Index: sys/arm/arm/gic.c
===================================================================
--- sys/arm/arm/gic.c
+++ sys/arm/arm/gic.c
@@ -64,6 +64,7 @@
 
 #ifdef FDT
 #include <dev/fdt/fdt_intr.h>
+#include <dev/ofw/ofw_bus.h>
 #include <dev/ofw/ofw_bus_subr.h>
 #endif
 
@@ -1049,6 +1050,11 @@
 	struct arm_gicv2m_softc *sc;
 	uint32_t typer;
 	int rid;
+#ifdef FDT
+	phandle_t node;
+	pcell_t cell;
+	int rv;
+#endif
 
 	sc = device_get_softc(dev);
 
@@ -1063,6 +1069,24 @@
 	typer = bus_read_4(sc->sc_mem, GICV2M_MSI_TYPER);
 	sc->sc_spi_start = MSI_TYPER_SPI_BASE(typer);
 	sc->sc_spi_count = MSI_TYPER_SPI_COUNT(typer);
+#ifdef FDT
+	/* Check if SPI data should be overriden by DTS */
+	node = ofw_bus_get_node(dev);
+	rv = OF_getencprop(node, "arm,msi-base-spi", &cell, sizeof(cell));
+	if (rv > 0) {
+		if (bootverbose)
+			device_printf(dev, "overriding SPI_BASE to %ld\n",
+			    (uint64_t)cell);
+		sc->sc_spi_start  = (uint64_t)cell;
+	}
+	rv = OF_getencprop(node, "arm,msi-num-spis", &cell, sizeof(cell));
+	if (rv > 0) {
+		if (bootverbose)
+			device_printf(dev, "overriding NUM_SPIS to %ld\n",
+			    (uint64_t)cell);
+		sc->sc_spi_count  = (uint64_t)cell;
+	}
+#endif
 	sc->sc_spi_end = sc->sc_spi_start + sc->sc_spi_count;
 
 	/* Reserve these interrupts for MSI/MSI-X use */