On Mon, Dec 22, 2014 at 05:53:55PM -0800, Yinghai Lu wrote: > On Fri, Dec 19, 2014 at 5:33 PM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote: > > On Fri, Dec 19, 2014 at 4:56 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > >> > >> Marek's case is a little easier because his system is using _CRS. We > >> should be able to notice that the Root Port window overlaps the host > >> bridge window, but isn't contained by it. In that case, if we merely > >> trim the Root Port window so it fits, everything will just work. > > > > Ok, will check that Monday. > > Please check attached patch that clip bridge resource. > > Marek, can you give it a try on top of v3.18? > > Thanks > > Yinghai > Subject: [RFC PATCH] PCI, x86: clip firmware assigned pci bridges under hostbridge > > Some bios put range that is not fully coverred by root bus resources. > Try to clip them and update them in pci bridge bars. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491 > Reported-by: Marek Kordik <kordikmarek@xxxxxxxxx> > Fixes: 5b28541552ef ("PCI: Restrict 64-bit prefetchable bridge windows to 64-bit resources") > Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx> > > --- > arch/x86/pci/i386.c | 43 +++++++++++++++++++++++++++++++------------ > drivers/pci/host-bridge.c | 31 +++++++++++++++++++++++++++++++ > include/linux/pci.h | 2 ++ > 3 files changed, 64 insertions(+), 12 deletions(-) > > Index: linux-2.6/arch/x86/pci/i386.c > =================================================================== > --- linux-2.6.orig/arch/x86/pci/i386.c > +++ linux-2.6/arch/x86/pci/i386.c > @@ -205,10 +205,11 @@ EXPORT_SYMBOL(pcibios_align_resource); > * as well. > */ > > -static void pcibios_allocate_bridge_resources(struct pci_dev *dev) > +static bool pcibios_allocate_bridge_resources(struct pci_dev *dev) > { > int idx; > struct resource *r; > + bool changed = false; > > for (idx = PCI_BRIDGE_RESOURCES; idx < PCI_NUM_RESOURCES; idx++) { > r = &dev->resource[idx]; > @@ -216,17 +217,31 @@ static void pcibios_allocate_bridge_reso > continue; > if (r->parent) /* Already allocated */ > continue; > - if (!r->start || pci_claim_resource(dev, idx) < 0) { > - /* > - * Something is wrong with the region. > - * Invalidate the resource to prevent > - * child resource allocations in this > - * range. > - */ > - r->start = r->end = 0; > - r->flags = 0; > + if (!r->start) > + goto clear; > + if (pci_claim_resource(dev, idx) < 0) { > + /* try again after clip for pci bridge*/ > + if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI && > + pcibios_resource_clip_in_host_bridge(dev->bus, r)) { Can you do this so it clips to any upstream bridge, whether it's a host bridge or a PCI-to-PCI bridge? It doesn't seem like this has to be specific to host bridge windows -- any device below a PCI-to-PCI bridge has to use address space forwarded by that upstream bridge. I wish this were in generic code. There's nothing architecture-specific about the problem, but this patch only fixes things on x86. Can you make a similar change in the corresponding code for other arches, as well? > + changed = true; > + if (pci_claim_resource(dev, idx) >= 0) > + continue; > + } > + goto clear; > } > + continue; > +clear: > + /* > + * Something is wrong with the region. > + * Invalidate the resource to prevent > + * child resource allocations in this > + * range. > + */ > + r->start = r->end = 0; > + r->flags = 0; > } > + > + return changed; > } > > static void pcibios_allocate_bus_resources(struct pci_bus *bus) > @@ -234,8 +249,12 @@ static void pcibios_allocate_bus_resourc > struct pci_bus *child; > > /* Depth-First Search on bus tree */ > - if (bus->self) > - pcibios_allocate_bridge_resources(bus->self); > + if (bus->self) { > + bool changed = pcibios_allocate_bridge_resources(bus->self); > + > + if (changed) > + pci_setup_bridge(bus); > + } > list_for_each_entry(child, &bus->children, node) > pcibios_allocate_bus_resources(child); > } > Index: linux-2.6/drivers/pci/host-bridge.c > =================================================================== > --- linux-2.6.orig/drivers/pci/host-bridge.c > +++ linux-2.6/drivers/pci/host-bridge.c > @@ -31,6 +31,37 @@ void pci_set_host_bridge_release(struct > bridge->release_data = release_data; > } > > +bool pcibios_resource_clip_in_host_bridge(struct pci_bus *bus, > + struct resource *res) > +{ > + struct pci_host_bridge *bridge = find_pci_host_bridge(bus); > + struct pci_host_bridge_window *window; > + resource_size_t start, end; > + > + list_for_each_entry(window, &bridge->windows, list) { > + if (resource_type(res) != resource_type(window->res)) > + continue; > + > + start = max(window->res->start, res->start); > + end = min(window->res->end, res->end); > + > + /* no overlap ? */ > + if (start > end) > + continue; > + > + if (res->start == start && res->end == end) > + return false; > + > + /* changed */ > + res->start = start; > + res->end = end; I think it'd be useful to emit a diagnostic here so there's a clue in dmesg about what's going on. > + return true; > + } > + > + return false; > +} > + > void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region, > struct resource *res) > { > Index: linux-2.6/include/linux/pci.h > =================================================================== > --- linux-2.6.orig/include/linux/pci.h > +++ linux-2.6/include/linux/pci.h > @@ -762,6 +762,8 @@ void pci_fixup_cardbus(struct pci_bus *) > > /* Generic PCI functions used internally */ > > +bool pcibios_resource_clip_in_host_bridge(struct pci_bus *bus, > + struct resource *res); > void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region, > struct resource *res); > void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res, -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
