xref: /openbmc/linux/arch/riscv/kernel/setup.c (revision b8265621)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
4  *  Chen Liqin <liqin.chen@sunplusct.com>
5  *  Lennox Wu <lennox.wu@sunplusct.com>
6  * Copyright (C) 2012 Regents of the University of California
7  */
8 
9 #include <linux/init.h>
10 #include <linux/mm.h>
11 #include <linux/memblock.h>
12 #include <linux/sched.h>
13 #include <linux/console.h>
14 #include <linux/screen_info.h>
15 #include <linux/of_fdt.h>
16 #include <linux/of_platform.h>
17 #include <linux/sched/task.h>
18 #include <linux/swiotlb.h>
19 #include <linux/smp.h>
20 
21 #include <asm/clint.h>
22 #include <asm/cpu_ops.h>
23 #include <asm/setup.h>
24 #include <asm/sections.h>
25 #include <asm/sbi.h>
26 #include <asm/tlbflush.h>
27 #include <asm/thread_info.h>
28 #include <asm/kasan.h>
29 
30 #include "head.h"
31 
32 #ifdef CONFIG_DUMMY_CONSOLE
33 struct screen_info screen_info = {
34 	.orig_video_lines	= 30,
35 	.orig_video_cols	= 80,
36 	.orig_video_mode	= 0,
37 	.orig_video_ega_bx	= 0,
38 	.orig_video_isVGA	= 1,
39 	.orig_video_points	= 8
40 };
41 #endif
42 
43 /*
44  * The lucky hart to first increment this variable will boot the other cores.
45  * This is used before the kernel initializes the BSS so it can't be in the
46  * BSS.
47  */
48 atomic_t hart_lottery __section(.sdata);
49 unsigned long boot_cpu_hartid;
50 static DEFINE_PER_CPU(struct cpu, cpu_devices);
51 
52 void __init parse_dtb(void)
53 {
54 	if (early_init_dt_scan(dtb_early_va))
55 		return;
56 
57 	pr_err("No DTB passed to the kernel\n");
58 #ifdef CONFIG_CMDLINE_FORCE
59 	strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
60 	pr_info("Forcing kernel command line to: %s\n", boot_command_line);
61 #endif
62 }
63 
64 void __init setup_arch(char **cmdline_p)
65 {
66 	init_mm.start_code = (unsigned long) _stext;
67 	init_mm.end_code   = (unsigned long) _etext;
68 	init_mm.end_data   = (unsigned long) _edata;
69 	init_mm.brk        = (unsigned long) _end;
70 
71 	*cmdline_p = boot_command_line;
72 
73 	parse_early_param();
74 
75 	setup_bootmem();
76 	paging_init();
77 #if IS_ENABLED(CONFIG_BUILTIN_DTB)
78 	unflatten_and_copy_device_tree();
79 #else
80 	unflatten_device_tree();
81 #endif
82 	clint_init_boot_cpu();
83 
84 #ifdef CONFIG_SWIOTLB
85 	swiotlb_init(1);
86 #endif
87 
88 #ifdef CONFIG_KASAN
89 	kasan_init();
90 #endif
91 
92 #if IS_ENABLED(CONFIG_RISCV_SBI)
93 	sbi_init();
94 #endif
95 
96 #ifdef CONFIG_SMP
97 	setup_smp();
98 #endif
99 
100 	riscv_fill_hwcap();
101 }
102 
103 static int __init topology_init(void)
104 {
105 	int i;
106 
107 	for_each_possible_cpu(i) {
108 		struct cpu *cpu = &per_cpu(cpu_devices, i);
109 
110 		cpu->hotpluggable = cpu_has_hotplug(i);
111 		register_cpu(cpu, i);
112 	}
113 
114 	return 0;
115 }
116 subsys_initcall(topology_init);
117