From 3134233097791ae64002a51c2c8c9bf2ab200ea0 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Tue, 11 Apr 2017 17:33:12 +0100 Subject: [PATCH 1/2] PCI: Do not disregard parent resources starting at 0x0 Commit f44116ae8818 ("PCI: Remove pci_find_parent_resource() use for allocation") updated the logic that iterates over all bus resources and compares them to a given resource, in order to decide whether one is the parent of the latter. This change inadvertently causes pci_find_parent_resource() to disregard resources starting at address 0x0, resulting in an error such as the one below on ARM systems whose I/O window starts at 0x0. pci_bus 0000:00: root bus resource [mem 0x10000000-0x3efeffff window] pci_bus 0000:00: root bus resource [io 0x0000-0xffff window] pci_bus 0000:00: root bus resource [mem 0x8000000000-0xffffffffff window] pci_bus 0000:00: root bus resource [bus 00-0f] pci 0000:00:01.0: PCI bridge to [bus 01] pci 0000:00:02.0: PCI bridge to [bus 02] pci 0000:00:03.0: PCI bridge to [bus 03] pci 0000:00:03.0: can't claim BAR 13 [io 0x0000-0x0fff]: no compatible bridge window pci 0000:03:01.0: can't claim BAR 0 [io 0x0000-0x001f]: no compatible bridge window While this never happens on x86, it is perfectly legal in general for a PCI MMIO or IO window to start at address 0x0, and it was supported in the code before commit f44116ae8818. Drop the test for res->start != 0; resource_contains() already checks whether [start, end) completely covers the resource, and so it should be redundant. Signed-off-by: Ard Biesheuvel Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b01bd5bba8e6..d5575f6b9c62 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -455,7 +455,7 @@ struct resource *pci_find_parent_resource(const struct pci_dev *dev, pci_bus_for_each_resource(bus, r, i) { if (!r) continue; - if (res->start && resource_contains(r, res)) { + if (resource_contains(r, res)) { /* * If the window is prefetchable but the BAR is From 13cfc732160f7bc7e596128ce34cda361c556966 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Fri, 19 Aug 2016 16:30:25 +0800 Subject: [PATCH 2/2] PCI: Work around poweroff & suspend-to-RAM issue on Macbook Pro 11 Neither soft poweroff (transition to ACPI power state S5) nor suspend-to-RAM (transition to state S3) works on the Macbook Pro 11,4 and 11,5. The problem is related to the [mem 0x7fa00000-0x7fbfffff] space. When we use that space, e.g., by assigning it to the 00:1c.0 Root Port, the ACPI Power Management 1 Control Register (PM1_CNT) at [io 0x1804] doesn't work anymore. Linux does a soft poweroff (transition to S5) by writing to PM1_CNT. The theory about why this doesn't work is: - The write to PM1_CNT causes an SMI - The BIOS SMI handler depends on something in [mem 0x7fa00000-0x7fbfffff] - When Linux assigns [mem 0x7fa00000-0x7fbfffff] to the 00:1c.0 Port, it covers up whatever the SMI handler uses, so the SMI handler no longer works correctly Reserve the [mem 0x7fa00000-0x7fbfffff] space so we don't assign it to anything. This is voodoo programming, since we don't know what the real conflict is, but we've failed to find the root cause. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=103211 Tested-by: thejoe@gmail.com Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org Cc: Rafael J. Wysocki Cc: Lukas Wunner Cc: Chen Yu --- arch/x86/pci/fixup.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c index 6d52b94f4bb9..20fa7c84109d 100644 --- a/arch/x86/pci/fixup.c +++ b/arch/x86/pci/fixup.c @@ -571,3 +571,35 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2fc0, pci_invalid_bar); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6f60, pci_invalid_bar); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fa0, pci_invalid_bar); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fc0, pci_invalid_bar); + +/* + * Apple MacBook Pro: Avoid [mem 0x7fa00000-0x7fbfffff] + * + * Using the [mem 0x7fa00000-0x7fbfffff] region, e.g., by assigning it to + * the 00:1c.0 Root Port, causes a conflict with [io 0x1804], which is used + * for soft poweroff and suspend-to-RAM. + * + * As far as we know, this is related to the address space, not to the Root + * Port itself. Attaching the quirk to the Root Port is a convenience, but + * it could probably also be a standalone DMI quirk. + * + * https://bugzilla.kernel.org/show_bug.cgi?id=103211 + */ +static void quirk_apple_mbp_poweroff(struct pci_dev *pdev) +{ + struct device *dev = &pdev->dev; + struct resource *res; + + if ((!dmi_match(DMI_PRODUCT_NAME, "MacBookPro11,4") && + !dmi_match(DMI_PRODUCT_NAME, "MacBookPro11,5")) || + pdev->bus->number != 0 || pdev->devfn != PCI_DEVFN(0x1c, 0)) + return; + + res = request_mem_region(0x7fa00000, 0x200000, + "MacBook Pro poweroff workaround"); + if (res) + dev_info(dev, "claimed %s %pR\n", res->name, res); + else + dev_info(dev, "can't work around MacBook Pro poweroff issue\n"); +} +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x8c10, quirk_apple_mbp_poweroff);