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1/*
2 * Copyright (C) 2012 Regents of the University of California
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 */
13
14#include <linux/init.h>
15#include <linux/seq_file.h>
16#include <linux/of.h>
17
18/* Return -1 if not a valid hart */
19int riscv_of_processor_hart(struct device_node *node)
20{
21 const char *isa, *status;
22 u32 hart;
23
24 if (!of_device_is_compatible(node, "riscv")) {
25 pr_warn("Found incompatible CPU\n");
26 return -(ENODEV);
27 }
28
29 if (of_property_read_u32(node, "reg", &hart)) {
30 pr_warn("Found CPU without hart ID\n");
31 return -(ENODEV);
32 }
33 if (hart >= NR_CPUS) {
34 pr_info("Found hart ID %d, which is above NR_CPUs. Disabling this hart\n", hart);
35 return -(ENODEV);
36 }
37
38 if (of_property_read_string(node, "status", &status)) {
39 pr_warn("CPU with hartid=%d has no \"status\" property\n", hart);
40 return -(ENODEV);
41 }
42 if (strcmp(status, "okay")) {
43 pr_info("CPU with hartid=%d has a non-okay status of \"%s\"\n", hart, status);
44 return -(ENODEV);
45 }
46
47 if (of_property_read_string(node, "riscv,isa", &isa)) {
48 pr_warn("CPU with hartid=%d has no \"riscv,isa\" property\n", hart);
49 return -(ENODEV);
50 }
51 if (isa[0] != 'r' || isa[1] != 'v') {
52 pr_warn("CPU with hartid=%d has an invalid ISA of \"%s\"\n", hart, isa);
53 return -(ENODEV);
54 }
55
56 return hart;
57}
58
59#ifdef CONFIG_PROC_FS
60
61static void *c_start(struct seq_file *m, loff_t *pos)
62{
63 *pos = cpumask_next(*pos - 1, cpu_online_mask);
64 if ((*pos) < nr_cpu_ids)
65 return (void *)(uintptr_t)(1 + *pos);
66 return NULL;
67}
68
69static void *c_next(struct seq_file *m, void *v, loff_t *pos)
70{
71 (*pos)++;
72 return c_start(m, pos);
73}
74
75static void c_stop(struct seq_file *m, void *v)
76{
77}
78
79static int c_show(struct seq_file *m, void *v)
80{
81 unsigned long hart_id = (unsigned long)v - 1;
82 struct device_node *node = of_get_cpu_node(hart_id, NULL);
83 const char *compat, *isa, *mmu;
84
85 seq_printf(m, "hart\t: %lu\n", hart_id);
86 if (!of_property_read_string(node, "riscv,isa", &isa)
87 && isa[0] == 'r'
88 && isa[1] == 'v')
89 seq_printf(m, "isa\t: %s\n", isa);
90 if (!of_property_read_string(node, "mmu-type", &mmu)
91 && !strncmp(mmu, "riscv,", 6))
92 seq_printf(m, "mmu\t: %s\n", mmu+6);
93 if (!of_property_read_string(node, "compatible", &compat)
94 && strcmp(compat, "riscv"))
95 seq_printf(m, "uarch\t: %s\n", compat);
96 seq_puts(m, "\n");
97
98 return 0;
99}
100
101const struct seq_operations cpuinfo_op = {
102 .start = c_start,
103 .next = c_next,
104 .stop = c_stop,
105 .show = c_show
106};
107
108#endif /* CONFIG_PROC_FS */
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2012 Regents of the University of California
4 */
5
6#include <linux/init.h>
7#include <linux/seq_file.h>
8#include <linux/of.h>
9#include <asm/smp.h>
10
11/*
12 * Returns the hart ID of the given device tree node, or -ENODEV if the node
13 * isn't an enabled and valid RISC-V hart node.
14 */
15int riscv_of_processor_hartid(struct device_node *node)
16{
17 const char *isa;
18 u32 hart;
19
20 if (!of_device_is_compatible(node, "riscv")) {
21 pr_warn("Found incompatible CPU\n");
22 return -ENODEV;
23 }
24
25 if (of_property_read_u32(node, "reg", &hart)) {
26 pr_warn("Found CPU without hart ID\n");
27 return -ENODEV;
28 }
29
30 if (!of_device_is_available(node)) {
31 pr_info("CPU with hartid=%d is not available\n", hart);
32 return -ENODEV;
33 }
34
35 if (of_property_read_string(node, "riscv,isa", &isa)) {
36 pr_warn("CPU with hartid=%d has no \"riscv,isa\" property\n", hart);
37 return -ENODEV;
38 }
39 if (isa[0] != 'r' || isa[1] != 'v') {
40 pr_warn("CPU with hartid=%d has an invalid ISA of \"%s\"\n", hart, isa);
41 return -ENODEV;
42 }
43
44 return hart;
45}
46
47/*
48 * Find hart ID of the CPU DT node under which given DT node falls.
49 *
50 * To achieve this, we walk up the DT tree until we find an active
51 * RISC-V core (HART) node and extract the cpuid from it.
52 */
53int riscv_of_parent_hartid(struct device_node *node)
54{
55 for (; node; node = node->parent) {
56 if (of_device_is_compatible(node, "riscv"))
57 return riscv_of_processor_hartid(node);
58 }
59
60 return -1;
61}
62
63#ifdef CONFIG_PROC_FS
64
65static void print_isa(struct seq_file *f, const char *isa)
66{
67 /* Print the entire ISA as it is */
68 seq_puts(f, "isa\t\t: ");
69 seq_write(f, isa, strlen(isa));
70 seq_puts(f, "\n");
71}
72
73static void print_mmu(struct seq_file *f, const char *mmu_type)
74{
75#if defined(CONFIG_32BIT)
76 if (strcmp(mmu_type, "riscv,sv32") != 0)
77 return;
78#elif defined(CONFIG_64BIT)
79 if (strcmp(mmu_type, "riscv,sv39") != 0 &&
80 strcmp(mmu_type, "riscv,sv48") != 0)
81 return;
82#endif
83
84 seq_printf(f, "mmu\t\t: %s\n", mmu_type+6);
85}
86
87static void *c_start(struct seq_file *m, loff_t *pos)
88{
89 *pos = cpumask_next(*pos - 1, cpu_online_mask);
90 if ((*pos) < nr_cpu_ids)
91 return (void *)(uintptr_t)(1 + *pos);
92 return NULL;
93}
94
95static void *c_next(struct seq_file *m, void *v, loff_t *pos)
96{
97 (*pos)++;
98 return c_start(m, pos);
99}
100
101static void c_stop(struct seq_file *m, void *v)
102{
103}
104
105static int c_show(struct seq_file *m, void *v)
106{
107 unsigned long cpu_id = (unsigned long)v - 1;
108 struct device_node *node = of_get_cpu_node(cpu_id, NULL);
109 const char *compat, *isa, *mmu;
110
111 seq_printf(m, "processor\t: %lu\n", cpu_id);
112 seq_printf(m, "hart\t\t: %lu\n", cpuid_to_hartid_map(cpu_id));
113 if (!of_property_read_string(node, "riscv,isa", &isa))
114 print_isa(m, isa);
115 if (!of_property_read_string(node, "mmu-type", &mmu))
116 print_mmu(m, mmu);
117 if (!of_property_read_string(node, "compatible", &compat)
118 && strcmp(compat, "riscv"))
119 seq_printf(m, "uarch\t\t: %s\n", compat);
120 seq_puts(m, "\n");
121 of_node_put(node);
122
123 return 0;
124}
125
126const struct seq_operations cpuinfo_op = {
127 .start = c_start,
128 .next = c_next,
129 .stop = c_stop,
130 .show = c_show
131};
132
133#endif /* CONFIG_PROC_FS */