[PATCH] ARM: footbridge: fix overlapping PCI mappings

[Rob Herring]

On Thu, Jun 27, 2013 at 9:42 PM, Mike Frysinger <vapier at gentoo.org> wrote:
> 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>

Acked-by: Rob Herring <rob.herring at calxeda.com>

Olof, Kevin,

Please apply and add stable.

Rob

> ---
>  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);
>
> --
> 1.8.2.1
>
>
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