1/*-
2 * Copyright (c) 2019 Leandro Lupori
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 *
10 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
11 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
12 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
13 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
14 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
15 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
16 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
17 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
18 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
19 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
20 * SUCH DAMAGE.
21 */
22
23static uint32_t cpu_features;
24static uint32_t cpu_features2;
25
26static void
27init_cpu_features(char **env)
28{
29	const Elf_Auxinfo *aux;
30
31	/* Find the auxiliary vector on the stack. */
32	while (*env++ != 0)	/* Skip over environment, and NULL terminator */
33		;
34	aux = (const Elf_Auxinfo *)env;
35
36	/* Digest the auxiliary vector. */
37	for (;  aux->a_type != AT_NULL; aux++) {
38		switch (aux->a_type) {
39		case AT_HWCAP:
40			cpu_features = (uint32_t)aux->a_un.a_val;
41			break;
42		case AT_HWCAP2:
43			cpu_features2 = (uint32_t)aux->a_un.a_val;
44			break;
45		}
46	}
47}
48
49static void
50crt1_handle_rela(const Elf_Rela *r)
51{
52	typedef Elf_Addr (*ifunc_resolver_t)(
53	    uint32_t, uint32_t, uint64_t, uint64_t,
54	    uint64_t, uint64_t, uint64_t, uint64_t);
55	Elf_Addr *ptr, *where, target;
56
57	switch (ELF_R_TYPE(r->r_info)) {
58	case R_PPC_IRELATIVE:
59		ptr = (Elf_Addr *)r->r_addend;
60		where = (Elf_Addr *)r->r_offset;
61		target = ((ifunc_resolver_t)ptr)(cpu_features, cpu_features2,
62		    0, 0, 0, 0, 0, 0);
63		*where = target;
64		break;
65	}
66}
67