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
 30struct cpuinfo cpuinfo;
 31
 32#define err_cpu(x) \
 33	pr_err("ERROR: Nios II " x " different for kernel and DTS\n")
 34
 35static 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
 44static inline u32 fcpu_has(struct device_node *cpu, const char *n)
 45{
 46	return of_get_property(cpu, n, NULL) ? 1 : 0;
 47}
 48
 49void __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 */
127static 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
173static 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
180static void *cpuinfo_next(struct seq_file *m, void *v, loff_t *pos)
181{
182	++*pos;
183	return cpuinfo_start(m, pos);
184}
185
186static void cpuinfo_stop(struct seq_file *m, void *v)
187{
188}
189
190const 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 */