[PATCH AUTOSEL 5.15 001/109] iommu/vt-d: Add RPLS to quirk list to skip TE disabling

Sasha Levin
2022-05-30T14:04:20Z

From: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@intel.com>

[ Upstream commit 0a967f5bfd9134b89681cae58deb222e20840e76 ]

The VT-d spec requires (10.4.4 Global Command Register, TE
field) that:

Hardware implementations supporting DMA draining must drain
any in-flight DMA read/write requests queued within the
Root-Complex before completing the translation enable
command and reflecting the status of the command through
the TES field in the Global Status register.

Unfortunately, some integrated graphic devices fail to do
so after some kind of power state transition. As the
result, the system might stuck in iommu_disable_translati
on(), waiting for the completion of TE transition.

This adds RPLS to a quirk list for those devices and skips
TE disabling if the qurik hits.

Link: https://gitlab.freedesktop.org/drm/intel/-/issues/4898
Tested-by: Raviteja Goud Talla <ravitejax.goud.talla@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Tejas Upadhyay <tejaskumarx.surendrakumar.upadhyay@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220302043256.191529-1-tejaskumarx.surendrakumar.upadhyay@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/intel/iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 91a5c75966f3..a1ffb3d6d901 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5728,7 +5728,7 @@ static void quirk_igfx_skip_te_disable(struct pci_dev *dev)
ver = (dev->device >> 8) & 0xff;
if (ver != 0x45 && ver != 0x46 && ver != 0x4c &&
ver != 0x4e && ver != 0x8a && ver != 0x98 &&
- ver != 0x9a)
+ ver != 0x9a && ver != 0xa7)
return;

if (risky_device(dev))
--
2.35.1