arch/mips/generic/init.c

   1 /*
   2  * Copyright (C) 2016 Imagination Technologies
   3  * Author: Paul Burton <paul.burton@imgtec.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation;  either version 2 of the  License, or (at your
   8  * option) any later version.
   9  */
  10
  11 #include <linux/clk.h>
  12 #include <linux/clk-provider.h>
  13 #include <linux/clocksource.h>
  14 #include <linux/init.h>
  15 #include <linux/irqchip.h>
  16 #include <linux/of_fdt.h>
  17 #include <linux/of_platform.h>
  18
  19 #include <asm/fw/fw.h>
  20 #include <asm/irq_cpu.h>
  21 #include <asm/machine.h>
  22 #include <asm/mips-cpc.h>
  23 #include <asm/prom.h>
  24 #include <asm/smp-ops.h>
  25 #include <asm/time.h>
  26
  27 static __initdata const void *fdt;
  28 static __initdata const struct mips_machine *mach;
  29 static __initdata const void *mach_match_data;
  30
  31 void __init prom_init(void)
  32 {
  33         const struct mips_machine *check_mach;
  34         const struct of_device_id *match;
  35
  36         if ((fw_arg0 == -2) && !fdt_check_header((void *)fw_arg1)) {
  37                 /*
  38                  * We booted using the UHI boot protocol, so we have been
  39                  * provided with the appropriate device tree for the board.
  40                  * Make use of it & search for any machine struct based upon
  41                  * the root compatible string.
  42                  */
  43                 fdt = (void *)fw_arg1;
  44
  45                 for_each_mips_machine(check_mach) {
  46                         match = mips_machine_is_compatible(check_mach, fdt);
  47                         if (match) {
  48                                 mach = check_mach;
  49                                 mach_match_data = match->data;
  50                                 break;
  51                         }
  52                 }
  53         } else if (IS_ENABLED(CONFIG_LEGACY_BOARDS)) {
  54                 /*
  55                  * We weren't booted using the UHI boot protocol, but do
  56                  * support some number of boards with legacy boot protocols.
  57                  * Attempt to find the right one.
  58                  */
  59                 for_each_mips_machine(check_mach) {
  60                         if (!check_mach->detect)
  61                                 continue;
  62
  63                         if (!check_mach->detect())
  64                                 continue;
  65
  66                         mach = check_mach;
  67                 }
  68
  69                 /*
  70                  * If we don't recognise the machine then we can't continue, so
  71                  * die here.
  72                  */
  73                 BUG_ON(!mach);
  74
  75                 /* Retrieve the machine's FDT */
  76                 fdt = mach->fdt;
  77         }
  78
  79         BUG_ON(!fdt);
  80 }
  81
  82 void __init *plat_get_fdt(void)
  83 {
  84         return (void *)fdt;
  85 }
  86
  87 void __init plat_mem_setup(void)
  88 {
  89         if (mach && mach->fixup_fdt)
  90                 fdt = mach->fixup_fdt(fdt, mach_match_data);
  91
  92         strlcpy(arcs_cmdline, boot_command_line, COMMAND_LINE_SIZE);
  93         __dt_setup_arch((void *)fdt);
  94 }
  95
  96 void __init device_tree_init(void)
  97 {
  98         int err;
  99
 100         unflatten_and_copy_device_tree();
 101         mips_cpc_probe();
 102
 103         err = register_cps_smp_ops();
 104         if (err)
 105                 err = register_up_smp_ops();
 106 }
 107
 108 void __init plat_time_init(void)
 109 {
 110         struct device_node *np;
 111         struct clk *clk;
 112
 113         of_clk_init(NULL);
 114
 115         if (!cpu_has_counter) {
 116                 mips_hpt_frequency = 0;
 117         } else if (mach && mach->measure_hpt_freq) {
 118                 mips_hpt_frequency = mach->measure_hpt_freq();
 119         } else {
 120                 np = of_get_cpu_node(0, NULL);
 121                 if (!np) {
 122                         pr_err("Failed to get CPU node\n");
 123                         return;
 124                 }
 125
 126                 clk = of_clk_get(np, 0);
 127                 if (IS_ERR(clk)) {
 128                         pr_err("Failed to get CPU clock: %ld\n", PTR_ERR(clk));
 129                         return;
 130                 }
 131
 132                 mips_hpt_frequency = clk_get_rate(clk);
 133                 clk_put(clk);
 134
 135                 switch (boot_cpu_type()) {
 136                 case CPU_20KC:
 137                 case CPU_25KF:
 138                         /* The counter runs at the CPU clock rate */
 139                         break;
 140                 default:
 141                         /* The counter runs at half the CPU clock rate */
 142                         mips_hpt_frequency /= 2;
 143                         break;
 144                 }
 145         }
 146
 147         clocksource_probe();
 148 }
 149
 150 void __init arch_init_irq(void)
 151 {
 152         struct device_node *intc_node;
 153
 154         intc_node = of_find_compatible_node(NULL, NULL,
 155                                             "mti,cpu-interrupt-controller");
 156         if (!cpu_has_veic && !intc_node)
 157                 mips_cpu_irq_init();
 158
 159         irqchip_init();
 160 }
 161
 162 static int __init publish_devices(void)
 163 {
 164         if (!of_have_populated_dt())
 165                 panic("Device-tree not present");
 166
 167         if (of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL))
 168                 panic("Failed to populate DT");
 169
 170         return 0;
 171 }
 172 arch_initcall(publish_devices);
 173
 174 void __init prom_free_prom_memory(void)
 175 {
 176 }