diff --git a/arch/x86/events/amd/iommu.c b/arch/x86/events/amd/iommu.c
index 10f67d39cac5..88fbc8001460 100644
--- a/arch/x86/events/amd/iommu.c
+++ b/arch/x86/events/amd/iommu.c
@@ -248,49 +248,45 @@ static int perf_iommu_event_init(struct perf_event *event)
 
 static void perf_iommu_enable_event(struct perf_event *ev)
 {
+	struct amd_iommu *iommu = get_amd_iommu(0);
 	u8 csource = _GET_CSOURCE(ev);
 	u16 devid = _GET_DEVID(ev);
+	u8 bank = _GET_BANK(ev);
+	u8 cntr = _GET_CNTR(ev);
 	u64 reg = 0ULL;
 
 	reg = csource;
-	amd_iommu_pc_get_set_reg_val(devid,
-			_GET_BANK(ev), _GET_CNTR(ev) ,
-			 IOMMU_PC_COUNTER_SRC_REG, &reg, true);
+	amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_COUNTER_SRC_REG, &reg);
 
 	reg = devid | (_GET_DEVID_MASK(ev) << 32);
 	if (reg)
 		reg |= BIT(31);
-	amd_iommu_pc_get_set_reg_val(devid,
-			_GET_BANK(ev), _GET_CNTR(ev) ,
-			 IOMMU_PC_DEVID_MATCH_REG, &reg, true);
+	amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_DEVID_MATCH_REG, &reg);
 
 	reg = _GET_PASID(ev) | (_GET_PASID_MASK(ev) << 32);
 	if (reg)
 		reg |= BIT(31);
-	amd_iommu_pc_get_set_reg_val(devid,
-			_GET_BANK(ev), _GET_CNTR(ev) ,
-			 IOMMU_PC_PASID_MATCH_REG, &reg, true);
+	amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_PASID_MATCH_REG, &reg);
 
 	reg = _GET_DOMID(ev) | (_GET_DOMID_MASK(ev) << 32);
 	if (reg)
 		reg |= BIT(31);
-	amd_iommu_pc_get_set_reg_val(devid,
-			_GET_BANK(ev), _GET_CNTR(ev) ,
-			 IOMMU_PC_DOMID_MATCH_REG, &reg, true);
+	amd_iommu_pc_set_reg(iommu, bank, cntr, IOMMU_PC_DOMID_MATCH_REG, &reg);
 }
 
 static void perf_iommu_disable_event(struct perf_event *event)
 {
+	struct amd_iommu *iommu = get_amd_iommu(0);
 	u64 reg = 0ULL;
 
-	amd_iommu_pc_get_set_reg_val(_GET_DEVID(event),
-			_GET_BANK(event), _GET_CNTR(event),
-			IOMMU_PC_COUNTER_SRC_REG, &reg, true);
+	amd_iommu_pc_set_reg(iommu, _GET_BANK(event), _GET_CNTR(event),
+			     IOMMU_PC_COUNTER_SRC_REG, &reg);
 }
 
 static void perf_iommu_start(struct perf_event *event, int flags)
 {
 	struct hw_perf_event *hwc = &event->hw;
+	struct amd_iommu *iommu = get_amd_iommu(0);
 
 	if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
 		return;
@@ -300,9 +296,8 @@ static void perf_iommu_start(struct perf_event *event, int flags)
 
 	if (flags & PERF_EF_RELOAD) {
 		u64 prev_raw_count =  local64_read(&hwc->prev_count);
-		amd_iommu_pc_get_set_reg_val(_GET_DEVID(event),
-				_GET_BANK(event), _GET_CNTR(event),
-				IOMMU_PC_COUNTER_REG, &prev_raw_count, true);
+		amd_iommu_pc_set_reg(iommu, _GET_BANK(event), _GET_CNTR(event),
+				     IOMMU_PC_COUNTER_REG, &prev_raw_count);
 	}
 
 	perf_iommu_enable_event(event);
@@ -314,10 +309,11 @@ static void perf_iommu_read(struct perf_event *event)
 {
 	u64 count, prev, delta;
 	struct hw_perf_event *hwc = &event->hw;
+	struct amd_iommu *iommu = get_amd_iommu(0);
 
-	amd_iommu_pc_get_set_reg_val(_GET_DEVID(event),
-				_GET_BANK(event), _GET_CNTR(event),
-				IOMMU_PC_COUNTER_REG, &count, false);
+	if (amd_iommu_pc_get_reg(iommu, _GET_BANK(event), _GET_CNTR(event),
+				 IOMMU_PC_COUNTER_REG, &count))
+		return;
 
 	/* IOMMU pc counter register is only 48 bits */
 	count &= GENMASK_ULL(47, 0);
diff --git a/arch/x86/events/amd/iommu.h b/arch/x86/events/amd/iommu.h
index b775107c221e..62e0702c4374 100644
--- a/arch/x86/events/amd/iommu.h
+++ b/arch/x86/events/amd/iommu.h
@@ -24,6 +24,8 @@
 #define PC_MAX_SPEC_BNKS			64
 #define PC_MAX_SPEC_CNTRS			16
 
+struct amd_iommu;
+
 /* amd_iommu_init.c external support functions */
 extern int amd_iommu_get_num_iommus(void);
 
@@ -33,8 +35,11 @@ extern u8 amd_iommu_pc_get_max_banks(unsigned int idx);
 
 extern u8 amd_iommu_pc_get_max_counters(unsigned int idx);
 
-extern int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr,
-			u8 fxn, u64 *value, bool is_write);
+extern int amd_iommu_pc_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr,
+				u8 fxn, u64 *value);
+
+extern int amd_iommu_pc_get_reg(struct amd_iommu *iommu, u8 bank, u8 cntr,
+				u8 fxn, u64 *value);
 
 extern struct amd_iommu *get_amd_iommu(int idx);
 
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 8fdf109e6109..5a11328f4d98 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -256,10 +256,6 @@ static int amd_iommu_enable_interrupts(void);
 static int __init iommu_go_to_state(enum iommu_init_state state);
 static void init_device_table_dma(void);
 
-static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
-				    u8 bank, u8 cntr, u8 fxn,
-				    u64 *value, bool is_write);
-
 static inline void update_last_devid(u16 devid)
 {
 	if (devid > amd_iommu_last_bdf)
@@ -1484,6 +1480,8 @@ static int __init init_iommu_all(struct acpi_table_header *table)
 	return 0;
 }
 
+static int iommu_pc_get_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr,
+				u8 fxn, u64 *value, bool is_write);
 
 static void init_iommu_perf_ctr(struct amd_iommu *iommu)
 {
@@ -1495,8 +1493,8 @@ static void init_iommu_perf_ctr(struct amd_iommu *iommu)
 	amd_iommu_pc_present = true;
 
 	/* Check if the performance counters can be written to */
-	if ((0 != iommu_pc_get_set_reg_val(iommu, 0, 0, 0, &val, true)) ||
-	    (0 != iommu_pc_get_set_reg_val(iommu, 0, 0, 0, &val2, false)) ||
+	if ((iommu_pc_get_set_reg(iommu, 0, 0, 0, &val, true)) ||
+	    (iommu_pc_get_set_reg(iommu, 0, 0, 0, &val2, false)) ||
 	    (val != val2)) {
 		pr_err("AMD-Vi: Unable to write to IOMMU perf counter.\n");
 		amd_iommu_pc_present = false;
@@ -2765,15 +2763,18 @@ u8 amd_iommu_pc_get_max_counters(unsigned int idx)
 }
 EXPORT_SYMBOL(amd_iommu_pc_get_max_counters);
 
-static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
-				    u8 bank, u8 cntr, u8 fxn,
-				    u64 *value, bool is_write)
+static int iommu_pc_get_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr,
+				u8 fxn, u64 *value, bool is_write)
 {
 	u32 offset;
 	u32 max_offset_lim;
 
+	/* Make sure the IOMMU PC resource is available */
+	if (!amd_iommu_pc_present)
+		return -ENODEV;
+
 	/* Check for valid iommu and pc register indexing */
-	if (WARN_ON((fxn > 0x28) || (fxn & 7)))
+	if (WARN_ON(!iommu || (fxn > 0x28) || (fxn & 7)))
 		return -ENODEV;
 
 	offset = (u32)(((0x40 | bank) << 12) | (cntr << 8) | fxn);
@@ -2799,17 +2800,21 @@ static int iommu_pc_get_set_reg_val(struct amd_iommu *iommu,
 
 	return 0;
 }
-EXPORT_SYMBOL(amd_iommu_pc_get_set_reg_val);
 
-int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
-				    u64 *value, bool is_write)
+int amd_iommu_pc_get_reg(struct amd_iommu *iommu, u8 bank, u8 cntr, u8 fxn, u64 *value)
 {
-	struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
+	if (!iommu)
+		return -EINVAL;
 
-	/* Make sure the IOMMU PC resource is available */
-	if (!amd_iommu_pc_present || iommu == NULL)
-		return -ENODEV;
-
-	return iommu_pc_get_set_reg_val(iommu, bank, cntr, fxn,
-					value, is_write);
+	return iommu_pc_get_set_reg(iommu, bank, cntr, fxn, value, false);
 }
+EXPORT_SYMBOL(amd_iommu_pc_get_reg);
+
+int amd_iommu_pc_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr, u8 fxn, u64 *value)
+{
+	if (!iommu)
+		return -EINVAL;
+
+	return iommu_pc_get_set_reg(iommu, bank, cntr, fxn, value, true);
+}
+EXPORT_SYMBOL(amd_iommu_pc_set_reg);
diff --git a/drivers/iommu/amd_iommu_proto.h b/drivers/iommu/amd_iommu_proto.h
index cd2257e20c3f..466260f8a1df 100644
--- a/drivers/iommu/amd_iommu_proto.h
+++ b/drivers/iommu/amd_iommu_proto.h
@@ -57,11 +57,6 @@ extern int amd_iommu_domain_set_gcr3(struct iommu_domain *dom, int pasid,
 extern int amd_iommu_domain_clear_gcr3(struct iommu_domain *dom, int pasid);
 extern struct iommu_domain *amd_iommu_get_v2_domain(struct pci_dev *pdev);
 
-/* IOMMU Performance Counter functions */
-extern bool amd_iommu_pc_supported(void);
-extern int amd_iommu_pc_get_set_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
-				    u64 *value, bool is_write);
-
 #ifdef CONFIG_IRQ_REMAP
 extern int amd_iommu_create_irq_domain(struct amd_iommu *iommu);
 #else