1 /*
2 * Copyright (c) 2023 Carlo Caione, <ccaione@baylibre.com>
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/kernel.h>
8 #include <zephyr/mem_mgmt/mem_attr.h>
9
10 #define _BUILD_MEM_ATTR_REGION(node_id) \
11 { \
12 .dt_name = DT_NODE_FULL_NAME(node_id), \
13 .dt_addr = DT_REG_ADDR(node_id), \
14 .dt_size = DT_REG_SIZE(node_id), \
15 .dt_attr = DT_PROP(node_id, zephyr_memory_attr), \
16 },
17
18 static const struct mem_attr_region_t mem_attr_region[] = {
19 DT_MEMORY_ATTR_FOREACH_STATUS_OKAY_NODE(_BUILD_MEM_ATTR_REGION)
20 };
21
mem_attr_get_regions(const struct mem_attr_region_t ** region)22 size_t mem_attr_get_regions(const struct mem_attr_region_t **region)
23 {
24 *region = mem_attr_region;
25
26 return ARRAY_SIZE(mem_attr_region);
27 }
28
mem_attr_check_buf(void * v_addr,size_t size,uint32_t attr)29 int mem_attr_check_buf(void *v_addr, size_t size, uint32_t attr)
30 {
31 uintptr_t addr = (uintptr_t) v_addr;
32
33 /*
34 * If MMU is enabled the address of the buffer is a virtual address
35 * while the addresses in the DT are physical addresses. Given that we
36 * have no way of knowing whether a mapping exists, we simply bail out.
37 */
38 if (IS_ENABLED(CONFIG_MMU)) {
39 return -ENOSYS;
40 }
41
42 if (size == 0) {
43 return -ENOTSUP;
44 }
45
46 for (size_t idx = 0; idx < ARRAY_SIZE(mem_attr_region); idx++) {
47 const struct mem_attr_region_t *region = &mem_attr_region[idx];
48 size_t region_end = region->dt_addr + region->dt_size;
49
50 /* Check if the buffer is in the region */
51 if ((addr >= region->dt_addr) && (addr < region_end)) {
52 /* Check if the buffer is entirely contained in the region */
53 if ((addr + size) <= region_end) {
54 /* check if the attribute is correct */
55 return (region->dt_attr & attr) == attr ? 0 : -EINVAL;
56 }
57 return -ENOSPC;
58 }
59 }
60 return -ENOBUFS;
61 }
62
