diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c
index 31f4826ab399..2a0ac23cc042 100644
--- a/drivers/resctrl/mpam_devices.c
+++ b/drivers/resctrl/mpam_devices.c
@@ -2349,7 +2349,6 @@ static struct mpam_msc *do_mpam_msc_drv_probe(struct platform_device *pdev)
 	if (err)
 		return ERR_PTR(err);
 
-	mpam_mon_sel_lock_init(msc);
 	msc->id = pdev->id;
 	msc->pdev = pdev;
 	INIT_LIST_HEAD_RCU(&msc->all_msc_list);
@@ -2370,6 +2369,11 @@ static struct mpam_msc *do_mpam_msc_drv_probe(struct platform_device *pdev)
 	else
 		msc->iface = MPAM_IFACE_PCC;
 
+	/* Lock type depends on MSC interface used */
+	err = mpam_mon_sel_lock_init(dev, msc);
+	if (err)
+		return ERR_PTR(err);
+
 	if (msc->iface == MPAM_IFACE_MMIO) {
 		void __iomem *io;
 
diff --git a/drivers/resctrl/mpam_internal.h b/drivers/resctrl/mpam_internal.h
index 09f8168fb4d2..58f7523bc087 100644
--- a/drivers/resctrl/mpam_internal.h
+++ b/drivers/resctrl/mpam_internal.h
@@ -126,6 +126,12 @@ struct mpam_msc {
 	 */
 	raw_spinlock_t		_mon_sel_lock;
 	unsigned long		_mon_sel_flags;
+	/*
+	 * mon_sel_mutex is the mutex version of the _mon_sel_lock above.
+	 * Always use the mpam_mon_sel_lock() helpers when taking the lock,
+	 * as this will select the correct lock type automatically.
+	 */
+	struct mutex		mon_sel_mutex;
 
 	void __iomem		*mapped_hwpage;
 	size_t			mapped_hwpage_sz;
@@ -139,27 +145,50 @@ struct mpam_msc {
 /* Returning false here means accesses to mon_sel must fail and report an error. */
 static inline bool __must_check mpam_mon_sel_lock(struct mpam_msc *msc)
 {
-	/* Locking will require updating to support a firmware backed interface */
-	if (WARN_ON_ONCE(msc->iface != MPAM_IFACE_MMIO))
+	if (msc->iface == MPAM_IFACE_MMIO) {
+		raw_spin_lock_irqsave(&msc->_mon_sel_lock, msc->_mon_sel_flags);
+
+		return true;
+	}
+
+	if (!preemptible())
 		return false;
 
-	raw_spin_lock_irqsave(&msc->_mon_sel_lock, msc->_mon_sel_flags);
+	mutex_lock(&msc->mon_sel_mutex);
+
 	return true;
 }
 
 static inline void mpam_mon_sel_unlock(struct mpam_msc *msc)
 {
-	raw_spin_unlock_irqrestore(&msc->_mon_sel_lock, msc->_mon_sel_flags);
+	if (msc->iface == MPAM_IFACE_MMIO) {
+		raw_spin_unlock_irqrestore(&msc->_mon_sel_lock,
+					   msc->_mon_sel_flags);
+
+		return;
+	}
+
+	mutex_unlock(&msc->mon_sel_mutex);
 }
 
 static inline void mpam_mon_sel_lock_held(struct mpam_msc *msc)
 {
-	lockdep_assert_held_once(&msc->_mon_sel_lock);
+	if (msc->iface == MPAM_IFACE_MMIO)
+		lockdep_assert_held_once(&msc->_mon_sel_lock);
+	else
+		lockdep_assert_held_once(&msc->mon_sel_mutex);
 }
 
-static inline void mpam_mon_sel_lock_init(struct mpam_msc *msc)
+static inline int mpam_mon_sel_lock_init(struct device *dev,
+					 struct mpam_msc *msc)
 {
-	raw_spin_lock_init(&msc->_mon_sel_lock);
+	if (msc->iface == MPAM_IFACE_MMIO) {
+		raw_spin_lock_init(&msc->_mon_sel_lock);
+
+		return 0;
+	}
+
+	return devm_mutex_init(dev, &msc->mon_sel_mutex);
 }
 
 DEFINE_GUARD(mon_sel, struct mpam_msc *,