1 /*
2  * Copyright (c) 2020, NVIDIA Corporation. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <stdint.h>
8 
9 #include <arch_helpers.h>
10 #include <lib/mmio.h>
11 #include <plat/common/platform.h>
12 #include <platform_def.h>
13 
plat_get_stack_protector_canary(void)14 u_register_t plat_get_stack_protector_canary(void)
15 {
16 	u_register_t seed;
17 
18 	/*
19 	 * Ideally, a random number should be returned instead. As the
20 	 * platform does not have any random number generator, this is
21 	 * better than nothing, but not really secure.
22 	 */
23 	seed = mmio_read_32(TEGRA_MISC_BASE + HARDWARE_REVISION_OFFSET);
24 	seed <<= 32;
25 	seed |= mmio_read_32(TEGRA_TMRUS_BASE);
26 
27 	return seed ^ read_cntpct_el0();
28 }
29