass.c | 23 ++++++++++++++++++++--- > 1 file changed, 20 insertions(+), 3 deletions(-) > > diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c > index c90e7ac..ca47dc3 100644 > --- a/drivers/pci/pci-uclass.c > +++ b/drivers/pci/pci-uclass.c > @@ -20,6 +20,23 @@ > > DECLARE_GLOBAL_DATA_PTR; > > +static int pci_get_bus(int busnum, struct udevice **busp) > +{ > + int ret; > + > + ret = uclass_get_device_by_seq(UCLASS_PCI, busnum, busp); > + > + /* Since buses may not be numbered yet try a little harder with bus 0 > */ > + if (ret == -ENODEV) { > + ret = uclass_first_device(UCLASS_PCI, busp); > + if (!ret)
By looking at the API comments of uclass_first_device(), I think this logic should be: if (ret || ((!ret) && (!*busp))) > + return -ENODEV; > + ret = uclass_get_device_by_seq(UCLASS_PCI, busnum, busp); > + } > + > + return ret; > +} > + > struct pci_controller *pci_bus_to_hose(int busnum) > { > struct udevice *bus; > @@ -128,7 +145,7 @@ int pci_bus_find_bdf(pci_dev_t bdf, struct udevice **devp) > struct udevice *bus; > int ret; > > - ret = uclass_get_device_by_seq(UCLASS_PCI, PCI_BUS(bdf), &bus); > + ret = pci_get_bus(PCI_BUS(bdf), &bus); > if (ret) > return ret; > return pci_bus_find_devfn(bus, PCI_MASK_BUS(bdf), devp); > @@ -206,7 +223,7 @@ int pci_write_config(pci_dev_t bdf, int offset, unsigned > long value, > struct udevice *bus; > int ret; > > - ret = uclass_get_device_by_seq(UCLASS_PCI, PCI_BUS(bdf), &bus); > + ret = pci_get_bus(PCI_BUS(bdf), &bus); > if (ret) > return ret; > > @@ -271,7 +288,7 @@ int pci_read_config(pci_dev_t bdf, int offset, unsigned > long *valuep, > struct udevice *bus; > int ret; > > - ret = uclass_get_device_by_seq(UCLASS_PCI, PCI_BUS(bdf), &bus); > + ret = pci_get_bus(PCI_BUS(bdf), &bus); > if (ret) > return ret; > > -- I think we need also update pci_bus_to_hose() to use pci_get_bus() instead of calling uclass_get_device_by_seq(). Regards, Bin _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot