mips/generic/init.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * Copyright (C) 2016 Imagination Technologies
0004  * Author: Paul Burton <paul.burton@mips.com>
0005  */
0006
0007 #include <linux/clk.h>
0008 #include <linux/clocksource.h>
0009 #include <linux/init.h>
0010 #include <linux/irqchip.h>
0011 #include <linux/of_clk.h>
0012 #include <linux/of_fdt.h>
0013
0014 #include <asm/bootinfo.h>
0015 #include <asm/fw/fw.h>
0016 #include <asm/irq_cpu.h>
0017 #include <asm/machine.h>
0018 #include <asm/mips-cps.h>
0019 #include <asm/prom.h>
0020 #include <asm/smp-ops.h>
0021 #include <asm/time.h>
0022
0023 static __initconst const void *fdt;
0024 static __initconst const struct mips_machine *mach;
0025 static __initconst const void *mach_match_data;
0026
0027 void __init prom_init(void)
0028 {
0029     plat_get_fdt();
0030     BUG_ON(!fdt);
0031 }
0032
0033 void __init *plat_get_fdt(void)
0034 {
0035     const struct mips_machine *check_mach;
0036     const struct of_device_id *match;
0037
0038     if (fdt)
0039         /* Already set up */
0040         return (void *)fdt;
0041
0042     fdt = (void *)get_fdt();
0043     if (fdt && !fdt_check_header(fdt)) {
0044         /*
0045          * We have been provided with the appropriate device tree for
0046          * the board. Make use of it & search for any machine struct
0047          * based upon the root compatible string.
0048          */
0049         for_each_mips_machine(check_mach) {
0050             match = mips_machine_is_compatible(check_mach, fdt);
0051             if (match) {
0052                 mach = check_mach;
0053                 mach_match_data = match->data;
0054                 break;
0055             }
0056         }
0057     } else if (IS_ENABLED(CONFIG_LEGACY_BOARDS)) {
0058         /*
0059          * We weren't booted using the UHI boot protocol, but do
0060          * support some number of boards with legacy boot protocols.
0061          * Attempt to find the right one.
0062          */
0063         for_each_mips_machine(check_mach) {
0064             if (!check_mach->detect)
0065                 continue;
0066
0067             if (!check_mach->detect())
0068                 continue;
0069
0070             mach = check_mach;
0071         }
0072
0073         /*
0074          * If we don't recognise the machine then we can't continue, so
0075          * die here.
0076          */
0077         BUG_ON(!mach);
0078
0079         /* Retrieve the machine's FDT */
0080         fdt = mach->fdt;
0081     }
0082     return (void *)fdt;
0083 }
0084
0085 #ifdef CONFIG_RELOCATABLE
0086
0087 void __init plat_fdt_relocated(void *new_location)
0088 {
0089     /*
0090      * reset fdt as the cached value would point to the location
0091      * before relocations happened and update the location argument
0092      * if it was passed using UHI
0093      */
0094     fdt = NULL;
0095
0096     if (fw_arg0 == -2)
0097         fw_arg1 = (unsigned long)new_location;
0098 }
0099
0100 #endif /* CONFIG_RELOCATABLE */
0101
0102 void __init plat_mem_setup(void)
0103 {
0104     if (mach && mach->fixup_fdt)
0105         fdt = mach->fixup_fdt(fdt, mach_match_data);
0106
0107     fw_init_cmdline();
0108     __dt_setup_arch((void *)fdt);
0109 }
0110
0111 void __init device_tree_init(void)
0112 {
0113     unflatten_and_copy_device_tree();
0114     mips_cpc_probe();
0115
0116     if (!register_cps_smp_ops())
0117         return;
0118     if (!register_vsmp_smp_ops())
0119         return;
0120
0121     register_up_smp_ops();
0122 }
0123
0124 int __init apply_mips_fdt_fixups(void *fdt_out, size_t fdt_out_size,
0125                  const void *fdt_in,
0126                  const struct mips_fdt_fixup *fixups)
0127 {
0128     int err;
0129
0130     err = fdt_open_into(fdt_in, fdt_out, fdt_out_size);
0131     if (err) {
0132         pr_err("Failed to open FDT\n");
0133         return err;
0134     }
0135
0136     for (; fixups->apply; fixups++) {
0137         err = fixups->apply(fdt_out);
0138         if (err) {
0139             pr_err("Failed to apply FDT fixup \"%s\"\n",
0140                    fixups->description);
0141             return err;
0142         }
0143     }
0144
0145     err = fdt_pack(fdt_out);
0146     if (err)
0147         pr_err("Failed to pack FDT\n");
0148     return err;
0149 }
0150
0151 void __init plat_time_init(void)
0152 {
0153     struct device_node *np;
0154     struct clk *clk;
0155
0156     of_clk_init(NULL);
0157
0158     if (!cpu_has_counter) {
0159         mips_hpt_frequency = 0;
0160     } else if (mach && mach->measure_hpt_freq) {
0161         mips_hpt_frequency = mach->measure_hpt_freq();
0162     } else {
0163         np = of_get_cpu_node(0, NULL);
0164         if (!np) {
0165             pr_err("Failed to get CPU node\n");
0166             return;
0167         }
0168
0169         clk = of_clk_get(np, 0);
0170         if (IS_ERR(clk)) {
0171             pr_err("Failed to get CPU clock: %ld\n", PTR_ERR(clk));
0172             return;
0173         }
0174
0175         mips_hpt_frequency = clk_get_rate(clk);
0176         clk_put(clk);
0177
0178         switch (boot_cpu_type()) {
0179         case CPU_20KC:
0180         case CPU_25KF:
0181             /* The counter runs at the CPU clock rate */
0182             break;
0183         default:
0184             /* The counter runs at half the CPU clock rate */
0185             mips_hpt_frequency /= 2;
0186             break;
0187         }
0188     }
0189
0190     timer_probe();
0191 }
0192
0193 void __init arch_init_irq(void)
0194 {
0195     struct device_node *intc_node;
0196
0197     intc_node = of_find_compatible_node(NULL, NULL,
0198                         "mti,cpu-interrupt-controller");
0199     if (!cpu_has_veic && !intc_node)
0200         mips_cpu_irq_init();
0201     of_node_put(intc_node);
0202
0203     irqchip_init();
0204 }