Hi, Bjorn: On Mon, Nov 25, 2013 at 09:17:11PM -0700, Bjorn Helgaas wrote: > On Mon, Nov 25, 2013 at 6:28 PM, Yinghai Lu <ying...@kernel.org> wrote: > > When one of children resources does not support MEM_64, MEM_64 for > > bridge get reset, so pull down whole pref resource on the bridge under 4G. > > > > If the bridge support pref mem 64, will only allocate that with pref mem64 > > to > > children that support it. > > For children resources if they only support pref mem 32, will allocate them > > from non pref mem instead. > > > > If the bridge only support 32bit pref mmio, will still have all children > > pref > > mmio under that. > > I can't figure out if this is supposed to fix a problem, and if so, > what problem it is. Can you include a URL for a bugzilla or other > problem description? >
This is intended to fix resource allocation problem when we expose 64-bit MMIO window in PowerNV platform. Please see issue 3 in: http://www.spinics.net/lists/linux-pci/msg26472.html Without this, any 32-bit prefetchable BARs will pull down the prefetahable window to allocate resource from 32-bit non-prefetchable range, preventing 64-bit MMIO from being used at all. What's worse, in some machines, 32-bit range is too small to provide fall back space for prefetchable window, causing all prefetchable BAR failing to get address. 64-bit MMIO on PowerNV is still pending (but definitely in plan). So if no one else complained, it seems not fix any problems in upstream. Thanks, Guo Chao > > -v2: Add release bridge res support with bridge mem res for pref_mem > > children res. > > -v3: refresh and make it can be applied early before for_each_dev_res > > patchset. > > > > Signed-off-by: Yinghai Lu <ying...@kernel.org> > > Tested-by: Guo Chao <y...@linux.vnet.ibm.com> > > --- > > drivers/pci/setup-bus.c | 133 > > ++++++++++++++++++++++++++++++++---------------- > > drivers/pci/setup-res.c | 14 ++++- > > 2 files changed, 101 insertions(+), 46 deletions(-) > > > > diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c > > index 219a410..b98419e 100644 > > --- a/drivers/pci/setup-bus.c > > +++ b/drivers/pci/setup-bus.c > > @@ -711,12 +711,11 @@ static void pci_bridge_check_ranges(struct pci_bus > > *bus) > > bus resource of a given type. Note: we intentionally skip > > the bus resources which have already been assigned (that is, > > have non-NULL parent resource). */ > > -static struct resource *find_free_bus_resource(struct pci_bus *bus, > > unsigned long type) > > +static struct resource *find_free_bus_resource(struct pci_bus *bus, > > + unsigned long type_mask, unsigned long type) > > { > > int i; > > struct resource *r; > > - unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM | > > - IORESOURCE_PREFETCH; > > > > pci_bus_for_each_resource(bus, r, i) { > > if (r == &ioport_resource || r == &iomem_resource) > > @@ -813,7 +812,8 @@ static void pbus_size_io(struct pci_bus *bus, > > resource_size_t min_size, > > resource_size_t add_size, struct list_head *realloc_head) > > { > > struct pci_dev *dev; > > - struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO); > > + struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO, > > + IORESOURCE_IO); > > resource_size_t size = 0, size0 = 0, size1 = 0; > > resource_size_t children_add_size = 0; > > resource_size_t min_align, align; > > @@ -913,15 +913,16 @@ static inline resource_size_t > > calculate_mem_align(resource_size_t *aligns, > > * guarantees that all child resources fit in this size. > > */ > > static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, > > - unsigned long type, resource_size_t min_size, > > - resource_size_t add_size, > > - struct list_head *realloc_head) > > + unsigned long type, unsigned long type2, > > + resource_size_t min_size, resource_size_t add_size, > > + struct list_head *realloc_head) > > { > > struct pci_dev *dev; > > resource_size_t min_align, align, size, size0, size1; > > resource_size_t aligns[12]; /* Alignments from 1Mb to 2Gb */ > > int order, max_order; > > - struct resource *b_res = find_free_bus_resource(bus, type); > > + struct resource *b_res = find_free_bus_resource(bus, > > + mask | IORESOURCE_PREFETCH, type); > > unsigned int mem64_mask = 0; > > resource_size_t children_add_size = 0; > > > > @@ -942,7 +943,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned > > long mask, > > struct resource *r = &dev->resource[i]; > > resource_size_t r_size; > > > > - if (r->parent || (r->flags & mask) != type) > > + if (r->parent || ((r->flags & mask) != type && > > + (r->flags & mask) != type2)) > > continue; > > r_size = resource_size(r); > > #ifdef CONFIG_PCI_IOV > > @@ -1115,8 +1117,9 @@ void __ref __pci_bus_size_bridges(struct pci_bus *bus, > > struct list_head *realloc_head) > > { > > struct pci_dev *dev; > > - unsigned long mask, prefmask; > > + unsigned long mask, prefmask, type2 = 0; > > resource_size_t additional_mem_size = 0, additional_io_size = 0; > > + struct resource *b_res; > > > > list_for_each_entry(dev, &bus->devices, bus_list) { > > struct pci_bus *b = dev->subordinate; > > @@ -1161,15 +1164,31 @@ void __ref __pci_bus_size_bridges(struct pci_bus > > *bus, > > has already been allocated by arch code, try > > non-prefetchable range for both types of PCI memory > > resources. */ > > + b_res = &bus->self->resource[PCI_BRIDGE_RESOURCES]; > > mask = IORESOURCE_MEM; > > prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH; > > - if (pbus_size_mem(bus, prefmask, prefmask, > > + if (b_res[2].flags & IORESOURCE_MEM_64) { > > + prefmask |= IORESOURCE_MEM_64; > > + if (pbus_size_mem(bus, prefmask, prefmask, prefmask, > > realloc_head ? 0 : additional_mem_size, > > - additional_mem_size, realloc_head)) > > - mask = prefmask; /* Success, size non-prefetch > > only. */ > > - else > > - additional_mem_size += additional_mem_size; > > - pbus_size_mem(bus, mask, IORESOURCE_MEM, > > + additional_mem_size, realloc_head)) { > > + /* Success, size non-pref64 only. */ > > + mask = prefmask; > > + type2 = prefmask & > > ~IORESOURCE_MEM_64; > > + } > > + } > > + if (!type2) { > > + prefmask &= ~IORESOURCE_MEM_64; > > + if (pbus_size_mem(bus, prefmask, prefmask, prefmask, > > + realloc_head ? 0 : > > additional_mem_size, > > + additional_mem_size, > > realloc_head)) { > > + /* Success, size non-prefetch only. */ > > + mask = prefmask; > > + } else > > + additional_mem_size += additional_mem_size; > > + type2 = IORESOURCE_MEM; > > + } > > + pbus_size_mem(bus, mask, IORESOURCE_MEM, type2, > > realloc_head ? 0 : additional_mem_size, > > additional_mem_size, realloc_head); > > break; > > @@ -1255,42 +1274,66 @@ static void __ref > > __pci_bridge_assign_resources(const struct pci_dev *bridge, > > static void pci_bridge_release_resources(struct pci_bus *bus, > > unsigned long type) > > { > > - int idx; > > - bool changed = false; > > - struct pci_dev *dev; > > + struct pci_dev *dev = bus->self; > > struct resource *r; > > unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM | > > - IORESOURCE_PREFETCH; > > + IORESOURCE_PREFETCH | IORESOURCE_MEM_64; > > + unsigned old_flags = 0; > > + struct resource *b_res; > > + int idx = 1; > > > > - dev = bus->self; > > - for (idx = PCI_BRIDGE_RESOURCES; idx <= PCI_BRIDGE_RESOURCE_END; > > - idx++) { > > - r = &dev->resource[idx]; > > - if ((r->flags & type_mask) != type) > > - continue; > > - if (!r->parent) > > - continue; > > - /* > > - * if there are children under that, we should release them > > - * all > > - */ > > - release_child_resources(r); > > - if (!release_resource(r)) { > > - dev_printk(KERN_DEBUG, &dev->dev, > > - "resource %d %pR released\n", idx, r); > > - /* keep the old size */ > > - r->end = resource_size(r) - 1; > > - r->start = 0; > > - r->flags = 0; > > - changed = true; > > - } > > - } > > + b_res = &dev->resource[PCI_BRIDGE_RESOURCES]; > > + > > + /* > > + * 1. if there is io port assign fail, will release bridge > > + * io port. > > + * 2. if there is non pref mmio assign fail, release bridge > > + * nonpref mmio. > > + * 3. if there is 64bit pref mmio assign fail, and bridge pref > > + * is 64bit, release bridge pref mmio. > > + * 4. if there is pref mmio assign fail, and bridge pref is > > + * 32bit mmio, release bridge pref mmio > > + * 5. if there is pref mmio assign fail, and bridge pref is not > > + * assigned, release bridge nonpref mmio. > > + */ > > + if (type & IORESOURCE_IO) > > + idx = 0; > > + else if (!(type & IORESOURCE_PREFETCH)) > > + idx = 1; > > + else if ((type & IORESOURCE_MEM_64) && > > + (b_res[2].flags & IORESOURCE_MEM_64)) > > + idx = 2; > > + else if (!(b_res[2].flags & IORESOURCE_MEM_64) && > > + (b_res[2].flags & IORESOURCE_PREFETCH)) > > + idx = 2; > > + else > > + idx = 1; > > + > > + r = &b_res[idx]; > > + > > + if (!r->parent) > > + return; > > + > > + /* > > + * if there are children under that, we should release them > > + * all > > + */ > > + release_child_resources(r); > > + if (!release_resource(r)) { > > + type = old_flags = r->flags & type_mask; > > + dev_printk(KERN_DEBUG, &dev->dev, "resource %d %pR > > released\n", > > + PCI_BRIDGE_RESOURCES + idx, r); > > + /* keep the old size */ > > + r->end = resource_size(r) - 1; > > + r->start = 0; > > + r->flags = 0; > > > > - if (changed) { > > /* avoiding touch the one without PREF */ > > if (type & IORESOURCE_PREFETCH) > > type = IORESOURCE_PREFETCH; > > __pci_setup_bridge(bus, type); > > + /* for next child res under same bridge */ > > + r->flags = old_flags; > > } > > } > > > > @@ -1469,7 +1512,7 @@ void pci_assign_unassigned_root_bus_resources(struct > > pci_bus *bus) > > LIST_HEAD(fail_head); > > struct pci_dev_resource *fail_res; > > unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM | > > - IORESOURCE_PREFETCH; > > + IORESOURCE_PREFETCH | IORESOURCE_MEM_64; > > int pci_try_num = 1; > > enum enable_type enable_local; > > > > diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c > > index 83c4d3b..e968412 100644 > > --- a/drivers/pci/setup-res.c > > +++ b/drivers/pci/setup-res.c > > @@ -208,9 +208,21 @@ static int __pci_assign_resource(struct pci_bus *bus, > > struct pci_dev *dev, > > > > /* First, try exact prefetching match.. */ > > ret = pci_bus_alloc_resource(bus, res, size, align, min, > > - IORESOURCE_PREFETCH, > > + IORESOURCE_PREFETCH | > > IORESOURCE_MEM_64, > > pcibios_align_resource, dev); > > > > + if (ret < 0 && > > + (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64))) { > > + /* > > + * That failed. > > + * > > + * Try below 4g pref > > + */ > > + ret = pci_bus_alloc_resource(bus, res, size, align, min, > > + IORESOURCE_PREFETCH, > > + pcibios_align_resource, dev); > > + } > > + > > if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) { > > /* > > * That failed. > > -- > > 1.8.1.4 > > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
