iommu/vt-d: Remove LPIG from page group response descriptor

Bit 66 in the page group response descriptor used to be the LPIG (Last
Page in Group), but it was marked as Reserved since Specification 4.0.
Remove programming on this bit to make it consistent with the latest
specification.

Existing hardware all treats bit 66 of the page group response descriptor
as "ignored", therefore this change doesn't break any existing hardware.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20250901053943.1708490-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Author: LuBaolu

drivers/iommu/intel/iommu.h

@@ -460,7 +460,6 @@ enum {
 #define QI_PGRP_PASID(pasid)	(((u64)(pasid)) << 32)
 
 /* Page group response descriptor QW1 */
-#define QI_PGRP_LPIG(x)		(((u64)(x)) << 2)
 #define QI_PGRP_IDX(idx)	(((u64)(idx)) << 3)
 
 

drivers/iommu/intel/prq.c

@@ -151,8 +151,7 @@ static void handle_bad_prq_event(struct intel_iommu *iommu,
 			QI_PGRP_PASID_P(req->pasid_present) |
 			QI_PGRP_RESP_CODE(result) |
 			QI_PGRP_RESP_TYPE;
-	desc.qw1 = QI_PGRP_IDX(req->prg_index) |
-			QI_PGRP_LPIG(req->lpig);
+	desc.qw1 = QI_PGRP_IDX(req->prg_index);
 
 	qi_submit_sync(iommu, &desc, 1, 0);
 }
@@ -379,19 +378,17 @@ void intel_iommu_page_response(struct device *dev, struct iopf_fault *evt,
 	struct iommu_fault_page_request *prm;
 	struct qi_desc desc;
 	bool pasid_present;
-	bool last_page;
 	u16 sid;
 
 	prm = &evt->fault.prm;
 	sid = PCI_DEVID(bus, devfn);
 	pasid_present = prm->flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
-	last_page = prm->flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE;
 
 	desc.qw0 = QI_PGRP_PASID(prm->pasid) | QI_PGRP_DID(sid) |
 			QI_PGRP_PASID_P(pasid_present) |
 			QI_PGRP_RESP_CODE(msg->code) |
 			QI_PGRP_RESP_TYPE;
-	desc.qw1 = QI_PGRP_IDX(prm->grpid) | QI_PGRP_LPIG(last_page);
+	desc.qw1 = QI_PGRP_IDX(prm->grpid);
 	desc.qw2 = 0;
 	desc.qw3 = 0;