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 #include <linux/of_platform.h>
  18
  19 #include <asm/bootinfo.h>
  20 #include <asm/fw/fw.h>
  21 #include <asm/irq_cpu.h>
  22 #include <asm/machine.h>
  23 #include <asm/mips-cps.h>
  24 #include <asm/prom.h>
  25 #include <asm/smp-ops.h>
  26 #include <asm/time.h>
  27
  28 static __initdata const void *fdt;
  29 static __initdata const struct mips_machine *mach;
  30 static __initdata const void *mach_match_data;
  31
  32 void __init prom_init(void)
  33 {
  34         plat_get_fdt();
  35         BUG_ON(!fdt);
  36 }
  37
  38 void __init *plat_get_fdt(void)
  39 {
  40         const struct mips_machine *check_mach;
  41         const struct of_device_id *match;
  42
  43         if (fdt)
  44                 /* Already set up */
  45                 return (void *)fdt;
  46
  47         if ((fw_arg0 == -2) && !fdt_check_header((void *)fw_arg1)) {
  48                 /*
  49                  * We booted using the UHI boot protocol, so we have been
  50                  * provided with the appropriate device tree for the board.
  51                  * Make use of it & search for any machine struct based upon
  52                  * the root compatible string.
  53                  */
  54                 fdt = (void *)fw_arg1;
  55
  56                 for_each_mips_machine(check_mach) {
  57                         match = mips_machine_is_compatible(check_mach, fdt);
  58                         if (match) {
  59                                 mach = check_mach;
  60                                 mach_match_data = match->data;
  61                                 break;
  62                         }
  63                 }
  64         } else if (IS_ENABLED(CONFIG_LEGACY_BOARDS)) {
  65                 /*
  66                  * We weren't booted using the UHI boot protocol, but do
  67                  * support some number of boards with legacy boot protocols.
  68                  * Attempt to find the right one.
  69                  */
  70                 for_each_mips_machine(check_mach) {
  71                         if (!check_mach->detect)
  72                                 continue;
  73
  74                         if (!check_mach->detect())
  75                                 continue;
  76
  77                         mach = check_mach;
  78                 }
  79
  80                 /*
  81                  * If we don't recognise the machine then we can't continue, so
  82                  * die here.
  83                  */
  84                 BUG_ON(!mach);
  85
  86                 /* Retrieve the machine's FDT */
  87                 fdt = mach->fdt;
  88         }
  89         return (void *)fdt;
  90 }
  91
  92 #ifdef CONFIG_RELOCATABLE
  93
  94 void __init plat_fdt_relocated(void *new_location)
  95 {
  96         /*
  97          * reset fdt as the cached value would point to the location
  98          * before relocations happened and update the location argument
  99          * if it was passed using UHI
 100          */
 101         fdt = NULL;
 102
 103         if (fw_arg0 == -2)
 104                 fw_arg1 = (unsigned long)new_location;
 105 }
 106
 107 #endif /* CONFIG_RELOCATABLE */
 108
 109 void __init plat_mem_setup(void)
 110 {
 111         if (mach && mach->fixup_fdt)
 112                 fdt = mach->fixup_fdt(fdt, mach_match_data);
 113
 114         strlcpy(arcs_cmdline, boot_command_line, COMMAND_LINE_SIZE);
 115         __dt_setup_arch((void *)fdt);
 116 }
 117
 118 void __init device_tree_init(void)
 119 {
 120         int err;
 121
 122         unflatten_and_copy_device_tree();
 123         mips_cpc_probe();
 124
 125         err = register_cps_smp_ops();
 126         if (err)
 127                 err = register_up_smp_ops();
 128 }
 129
 130 int __init apply_mips_fdt_fixups(void *fdt_out, size_t fdt_out_size,
 131                                  const void *fdt_in,
 132                                  const struct mips_fdt_fixup *fixups)
 133 {
 134         int err;
 135
 136         err = fdt_open_into(fdt_in, fdt_out, fdt_out_size);
 137         if (err) {
 138                 pr_err("Failed to open FDT\n");
 139                 return err;
 140         }
 141
 142         for (; fixups->apply; fixups++) {
 143                 err = fixups->apply(fdt_out);
 144                 if (err) {
 145                         pr_err("Failed to apply FDT fixup \"%s\"\n",
 146                                fixups->description);
 147                         return err;
 148                 }
 149         }
 150
 151         err = fdt_pack(fdt_out);
 152         if (err)
 153                 pr_err("Failed to pack FDT\n");
 154         return err;
 155 }
 156
 157 void __init plat_time_init(void)
 158 {
 159         struct device_node *np;
 160         struct clk *clk;
 161
 162         of_clk_init(NULL);
 163
 164         if (!cpu_has_counter) {
 165                 mips_hpt_frequency = 0;
 166         } else if (mach && mach->measure_hpt_freq) {
 167                 mips_hpt_frequency = mach->measure_hpt_freq();
 168         } else {
 169                 np = of_get_cpu_node(0, NULL);
 170                 if (!np) {
 171                         pr_err("Failed to get CPU node\n");
 172                         return;
 173                 }
 174
 175                 clk = of_clk_get(np, 0);
 176                 if (IS_ERR(clk)) {
 177                         pr_err("Failed to get CPU clock: %ld\n", PTR_ERR(clk));
 178                         return;
 179                 }
 180
 181                 mips_hpt_frequency = clk_get_rate(clk);
 182                 clk_put(clk);
 183
 184                 switch (boot_cpu_type()) {
 185                 case CPU_20KC:
 186                 case CPU_25KF:
 187                         /* The counter runs at the CPU clock rate */
 188                         break;
 189                 default:
 190                         /* The counter runs at half the CPU clock rate */
 191                         mips_hpt_frequency /= 2;
 192                         break;
 193                 }
 194         }
 195
 196         timer_probe();
 197 }
 198
 199 void __init arch_init_irq(void)
 200 {
 201         struct device_node *intc_node;
 202
 203         intc_node = of_find_compatible_node(NULL, NULL,
 204                                             "mti,cpu-interrupt-controller");
 205         if (!cpu_has_veic && !intc_node)
 206                 mips_cpu_irq_init();
 207
 208         irqchip_init();
 209 }
 210
 211 static int __init publish_devices(void)
 212 {
 213         if (!of_have_populated_dt())
 214                 panic("Device-tree not present");
 215
 216         if (of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL))
 217                 panic("Failed to populate DT");
 218
 219         return 0;
 220 }
 221 arch_initcall(publish_devices);
 222
 223 void __init prom_free_prom_memory(void)
 224 {
 225 }