1// SPDX-License-Identifier: GPL-2.0+
2
3/*
4 * Copyright 2018 IBM Corporation.
5 */
6
7#define __SANE_USERSPACE_TYPES__
8
9#include <sys/types.h>
10#include <stdint.h>
11#include <unistd.h>
12#include <signal.h>
13#include <stdlib.h>
14#include <string.h>
15#include <stdio.h>
16#include "utils.h"
17#include "flush_utils.h"
18
19static inline __u64 load(void *addr)
20{
21	__u64 tmp;
22
23	asm volatile("ld %0,0(%1)" : "=r"(tmp) : "b"(addr));
24
25	return tmp;
26}
27
28void syscall_loop(char *p, unsigned long iterations,
29		  unsigned long zero_size)
30{
31	for (unsigned long i = 0; i < iterations; i++) {
32		for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
33			load(p + j);
34		getppid();
35	}
36}
37
38static void sigill_handler(int signr, siginfo_t *info, void *unused)
39{
40	static int warned;
41	ucontext_t *ctx = (ucontext_t *)unused;
42	unsigned long *pc = &UCONTEXT_NIA(ctx);
43
44	/* mtspr 3,RS to check for move to DSCR below */
45	if ((*((unsigned int *)*pc) & 0xfc1fffff) == 0x7c0303a6) {
46		if (!warned++)
47			printf("WARNING: Skipping over dscr setup. Consider running 'ppc64_cpu --dscr=1' manually.\n");
48		*pc += 4;
49	} else {
50		printf("SIGILL at %p\n", pc);
51		abort();
52	}
53}
54
55void set_dscr(unsigned long val)
56{
57	static int init;
58	struct sigaction sa;
59
60	if (!init) {
61		memset(&sa, 0, sizeof(sa));
62		sa.sa_sigaction = sigill_handler;
63		sa.sa_flags = SA_SIGINFO;
64		if (sigaction(SIGILL, &sa, NULL))
65			perror("sigill_handler");
66		init = 1;
67	}
68
69	asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
70}
71