On Mon, Oct 09, 2023 at 01:46:43PM -0500, Mario Limonciello wrote: > On some OEM systems, adding a W7900 dGPU triggers RAS errors and hangs > at a black screen on startup. This issue occurs only if `ucsi_acpi` has > loaded before `amdgpu` has loaded. The reason for this failure is that > `amdgpu` uses power_supply_is_system_supplied() to determine if running > on AC or DC power at startup. If this value is reported incorrectly the > dGPU will also be programmed incorrectly and trigger errors. > > power_supply_is_system_supplied() reports the wrong value because UCSI > power supplies provided as part of the system don't properly report the > scope as "DEVICE" scope (not powering the system). > > In order to fix this issue check the capabilities reported from the UCSI > power supply to ensure that it supports charging a battery and that it can > be powered by AC. Mark the scope accordingly. > > Cc: stable@xxxxxxxxxxxxxxx > Fixes: a7fbfd44c020 ("usb: typec: ucsi: Mark dGPUs as DEVICE scope") > Link: https://www.intel.com/content/www/us/en/products/docs/io/universal-serial-bus/usb-type-c-ucsi-spec.html p28 > Reviewed-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx> > Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> > --- > Cc: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> > Cc: Alex Deucher <Alexander.Deucher@xxxxxxx>> > Cc: Richard Gong <Richard.Gong@xxxxxxx> > > v2->v3: > * Pick up tag > * Add missing stable tag > * Drop patch 2, we'll just avoid upstreaming it. > --- > drivers/usb/typec/ucsi/psy.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/usb/typec/ucsi/psy.c b/drivers/usb/typec/ucsi/psy.c > index 384b42267f1f..b35c6e07911e 100644 > --- a/drivers/usb/typec/ucsi/psy.c > +++ b/drivers/usb/typec/ucsi/psy.c > @@ -37,6 +37,15 @@ static int ucsi_psy_get_scope(struct ucsi_connector *con, > struct device *dev = con->ucsi->dev; > > device_property_read_u8(dev, "scope", &scope); > + if (scope == POWER_SUPPLY_SCOPE_UNKNOWN) { > + u32 mask = UCSI_CAP_ATTR_POWER_AC_SUPPLY | > + UCSI_CAP_ATTR_BATTERY_CHARGING; > + > + if (con->ucsi->cap.attributes & mask) > + scope = POWER_SUPPLY_SCOPE_SYSTEM; > + else > + scope = POWER_SUPPLY_SCOPE_DEVICE; > + } > val->intval = scope; > return 0; > } > -- > 2.34.1 -- heikki