On 5/18/2015 10:33 AM, Jarod Wilson wrote:
On 5/17/2015 8:26 PM, Rafael J. Wysocki wrote:
On Saturday, May 16, 2015 09:41:55 AM Bjorn Helgaas wrote:
On Sat, May 16, 2015 at 09:37:50AM -0500, Bjorn Helgaas wrote:
Hi Jarod,
On Thu, May 14, 2015 at 03:33:58PM -0400, Jarod Wilson wrote:
The HP ZBook 15 and 17 Mobile Workstations, generation 2, up to and
including at least BIOS revision 01.07, do not have an ACPI _RMV
object
associated with their expresscard slots, so acpi-based hotplug-capable
slot detection fails. If we fall back to pcie-based detection, the
systems
work just fine, so this uses dmi matching to do that. With luck, a
future
BIOS will remedy this (I've let someone at HP know about the problem),
but for now, just use this for all existing versions.
...
Oh, my goodness. I forgot how terrible this path is. Can anyone
write a
simple explanation of how we choose to use acpiphp or pciehp?
In theory, that should depend on the _OSC handshake in
acpi_pci_root_add().
If the firmware doesn't give us control of the PCIe features, we'll
not use
pciehp (or at least that's the idea).
acpiphp is used if pciehp doesn't claim the device, AFAICS.
[ 4.013326] acpi PNP0A08:00: _OSC: OS supports [ExtendedConfig ASPM
ClockPM Segments MSI]
[ 4.015860] acpi PNP0A08:00: _OSC: OS now controls [PCIeHotplug PME
AER PCIeCapability]
So at a glance, it would appear that pciehp *should* be claiming it,
right? Something I noted in the bug I filed is that the device ID
reported there is PNP0A08, and the root_device_id table that associates
with acpi_pci_root_add() only includes PNP0A03 in it. Is that correct,
or should 08 also be in there, which might remedy this? (I can test this
out easily enough).
Nope, makes no difference, seems those are just two different references
to the same bus, based on a peek at the extracted dsdt:
Name (_HID, EisaId ("PNP0A08") /* PCI Express Bus */) // _HID: Hardware ID
Name (_CID, EisaId ("PNP0A03") /* PCI Bus */) // _CID: Compatible ID
--
Jarod Wilson
jarod@xxxxxxxxxx
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