1 /* $NetBSD: arm_cpu_topology.c,v 1.9 2024/12/10 11:27:29 jmcneill Exp $ */
2
3 /*
4 * Copyright (c) 2020 Matthew R. Green
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 /* CPU topology support for ARMv7 and ARMv8 systems. */
30
31 #include "opt_multiprocessor.h"
32
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: arm_cpu_topology.c,v 1.9 2024/12/10 11:27:29 jmcneill Exp $");
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/device.h>
40
41 #include <arm/cpu.h>
42 #include <arm/cpu_topology.h>
43 #include <arm/armreg.h>
44
45 #include <prop/proplib.h>
46
47 void
arm_cpu_topology_set(struct cpu_info * const ci,mpidr_t mpidr)48 arm_cpu_topology_set(struct cpu_info * const ci, mpidr_t mpidr)
49 {
50 #ifdef MULTIPROCESSOR
51 uint pkgid, coreid, smtid, numaid;
52 bool use_aff0 = (mpidr & MPIDR_MT) != 0 ||
53 CPU_ID_ORYON_P(ci->ci_midr);
54
55 /* NUMA info comes from firmware tables (ACPI or FDT). */
56 numaid = ci->ci_numa_id;
57
58 if (use_aff0) {
59 pkgid = __SHIFTOUT(mpidr, MPIDR_AFF2);
60 coreid = __SHIFTOUT(mpidr, MPIDR_AFF1);
61 smtid = __SHIFTOUT(mpidr, MPIDR_AFF0);
62 } else {
63 pkgid = __SHIFTOUT(mpidr, MPIDR_AFF1);
64 coreid = __SHIFTOUT(mpidr, MPIDR_AFF0);
65 smtid = 0;
66 }
67 cpu_topology_set(ci, pkgid, coreid, smtid, numaid);
68 #endif /* MULTIPROCESSOR */
69 }
70
71 void
arm_cpu_do_topology(struct cpu_info * const newci)72 arm_cpu_do_topology(struct cpu_info *const newci)
73 {
74 #ifdef MULTIPROCESSOR
75 struct cpu_info *ci;
76 CPU_INFO_ITERATOR cii;
77 prop_dictionary_t dict;
78 uint32_t capacity_dmips_mhz = 0;
79 static uint32_t best_cap = 0;
80
81 dict = device_properties(newci->ci_dev);
82 if (prop_dictionary_get_uint32(dict, "capacity_dmips_mhz",
83 &capacity_dmips_mhz))
84 newci->ci_capacity_dmips_mhz = capacity_dmips_mhz;
85
86 if (newci->ci_capacity_dmips_mhz > best_cap)
87 best_cap = newci->ci_capacity_dmips_mhz;
88
89 /*
90 * CPU_INFO_FOREACH() doesn't always work for this CPU until
91 * mi_cpu_attach() is called and ncpu is bumped, so call it
92 * directly here. This also handles the not-MP case.
93 */
94 cpu_topology_setspeed(newci, newci->ci_capacity_dmips_mhz < best_cap);
95
96 /*
97 * Using saved largest capacity, refresh previous topology info.
98 * It's supposed to be OK to re-set topology.
99 */
100 for (CPU_INFO_FOREACH(cii, ci)) {
101 if (ci == newci)
102 continue;
103 cpu_topology_setspeed(ci,
104 ci->ci_capacity_dmips_mhz < best_cap);
105 }
106 #endif /* MULTIPROCESSOR */
107 }
108