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