xref: /freebsd/sys/dev/dpaa/dpaa_common.c (revision bac7bd5038e09d12dfdbf79a87b25443e02d0ba9)
1 /*
2  * Copyright (c) 2026 Justin Hibbits
3  *
4  * SPDX-License-Identifier: BSD-2-Clause
5  */
6 
7 #include <sys/param.h>
8 #include <sys/systm.h>
9 #include <vm/vm.h>
10 #include <vm/pmap.h>
11 
12 #include <dev/fdt/fdt_common.h>
13 #include <dev/ofw/ofw_bus.h>
14 #include <dev/ofw/ofw_bus_subr.h>
15 
16 #include "dpaa_common.h"
17 
18 #define	FDT_REG_CELLS	4
19 int
20 dpaa_map_private_memory(device_t dev, int idx, const char *compat,
21     vm_paddr_t *addrp, size_t *sizep)
22 {
23 	phandle_t node;
24 	pcell_t cells[idx + 1];
25 	pcell_t *cell_alloc;
26 	int addr_cells, size_cells;
27 	uint64_t tmp;
28 	u_long align, base, size;
29 	vm_paddr_t alloc_base;
30 	vm_size_t alloc_range_size;
31 	ssize_t alloc_size;
32 	void *reserved;
33 	int rv;
34 
35 	node = ofw_bus_get_node(dev);
36 	if (OF_getencprop(node, "memory-region", cells, sizeof(cells)) <= 0)
37 		return (ENXIO);
38 
39 	node = OF_node_from_xref(cells[idx]);
40 	/* If the memory is already reserved, we just need to return it. */
41 	if (fdt_regsize(node, &base, &size) == 0)
42 		goto success;
43 
44 	rv = fdt_addrsize_cells(OF_parent(node), &addr_cells, &size_cells);
45 	if (rv != 0)
46 		return (rv);
47 
48 	if (OF_getprop(node, "alignment", &tmp, sizeof(tmp)) <= 0)
49 		return (ENXIO);
50 
51 	align = fdt_data_get(&tmp, addr_cells);
52 	if (OF_getprop(node, "size", &tmp, sizeof(tmp)) <= 0)
53 		return (ENXIO);
54 	size = fdt_data_get(&tmp, size_cells);
55 
56 	alloc_size =
57 	    OF_getencprop_alloc(node, "alloc-ranges", (void **)&cell_alloc);
58 	if (alloc_size < 0)
59 		return (ENXIO);
60 
61 	alloc_size /= sizeof(pcell_t);
62 	for (int i = 0; i < alloc_size; i += (addr_cells + size_cells)) {
63 		alloc_base = fdt_data_get(&cell_alloc[i], addr_cells);
64 		alloc_range_size =
65 		    fdt_data_get(&cell_alloc[i + addr_cells], size_cells);
66 		reserved = contigmalloc(size, M_DEVBUF, M_NOWAIT | M_ZERO,
67 		    alloc_base, alloc_base + alloc_range_size, align, 0);
68 		if (reserved != NULL)
69 			break;
70 	}
71 	if (reserved == NULL)
72 		return (ENOMEM);
73 	/* Flush the cache (zeroed memory) because it won't be touched later. */
74 	cpu_flush_dcache(reserved, size);
75 	base = pmap_kextract((vm_offset_t)reserved);
76 
77 success:
78 	*addrp = base;
79 	*sizep = size;
80 
81 	return (0);
82 }
83