Hi Ilya,
On Tue, Apr 13, 2021 at 08:12:37PM -0700, Ilya Lipnitskiy wrote:
> Mirror commit aeba3731b150 ("powerpc/pci: Fix IO space breakage after
> of_pci_range_to_resource() change").
>
> Most MIPS platforms do not define PCI_IOBASE, nor implement
> pci_address_to_pio(). Moreover, IO_SPACE_LIMIT is 0xffff for most MIPS
> platforms. of_pci_range_to_resource passes the _start address_ of the IO
> range into pci_address_to_pio, which then checks it against
> IO_SPACE_LIMIT and fails, because for MIPS platforms that use
> pci-legacy (pci-lantiq, pci-rt3883, pci-mt7620), IO ranges start much
> higher than 0xffff.
I think defining PCI_IOBASE and implementing pci_address_to_pio() would be
easier in the long run as you will then let the core PCI code do most of
the work, but given that this is legacy code I can understand that testing
it would not be simple.
>
> In fact, pci-mt7621 in staging already works around this problem, see
> commit 09dd629eeabb ("staging: mt7621-pci: fix io space and properly set
> resource limits")
>
> So just stop using of_pci_range_to_resource, which does not work for
> MIPS.
>
> Fixes PCI errors like:
> pci_bus 0000:00: root bus resource [io 0xffffffff]
>
> Fixes: 0b0b0893d49b ("of/pci: Fix the conversion of IO ranges into IO resources")
> Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@xxxxxxxxx>
> Cc: Liviu Dudau <Liviu.Dudau@xxxxxxx>
> ---
> arch/mips/pci/pci-legacy.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/arch/mips/pci/pci-legacy.c b/arch/mips/pci/pci-legacy.c
> index 39052de915f3..3a909194284a 100644
> --- a/arch/mips/pci/pci-legacy.c
> +++ b/arch/mips/pci/pci-legacy.c
> @@ -166,8 +166,13 @@ void pci_load_of_ranges(struct pci_controller *hose, struct device_node *node)
> res = hose->mem_resource;
> break;
> }
> - if (res != NULL)
> - of_pci_range_to_resource(&range, node, res);
> + if (res != NULL) {
> + res->name = node->full_name;
> + res->flags = range.flags;
> + res->start = range.cpu_addr;
> + res->end = range.cpu_addr + range.size - 1;
> + res->parent = res->child = res->sibling = NULL;
> + }
Change looks reasonable to me.
Reviewed-by: Liviu Dudau <liviu.dudau@xxxxxxx>
Best regards,
Liviu
> }
> }
>
> --
> 2.31.1
>
--
====================
| I would like to |
| fix the world, |
| but they're not |
| giving me the |
\ source code! /
---------------
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