[PATCH] ARM: footbridge: fix overlapping PCI mappings

Mike Frysinger vapier at gentoo.org
Thu Jun 27 22:42:36 EDT 2013

Commit 8ef6e6201b26cb9fde79c1baa08145af6aca2815 (ARM: footbridge: use
fixed PCI i/o mapping) broke booting on my netwinder.  Before that,
everything boots fine.  Since then, it crashes on boot.

With earlyprintk, I see it BUG-ing like so:
kernel BUG at lib/ioremap.c:27!
Internal error: Oops - BUG: 0 [#1] ARM
[<c0139b54>] (ioremap_page_range+0x128/0x154) from [<c02e6a6c>] (dc21285_setup+0xd0/0x114)
[<c02e6a6c>] (dc21285_setup+0xd0/0x114) from [<c02e4874>] (pci_common_init+0xa0/0x298)
[<c02e4874>] (pci_common_init+0xa0/0x298) from [<c02e793c>] (netwinder_pci_init+0xc/0x18)
[<c02e793c>] (netwinder_pci_init+0xc/0x18) from [<c02e27d0>] (do_one_initcall+0xb4/0x180)

Russell points out it's because of overlapping PCI mappings that was
added with the aforementioned commit.  Rob thought the code would re-use
the static mapping, but that turns out to not be the case and instead
hits the BUG further down.

After deleting this hunk as suggested by Russel, the system boots up fine
again and all my PCI devices work (IDE, ethernet, the DC21285).

Signed-off-by: Mike Frysinger <vapier at gentoo.org>
 arch/arm/mach-footbridge/dc21285.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/arm/mach-footbridge/dc21285.c b/arch/arm/mach-footbridge/dc21285.c
index a7cd2cf..3490a24 100644
--- a/arch/arm/mach-footbridge/dc21285.c
+++ b/arch/arm/mach-footbridge/dc21285.c
@@ -276,8 +276,6 @@ int __init dc21285_setup(int nr, struct pci_sys_data *sys)
 	sys->mem_offset  = DC21285_PCI_MEM;
-	pci_ioremap_io(0, DC21285_PCI_IO);
 	pci_add_resource_offset(&sys->resources, &res[0], sys->mem_offset);
 	pci_add_resource_offset(&sys->resources, &res[1], sys->mem_offset);

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