Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754094AbbEPOh5 (ORCPT ); Sat, 16 May 2015 10:37:57 -0400 Received: from mail-ig0-f174.google.com ([209.85.213.174]:37414 "EHLO mail-ig0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751570AbbEPOhy (ORCPT ); Sat, 16 May 2015 10:37:54 -0400 Date: Sat, 16 May 2015 09:37:50 -0500 From: Bjorn Helgaas To: Jarod Wilson Cc: linux-kernel@vger.kernel.org, Len Brown , "Rafael J. Wysocki" , linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org Subject: Re: [PATCH] pci/hotplug: work-around for missing _RMV on HP ZBook G2 Message-ID: <20150516143750.GG31666@google.com> References: <1431632038-39917-1-git-send-email-jarod@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1431632038-39917-1-git-send-email-jarod@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4142 Lines: 113 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. > > Note: they *do* have a proper _RMV object for what I believe is their > thunderbolt ports. > > Tested successfully on an HP ZBook 17 G2 and HP ZBook 15 G2. > > CC: Len Brown > CC: "Rafael J. Wysocki" > CC: Bjorn Helgaas > CC: linux-acpi@vger.kernel.org > CC: linux-pci@vger.kernel.org > Signed-off-by: Jarod Wilson > --- > drivers/pci/hotplug/pciehp_acpi.c | 33 +++++++++++++++++++++++++++++++++ > 1 file changed, 33 insertions(+) > > diff --git a/drivers/pci/hotplug/pciehp_acpi.c b/drivers/pci/hotplug/pciehp_acpi.c > index 93cc926..db38fb5 100644 > --- a/drivers/pci/hotplug/pciehp_acpi.c > +++ b/drivers/pci/hotplug/pciehp_acpi.c > @@ -28,6 +28,7 @@ > #include > #include > #include > +#include > #include "pciehp.h" > > #define PCIEHP_DETECT_PCIE (0) > @@ -109,10 +110,40 @@ static struct pcie_port_service_driver __initdata dummy_driver = { > .probe = dummy_probe, > }; > > +static int __init set_slot_detection_mode_pcie(const struct dmi_system_id *d) > +{ > + info("%s lacks ACPI _RMV object for expresscard\n", d->ident); > + return 1; > +} > + > +static struct dmi_system_id __initdata missing_acpi_rmv[] = { > + /* ZBook 17 through at least bios v01.07 */ > + { > + .callback = set_slot_detection_mode_pcie, > + .ident = "HP ZBook 17 G2 Mobile Workstation", > + .matches = { > + DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), > + DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 17 G2"), > + }, > + }, > + /* ZBook 15 through at least bios v01.07 */ > + { > + .callback = set_slot_detection_mode_pcie, > + .ident = "HP ZBook 15 G2 Mobile Workstation", > + .matches = { > + DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), > + DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 15 G2"), > + }, > + }, > + { .ident = NULL } > +}; > + > static int __init select_detection_mode(void) > { > struct dummy_slot *slot, *tmp; > > + if (dmi_check_system(missing_acpi_rmv)) > + return PCIEHP_DETECT_PCIE; 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? Module parameters? A dummy driver that looks for duplicate slot numbers? Looking for _ADR, _EJ0, _RMV? This is just nuts. I can't really believe that we're doing this correctly. If I understand correctly, the ZBooks don't have _RMV, but we try to use acpiphp anyway, and acpiphp doesn't work? That sounds more like a problem with our acpiphp/pciehp selection "algorithm" than a BIOS bug. Jarod, can you open a report at http://bugzilla.kernel.org and attach a complete dmesg log, "lspci -vv" output, and an acpidump? I'm particularly interested in whether the BIOS granted us control over PCIe native hotplug. If it did, I wonder why we would even attempt to use acpiphp. Bjorn > if (pcie_port_service_register(&dummy_driver)) > return PCIEHP_DETECT_ACPI; > pcie_port_service_unregister(&dummy_driver); > @@ -134,4 +165,6 @@ void __init pciehp_acpi_slot_detection_init(void) > out: > if (slot_detection_mode == PCIEHP_DETECT_ACPI) > info("Using ACPI for slot detection.\n"); > + else if (slot_detection_mode == PCIEHP_DETECT_PCIE) > + info("Using PCIE-based slot detection.\n"); > } > -- > 1.8.3.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/