Hi Bjorn,
On 2016年05月31日 05:33, Bjorn Helgaas wrote:
On Mon, May 30, 2016 at 06:33:24PM +0800, Chen Yu wrote:
Currently there are many people reported that they can not
do a poweroff nor a suspend to memory on their Mac Pro 11.
After some investigations it was found that, once the PCI bridge
0000:00:1c.0 reassigns its mm windows([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 memory(S3) works.
I don't know why setting the base/limit of PCI bridge mem resource
would affect another io resource region, so this quirk just simply
bypass the assignment of these mm resources on 0000:00:1c.0, by
resetting the resource flag to 0 before updating the base/limit registers.
This patch also introduces a new pci fixup phase before the actual bridge
resource assignment.
Split the new fixup phase into a separate patch.
I'm doubtful about this because we don't understand the root cause.
Yes, I don't know the root cause neither, so I send this patch to ask for
help, maybe we should also invite Apple people in..
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=103211
Tested-by: Cedric Le Goater <clg@xxxxxxxx>
Tested-by: pkozlov <pkozlov.vrn@xxxxxxxxx>
Tested-by: Zach Norman <zach@xxxxxx>
Tested-by: Pablo Catalina <pablo.catalina@xxxxxxxxx>
Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx>
---
drivers/pci/quirks.c | 25 +++++++++++++++++++++++++
drivers/pci/setup-bus.c | 2 ++
include/asm-generic/vmlinux.lds.h | 3 +++
include/linux/pci.h | 4 ++++
scripts/mod/modpost.c | 1 +
5 files changed, 35 insertions(+)
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index ee72ebe..e347047 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3370,6 +3370,8 @@ extern struct pci_fixup __start_pci_fixups_header[];
extern struct pci_fixup __end_pci_fixups_header[];
extern struct pci_fixup __start_pci_fixups_final[];
extern struct pci_fixup __end_pci_fixups_final[];
+extern struct pci_fixup __start_pci_fixups_assign[];
+extern struct pci_fixup __end_pci_fixups_assign[];
extern struct pci_fixup __start_pci_fixups_enable[];
extern struct pci_fixup __end_pci_fixups_enable[];
extern struct pci_fixup __start_pci_fixups_resume[];
@@ -3405,6 +3407,11 @@ void pci_fixup_device(enum pci_fixup_pass pass, struct pci_dev *dev)
end = __end_pci_fixups_final;
break;
+ case pci_fixup_assign:
+ start = __start_pci_fixups_assign;
+ end = __end_pci_fixups_assign;
+ break;
+
case pci_fixup_enable:
start = __start_pci_fixups_enable;
end = __end_pci_fixups_enable;
@@ -4419,3 +4426,21 @@ static void quirk_intel_qat_vf_cap(struct pci_dev *pdev)
}
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x443, quirk_intel_qat_vf_cap);
+
+/*
+ * On Mac Pro 11, the allocation of pci bridge memory resource
+ * broke ACPI Sleep Type register region.
+ */
+static void quirk_mac_disable_mmio_bar(struct pci_dev *dev)
+{
+ struct resource *b_res;
+
+ dev_info(&dev->dev, "[Quirk] Disable mmio on Mac Pro 11\n");
+ if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
+ return;
Why test for PCI_CLASS_BRIDGE_PCI? If you do need to test, why is the
test after the dev_info()?
This checking is not needed, since we only invoke
pci_fixup_device(pci_fixup_assign)
for bridges. I can remove it.
+ b_res = &dev->resource[PCI_BRIDGE_RESOURCES];
+ b_res[1].flags = 0;
+ b_res[2].flags = 0;
You're changing the resource flags but not the hardware itself. I
assume the window is still enabled and still claims address space, so
we don't want to throw away the information about it, because then we
don't know whether downstream devices can work, and we can't safely
assign resources to peers.
If I understand correctly, according to the boot logs, the pci bridge
in question has not declaimed any valid device/bridge resource
(both io and mem) during probe(because base=0xfff>limit=0x0),
so I think it has not hardware resource setting at that time(at least
in BIOS)
until it reaches pcibios_assign_resources and it has to allocate a
minimal io/mem resource, then it tries to assign them to
[mem 0x7fa00000 - 0x7fbfffff]
[mem 0x7fc00000-0x7fdfffff 64bit pref]
[io 0x2000-0x2fff],
so if we reset the flag to zero for these mem resource, the pci bridge
will not assign any pci mem windows for it
(in this way
find_free_bus_resource(bus, mask | IORESOURCE_PREFETCH, type)
will not return any free resource, thus bypass the assignment)
According to the boot log at
https://bugzilla.kernel.org/attachment.cgi?id=210141
, we can see there is no bridge windows assign for 0000:00:1c.0 during
early probe:
[ 0.807893] pci 0000:00:1c.0: [8086:8c10] type 01 class 0x060400
[ 0.807949] pci 0000:00:1c.0: PME# supported from D0 D3hot D3cold
[ 0.831281] pci 0000:00:1c.0: PCI bridge to [bus 02]
and then in pcibios_assign_resources, 0000:00:1c.0 tries to allocate minimal
resource window and then update related base/limit registers:
[ 0.865342] pci 0000:00:1c.0: bridge window [io 0x1000-0x0fff] to
[bus 02] add_size 1000
[ 0.865343] pci 0000:00:1c.0: bridge window [mem
0x00100000-0x000fffff 64bit pref] to [bus 02] add_size 200000 add_align
100000
[ 0.865344] pci 0000:00:1c.0: bridge window [mem
0x00100000-0x000fffff] to [bus 02] add_size 200000 add_align 100000
+}
+DECLARE_PCI_FIXUP_ASSIGN(PCI_VENDOR_ID_INTEL, 0x8c10, quirk_mac_disable_mmio_bar);
Is this device *only* used on the Mac Pro 11? http://pci-ids.ucs.cz
says "8 Series/C220 Series Chipset Family PCI Express Root Port #1",
which sounds pretty generic.
Maybe not only used for Mac Pro 11, so should it be a dmi match+pci quirk?
thanks,
Yu
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