diff --git a/sys/arm64/arm64/gic_v3_reg.h b/sys/arm64/arm64/gic_v3_reg.h
--- a/sys/arm64/arm64/gic_v3_reg.h
+++ b/sys/arm64/arm64/gic_v3_reg.h
@@ -417,6 +417,8 @@
 #define		GITS_BASER_SIZE_MASK	0xFFUL
 
 #define		GITS_BASER_NUM		8
+/* Size of entries in a level 1 indirect table */
+#define		GITS_INDIRECT_L1_ESIZE	8
 
 #define	GITS_TYPER		(0x0008)
 #define		GITS_TYPER_HCC_SHIFT	24
@@ -433,6 +435,7 @@
 		    ((((x) & GITS_TYPER_ITTES_MASK) >> GITS_TYPER_ITTES_SHIFT) + 1)
 
 #define	GITS_TRANSLATER		(0x10040)
+
 /*
  * LPI related
  */
diff --git a/sys/arm64/arm64/gicv3_its.c b/sys/arm64/arm64/gicv3_its.c
--- a/sys/arm64/arm64/gicv3_its.c
+++ b/sys/arm64/arm64/gicv3_its.c
@@ -1,5 +1,6 @@
 /*-
  * Copyright (c) 2015-2016 The FreeBSD Foundation
+ * Copyright (c) 2023 Arm Ltd
  *
  * This software was developed by Andrew Turner under
  * the sponsorship of the FreeBSD Foundation.
@@ -221,10 +222,16 @@
 /* An ITS private table */
 struct its_ptable {
 	vm_offset_t	ptab_vaddr;
-	/* Size of the L1 table */
+	/* Size of the L1 and L2 tables */
 	size_t		ptab_l1_size;
-	/* Number of L1 entries */
+	size_t		ptab_l2_size;
+	/* Number of L1 and L2 entries */
 	int		ptab_l1_nidents;
+	int		ptab_l2_nidents;
+
+	int		ptab_page_size;
+	int		ptab_share;
+	bool		ptab_indirect;
 };
 
 /* ITS collection description. */
@@ -475,6 +482,23 @@
 	}
 }
 
+static bool
+gicv3_its_table_supports_indirect(struct gicv3_its_softc *sc, int table)
+{
+	uint64_t reg;
+
+	reg = gic_its_read_8(sc, GITS_BASER(table));
+
+	/* Try setting the indirect flag */
+	reg |= GITS_BASER_INDIRECT;
+	gic_its_write_8(sc, GITS_BASER(table), reg);
+
+	/* Read back to check */
+	reg = gic_its_read_8(sc, GITS_BASER(table));
+	return ((reg & GITS_BASER_INDIRECT) != 0);
+}
+
+
 static int
 gicv3_its_table_init(device_t dev, struct gicv3_its_softc *sc)
 {
@@ -482,9 +506,10 @@
 	vm_paddr_t paddr;
 	uint64_t cache, reg, share, tmp, type;
 	size_t its_tbl_size, nitspages, npages;
-	size_t l1_esize, l1_nidents;
+	size_t l1_esize, l2_esize, l1_nidents, l2_nidents;
 	int i, page_size;
 	int devbits;
+	bool indirect;
 
 	if ((sc->sc_its_flags & ITS_FLAGS_ERRATA_CAVIUM_22375) != 0) {
 		/*
@@ -532,6 +557,9 @@
 			return (EINVAL);
 		}
 
+		indirect = false;
+		l2_nidents = 0;
+		l2_esize = 0;
 		switch(type) {
 		case GITS_BASER_TYPE_DEV:
 			if (sc->sc_dev_table_idx != -1)
@@ -540,6 +568,23 @@
 
 			sc->sc_dev_table_idx = i;
 			l1_nidents = (1 << devbits);
+			if ((l1_esize * l1_nidents) > (page_size * 2)) {
+				indirect =
+				    gicv3_its_table_supports_indirect(sc, i);
+				if (indirect) {
+					/*
+					 * Each l1 entry is 8 bytes and points
+					 * to an l2 table of size page_size.
+					 * Calculate how many entries this is
+					 * and use this to find how many
+					 * 8 byte l1 idents we need.
+					 */
+					l2_esize = l1_esize;
+					l2_nidents = page_size / l2_esize;
+					l1_nidents = l1_nidents / l2_nidents;
+					l1_esize = GITS_INDIRECT_L1_ESIZE;
+				}
+			}
 			its_tbl_size = l1_esize * l1_nidents;
 			its_tbl_size = roundup2(its_tbl_size, page_size);
 			break;
@@ -564,6 +609,11 @@
 		sc->sc_its_ptab[i].ptab_vaddr = table;
 		sc->sc_its_ptab[i].ptab_l1_size = its_tbl_size;
 		sc->sc_its_ptab[i].ptab_l1_nidents = l1_nidents;
+		sc->sc_its_ptab[i].ptab_l2_size = page_size;
+		sc->sc_its_ptab[i].ptab_l2_nidents = l2_nidents;
+
+		sc->sc_its_ptab[i].ptab_indirect = indirect;
+		sc->sc_its_ptab[i].ptab_page_size = page_size;
 
 		paddr = vtophys(table);
 
@@ -578,6 +628,7 @@
 			    GITS_BASER_SIZE_MASK);
 			/* Set the new values */
 			reg |= GITS_BASER_VALID |
+			    (indirect ? GITS_BASER_INDIRECT : 0) |
 			    (cache << GITS_BASER_CACHE_SHIFT) |
 			    (type << GITS_BASER_TYPE_SHIFT) |
 			    paddr | (share << GITS_BASER_SHARE_SHIFT) |
@@ -618,6 +669,7 @@
 				return (ENXIO);
 			}
 
+			sc->sc_its_ptab[i].ptab_share = share;
 			/* We should have made all needed changes */
 			break;
 		}
@@ -1218,6 +1270,10 @@
 its_device_alloc(struct gicv3_its_softc *sc, int devid)
 {
 	struct its_ptable *ptable;
+	vm_offset_t l2_table;
+	uint64_t *table;
+	uint32_t index;
+	bool shareable;
 
 	/* No device table */
 	if (sc->sc_dev_table_idx < 0) {
@@ -1228,7 +1284,39 @@
 
 	ptable = &sc->sc_its_ptab[sc->sc_dev_table_idx];
 	/* Check the devid is within the table limit */
-	return (devid < ptable->ptab_l1_nidents);
+	if (!ptable->ptab_indirect) {
+		return (devid < ptable->ptab_l1_nidents);
+	}
+
+	/* Check the devid is within the allocated range */
+	index = devid / ptable->ptab_l2_nidents;
+	if (index >= ptable->ptab_l1_nidents)
+		return (false);
+
+	table = (uint64_t *)ptable->ptab_vaddr;
+	/* We have an second level table */
+	if ((table[index] & GITS_BASER_VALID) != 0)
+		return (true);
+
+	shareable = true;
+	if ((ptable->ptab_share & GITS_BASER_SHARE_MASK) == GITS_BASER_SHARE_NS)
+		shareable = false;
+
+	l2_table = (vm_offset_t)contigmalloc_domainset(ptable->ptab_l2_size,
+	    M_GICV3_ITS, sc->sc_ds, M_WAITOK | M_ZERO, 0, (1ul << 48) - 1,
+	    ptable->ptab_page_size, 0);
+
+	if (!shareable)
+		cpu_dcache_wb_range((vm_offset_t)l2_table,
+		    ptable->ptab_l2_size);
+
+	table[index] = vtophys(l2_table) | GITS_BASER_VALID;
+	if (!shareable)
+		cpu_dcache_wb_range((vm_offset_t)&table[index],
+		    sizeof(table[index]));
+
+	dsb(sy);
+	return (true);
 }
 
 static struct its_dev *