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