ANDROID: KVM: arm64: iommu: Add idmap trace point

Add a trace point for identity mapping callback.

Bug: 277989609
Bug: 278749606

Change-Id: I918a7a22123f5358b27a77dc4e25bbec371b1efb
Signed-off-by: Mostafa Saleh <smostafa@google.com>

arch/arm64/include/asm/kvm_hypevents.h

@@ -125,4 +125,18 @@ HYP_EVENT(selftest,
 );
 #endif
 
+HYP_EVENT(iommu_idmap,
+	HE_PROTO(u64 from, u64 to, int prot),
+	HE_STRUCT(
+		he_field(u64, from)
+		he_field(u64, to)
+		he_field(int, prot)
+	),
+	HE_ASSIGN(
+		__entry->from = from;
+		__entry->to = to;
+		__entry->prot = prot;
+	),
+	HE_PRINTK("from=0x%llx to=0x%llx prot=0x%x", __entry->from, __entry->to, __entry->prot)
+);
 #endif /* __ARM64_KVM_HYPEVENTS_H_ */

arch/arm64/kvm/hyp/nvhe/iommu/iommu.c

@@ -5,6 +5,7 @@
  * Copyright (C) 2022 Linaro Ltd.
  */
 #include <asm/kvm_hyp.h>
+#include <asm/kvm_hypevents.h>
 
 #include <hyp/adjust_pc.h>
 
@@ -478,6 +479,8 @@ void kvm_iommu_host_stage2_idmap(phys_addr_t start, phys_addr_t end,
 	if (!kvm_iommu_is_ready())
 		return;
 
+	trace_iommu_idmap(start, end, prot);
+
 	domain = __handle_to_domain(KVM_IOMMU_DOMAIN_IDMAP_ID, false);
 
 	kvm_iommu_ops->host_stage2_idmap(domain, start, end, pkvm_to_iommu_prot(prot));