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 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 void __init plat_fdt_relocated(void *new_location) 92 { 93 /* 94 * reset fdt as the cached value would point to the location 95 * before relocations happened and update the location argument 96 * if it was passed using UHI 97 */ 98 fdt = NULL; 99 100 if (fw_arg0 == -2) 101 fw_arg1 = (unsigned long)new_location; 102 } 103 104 void __init plat_mem_setup(void) 105 { 106 if (mach && mach->fixup_fdt) 107 fdt = mach->fixup_fdt(fdt, mach_match_data); 108 109 strlcpy(arcs_cmdline, boot_command_line, COMMAND_LINE_SIZE); 110 __dt_setup_arch((void *)fdt); 111 } 112 113 void __init device_tree_init(void) 114 { 115 int err; 116 117 unflatten_and_copy_device_tree(); 118 mips_cpc_probe(); 119 120 err = register_cps_smp_ops(); 121 if (err) 122 err = register_up_smp_ops(); 123 } 124 125 void __init plat_time_init(void) 126 { 127 struct device_node *np; 128 struct clk *clk; 129 130 of_clk_init(NULL); 131 132 if (!cpu_has_counter) { 133 mips_hpt_frequency = 0; 134 } else if (mach && mach->measure_hpt_freq) { 135 mips_hpt_frequency = mach->measure_hpt_freq(); 136 } else { 137 np = of_get_cpu_node(0, NULL); 138 if (!np) { 139 pr_err("Failed to get CPU node\n"); 140 return; 141 } 142 143 clk = of_clk_get(np, 0); 144 if (IS_ERR(clk)) { 145 pr_err("Failed to get CPU clock: %ld\n", PTR_ERR(clk)); 146 return; 147 } 148 149 mips_hpt_frequency = clk_get_rate(clk); 150 clk_put(clk); 151 152 switch (boot_cpu_type()) { 153 case CPU_20KC: 154 case CPU_25KF: 155 /* The counter runs at the CPU clock rate */ 156 break; 157 default: 158 /* The counter runs at half the CPU clock rate */ 159 mips_hpt_frequency /= 2; 160 break; 161 } 162 } 163 164 clocksource_probe(); 165 } 166 167 void __init arch_init_irq(void) 168 { 169 struct device_node *intc_node; 170 171 intc_node = of_find_compatible_node(NULL, NULL, 172 "mti,cpu-interrupt-controller"); 173 if (!cpu_has_veic && !intc_node) 174 mips_cpu_irq_init(); 175 176 irqchip_init(); 177 } 178 179 static int __init publish_devices(void) 180 { 181 if (!of_have_populated_dt()) 182 panic("Device-tree not present"); 183 184 if (of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL)) 185 panic("Failed to populate DT"); 186 187 return 0; 188 } 189 arch_initcall(publish_devices); 190 191 void __init prom_free_prom_memory(void) 192 { 193 } 194