From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qc0-f202.google.com ([209.85.216.202]:60514 "EHLO mail-qc0-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753611Ab2GQArS (ORCPT ); Mon, 16 Jul 2012 20:47:18 -0400 Received: by qcqs25 with SMTP id s25so624913qcq.1 for ; Mon, 16 Jul 2012 17:47:16 -0700 (PDT) Date: Mon, 16 Jul 2012 18:47:16 -0600 From: Bjorn Helgaas To: Gavin Shan Cc: linux-pci@vger.kernel.org, linuxppc-dev@ozlabs.org, benh@kernel.crashing.org, yinghai@kernel.org, linuxram@us.ibm.com Subject: Re: [PATCH 05/15] pci: resource assignment based on p2p alignment Message-ID: <20120717004716.GC32203@google.com> References: <1342452631-21152-5-git-send-email-shangw@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1342452631-21152-5-git-send-email-shangw@linux.vnet.ibm.com> Sender: linux-pci-owner@vger.kernel.org List-ID: On Mon, Jul 16, 2012 at 11:30:28PM +0800, Gavin Shan wrote: > The patch changes function pbus_size_io() and pbus_size_mem() to > do resource (I/O, memory and prefetchable memory) reassignment > based on the minimal alignments for the p2p bridge, which was > retrieved by function pcibios_window_alignment(). > > Signed-off-by: Gavin Shan > --- > drivers/pci/setup-bus.c | 22 +++++++++++++++------- > 1 files changed, 15 insertions(+), 7 deletions(-) > > diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c > index 8fa2d4b..6ccf31a 100644 > --- a/drivers/pci/setup-bus.c > +++ b/drivers/pci/setup-bus.c > @@ -710,6 +710,7 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, > struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO); > unsigned long size = 0, size0 = 0, size1 = 0; > resource_size_t children_add_size = 0; > + resource_size_t io_align; > > if (!b_res) > return; > @@ -735,13 +736,15 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, > children_add_size += get_res_add_size(realloc_head, r); > } > } > + > + io_align = pcibios_window_alignment(bus, IORESOURCE_IO); > size0 = calculate_iosize(size, min_size, size1, > - resource_size(b_res), 4096); > + resource_size(b_res), io_align); > if (children_add_size > add_size) > add_size = children_add_size; > size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 : > calculate_iosize(size, min_size, add_size + size1, > - resource_size(b_res), 4096); > + resource_size(b_res), io_align); > if (!size0 && !size1) { > if (b_res->start || b_res->end) > dev_info(&bus->self->dev, "disabling bridge window " > @@ -751,11 +754,11 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, > return; > } > /* Alignment of the IO window is always 4K */ > - b_res->start = 4096; > + b_res->start = io_align; > b_res->end = b_res->start + size0 - 1; > b_res->flags |= IORESOURCE_STARTALIGN; > if (size1 > size0 && realloc_head) { > - add_to_list(realloc_head, bus->self, b_res, size1-size0, 4096); > + add_to_list(realloc_head, bus->self, b_res, size1-size0, io_align); > dev_printk(KERN_DEBUG, &bus->self->dev, "bridge window " > "%pR to [bus %02x-%02x] add_size %lx\n", b_res, > bus->secondary, bus->subordinate, size1-size0); > @@ -785,10 +788,15 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, > struct resource *b_res = find_free_bus_resource(bus, type); > unsigned int mem64_mask = 0; > resource_size_t children_add_size = 0; > + resource_size_t mem_align; > + int mem_align_shift; > > if (!b_res) > return 0; > > + mem_align = pcibios_window_alignment(bus, type); > + mem_align_shift = __ffs(mem_align); > + > memset(aligns, 0, sizeof(aligns)); > max_order = 0; > size = 0; > @@ -818,8 +826,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, > #endif > /* For bridges size != alignment */ > align = pci_resource_alignment(dev, r); > - order = __ffs(align) - 20; > - if (order > 11) { > + order = __ffs(align) - mem_align_shift; > + if (order > (11 - (mem_align_shift - 20))) { This doesn't seem right to me. Aren't we accumulating the amount of space required at each alignment in aligns[]? That should be independent of whatever arch-specific minimum alignment we have. Does it have to be more complicated than something like this at the very end? min_align = max(min_align, pci_window_alignment(bus, IORESOURCE_MEM)); > dev_warn(&dev->dev, "disabling BAR %d: %pR " > "(bad alignment %#llx)\n", i, r, > (unsigned long long) align); > @@ -846,7 +854,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, > for (order = 0; order <= max_order; order++) { > resource_size_t align1 = 1; > > - align1 <<= (order + 20); > + align1 <<= (order + mem_align_shift); > > if (!align) > min_align = align1; > -- > 1.7.5.4 >