On Mon, Feb 17, 2014 at 11:28 AM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote: > On Sun, Feb 16, 2014 at 8:50 PM, Guo Chao <yan@xxxxxxxxxxxxxxxxxx> wrote: >> pbus_size_mem() limits resource alignment within 2G. We want to extend >> this limit to support a 16G BAR. I found similar effort was tried before: >> >> https://lkml.org/lkml/2012/6/21/411 >> >> What's the result? Does anyone come up with an adaptive algorithm? > > I suggest following changes: > > From: Nikhil P Rao <nikhil.rao@xxxxxxxxx> > Subject: [PATCH] PCI: Fix bus align checking to support more than 2G > > current 2G is out of date. > > -v3: We only need to extend that when 64bit mmio is supported. > So extract mmio64 mask checking, and still keep old 2G checking > for other path. --- Yinghai > > Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx> > > --- > drivers/pci/setup-bus.c | 42 ++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 38 insertions(+), 4 deletions(-) > > Index: linux-2.6/drivers/pci/setup-bus.c > =================================================================== > --- linux-2.6.orig/drivers/pci/setup-bus.c > +++ linux-2.6/drivers/pci/setup-bus.c > @@ -921,7 +921,7 @@ static int pbus_size_mem(struct pci_bus > { > struct pci_dev *dev; > resource_size_t min_align, align, size, size0, size1; > - resource_size_t aligns[12]; /* Alignments from 1Mb to 2Gb */ > + resource_size_t aligns[44]; /* Alignments from 1Mb to 2^63 */ > int order, max_order; > struct resource *b_res = find_free_bus_resource(bus, type); > unsigned int mem64_mask = 0; > @@ -937,6 +937,40 @@ static int pbus_size_mem(struct pci_bus > mem64_mask = b_res->flags & IORESOURCE_MEM_64; > b_res->flags &= ~IORESOURCE_MEM_64; > > + /* kernel does not support 64bit */ > + if (sizeof(resource_size_t) == 4) > + mem64_mask &= ~IORESOURCE_MEM_64; > + > + if (!(mem64_mask & IORESOURCE_MEM_64)) > + goto mem64_mask_check_done; > + > + /* check if mem64 support is supported and needed at first */ > + list_for_each_entry(dev, &bus->devices, bus_list) { > + int i; > + > + for (i = 0; i < PCI_NUM_RESOURCES; i++) { > + struct resource *r = &dev->resource[i]; > + resource_size_t r_size; > + > + if (r->parent || (r->flags & mask) != type) > + continue; > + r_size = resource_size(r); > +#ifdef CONFIG_PCI_IOV > + /* put SRIOV requested res to the optional list */ > + if (realloc_head && i >= PCI_IOV_RESOURCES && > + i <= PCI_IOV_RESOURCE_END) > + continue; > +#endif > + mem64_mask &= r->flags & IORESOURCE_MEM_64; > + > + if (!(mem64_mask & IORESOURCE_MEM_64)) > + goto mem64_mask_check_done; > + > + } > + } > + > +mem64_mask_check_done: > + > list_for_each_entry(dev, &bus->devices, bus_list) { > int i; > > @@ -959,8 +993,9 @@ static int pbus_size_mem(struct pci_bus > #endif > /* For bridges size != alignment */ > align = pci_resource_alignment(dev, r); > - order = __ffs(align) - 20; > - if (order > 11) { > + order = __ffs64(align) - 20; > + if (order > ARRAY_SIZE(aligns) || > + (!(mem64_mask & IORESOURCE_MEM_64) && order > 11) ) { ... > For 64bit systems, we want to ensure that the align < 1^63, so shouldn't > order be checked against 43, instead of ARRAY_SIZE(aligns) ? yes, should change to 43. Thanks Yinghai -- 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
