xref: /openbmc/linux/arch/csky/kernel/setup.c (revision be709d48)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3 
4 #include <linux/console.h>
5 #include <linux/memblock.h>
6 #include <linux/initrd.h>
7 #include <linux/of.h>
8 #include <linux/of_fdt.h>
9 #include <linux/start_kernel.h>
10 #include <linux/dma-contiguous.h>
11 #include <linux/screen_info.h>
12 #include <asm/sections.h>
13 #include <asm/mmu_context.h>
14 #include <asm/pgalloc.h>
15 
16 #ifdef CONFIG_DUMMY_CONSOLE
17 struct screen_info screen_info = {
18 	.orig_video_lines	= 30,
19 	.orig_video_cols	= 80,
20 	.orig_video_mode	= 0,
21 	.orig_video_ega_bx	= 0,
22 	.orig_video_isVGA	= 1,
23 	.orig_video_points	= 8
24 };
25 #endif
26 
27 phys_addr_t __init_memblock memblock_end_of_REG0(void)
28 {
29 	return (memblock.memory.regions[0].base +
30 		memblock.memory.regions[0].size);
31 }
32 
33 phys_addr_t __init_memblock memblock_start_of_REG1(void)
34 {
35 	return memblock.memory.regions[1].base;
36 }
37 
38 size_t __init_memblock memblock_size_of_REG1(void)
39 {
40 	return memblock.memory.regions[1].size;
41 }
42 
43 static void __init csky_memblock_init(void)
44 {
45 	unsigned long zone_size[MAX_NR_ZONES];
46 	unsigned long zhole_size[MAX_NR_ZONES];
47 	signed long size;
48 
49 	memblock_reserve(__pa(_stext), _end - _stext);
50 #ifdef CONFIG_BLK_DEV_INITRD
51 	memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);
52 #endif
53 
54 	early_init_fdt_reserve_self();
55 	early_init_fdt_scan_reserved_mem();
56 
57 	memblock_dump_all();
58 
59 	memset(zone_size, 0, sizeof(zone_size));
60 	memset(zhole_size, 0, sizeof(zhole_size));
61 
62 	min_low_pfn = PFN_UP(memblock_start_of_DRAM());
63 	max_pfn	    = PFN_DOWN(memblock_end_of_DRAM());
64 
65 	max_low_pfn = PFN_UP(memblock_end_of_REG0());
66 	if (max_low_pfn == 0)
67 		max_low_pfn = max_pfn;
68 
69 	size = max_pfn - min_low_pfn;
70 
71 	if (memblock.memory.cnt > 1) {
72 		zone_size[ZONE_NORMAL]  =
73 			PFN_DOWN(memblock_start_of_REG1()) - min_low_pfn;
74 		zhole_size[ZONE_NORMAL] =
75 			PFN_DOWN(memblock_start_of_REG1()) - max_low_pfn;
76 	} else {
77 		if (size <= PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET))
78 			zone_size[ZONE_NORMAL] = max_pfn - min_low_pfn;
79 		else {
80 			zone_size[ZONE_NORMAL] =
81 				PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
82 			max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
83 		}
84 	}
85 
86 #ifdef CONFIG_HIGHMEM
87 	size = 0;
88 	if (memblock.memory.cnt > 1) {
89 		size = PFN_DOWN(memblock_size_of_REG1());
90 		highstart_pfn = PFN_DOWN(memblock_start_of_REG1());
91 	} else {
92 		size = max_pfn - min_low_pfn -
93 			PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
94 		highstart_pfn =  min_low_pfn +
95 			PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
96 	}
97 
98 	if (size > 0)
99 		zone_size[ZONE_HIGHMEM] = size;
100 
101 	highend_pfn = max_pfn;
102 #endif
103 	memblock_set_current_limit(PFN_PHYS(max_low_pfn));
104 
105 	dma_contiguous_reserve(0);
106 
107 	free_area_init_node(0, zone_size, min_low_pfn, zhole_size);
108 }
109 
110 void __init setup_arch(char **cmdline_p)
111 {
112 	*cmdline_p = boot_command_line;
113 
114 	console_verbose();
115 
116 	pr_info("Phys. mem: %ldMB\n",
117 		(unsigned long) memblock_phys_mem_size()/1024/1024);
118 
119 	init_mm.start_code = (unsigned long) _stext;
120 	init_mm.end_code = (unsigned long) _etext;
121 	init_mm.end_data = (unsigned long) _edata;
122 	init_mm.brk = (unsigned long) _end;
123 
124 	parse_early_param();
125 
126 	csky_memblock_init();
127 
128 	unflatten_and_copy_device_tree();
129 
130 #ifdef CONFIG_SMP
131 	setup_smp();
132 #endif
133 
134 	sparse_init();
135 
136 #ifdef CONFIG_HIGHMEM
137 	kmap_init();
138 #endif
139 
140 #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
141 	conswitchp = &dummy_con;
142 #endif
143 }
144 
145 asmlinkage __visible void __init csky_start(unsigned int unused, void *param)
146 {
147 	/* Clean up bss section */
148 	memset(__bss_start, 0, __bss_stop - __bss_start);
149 
150 	pre_trap_init();
151 	pre_mmu_init();
152 
153 	if (param == NULL)
154 		early_init_dt_scan(__dtb_start);
155 	else
156 		early_init_dt_scan(param);
157 
158 	start_kernel();
159 
160 	asm volatile("br .\n");
161 }
162