Re: [PATCH v2 3/6] PCI: brcmstb: Add "refusal mode" to preclude PCIe-induced CPU aborts

[Bjorn Helgaas]

On Sat, Jul 16, 2022 at 06:24:50PM -0400, Jim Quinlan wrote:
> Our PCIe RC HW has an atypical behavior: if it does not have PCIe link
> established between itself and downstream, any subsequent config space
> access causes a CPU abort.  This commit sets a "refusal mode" if the PCIe
> link-up fails, and this has our pci_ops map_bus function returning a NULL
> address, which in turn precludes the access from happening.

> @@ -687,6 +688,19 @@ static void __iomem *brcm_pcie_map_conf(struct pci_bus *bus, unsigned int devfn,

Oh, and I forgot to mention that brcmstb is one of the few drivers
that doesn't name these functions ".*_map_bus()".  It's helpful when
they all match a simple grep pattern.  Maybe a patch at the end could
fix this.