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 <sys/utsname.h>
17 #include "utils.h"
18 #include "flush_utils.h"
19 
20 static inline __u64 load(void *addr)
21 {
22 	__u64 tmp;
23 
24 	asm volatile("ld %0,0(%1)" : "=r"(tmp) : "b"(addr));
25 
26 	return tmp;
27 }
28 
29 void syscall_loop(char *p, unsigned long iterations,
30 		  unsigned long zero_size)
31 {
32 	for (unsigned long i = 0; i < iterations; i++) {
33 		for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
34 			load(p + j);
35 		getppid();
36 	}
37 }
38 
39 void syscall_loop_uaccess(char *p, unsigned long iterations,
40 			  unsigned long zero_size)
41 {
42 	struct utsname utsname;
43 
44 	for (unsigned long i = 0; i < iterations; i++) {
45 		for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
46 			load(p + j);
47 		uname(&utsname);
48 	}
49 }
50 
51 static void sigill_handler(int signr, siginfo_t *info, void *unused)
52 {
53 	static int warned;
54 	ucontext_t *ctx = (ucontext_t *)unused;
55 	unsigned long *pc = &UCONTEXT_NIA(ctx);
56 
57 	/* mtspr 3,RS to check for move to DSCR below */
58 	if ((*((unsigned int *)*pc) & 0xfc1fffff) == 0x7c0303a6) {
59 		if (!warned++)
60 			printf("WARNING: Skipping over dscr setup. Consider running 'ppc64_cpu --dscr=1' manually.\n");
61 		*pc += 4;
62 	} else {
63 		printf("SIGILL at %p\n", pc);
64 		abort();
65 	}
66 }
67 
68 void set_dscr(unsigned long val)
69 {
70 	static int init;
71 	struct sigaction sa;
72 
73 	if (!init) {
74 		memset(&sa, 0, sizeof(sa));
75 		sa.sa_sigaction = sigill_handler;
76 		sa.sa_flags = SA_SIGINFO;
77 		if (sigaction(SIGILL, &sa, NULL))
78 			perror("sigill_handler");
79 		init = 1;
80 	}
81 
82 	asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
83 }
84