xref: /openbmc/linux/arch/nios2/kernel/cpuinfo.c (revision 976fa9a3)
1 /*
2  * Copyright (C) 2013 Altera Corporation
3  * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
4  *
5  * Based on cpuinfo.c from microblaze
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
19  *
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/delay.h>
25 #include <linux/seq_file.h>
26 #include <linux/string.h>
27 #include <linux/of.h>
28 #include <asm/cpuinfo.h>
29 
30 struct cpuinfo cpuinfo;
31 
32 #define err_cpu(x) \
33 	pr_err("ERROR: Nios II " x " different for kernel and DTS\n")
34 
35 static inline u32 fcpu(struct device_node *cpu, const char *n)
36 {
37 	u32 val = 0;
38 
39 	of_property_read_u32(cpu, n, &val);
40 
41 	return val;
42 }
43 
44 static inline u32 fcpu_has(struct device_node *cpu, const char *n)
45 {
46 	return of_get_property(cpu, n, NULL) ? 1 : 0;
47 }
48 
49 void __init setup_cpuinfo(void)
50 {
51 	struct device_node *cpu;
52 	const char *str;
53 	int len;
54 
55 	cpu = of_find_node_by_type(NULL, "cpu");
56 	if (!cpu)
57 		panic("%s: No CPU found in devicetree!\n", __func__);
58 
59 	if (!fcpu_has(cpu, "altr,has-initda"))
60 		panic("initda instruction is unimplemented. Please update your "
61 			"hardware system to have more than 4-byte line data "
62 			"cache\n");
63 
64 	cpuinfo.cpu_clock_freq = fcpu(cpu, "clock-frequency");
65 
66 	str = of_get_property(cpu, "altr,implementation", &len);
67 	if (str)
68 		strlcpy(cpuinfo.cpu_impl, str, sizeof(cpuinfo.cpu_impl));
69 	else
70 		strcpy(cpuinfo.cpu_impl, "<unknown>");
71 
72 	cpuinfo.has_div = fcpu_has(cpu, "altr,has-div");
73 	cpuinfo.has_mul = fcpu_has(cpu, "altr,has-mul");
74 	cpuinfo.has_mulx = fcpu_has(cpu, "altr,has-mulx");
75 	cpuinfo.mmu = fcpu_has(cpu, "altr,has-mmu");
76 
77 	if (IS_ENABLED(CONFIG_NIOS2_HW_DIV_SUPPORT) && !cpuinfo.has_div)
78 		err_cpu("DIV");
79 
80 	if (IS_ENABLED(CONFIG_NIOS2_HW_MUL_SUPPORT) && !cpuinfo.has_mul)
81 		err_cpu("MUL");
82 
83 	if (IS_ENABLED(CONFIG_NIOS2_HW_MULX_SUPPORT) && !cpuinfo.has_mulx)
84 		err_cpu("MULX");
85 
86 	cpuinfo.tlb_num_ways = fcpu(cpu, "altr,tlb-num-ways");
87 	if (!cpuinfo.tlb_num_ways)
88 		panic("altr,tlb-num-ways can't be 0. Please check your hardware "
89 			"system\n");
90 	cpuinfo.icache_line_size = fcpu(cpu, "icache-line-size");
91 	cpuinfo.icache_size = fcpu(cpu, "icache-size");
92 	if (CONFIG_NIOS2_ICACHE_SIZE != cpuinfo.icache_size)
93 		pr_warn("Warning: icache size configuration mismatch "
94 		"(0x%x vs 0x%x) of CONFIG_NIOS2_ICACHE_SIZE vs "
95 		"device tree icache-size\n",
96 		CONFIG_NIOS2_ICACHE_SIZE, cpuinfo.icache_size);
97 
98 	cpuinfo.dcache_line_size = fcpu(cpu, "dcache-line-size");
99 	if (CONFIG_NIOS2_DCACHE_LINE_SIZE != cpuinfo.dcache_line_size)
100 		pr_warn("Warning: dcache line size configuration mismatch "
101 		"(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_LINE_SIZE vs "
102 		"device tree dcache-line-size\n",
103 		CONFIG_NIOS2_DCACHE_LINE_SIZE, cpuinfo.dcache_line_size);
104 	cpuinfo.dcache_size = fcpu(cpu, "dcache-size");
105 	if (CONFIG_NIOS2_DCACHE_SIZE != cpuinfo.dcache_size)
106 		pr_warn("Warning: dcache size configuration mismatch "
107 			"(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_SIZE vs "
108 			"device tree dcache-size\n",
109 			CONFIG_NIOS2_DCACHE_SIZE, cpuinfo.dcache_size);
110 
111 	cpuinfo.tlb_pid_num_bits = fcpu(cpu, "altr,pid-num-bits");
112 	cpuinfo.tlb_num_ways_log2 = ilog2(cpuinfo.tlb_num_ways);
113 	cpuinfo.tlb_num_entries = fcpu(cpu, "altr,tlb-num-entries");
114 	cpuinfo.tlb_num_lines = cpuinfo.tlb_num_entries / cpuinfo.tlb_num_ways;
115 	cpuinfo.tlb_ptr_sz = fcpu(cpu, "altr,tlb-ptr-sz");
116 
117 	cpuinfo.reset_addr = fcpu(cpu, "altr,reset-addr");
118 	cpuinfo.exception_addr = fcpu(cpu, "altr,exception-addr");
119 	cpuinfo.fast_tlb_miss_exc_addr = fcpu(cpu, "altr,fast-tlb-miss-addr");
120 }
121 
122 #ifdef CONFIG_PROC_FS
123 
124 /*
125  * Get CPU information for use by the procfs.
126  */
127 static int show_cpuinfo(struct seq_file *m, void *v)
128 {
129 	const u32 clockfreq = cpuinfo.cpu_clock_freq;
130 
131 	seq_printf(m,
132 		   "CPU:\t\tNios II/%s\n"
133 		   "MMU:\t\t%s\n"
134 		   "FPU:\t\tnone\n"
135 		   "Clocking:\t%u.%02u MHz\n"
136 		   "BogoMips:\t%lu.%02lu\n"
137 		   "Calibration:\t%lu loops\n",
138 		   cpuinfo.cpu_impl,
139 		   cpuinfo.mmu ? "present" : "none",
140 		   clockfreq / 1000000, (clockfreq / 100000) % 10,
141 		   (loops_per_jiffy * HZ) / 500000,
142 		   ((loops_per_jiffy * HZ) / 5000) % 100,
143 		   (loops_per_jiffy * HZ));
144 
145 	seq_printf(m,
146 		   "HW:\n"
147 		   " MUL:\t\t%s\n"
148 		   " MULX:\t\t%s\n"
149 		   " DIV:\t\t%s\n",
150 		   cpuinfo.has_mul ? "yes" : "no",
151 		   cpuinfo.has_mulx ? "yes" : "no",
152 		   cpuinfo.has_div ? "yes" : "no");
153 
154 	seq_printf(m,
155 		   "Icache:\t\t%ukB, line length: %u\n",
156 		   cpuinfo.icache_size >> 10,
157 		   cpuinfo.icache_line_size);
158 
159 	seq_printf(m,
160 		   "Dcache:\t\t%ukB, line length: %u\n",
161 		   cpuinfo.dcache_size >> 10,
162 		   cpuinfo.dcache_line_size);
163 
164 	seq_printf(m,
165 		   "TLB:\t\t%u ways, %u entries, %u PID bits\n",
166 		   cpuinfo.tlb_num_ways,
167 		   cpuinfo.tlb_num_entries,
168 		   cpuinfo.tlb_pid_num_bits);
169 
170 	return 0;
171 }
172 
173 static void *cpuinfo_start(struct seq_file *m, loff_t *pos)
174 {
175 	unsigned long i = *pos;
176 
177 	return i < num_possible_cpus() ? (void *) (i + 1) : NULL;
178 }
179 
180 static void *cpuinfo_next(struct seq_file *m, void *v, loff_t *pos)
181 {
182 	++*pos;
183 	return cpuinfo_start(m, pos);
184 }
185 
186 static void cpuinfo_stop(struct seq_file *m, void *v)
187 {
188 }
189 
190 const struct seq_operations cpuinfo_op = {
191 	.start	= cpuinfo_start,
192 	.next	= cpuinfo_next,
193 	.stop	= cpuinfo_stop,
194 	.show	= show_cpuinfo
195 };
196 
197 #endif /* CONFIG_PROC_FS */
198