arch/mips/generic/init.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2016 Imagination Technologies
   4  * Author: Paul Burton <paul.burton@mips.com>
   5  */
   6
   7 #include <linux/clk.h>
   8 #include <linux/clocksource.h>
   9 #include <linux/init.h>
  10 #include <linux/irqchip.h>
  11 #include <linux/of_clk.h>
  12 #include <linux/of_fdt.h>
  13
  14 #include <asm/bootinfo.h>
  15 #include <asm/fw/fw.h>
  16 #include <asm/irq_cpu.h>
  17 #include <asm/machine.h>
  18 #include <asm/mips-cps.h>
  19 #include <asm/prom.h>
  20 #include <asm/smp-ops.h>
  21 #include <asm/time.h>
  22
  23 static __initconst const void *fdt;
  24 static __initconst const struct mips_machine *mach;
  25 static __initconst const void *mach_match_data;
  26
  27 void __init prom_init(void)
  28 {
  29         plat_get_fdt();
  30         BUG_ON(!fdt);
  31 }
  32
  33 void __init *plat_get_fdt(void)
  34 {
  35         const struct mips_machine *check_mach;
  36         const struct of_device_id *match;
  37
  38         if (fdt)
  39                 /* Already set up */
  40                 return (void *)fdt;
  41
  42         if (fw_passed_dtb && !fdt_check_header((void *)fw_passed_dtb)) {
  43                 /*
  44                  * We have been provided with the appropriate device tree for
  45                  * the board. Make use of it & search for any machine struct
  46                  * based upon the root compatible string.
  47                  */
  48                 fdt = (void *)fw_passed_dtb;
  49
  50                 for_each_mips_machine(check_mach) {
  51                         match = mips_machine_is_compatible(check_mach, fdt);
  52                         if (match) {
  53                                 mach = check_mach;
  54                                 mach_match_data = match->data;
  55                                 break;
  56                         }
  57                 }
  58         } else if (IS_ENABLED(CONFIG_LEGACY_BOARDS)) {
  59                 /*
  60                  * We weren't booted using the UHI boot protocol, but do
  61                  * support some number of boards with legacy boot protocols.
  62                  * Attempt to find the right one.
  63                  */
  64                 for_each_mips_machine(check_mach) {
  65                         if (!check_mach->detect)
  66                                 continue;
  67
  68                         if (!check_mach->detect())
  69                                 continue;
  70
  71                         mach = check_mach;
  72                 }
  73
  74                 /*
  75                  * If we don't recognise the machine then we can't continue, so
  76                  * die here.
  77                  */
  78                 BUG_ON(!mach);
  79
  80                 /* Retrieve the machine's FDT */
  81                 fdt = mach->fdt;
  82         }
  83         return (void *)fdt;
  84 }
  85
  86 #ifdef CONFIG_RELOCATABLE
  87
  88 void __init plat_fdt_relocated(void *new_location)
  89 {
  90         /*
  91          * reset fdt as the cached value would point to the location
  92          * before relocations happened and update the location argument
  93          * if it was passed using UHI
  94          */
  95         fdt = NULL;
  96
  97         if (fw_arg0 == -2)
  98                 fw_arg1 = (unsigned long)new_location;
  99 }
 100
 101 #endif /* CONFIG_RELOCATABLE */
 102
 103 void __init plat_mem_setup(void)
 104 {
 105         if (mach && mach->fixup_fdt)
 106                 fdt = mach->fixup_fdt(fdt, mach_match_data);
 107
 108         fw_init_cmdline();
 109         __dt_setup_arch((void *)fdt);
 110 }
 111
 112 void __init device_tree_init(void)
 113 {
 114         int err;
 115
 116         unflatten_and_copy_device_tree();
 117         mips_cpc_probe();
 118
 119         err = register_cps_smp_ops();
 120         if (err)
 121                 err = register_up_smp_ops();
 122 }
 123
 124 int __init apply_mips_fdt_fixups(void *fdt_out, size_t fdt_out_size,
 125                                  const void *fdt_in,
 126                                  const struct mips_fdt_fixup *fixups)
 127 {
 128         int err;
 129
 130         err = fdt_open_into(fdt_in, fdt_out, fdt_out_size);
 131         if (err) {
 132                 pr_err("Failed to open FDT\n");
 133                 return err;
 134         }
 135
 136         for (; fixups->apply; fixups++) {
 137                 err = fixups->apply(fdt_out);
 138                 if (err) {
 139                         pr_err("Failed to apply FDT fixup \"%s\"\n",
 140                                fixups->description);
 141                         return err;
 142                 }
 143         }
 144
 145         err = fdt_pack(fdt_out);
 146         if (err)
 147                 pr_err("Failed to pack FDT\n");
 148         return err;
 149 }
 150
 151 void __init plat_time_init(void)
 152 {
 153         struct device_node *np;
 154         struct clk *clk;
 155
 156         of_clk_init(NULL);
 157
 158         if (!cpu_has_counter) {
 159                 mips_hpt_frequency = 0;
 160         } else if (mach && mach->measure_hpt_freq) {
 161                 mips_hpt_frequency = mach->measure_hpt_freq();
 162         } else {
 163                 np = of_get_cpu_node(0, NULL);
 164                 if (!np) {
 165                         pr_err("Failed to get CPU node\n");
 166                         return;
 167                 }
 168
 169                 clk = of_clk_get(np, 0);
 170                 if (IS_ERR(clk)) {
 171                         pr_err("Failed to get CPU clock: %ld\n", PTR_ERR(clk));
 172                         return;
 173                 }
 174
 175                 mips_hpt_frequency = clk_get_rate(clk);
 176                 clk_put(clk);
 177
 178                 switch (boot_cpu_type()) {
 179                 case CPU_20KC:
 180                 case CPU_25KF:
 181                         /* The counter runs at the CPU clock rate */
 182                         break;
 183                 default:
 184                         /* The counter runs at half the CPU clock rate */
 185                         mips_hpt_frequency /= 2;
 186                         break;
 187                 }
 188         }
 189
 190         timer_probe();
 191 }
 192
 193 void __init arch_init_irq(void)
 194 {
 195         struct device_node *intc_node;
 196
 197         intc_node = of_find_compatible_node(NULL, NULL,
 198                                             "mti,cpu-interrupt-controller");
 199         if (!cpu_has_veic && !intc_node)
 200                 mips_cpu_irq_init();
 201         of_node_put(intc_node);
 202
 203         irqchip_init();
 204 }
 205
 206 void __init prom_free_prom_memory(void)
 207 {
 208 }