1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2013 Altera Corporation
4 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
5 *
6 * Based on cpuinfo.c from microblaze
7 */
8
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/delay.h>
12#include <linux/seq_file.h>
13#include <linux/string.h>
14#include <linux/of.h>
15#include <asm/cpuinfo.h>
16
17struct cpuinfo cpuinfo;
18
19#define err_cpu(x) \
20	pr_err("ERROR: Nios II " x " different for kernel and DTS\n")
21
22static inline u32 fcpu(struct device_node *cpu, const char *n)
23{
24	u32 val = 0;
25
26	of_property_read_u32(cpu, n, &val);
27
28	return val;
29}
30
31void __init setup_cpuinfo(void)
32{
33	struct device_node *cpu;
34	const char *str;
35	int len;
36
37	cpu = of_get_cpu_node(0, NULL);
38	if (!cpu)
39		panic("%s: No CPU found in devicetree!\n", __func__);
40
41	if (!of_property_read_bool(cpu, "altr,has-initda"))
42		panic("initda instruction is unimplemented. Please update your "
43			"hardware system to have more than 4-byte line data "
44			"cache\n");
45
46	cpuinfo.cpu_clock_freq = fcpu(cpu, "clock-frequency");
47
48	str = of_get_property(cpu, "altr,implementation", &len);
49	if (str)
50		strscpy(cpuinfo.cpu_impl, str, sizeof(cpuinfo.cpu_impl));
51	else
52		strcpy(cpuinfo.cpu_impl, "<unknown>");
53
54	cpuinfo.has_div = of_property_read_bool(cpu, "altr,has-div");
55	cpuinfo.has_mul = of_property_read_bool(cpu, "altr,has-mul");
56	cpuinfo.has_mulx = of_property_read_bool(cpu, "altr,has-mulx");
57	cpuinfo.has_bmx = of_property_read_bool(cpu, "altr,has-bmx");
58	cpuinfo.has_cdx = of_property_read_bool(cpu, "altr,has-cdx");
59	cpuinfo.mmu = of_property_read_bool(cpu, "altr,has-mmu");
60
61	if (IS_ENABLED(CONFIG_NIOS2_HW_DIV_SUPPORT) && !cpuinfo.has_div)
62		err_cpu("DIV");
63
64	if (IS_ENABLED(CONFIG_NIOS2_HW_MUL_SUPPORT) && !cpuinfo.has_mul)
65		err_cpu("MUL");
66
67	if (IS_ENABLED(CONFIG_NIOS2_HW_MULX_SUPPORT) && !cpuinfo.has_mulx)
68		err_cpu("MULX");
69
70	if (IS_ENABLED(CONFIG_NIOS2_BMX_SUPPORT) && !cpuinfo.has_bmx)
71		err_cpu("BMX");
72
73	if (IS_ENABLED(CONFIG_NIOS2_CDX_SUPPORT) && !cpuinfo.has_cdx)
74		err_cpu("CDX");
75
76	cpuinfo.tlb_num_ways = fcpu(cpu, "altr,tlb-num-ways");
77	if (!cpuinfo.tlb_num_ways)
78		panic("altr,tlb-num-ways can't be 0. Please check your hardware "
79			"system\n");
80	cpuinfo.icache_line_size = fcpu(cpu, "icache-line-size");
81	cpuinfo.icache_size = fcpu(cpu, "icache-size");
82	if (CONFIG_NIOS2_ICACHE_SIZE != cpuinfo.icache_size)
83		pr_warn("Warning: icache size configuration mismatch "
84		"(0x%x vs 0x%x) of CONFIG_NIOS2_ICACHE_SIZE vs "
85		"device tree icache-size\n",
86		CONFIG_NIOS2_ICACHE_SIZE, cpuinfo.icache_size);
87
88	cpuinfo.dcache_line_size = fcpu(cpu, "dcache-line-size");
89	if (CONFIG_NIOS2_DCACHE_LINE_SIZE != cpuinfo.dcache_line_size)
90		pr_warn("Warning: dcache line size configuration mismatch "
91		"(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_LINE_SIZE vs "
92		"device tree dcache-line-size\n",
93		CONFIG_NIOS2_DCACHE_LINE_SIZE, cpuinfo.dcache_line_size);
94	cpuinfo.dcache_size = fcpu(cpu, "dcache-size");
95	if (CONFIG_NIOS2_DCACHE_SIZE != cpuinfo.dcache_size)
96		pr_warn("Warning: dcache size configuration mismatch "
97			"(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_SIZE vs "
98			"device tree dcache-size\n",
99			CONFIG_NIOS2_DCACHE_SIZE, cpuinfo.dcache_size);
100
101	cpuinfo.tlb_pid_num_bits = fcpu(cpu, "altr,pid-num-bits");
102	cpuinfo.tlb_num_ways_log2 = ilog2(cpuinfo.tlb_num_ways);
103	cpuinfo.tlb_num_entries = fcpu(cpu, "altr,tlb-num-entries");
104	cpuinfo.tlb_num_lines = cpuinfo.tlb_num_entries / cpuinfo.tlb_num_ways;
105	cpuinfo.tlb_ptr_sz = fcpu(cpu, "altr,tlb-ptr-sz");
106
107	cpuinfo.reset_addr = fcpu(cpu, "altr,reset-addr");
108	cpuinfo.exception_addr = fcpu(cpu, "altr,exception-addr");
109	cpuinfo.fast_tlb_miss_exc_addr = fcpu(cpu, "altr,fast-tlb-miss-addr");
110
111	of_node_put(cpu);
112}
113
114#ifdef CONFIG_PROC_FS
115
116/*
117 * Get CPU information for use by the procfs.
118 */
119static int show_cpuinfo(struct seq_file *m, void *v)
120{
121	const u32 clockfreq = cpuinfo.cpu_clock_freq;
122
123	seq_printf(m,
124		   "CPU:\t\tNios II/%s\n"
125		   "REV:\t\t%i\n"
126		   "MMU:\t\t%s\n"
127		   "FPU:\t\tnone\n"
128		   "Clocking:\t%u.%02u MHz\n"
129		   "BogoMips:\t%lu.%02lu\n"
130		   "Calibration:\t%lu loops\n",
131		   cpuinfo.cpu_impl,
132		   CONFIG_NIOS2_ARCH_REVISION,
133		   cpuinfo.mmu ? "present" : "none",
134		   clockfreq / 1000000, (clockfreq / 100000) % 10,
135		   (loops_per_jiffy * HZ) / 500000,
136		   ((loops_per_jiffy * HZ) / 5000) % 100,
137		   (loops_per_jiffy * HZ));
138
139	seq_printf(m,
140		   "HW:\n"
141		   " MUL:\t\t%s\n"
142		   " MULX:\t\t%s\n"
143		   " DIV:\t\t%s\n"
144		   " BMX:\t\t%s\n"
145		   " CDX:\t\t%s\n",
146		   cpuinfo.has_mul ? "yes" : "no",
147		   cpuinfo.has_mulx ? "yes" : "no",
148		   cpuinfo.has_div ? "yes" : "no",
149		   cpuinfo.has_bmx ? "yes" : "no",
150		   cpuinfo.has_cdx ? "yes" : "no");
151
152	seq_printf(m,
153		   "Icache:\t\t%ukB, line length: %u\n",
154		   cpuinfo.icache_size >> 10,
155		   cpuinfo.icache_line_size);
156
157	seq_printf(m,
158		   "Dcache:\t\t%ukB, line length: %u\n",
159		   cpuinfo.dcache_size >> 10,
160		   cpuinfo.dcache_line_size);
161
162	seq_printf(m,
163		   "TLB:\t\t%u ways, %u entries, %u PID bits\n",
164		   cpuinfo.tlb_num_ways,
165		   cpuinfo.tlb_num_entries,
166		   cpuinfo.tlb_pid_num_bits);
167
168	return 0;
169}
170
171static void *cpuinfo_start(struct seq_file *m, loff_t *pos)
172{
173	unsigned long i = *pos;
174
175	return i < num_possible_cpus() ? (void *) (i + 1) : NULL;
176}
177
178static void *cpuinfo_next(struct seq_file *m, void *v, loff_t *pos)
179{
180	++*pos;
181	return cpuinfo_start(m, pos);
182}
183
184static void cpuinfo_stop(struct seq_file *m, void *v)
185{
186}
187
188const struct seq_operations cpuinfo_op = {
189	.start	= cpuinfo_start,
190	.next	= cpuinfo_next,
191	.stop	= cpuinfo_stop,
192	.show	= show_cpuinfo
193};
194
195#endif /* CONFIG_PROC_FS */
196