1 files changed, 82 insertions, 0 deletions
diff --git a/sys/dev/dpaa/dpaa_common.c b/sys/dev/dpaa/dpaa_common.c
new file mode 100644
index 000000000000..c5055231298b
--- /dev/null
+++ b/sys/dev/dpaa/dpaa_common.c
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2026 Justin Hibbits
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <vm/vm.h>
+#include <vm/pmap.h>
+
+#include <dev/fdt/fdt_common.h>
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+
+#include "dpaa_common.h"
+
+#define	FDT_REG_CELLS	4
+int
+dpaa_map_private_memory(device_t dev, int idx, const char *compat,
+    vm_paddr_t *addrp, size_t *sizep)
+{
+	phandle_t node;
+	pcell_t cells[idx + 1];
+	pcell_t *cell_alloc;
+	int addr_cells, size_cells;
+	uint64_t tmp;
+	u_long align, base, size;
+	vm_paddr_t alloc_base;
+	vm_size_t alloc_range_size;
+	ssize_t alloc_size;
+	void *reserved;
+	int rv;
+
+	node = ofw_bus_get_node(dev);
+	if (OF_getencprop(node, "memory-region", cells, sizeof(cells)) <= 0)
+		return (ENXIO);
+
+	node = OF_node_from_xref(cells[idx]);
+	/* If the memory is already reserved, we just need to return it. */
+	if (fdt_regsize(node, &base, &size) == 0)
+		goto success;
+
+	rv = fdt_addrsize_cells(OF_parent(node), &addr_cells, &size_cells);
+	if (rv != 0)
+		return (rv);
+
+	if (OF_getprop(node, "alignment", &tmp, sizeof(tmp)) <= 0)
+		return (ENXIO);
+
+	align = fdt_data_get(&tmp, addr_cells);
+	if (OF_getprop(node, "size", &tmp, sizeof(tmp)) <= 0)
+		return (ENXIO);
+	size = fdt_data_get(&tmp, size_cells);
+
+	alloc_size =
+	    OF_getencprop_alloc(node, "alloc-ranges", (void **)&cell_alloc);
+	if (alloc_size < 0)
+		return (ENXIO);
+
+	alloc_size /= sizeof(pcell_t);
+	for (int i = 0; i < alloc_size; i += (addr_cells + size_cells)) {
+		alloc_base = fdt_data_get(&cell_alloc[i], addr_cells);
+		alloc_range_size =
+		    fdt_data_get(&cell_alloc[i + addr_cells], size_cells);
+		reserved = contigmalloc(size, M_DEVBUF, M_NOWAIT | M_ZERO,
+		    alloc_base, alloc_base + alloc_range_size, align, 0);
+		if (reserved != NULL)
+			break;
+	}
+	if (reserved == NULL)
+		return (ENOMEM);
+	/* Flush the cache (zeroed memory) because it won't be touched later. */
+	cpu_flush_dcache(reserved, size);
+	base = pmap_kextract((vm_offset_t)reserved);
+
+success:
+	*addrp = base;
+	*sizep = size;
+
+	return (0);
+}