arch/nios2/kernel/cpuinfo.c

   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         int count = 0;
 130         const u32 clockfreq = cpuinfo.cpu_clock_freq;
 131
 132         count = seq_printf(m,
 133                         "CPU:\t\tNios II/%s\n"
 134                         "MMU:\t\t%s\n"
 135                         "FPU:\t\tnone\n"
 136                         "Clocking:\t%u.%02u MHz\n"
 137                         "BogoMips:\t%lu.%02lu\n"
 138                         "Calibration:\t%lu loops\n",
 139                         cpuinfo.cpu_impl,
 140                         cpuinfo.mmu ? "present" : "none",
 141                         clockfreq / 1000000, (clockfreq / 100000) % 10,
 142                         (loops_per_jiffy * HZ) / 500000,
 143                         ((loops_per_jiffy * HZ) / 5000) % 100,
 144                         (loops_per_jiffy * HZ));
 145
 146         count += seq_printf(m,
 147                         "HW:\n"
 148                         " MUL:\t\t%s\n"
 149                         " MULX:\t\t%s\n"
 150                         " DIV:\t\t%s\n",
 151                         cpuinfo.has_mul ? "yes" : "no",
 152                         cpuinfo.has_mulx ? "yes" : "no",
 153                         cpuinfo.has_div ? "yes" : "no");
 154
 155         count += seq_printf(m,
 156                         "Icache:\t\t%ukB, line length: %u\n",
 157                         cpuinfo.icache_size >> 10,
 158                         cpuinfo.icache_line_size);
 159
 160         count += seq_printf(m,
 161                         "Dcache:\t\t%ukB, line length: %u\n",
 162                         cpuinfo.dcache_size >> 10,
 163                         cpuinfo.dcache_line_size);
 164
 165         count += seq_printf(m,
 166                         "TLB:\t\t%u ways, %u entries, %u PID bits\n",
 167                         cpuinfo.tlb_num_ways,
 168                         cpuinfo.tlb_num_entries,
 169                         cpuinfo.tlb_pid_num_bits);
 170
 171         return 0;
 172 }
 173
 174 static void *cpuinfo_start(struct seq_file *m, loff_t *pos)
 175 {
 176         unsigned long i = *pos;
 177
 178         return i < num_possible_cpus() ? (void *) (i + 1) : NULL;
 179 }
 180
 181 static void *cpuinfo_next(struct seq_file *m, void *v, loff_t *pos)
 182 {
 183         ++*pos;
 184         return cpuinfo_start(m, pos);
 185 }
 186
 187 static void cpuinfo_stop(struct seq_file *m, void *v)
 188 {
 189 }
 190
 191 const struct seq_operations cpuinfo_op = {
 192         .start  = cpuinfo_start,
 193         .next   = cpuinfo_next,
 194         .stop   = cpuinfo_stop,
 195         .show   = show_cpuinfo
 196 };
 197
 198 #endif /* CONFIG_PROC_FS */