From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754036Ab1DKO4b (ORCPT ); Mon, 11 Apr 2011 10:56:31 -0400 Received: from mail201c2.megamailservers.com ([69.49.111.102]:43074 "EHLO mail201c2.megamailservers.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752956Ab1DKO4a (ORCPT ); Mon, 11 Apr 2011 10:56:30 -0400 X-Authenticated-User: daniel.gaisler.com Message-ID: <4DA31603.6070308@gaisler.com> Date: Mon, 11 Apr 2011 16:53:55 +0200 From: Daniel Hellstrom User-Agent: Mozilla Thunderbird 1.0.6 (X11/20050716) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Linus Torvalds CC: Ram Pai , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Clemens Ladisch , Yinghai Lu , Kristoffer Glembo Subject: Re: [PATCH 1/4] PCI: refactor io size calculation code References: <4DA2FFB6.3040209@gaisler.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-CSC: 0 X-CHA: v=1.1 cv=Ma2F9VxktdrohpwE1Ldo3j5zboDzDSax3kyf6Hawm04= c=1 sm=1 a=pl2ZPvC6udcA:10 a=liV55vvCHxUA:10 a=U62ajLuCel8A:10 a=8nJEP1OIZ-IA:10 a=jXKJviUpWSOlMmIvGrHOfw==:17 a=ebG-ZW-8AAAA:8 a=7NxiOfhJNlJqVJIRXEAA:9 a=_TAhauMUqd7s4p3usnQA:7 a=wPNLvfGTeEIA:10 a=cCYF7-FHeg4A:10 a=jXKJviUpWSOlMmIvGrHOfw==:117 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus Torvalds wrote: >On Mon, Apr 11, 2011 at 6:18 AM, Daniel Hellstrom wrote: > > >>In commit 13583b16592a ("PCI: refactor io size calculation code"): >> >> >>>refactor code that calculates the io size in pbus_size_io() >>>and pbus_mem_io() into separate functions. >>> >>>Signed-off-by: Ram Pai >>>--- >>>drivers/pci/setup-bus.c | 66 >>>++++++++++++++++++++++++++++++----------------- >>>1 files changed, 42 insertions(+), 24 deletions(-) >>> >>>diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c >>>index 66cb8f4..2121215 100644 >>>--- a/drivers/pci/setup-bus.c >>>+++ b/drivers/pci/setup-bus.c >>>@@ -404,6 +404,43 @@ static struct resource *find_free_bus_resource(struct >>>pci_bus *bus, unsigned lon >>> return NULL; >>>} >>> >>> >>> >>... >> >> >> >>>+ >>>+static resource_size_t calculate_memsize(resource_size_t size, >>>+ resource_size_t min_size, >>>+ resource_size_t size1, >>>+ resource_size_t old_size, >>>+ resource_size_t align) >>>+{ >>>+ if (size < min_size) >>>+ size = min_size; >>>+ if (old_size == 1 ) >>>+ old_size = 0; >>>+ if (size < old_size) >>>+ size = old_size; >>>+ size = ALIGN(size + size1, align); >>>+ return size; >>>+} >>>+ >>>/* Sizing the IO windows of the PCI-PCI bridge is trivial, >>> since these windows have 4K granularity and the IO ranges >>> of non-bridge PCI devices are limited to 256 bytes. >>> >>> >>> >>> >>... >> >> >> >>>@@ -516,14 +542,6 @@ static int pbus_size_mem(struct pci_bus *bus, >>>unsigned long mask, >>> mem64_mask &= r->flags & IORESOURCE_MEM_64; >>> } >>> } >>>- if (size < min_size) >>>- size = min_size; >>>- old_size = resource_size(b_res); >>>- if (old_size == 1) >>>- old_size = 0; >>>- if (size < old_size) >>>- size = old_size; >>>- >>> align = 0; >>> min_align = 0; >>> for (order = 0; order <= max_order; order++) { >>>@@ -537,7 +555,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned >>>long mask, >>> min_align = align1 >> 1; >>> align += aligns[order]; >>> } >>>- size = ALIGN(size, min_align); >>>+ size = calculate_memsize(size, min_size, 0, resource_size(b_res), >>>align); >>> >>> >>> >>On my SPARC32/LEON4 PCI system I get overlapped areas, double mapped >>resources. Some BARs on PCIBUS0 are in the same non-prefetchable memory >>range as the secondary bus PCIBUS1. Changing align to min_align in the above >>call to calculate_memsize() fixes the problem, and the memory allocation is >>the same as with 2.6.36.4 kernel. >> >>I belive this is just a typo. >> >> > >It does seem that way. The original code used 'min_align' and 'align' >itself is meaningless in that place. > > Agree. >Can you confirm that the patch you talk about as fixing things is the attached? > > Linus > > Yes, the below patch works on the system that triggered the problem before. The last min_align was added in a later patch, I missed it initially. Thanks, Daniel >------------------------------------------------------------------------ > > drivers/pci/setup-bus.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > >diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c >index 89d0a6a88df7..ebf51ad1b714 100644 >--- a/drivers/pci/setup-bus.c >+++ b/drivers/pci/setup-bus.c >@@ -676,10 +676,10 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, > min_align = align1 >> 1; > align += aligns[order]; > } >- size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), align); >+ size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align); > size1 = !add_size ? size : > calculate_memsize(size, min_size+add_size, 0, >- resource_size(b_res), align); >+ resource_size(b_res), min_align); > if (!size0 && !size1) { > if (b_res->start || b_res->end) > dev_info(&bus->self->dev, "disabling bridge window " > >