arch/mips/generic/init.c

   1 /*
   2  * Copyright (C) 2016 Imagination Technologies
   3  * Author: Paul Burton <paul.burton@mips.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
  18 #include <asm/bootinfo.h>
  19 #include <asm/fw/fw.h>
  20 #include <asm/irq_cpu.h>
  21 #include <asm/machine.h>
  22 #include <asm/mips-cps.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         plat_get_fdt();
  34         BUG_ON(!fdt);
  35 }
  36
  37 void __init *plat_get_fdt(void)
  38 {
  39         const struct mips_machine *check_mach;
  40         const struct of_device_id *match;
  41
  42         if (fdt)
  43                 /* Already set up */
  44                 return (void *)fdt;
  45
  46         if ((fw_arg0 == -2) && !fdt_check_header((void *)fw_arg1)) {
  47                 /*
  48                  * We booted using the UHI boot protocol, so we have been
  49                  * provided with the appropriate device tree for the board.
  50                  * Make use of it & search for any machine struct based upon
  51                  * the root compatible string.
  52                  */
  53                 fdt = (void *)fw_arg1;
  54
  55                 for_each_mips_machine(check_mach) {
  56                         match = mips_machine_is_compatible(check_mach, fdt);
  57                         if (match) {
  58                                 mach = check_mach;
  59                                 mach_match_data = match->data;
  60                                 break;
  61                         }
  62                 }
  63         } else if (IS_ENABLED(CONFIG_LEGACY_BOARDS)) {
  64                 /*
  65                  * We weren't booted using the UHI boot protocol, but do
  66                  * support some number of boards with legacy boot protocols.
  67                  * Attempt to find the right one.
  68                  */
  69                 for_each_mips_machine(check_mach) {
  70                         if (!check_mach->detect)
  71                                 continue;
  72
  73                         if (!check_mach->detect())
  74                                 continue;
  75
  76                         mach = check_mach;
  77                 }
  78
  79                 /*
  80                  * If we don't recognise the machine then we can't continue, so
  81                  * die here.
  82                  */
  83                 BUG_ON(!mach);
  84
  85                 /* Retrieve the machine's FDT */
  86                 fdt = mach->fdt;
  87         }
  88         return (void *)fdt;
  89 }
  90
  91 #ifdef CONFIG_RELOCATABLE
  92
  93 void __init plat_fdt_relocated(void *new_location)
  94 {
  95         /*
  96          * reset fdt as the cached value would point to the location
  97          * before relocations happened and update the location argument
  98          * if it was passed using UHI
  99          */
 100         fdt = NULL;
 101
 102         if (fw_arg0 == -2)
 103                 fw_arg1 = (unsigned long)new_location;
 104 }
 105
 106 #endif /* CONFIG_RELOCATABLE */
 107
 108 void __init plat_mem_setup(void)
 109 {
 110         if (mach && mach->fixup_fdt)
 111                 fdt = mach->fixup_fdt(fdt, mach_match_data);
 112
 113         strlcpy(arcs_cmdline, boot_command_line, COMMAND_LINE_SIZE);
 114         __dt_setup_arch((void *)fdt);
 115 }
 116
 117 void __init device_tree_init(void)
 118 {
 119         int err;
 120
 121         unflatten_and_copy_device_tree();
 122         mips_cpc_probe();
 123
 124         err = register_cps_smp_ops();
 125         if (err)
 126                 err = register_up_smp_ops();
 127 }
 128
 129 int __init apply_mips_fdt_fixups(void *fdt_out, size_t fdt_out_size,
 130                                  const void *fdt_in,
 131                                  const struct mips_fdt_fixup *fixups)
 132 {
 133         int err;
 134
 135         err = fdt_open_into(fdt_in, fdt_out, fdt_out_size);
 136         if (err) {
 137                 pr_err("Failed to open FDT\n");
 138                 return err;
 139         }
 140
 141         for (; fixups->apply; fixups++) {
 142                 err = fixups->apply(fdt_out);
 143                 if (err) {
 144                         pr_err("Failed to apply FDT fixup \"%s\"\n",
 145                                fixups->description);
 146                         return err;
 147                 }
 148         }
 149
 150         err = fdt_pack(fdt_out);
 151         if (err)
 152                 pr_err("Failed to pack FDT\n");
 153         return err;
 154 }
 155
 156 void __init plat_time_init(void)
 157 {
 158         struct device_node *np;
 159         struct clk *clk;
 160
 161         of_clk_init(NULL);
 162
 163         if (!cpu_has_counter) {
 164                 mips_hpt_frequency = 0;
 165         } else if (mach && mach->measure_hpt_freq) {
 166                 mips_hpt_frequency = mach->measure_hpt_freq();
 167         } else {
 168                 np = of_get_cpu_node(0, NULL);
 169                 if (!np) {
 170                         pr_err("Failed to get CPU node\n");
 171                         return;
 172                 }
 173
 174                 clk = of_clk_get(np, 0);
 175                 if (IS_ERR(clk)) {
 176                         pr_err("Failed to get CPU clock: %ld\n", PTR_ERR(clk));
 177                         return;
 178                 }
 179
 180                 mips_hpt_frequency = clk_get_rate(clk);
 181                 clk_put(clk);
 182
 183                 switch (boot_cpu_type()) {
 184                 case CPU_20KC:
 185                 case CPU_25KF:
 186                         /* The counter runs at the CPU clock rate */
 187                         break;
 188                 default:
 189                         /* The counter runs at half the CPU clock rate */
 190                         mips_hpt_frequency /= 2;
 191                         break;
 192                 }
 193         }
 194
 195         timer_probe();
 196 }
 197
 198 void __init arch_init_irq(void)
 199 {
 200         struct device_node *intc_node;
 201
 202         intc_node = of_find_compatible_node(NULL, NULL,
 203                                             "mti,cpu-interrupt-controller");
 204         if (!cpu_has_veic && !intc_node)
 205                 mips_cpu_irq_init();
 206
 207         irqchip_init();
 208 }
 209
 210 void __init prom_free_prom_memory(void)
 211 {
 212 }