People reported that they can not do a poweroff nor a suspend to ram on their Mac Pro 11. After some investigations it was found that, once the PCI bridge 0000:00:1c.0 reassigns its mm windows to ([mem 0x7fa00000-0x7fbfffff] and [mem 0x7fc00000-0x7fdfffff 64bit pref]), the region of ACPI io resource 0x1804 becomes unaccessible immediately, where the ACPI Sleep register is located, as a result neither poweroff(S5) nor suspend to ram(S3) works. As suggested by Bjorn, further testing shows that, there is an unreported device may be (using) conflict with above aperture, which brings unpredictable result such as the failure of accessing the io port, which blocks the poweroff(S5). Besides if we reassign the memory aperture to the other place, the poweroff works again. As we do not find any resource declared in _CRS which contain above memory aperture, and Mac OS does not use this pci bridge neither, we choose a simple workaround to clear the hotplug flag(suggested by Yinghai Lu), thus do not allocate any resource for this pci bridge, and thereby no conflict anymore. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=103211 Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Cc: Rafael J. Wysocki <rafael@xxxxxxxxxx> Cc: Lukas Wunner <lukas@xxxxxxxxx> Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx> --- drivers/pci/quirks.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 37ff015..04bbdba 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2776,6 +2776,26 @@ static void quirk_hotplug_bridge(struct pci_dev *dev) DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_HINT, 0x0020, quirk_hotplug_bridge); /* + * Apple: Avoid programming the memory/io aperture of 00:1c.0 + * + * BIOS does not declare any resource for 00:1c.0, but with + * hotplug flag set, thus the OS allocates: + * [mem 0x7fa00000 - 0x7fbfffff] + * [mem 0x7fc00000-0x7fdfffff 64bit pref] + * which is conflict with an unreported device, which + * causes unpredictable result such as accessing io port. + * So clear the hotplug flag to work around it. + */ +static void quirk_apple_mbp_poweroff(struct pci_dev *dev) +{ + if (dmi_match(DMI_PRODUCT_NAME, "MacBookPro11,4") || + dmi_match(DMI_PRODUCT_NAME, "MacBookPro11,5")) + dev->is_hotplug_bridge = 0; +} + +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x8c10, quirk_apple_mbp_poweroff); + +/* * This is a quirk for the Ricoh MMC controller found as a part of * some mulifunction chips. -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
