On Fri, Oct 2, 2020 at 4:20 PM Deucher, Alexander <Alexander.Deucher@xxxxxxx> wrote: > > [AMD Public Use] > > > -----Original Message----- > > From: amd-gfx <amd-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of > > Rafael J. Wysocki > > Sent: Friday, October 2, 2020 10:17 AM > > To: Lukas Wunner <lukas@xxxxxxxxx> > > Cc: Aaron Zakhrov <aaron.zakhrov@xxxxxxxxx>; Michal Rostecki > > <mrostecki@xxxxxxxx>; Linux PCI <linux-pci@xxxxxxxxxxxxxxx>; Rafael J. > > Wysocki <rjw@xxxxxxxxxxxxx>; amd-gfx list <amd- > > gfx@xxxxxxxxxxxxxxxxxxxxx>; ACPI Devel Maling List <linux- > > acpi@xxxxxxxxxxxxxxx>; Shai Coleman <git@xxxxxxxxxxxxxxx>; Bjorn > > Helgaas <helgaas@xxxxxxxxxx>; Arthur Borsboom > > <arthurborsboom@xxxxxxxxx>; matoro <matoro@xxxxxxxxxx>; Deucher, > > Alexander <Alexander.Deucher@xxxxxxx>; Mika Westerberg > > <mika.westerberg@xxxxxxxxxxxxxxx>; Len Brown <lenb@xxxxxxxxxx> > > Subject: Re: [PATCH] PCI/ACPI: Whitelist hotplug ports for D3 if power > > managed by ACPI > > > > On Fri, Oct 2, 2020 at 7:17 AM Lukas Wunner <lukas@xxxxxxxxx> wrote: > > > > > > Recent laptops with dual AMD GPUs fail to suspend the discrete GPU, > > > thus causing lockups on system sleep and high power consumption at > > runtime. > > > The discrete GPU would normally be suspended to D3cold by turning off > > > ACPI _PR3 Power Resources of the Root Port above the GPU. > > > > > > However on affected systems, the Root Port is hotplug-capable and > > > pci_bridge_d3_possible() only allows hotplug ports to go to D3 if they > > > belong to a Thunderbolt device or if the Root Port possesses a > > > "HotPlugSupportInD3" ACPI property. Neither is the case on affected > > > laptops. The reason for whitelisting only specific, known to work > > > hotplug ports for D3 is that there have been reports of SkyLake > > > Xeon-SP systems raising Hardware Error NMIs upon suspending their > > hotplug ports: > > > > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore > > > .kernel.org%2Flinux-pci%2F20170503180426.GA4058%40otc-nc- > > 03%2F&dat > > > > > a=02%7C01%7Calexander.deucher%40amd.com%7C99ec20b6d4dc410baf800 > > 8d866dd > > > > > e688%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C6373724505855 > > 84491&a > > > > > mp;sdata=EPFyxPA0MDBuAkvH7bbp2wHYnpos8p%2BoZmzlUvvdAek%3D&a > > mp;reserved > > > =0 > > > > > > But if a hotplug port is power manageable by ACPI (as can be detected > > > through presence of Power Resources and corresponding _PS0 and _PS3 > > > methods) then it ought to be safe to suspend it to D3. To this end, > > > amend acpi_pci_bridge_d3() to whitelist such ports for D3. > > > > > > Link: > > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitl > > > ab.freedesktop.org%2Fdrm%2Famd%2F- > > %2Fissues%2F1222&data=02%7C01%7C > > > > > alexander.deucher%40amd.com%7C99ec20b6d4dc410baf8008d866dde688% > > 7C3dd89 > > > > > 61fe4884e608e11a82d994e183d%7C0%7C0%7C637372450585584491&sd > > ata=cMj > > > > > LDIbjp8RQiWX8pgK2bDUH%2B0u3oquy3TqeT9QjZGE%3D&reserved=0 > > > Link: > > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitl > > > ab.freedesktop.org%2Fdrm%2Famd%2F- > > %2Fissues%2F1252&data=02%7C01%7C > > > > > alexander.deucher%40amd.com%7C99ec20b6d4dc410baf8008d866dde688% > > 7C3dd89 > > > > > 61fe4884e608e11a82d994e183d%7C0%7C0%7C637372450585584491&sd > > ata=iP9 > > > > > EqNcM15Dj4Ax%2BE6e2HaMWHEX%2B0IO3cMoi0NXWGzM%3D&reser > > ved=0 > > > Link: > > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitl > > > ab.freedesktop.org%2Fdrm%2Famd%2F- > > %2Fissues%2F1304&data=02%7C01%7C > > > > > alexander.deucher%40amd.com%7C99ec20b6d4dc410baf8008d866dde688% > > 7C3dd89 > > > > > 61fe4884e608e11a82d994e183d%7C0%7C0%7C637372450585584491&sd > > ata=VlT > > > UV2UCH4RvKgTXZcpGOpkjZpfijmPgwtvKx6HRT04%3D&reserved=0 > > > Reported-and-tested-by: Arthur Borsboom <arthurborsboom@xxxxxxxxx> > > > Reported-and-tested-by: matoro <matoro@xxxxxxxxxx> > > > Reported-by: Aaron Zakhrov <aaron.zakhrov@xxxxxxxxx> > > > Reported-by: Michal Rostecki <mrostecki@xxxxxxxx> > > > Reported-by: Shai Coleman <git@xxxxxxxxxxxxxxx> > > > Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx> > > > Cc: stable@xxxxxxxxxxxxxxx > > > Cc: Alex Deucher <alexander.deucher@xxxxxxx> > > > Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > > Cc: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> > > > --- > > > drivers/pci/pci-acpi.c | 10 ++++++++++ > > > 1 file changed, 10 insertions(+) > > > > > > diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index > > > d5869a0..d9aa551 100644 > > > --- a/drivers/pci/pci-acpi.c > > > +++ b/drivers/pci/pci-acpi.c > > > @@ -944,6 +944,16 @@ static bool acpi_pci_bridge_d3(struct pci_dev > > *dev) > > > if (!dev->is_hotplug_bridge) > > > return false; > > > > > > + /* Assume D3 support if the bridge is power-manageable by ACPI. */ > > > + adev = ACPI_COMPANION(&dev->dev); > > > + if (!adev && !pci_dev_is_added(dev)) { > > > + adev = acpi_pci_find_companion(&dev->dev); > > > + ACPI_COMPANION_SET(&dev->dev, adev); > > > + } > > > + > > > + if (adev && acpi_device_power_manageable(adev)) > > > + return true; > > > + > > > /* > > > * Look for a special _DSD property for the root port and if it > > > * is set we know the hierarchy behind it supports D3 just fine. > > > -- > > > > I'm going to apply this patch for 5.10 unless Bjorn would rather route it > > through the PCI tree. > > Any chance we can get this into stable at some point as well? It would be nice to fix the laptops out there in the wild running older kernels. I can mark it for stable, but I'm not sure which releases it should go back to. Thanks!
