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 
17 struct cpuinfo cpuinfo;
18 
19 #define err_cpu(x) \
20 	pr_err("ERROR: Nios II " x " different for kernel and DTS\n")
21 
fcpu(struct device_node * cpu,const char * n)22 static 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 
setup_cpuinfo(void)31 void __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 		strlcpy(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  */
show_cpuinfo(struct seq_file * m,void * v)119 static 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 
cpuinfo_start(struct seq_file * m,loff_t * pos)171 static 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 
cpuinfo_next(struct seq_file * m,void * v,loff_t * pos)178 static void *cpuinfo_next(struct seq_file *m, void *v, loff_t *pos)
179 {
180 	++*pos;
181 	return cpuinfo_start(m, pos);
182 }
183 
cpuinfo_stop(struct seq_file * m,void * v)184 static void cpuinfo_stop(struct seq_file *m, void *v)
185 {
186 }
187 
188 const 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