1 /*
2 * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
3 * Chen Liqin <liqin.chen@sunplusct.com>
4 * Lennox Wu <lennox.wu@sunplusct.com>
5 * Copyright (C) 2012 Regents of the University of California
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, see the file COPYING, or write
19 * to the Free Software Foundation, Inc.,
20 */
21
22 #include <linux/init.h>
23 #include <linux/mm.h>
24 #include <linux/memblock.h>
25 #include <linux/sched.h>
26 #include <linux/initrd.h>
27 #include <linux/console.h>
28 #include <linux/screen_info.h>
29 #include <linux/of_fdt.h>
30 #include <linux/of_platform.h>
31 #include <linux/sched/task.h>
32 #include <linux/swiotlb.h>
33
34 #include <asm/setup.h>
35 #include <asm/sections.h>
36 #include <asm/pgtable.h>
37 #include <asm/smp.h>
38 #include <asm/sbi.h>
39 #include <asm/tlbflush.h>
40 #include <asm/thread_info.h>
41
42 #ifdef CONFIG_EARLY_PRINTK
sbi_console_write(struct console * co,const char * buf,unsigned int n)43 static void sbi_console_write(struct console *co, const char *buf,
44 unsigned int n)
45 {
46 int i;
47
48 for (i = 0; i < n; ++i) {
49 if (buf[i] == '\n')
50 sbi_console_putchar('\r');
51 sbi_console_putchar(buf[i]);
52 }
53 }
54
55 struct console riscv_sbi_early_console_dev __initdata = {
56 .name = "early",
57 .write = sbi_console_write,
58 .flags = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
59 .index = -1
60 };
61 #endif
62
63 #ifdef CONFIG_DUMMY_CONSOLE
64 struct screen_info screen_info = {
65 .orig_video_lines = 30,
66 .orig_video_cols = 80,
67 .orig_video_mode = 0,
68 .orig_video_ega_bx = 0,
69 .orig_video_isVGA = 1,
70 .orig_video_points = 8
71 };
72 #endif
73
74 unsigned long va_pa_offset;
75 EXPORT_SYMBOL(va_pa_offset);
76 unsigned long pfn_base;
77 EXPORT_SYMBOL(pfn_base);
78
79 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
80 EXPORT_SYMBOL(empty_zero_page);
81
82 /* The lucky hart to first increment this variable will boot the other cores */
83 atomic_t hart_lottery;
84
85 #ifdef CONFIG_BLK_DEV_INITRD
setup_initrd(void)86 static void __init setup_initrd(void)
87 {
88 unsigned long size;
89
90 if (initrd_start >= initrd_end) {
91 printk(KERN_INFO "initrd not found or empty");
92 goto disable;
93 }
94 if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
95 printk(KERN_ERR "initrd extends beyond end of memory");
96 goto disable;
97 }
98
99 size = initrd_end - initrd_start;
100 memblock_reserve(__pa(initrd_start), size);
101 initrd_below_start_ok = 1;
102
103 printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n",
104 (void *)(initrd_start), size);
105 return;
106 disable:
107 pr_cont(" - disabling initrd\n");
108 initrd_start = 0;
109 initrd_end = 0;
110 }
111 #endif /* CONFIG_BLK_DEV_INITRD */
112
113 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
114 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
115
116 #ifndef __PAGETABLE_PMD_FOLDED
117 #define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT)
118 pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss;
119 pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
120 #endif
121
setup_vm(void)122 asmlinkage void __init setup_vm(void)
123 {
124 extern char _start;
125 uintptr_t i;
126 uintptr_t pa = (uintptr_t) &_start;
127 pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC);
128
129 va_pa_offset = PAGE_OFFSET - pa;
130 pfn_base = PFN_DOWN(pa);
131
132 /* Sanity check alignment and size */
133 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
134 BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0);
135
136 #ifndef __PAGETABLE_PMD_FOLDED
137 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
138 pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd),
139 __pgprot(_PAGE_TABLE));
140 trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot);
141
142 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
143 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
144 swapper_pg_dir[o] =
145 pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i,
146 __pgprot(_PAGE_TABLE));
147 }
148 for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++)
149 swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot);
150 #else
151 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
152 pfn_pgd(PFN_DOWN(pa), prot);
153
154 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
155 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
156 swapper_pg_dir[o] =
157 pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot);
158 }
159 #endif
160 }
161
parse_dtb(unsigned int hartid,void * dtb)162 void __init parse_dtb(unsigned int hartid, void *dtb)
163 {
164 early_init_dt_scan(__va(dtb));
165 }
166
setup_bootmem(void)167 static void __init setup_bootmem(void)
168 {
169 struct memblock_region *reg;
170 phys_addr_t mem_size = 0;
171
172 /* Find the memory region containing the kernel */
173 for_each_memblock(memory, reg) {
174 phys_addr_t vmlinux_end = __pa(_end);
175 phys_addr_t end = reg->base + reg->size;
176
177 if (reg->base <= vmlinux_end && vmlinux_end <= end) {
178 /*
179 * Reserve from the start of the region to the end of
180 * the kernel
181 */
182 memblock_reserve(reg->base, vmlinux_end - reg->base);
183 mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
184 }
185 }
186 BUG_ON(mem_size == 0);
187
188 set_max_mapnr(PFN_DOWN(mem_size));
189 max_low_pfn = memblock_end_of_DRAM();
190
191 #ifdef CONFIG_BLK_DEV_INITRD
192 setup_initrd();
193 #endif /* CONFIG_BLK_DEV_INITRD */
194
195 early_init_fdt_reserve_self();
196 early_init_fdt_scan_reserved_mem();
197 memblock_allow_resize();
198 memblock_dump_all();
199
200 for_each_memblock(memory, reg) {
201 unsigned long start_pfn = memblock_region_memory_base_pfn(reg);
202 unsigned long end_pfn = memblock_region_memory_end_pfn(reg);
203
204 memblock_set_node(PFN_PHYS(start_pfn),
205 PFN_PHYS(end_pfn - start_pfn),
206 &memblock.memory, 0);
207 }
208 }
209
setup_arch(char ** cmdline_p)210 void __init setup_arch(char **cmdline_p)
211 {
212 #if defined(CONFIG_EARLY_PRINTK)
213 if (likely(early_console == NULL)) {
214 early_console = &riscv_sbi_early_console_dev;
215 register_console(early_console);
216 }
217 #endif
218 *cmdline_p = boot_command_line;
219
220 parse_early_param();
221
222 init_mm.start_code = (unsigned long) _stext;
223 init_mm.end_code = (unsigned long) _etext;
224 init_mm.end_data = (unsigned long) _edata;
225 init_mm.brk = (unsigned long) _end;
226
227 setup_bootmem();
228 paging_init();
229 unflatten_device_tree();
230 swiotlb_init(1);
231
232 #ifdef CONFIG_SMP
233 setup_smp();
234 #endif
235
236 #ifdef CONFIG_DUMMY_CONSOLE
237 conswitchp = &dummy_con;
238 #endif
239
240 riscv_fill_hwcap();
241 }
242
243
