diff options
Diffstat (limited to 'drivers/pci/controller/dwc')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-designware-ep.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index bad588ef69a41..44a617d54b15f 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -222,8 +222,28 @@ static int dw_pcie_ep_set_bar(struct pci_epc *epc, u8 func_no, u8 vfunc_no, if ((flags & PCI_BASE_ADDRESS_MEM_TYPE_64) && (bar & 1)) return -EINVAL; - if (ep->epf_bar[bar]) + /* + * Certain EPF drivers dynamically change the physical address of a BAR + * (i.e. they call set_bar() twice, without ever calling clear_bar(), as + * calling clear_bar() would clear the BAR's PCI address assigned by the + * host). + */ + if (ep->epf_bar[bar]) { + /* + * We can only dynamically change a BAR if the new BAR size and + * BAR flags do not differ from the existing configuration. + */ + if (ep->epf_bar[bar]->barno != bar || + ep->epf_bar[bar]->size != size || + ep->epf_bar[bar]->flags != flags) + return -EINVAL; + + /* + * When dynamically changing a BAR, skip writing the BAR reg, as + * that would clear the BAR's PCI address assigned by the host. + */ goto config_atu; + } reg = PCI_BASE_ADDRESS_0 + (4 * bar); |