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-map-ops.h> |
11 | #include <asm/sections.h> |
12 | #include <asm/mmu_context.h> |
13 | #include <asm/pgalloc.h> |
14 | |
15 | static void __init csky_memblock_init(void) |
16 | { |
17 | unsigned long lowmem_size = PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET); |
18 | unsigned long sseg_size = PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET); |
19 | unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 }; |
20 | signed long size; |
21 | |
22 | memblock_reserve(__pa(_start), _end - _start); |
23 | |
24 | early_init_fdt_reserve_self(); |
25 | early_init_fdt_scan_reserved_mem(); |
26 | |
27 | memblock_dump_all(); |
28 | |
29 | min_low_pfn = PFN_UP(memblock_start_of_DRAM()); |
30 | max_low_pfn = max_pfn = PFN_DOWN(memblock_end_of_DRAM()); |
31 | |
32 | size = max_pfn - min_low_pfn; |
33 | |
34 | if (size >= lowmem_size) { |
35 | max_low_pfn = min_low_pfn + lowmem_size; |
36 | #ifdef CONFIG_PAGE_OFFSET_80000000 |
37 | write_mmu_msa1(read_mmu_msa0() + SSEG_SIZE); |
38 | #endif |
39 | } else if (size > sseg_size) { |
40 | max_low_pfn = min_low_pfn + sseg_size; |
41 | } |
42 | |
43 | max_zone_pfn[ZONE_NORMAL] = max_low_pfn; |
44 | |
45 | mmu_init(min_low_pfn, max_low_pfn); |
46 | |
47 | #ifdef CONFIG_HIGHMEM |
48 | max_zone_pfn[ZONE_HIGHMEM] = max_pfn; |
49 | |
50 | highstart_pfn = max_low_pfn; |
51 | highend_pfn = max_pfn; |
52 | #endif |
53 | memblock_set_current_limit(PFN_PHYS(max_low_pfn)); |
54 | |
55 | dma_contiguous_reserve(addr_limit: 0); |
56 | |
57 | free_area_init(max_zone_pfn); |
58 | } |
59 | |
60 | void __init setup_arch(char **cmdline_p) |
61 | { |
62 | *cmdline_p = boot_command_line; |
63 | |
64 | console_verbose(); |
65 | |
66 | pr_info("Phys. mem: %ldMB\n" , |
67 | (unsigned long) memblock_phys_mem_size()/1024/1024); |
68 | |
69 | setup_initial_init_mm(start_code: _start, end_code: _etext, end_data: _edata, brk: _end); |
70 | |
71 | parse_early_param(); |
72 | |
73 | csky_memblock_init(); |
74 | |
75 | unflatten_and_copy_device_tree(); |
76 | |
77 | #ifdef CONFIG_SMP |
78 | setup_smp(); |
79 | #endif |
80 | |
81 | sparse_init(); |
82 | |
83 | fixaddr_init(); |
84 | |
85 | #ifdef CONFIG_HIGHMEM |
86 | kmap_init(); |
87 | #endif |
88 | } |
89 | |
90 | unsigned long va_pa_offset; |
91 | EXPORT_SYMBOL(va_pa_offset); |
92 | |
93 | static inline unsigned long read_mmu_msa(void) |
94 | { |
95 | #ifdef CONFIG_PAGE_OFFSET_80000000 |
96 | return read_mmu_msa0(); |
97 | #endif |
98 | |
99 | #ifdef CONFIG_PAGE_OFFSET_A0000000 |
100 | return read_mmu_msa1(); |
101 | #endif |
102 | } |
103 | |
104 | asmlinkage __visible void __init csky_start(unsigned int unused, |
105 | void *dtb_start) |
106 | { |
107 | /* Clean up bss section */ |
108 | memset(__bss_start, 0, __bss_stop - __bss_start); |
109 | |
110 | va_pa_offset = read_mmu_msa() & ~(SSEG_SIZE - 1); |
111 | |
112 | pre_trap_init(); |
113 | |
114 | if (dtb_start == NULL) |
115 | early_init_dt_scan(params: __dtb_start); |
116 | else |
117 | early_init_dt_scan(params: dtb_start); |
118 | |
119 | start_kernel(); |
120 | |
121 | asm volatile("br .\n" ); |
122 | } |
123 | |