Quelle  cpuinfo.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2013 Altera Corporation
 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
 *
 * Based on cpuinfo.c from microblaze
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/of.h>
#include <asm/cpuinfo.h>

struct cpuinfo cpuinfo;

#define err_cpu(x) \
 pr_err("ERROR: Nios II " x " different for kernel and DTS\n")

static inline u32 fcpu(struct device_node *cpu, const char *n)
{
 u32 val = 0;

 of_property_read_u32(cpu, n, &val);

 return val;
}

void __init setup_cpuinfo(void)
{
 struct device_node *cpu;
 const char *str;
 int len;

 cpu = of_get_cpu_node(0, NULL);
 if (!cpu)
  panic("%s: No CPU found in devicetree!\n", __func__);

 if (!of_property_read_bool(cpu, "altr,has-initda"))
  panic("initda instruction is unimplemented. Please update your "
   "hardware system to have more than 4-byte line data "
   "cache\n");

 cpuinfo.cpu_clock_freq = fcpu(cpu, "clock-frequency");

 str = of_get_property(cpu, "altr,implementation", &len);
 strscpy(cpuinfo.cpu_impl, str ?: "");

 cpuinfo.has_div = of_property_read_bool(cpu, "altr,has-div");
 cpuinfo.has_mul = of_property_read_bool(cpu, "altr,has-mul");
 cpuinfo.has_mulx = of_property_read_bool(cpu, "altr,has-mulx");
 cpuinfo.has_bmx = of_property_read_bool(cpu, "altr,has-bmx");
 cpuinfo.has_cdx = of_property_read_bool(cpu, "altr,has-cdx");
 cpuinfo.mmu = of_property_read_bool(cpu, "altr,has-mmu");

 if (IS_ENABLED(CONFIG_NIOS2_HW_DIV_SUPPORT) && !cpuinfo.has_div)
  err_cpu("DIV");

 if (IS_ENABLED(CONFIG_NIOS2_HW_MUL_SUPPORT) && !cpuinfo.has_mul)
  err_cpu("MUL");

 if (IS_ENABLED(CONFIG_NIOS2_HW_MULX_SUPPORT) && !cpuinfo.has_mulx)
  err_cpu("MULX");

 if (IS_ENABLED(CONFIG_NIOS2_BMX_SUPPORT) && !cpuinfo.has_bmx)
  err_cpu("BMX");

 if (IS_ENABLED(CONFIG_NIOS2_CDX_SUPPORT) && !cpuinfo.has_cdx)
  err_cpu("CDX");

 cpuinfo.tlb_num_ways = fcpu(cpu, "altr,tlb-num-ways");
 if (!cpuinfo.tlb_num_ways)
  panic("altr,tlb-num-ways can't be 0. Please check your hardware "
   "system\n");
 cpuinfo.icache_line_size = fcpu(cpu, "icache-line-size");
 cpuinfo.icache_size = fcpu(cpu, "icache-size");
 if (CONFIG_NIOS2_ICACHE_SIZE != cpuinfo.icache_size)
  pr_warn("Warning: icache size configuration mismatch "
  "(0x%x vs 0x%x) of CONFIG_NIOS2_ICACHE_SIZE vs "
  "device tree icache-size\n",
  CONFIG_NIOS2_ICACHE_SIZE, cpuinfo.icache_size);

 cpuinfo.dcache_line_size = fcpu(cpu, "dcache-line-size");
 if (CONFIG_NIOS2_DCACHE_LINE_SIZE != cpuinfo.dcache_line_size)
  pr_warn("Warning: dcache line size configuration mismatch "
  "(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_LINE_SIZE vs "
  "device tree dcache-line-size\n",
  CONFIG_NIOS2_DCACHE_LINE_SIZE, cpuinfo.dcache_line_size);
 cpuinfo.dcache_size = fcpu(cpu, "dcache-size");
 if (CONFIG_NIOS2_DCACHE_SIZE != cpuinfo.dcache_size)
  pr_warn("Warning: dcache size configuration mismatch "
   "(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_SIZE vs "
   "device tree dcache-size\n",
   CONFIG_NIOS2_DCACHE_SIZE, cpuinfo.dcache_size);

 cpuinfo.tlb_pid_num_bits = fcpu(cpu, "altr,pid-num-bits");
 cpuinfo.tlb_num_ways_log2 = ilog2(cpuinfo.tlb_num_ways);
 cpuinfo.tlb_num_entries = fcpu(cpu, "altr,tlb-num-entries");
 cpuinfo.tlb_num_lines = cpuinfo.tlb_num_entries / cpuinfo.tlb_num_ways;
 cpuinfo.tlb_ptr_sz = fcpu(cpu, "altr,tlb-ptr-sz");

 cpuinfo.reset_addr = fcpu(cpu, "altr,reset-addr");
 cpuinfo.exception_addr = fcpu(cpu, "altr,exception-addr");
 cpuinfo.fast_tlb_miss_exc_addr = fcpu(cpu, "altr,fast-tlb-miss-addr");

 of_node_put(cpu);
}

#ifdef CONFIG_PROC_FS

/*
 * Get CPU information for use by the procfs.
 */
static int show_cpuinfo(struct seq_file *m, void *v)
{
 const u32 clockfreq = cpuinfo.cpu_clock_freq;

 seq_printf(m,
     "CPU:\t\tNios II/%s\n"
     "REV:\t\t%i\n"
     "MMU:\t\t%s\n"
     "FPU:\t\tnone\n"
     "Clocking:\t%u.%02u MHz\n"
     "BogoMips:\t%lu.%02lu\n"
     "Calibration:\t%lu loops\n",
     cpuinfo.cpu_impl,
     CONFIG_NIOS2_ARCH_REVISION,
     cpuinfo.mmu ? "present" : "none",
     clockfreq / 1000000, (clockfreq / 100000) % 10,
     (loops_per_jiffy * HZ) / 500000,
     ((loops_per_jiffy * HZ) / 5000) % 100,
     (loops_per_jiffy * HZ));

 seq_printf(m,
     "HW:\n"
     " MUL:\t\t%s\n"
     " MULX:\t\t%s\n"
     " DIV:\t\t%s\n"
     " BMX:\t\t%s\n"
     " CDX:\t\t%s\n",
     str_yes_no(cpuinfo.has_mul),
     str_yes_no(cpuinfo.has_mulx),
     str_yes_no(cpuinfo.has_div),
     str_yes_no(cpuinfo.has_bmx),
     str_yes_no(cpuinfo.has_cdx));

 seq_printf(m,
     "Icache:\t\t%ukB, line length: %u\n",
     cpuinfo.icache_size >> 10,
     cpuinfo.icache_line_size);

 seq_printf(m,
     "Dcache:\t\t%ukB, line length: %u\n",
     cpuinfo.dcache_size >> 10,
     cpuinfo.dcache_line_size);

 seq_printf(m,
     "TLB:\t\t%u ways, %u entries, %u PID bits\n",
     cpuinfo.tlb_num_ways,
     cpuinfo.tlb_num_entries,
     cpuinfo.tlb_pid_num_bits);

 return 0;
}

static void *cpuinfo_start(struct seq_file *m, loff_t *pos)
{
 unsigned long i = *pos;

 return i < num_possible_cpus() ? (void *) (i + 1) : NULL;
}

static void *cpuinfo_next(struct seq_file *m, void *v, loff_t *pos)
{
 ++*pos;
 return cpuinfo_start(m, pos);
}

static void cpuinfo_stop(struct seq_file *m, void *v)
{
}

const struct seq_operations cpuinfo_op = {
 .start = cpuinfo_start,
 .next = cpuinfo_next,
 .stop = cpuinfo_stop,
 .show = show_cpuinfo
};

#endif /* CONFIG_PROC_FS */