Re: ACPIPNP and too large IO resources

Bjorn Helgaas <bjorn.helgaas@xxxxxx> wrote:

On Wednesday 05 July 2006 14:53, Pierre Ossman wrote:
Bjorn Helgaas wrote:
It sounds like this might be the same problem as
http://bugzilla.kernel.org/show_bug.cgi?id=6292

In short, you probably have a bridge device that consumes the
entire 0x0-0xffff I/O port range and produces some or all of that
range for downstream PNP devices. PNP doesn't know what to do
with these windows that are both consumed by the bridge and made
available to downstream devices, so it just marks them as being
already reserved.

Ah, that explains things.

Matthieu Castet wrote a nice patch (attached) that makes PNP just
ignore those windows. Can you try it and see whether it fixes
the problem you're seeing? This patch is already in -mm, but not
yet in mainline. We might need to consider this patch as
2.6.18 material if it resolves your problem. I suspect many
people will see the same problem.

The patch works nicely and removes all memory and io regions for the PCI
bridge but for the range 0xcf8-0xcff.

Andrew, I think we should try again to push
pnpacpi-reject-acpi_producer-resources.patch to the mainline.

Pierre's report (starts here: http://lkml.org/lkml/2006/7/5/20)
is another instance of http://bugzilla.kernel.org/show_bug.cgi?id=6292.

I suspect that many PNP devices are broken in 2.6.17 because of
this problem. Probably the only reason we haven't seen more
reports is that PNPACPI isn't turned on by default. (Maybe
we should do that in -mm?)

You recently proposed pushing it:
http://marc.theaimsgroup.com/?l=linux-acpi&m=115119275408021&w=2
Len initially nacked it, but I think the outcome of the discussion
is that Shaohua doesn't object to this patch. He probably would
still like to blacklist PNP0A03, but that's an additional step we
don't have to take at the same time.


OK, well let's please push this up the priority list and work out what want
to do. If Len's now OK with merging it then I think all lights are green?

pnpacpi-reject-acpi_producer-resources.patch:

From: matthieu castet <castet.matthieu@xxxxxxx>

A patch in -mm kernel correct the parsing of "address resources" of pnpacpi.
Before we assumed it was memory only, but it could be also IO.

But this change show an hidden bug : some resources could be producer type
that are not handled by pnp layer. So we should ignore the producer
resources.

This patch fixes bug 6292 (http://bugzilla.kernel.org/show_bug.cgi?id=6292).
Some devices like PNP0A03 have 0xd00-0xffff and 0x0-0xcf7 as IO producer
resources.

Before correcting "address resources" parsing, it was seen as memory and was
harmless, because nobody tried to reserve this memory range as it should be
IO.

With the correction it become IO resources, and make failed all others device
that want to register IO in this range and use pnp layer (like a ISA sound
card).

The solution is to ignore producer resources

Signed-off-by: Matthieu CASTET <castet.matthieu@xxxxxxx>
Signed-off-by: Uwe Bugla <uwe.bugla@xxxxxx>
Cc: Bjorn Helgaas <bjorn.helgaas@xxxxxx>
Cc: Adam Belay <ambx1@xxxxxxxxxx>
Cc: "Brown, Len" <len.brown@xxxxxxxxx>

akpm: previously nacked, as per comment #26. But am hanging onto it until the
thing gets fixed for real.

Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---

drivers/pnp/pnpacpi/rsparser.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff -puN drivers/pnp/pnpacpi/rsparser.c~pnpacpi-reject-acpi_producer-resources drivers/pnp/pnpacpi/rsparser.c
--- a/drivers/pnp/pnpacpi/rsparser.c~pnpacpi-reject-acpi_producer-resources
+++ a/drivers/pnp/pnpacpi/rsparser.c
@@ -173,6 +173,9 @@ pnpacpi_parse_allocated_address_space(st
return;
}

+ if (p->producer_consumer == ACPI_PRODUCER)
+ return;
+
if (p->resource_type == ACPI_MEMORY_RANGE)
pnpacpi_parse_allocated_memresource(res_table,
p->minimum, p->address_length);
@@ -252,9 +255,14 @@ static acpi_status pnpacpi_allocated_res
break;

case ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64:
+ if (res->data.ext_address64.producer_consumer == ACPI_PRODUCER)
+ return AE_OK;
break;

case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+ if (res->data.extended_irq.producer_consumer == ACPI_PRODUCER)
+ return AE_OK;
+
for (i = 0; i < res->data.extended_irq.interrupt_count; i++) {
pnpacpi_parse_allocated_irqresource(res_table,
res->data.extended_irq.interrupts[i],
_

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