1 // SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
2 /*
3 * Copyright (C) 2019, STMicroelectronics - All Rights Reserved
4 */
5
6 #define LOG_CATEGORY LOGC_ARCH
7
8 #include <common.h>
9 #include <log.h>
10 #include <linux/libfdt.h>
11 #include <asm/sections.h>
12 #include <asm/system.h>
13
14 /*
15 * Force data-section, as .bss will not be valid
16 * when save_boot_params is invoked.
17 */
18 static unsigned long nt_fw_dtb __section(".data");
19
20 /*
21 * Save the FDT address provided by TF-A in r2 at boot time
22 * This function is called from start.S
23 */
save_boot_params(unsigned long r0,unsigned long r1,unsigned long r2,unsigned long r3)24 void save_boot_params(unsigned long r0, unsigned long r1, unsigned long r2,
25 unsigned long r3)
26 {
27 nt_fw_dtb = r2;
28
29 save_boot_params_ret();
30 }
31
32 /*
33 * Use the saved FDT address provided by TF-A at boot time (NT_FW_CONFIG =
34 * Non Trusted Firmware configuration file) when the pointer is valid
35 */
board_fdt_blob_setup(int * err)36 void *board_fdt_blob_setup(int *err)
37 {
38 log_debug("%s: nt_fw_dtb=%lx\n", __func__, nt_fw_dtb);
39
40 *err = 0;
41 /* use external device tree only if address is valid */
42 if (nt_fw_dtb >= STM32_DDR_BASE) {
43 if (fdt_magic(nt_fw_dtb) == FDT_MAGIC)
44 return (void *)nt_fw_dtb;
45 log_debug("%s: DTB not found.\n", __func__);
46 }
47 log_debug("%s: fall back to builtin DTB, %p\n", __func__, &_end);
48
49 return (void *)&_end;
50 }
51