[PATCH 5/7] iommu/vt-d: Add MTL to quirk list to skip TE disabling

Lu Baolu
2023-11-22T03:30:50Z

From: "Abdul Halim, Mohd Syazwan" <mohd.syazwan.abdul.halim@intel.com>

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 switching
address translation on or off 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_translation(), waiting for the completion of TE transition.

Add MTL to the quirk list for those devices and skips TE disabling if the
qurik hits.

Fixes: b1012ca8dc4f ("iommu/vt-d: Skip TE disabling on quirky gfx dedicated iommu")
Cc: stable@vger.kernel.org
Signed-off-by: Abdul Halim, Mohd Syazwan <mohd.syazwan.abdul.halim@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20231116022324.30120-1-baolu.lu@linux.intel.com
---
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 4c257ccf9dc3..68f121c28fbf 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5077,7 +5077,7 @@ 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 != 0xa7)
+ ver != 0x9a && ver != 0xa7 && ver != 0x7d)
return;

if (risky_device(dev))
--
2.34.1