xref: /linux/tools/perf/arch/powerpc/util/header.c (revision 79d2e1919a2728ef49d938eb20ebd5903c14dfb0)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <sys/types.h>
3 #include <errno.h>
4 #include <unistd.h>
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <linux/stringify.h>
9 #include "header.h"
10 #include "utils_header.h"
11 #include "metricgroup.h"
12 #include <api/fs/fs.h>
13 #include <sys/auxv.h>
14 
15 static bool is_compat_mode(void)
16 {
17 	u64 base_platform = getauxval(AT_BASE_PLATFORM);
18 	u64 platform = getauxval(AT_PLATFORM);
19 
20 	if (!strcmp((char *)platform, (char *)base_platform))
21 		return false;
22 
23 	return true;
24 }
25 
26 int
27 get_cpuid(char *buffer, size_t sz, struct perf_cpu cpu __maybe_unused)
28 {
29 	unsigned long pvr;
30 	int nb;
31 
32 	pvr = mfspr(SPRN_PVR);
33 
34 	nb = scnprintf(buffer, sz, "%lu,%lu$", PVR_VER(pvr), PVR_REV(pvr));
35 
36 	/* look for end marker to ensure the entire data fit */
37 	if (strchr(buffer, '$')) {
38 		buffer[nb-1] = '\0';
39 		return 0;
40 	}
41 	return ENOBUFS;
42 }
43 
44 char *
45 get_cpuid_str(struct perf_cpu cpu __maybe_unused)
46 {
47 	char *bufp;
48 	unsigned long pvr;
49 
50 	/*
51 	 * IBM Power System supports compatible mode. That is
52 	 * Nth generation platform can support previous generation
53 	 * OS in a mode called compatibile mode. For ex. LPAR can be
54 	 * booted in a Power9 mode when the system is a Power10.
55 	 *
56 	 * In the compatible mode, care must be taken when generating
57 	 * PVR value. When read, PVR will be of the AT_BASE_PLATFORM
58 	 * To support generic events, return 0x00ffffff as pvr when
59 	 * booted in compat mode. Based on this pvr value, json will
60 	 * pick events from pmu-events/arch/powerpc/compat
61 	 */
62 	if (!is_compat_mode())
63 		pvr = mfspr(SPRN_PVR);
64 	else
65 		pvr = 0x00ffffff;
66 
67 	if (asprintf(&bufp, "0x%.8lx", pvr) < 0)
68 		bufp = NULL;
69 
70 	return bufp;
71 }
72 
73 int arch_get_runtimeparam(const struct pmu_metric *pm)
74 {
75 	int count;
76 	char path[PATH_MAX] = "/devices/hv_24x7/interface/";
77 
78 	strcat(path, pm->aggr_mode == PerChip ? "sockets" : "coresperchip");
79 	return sysfs__read_int(path, &count) < 0 ? 1 : count;
80 }
81