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 33 #include <asm/setup.h> 34 #include <asm/sections.h> 35 #include <asm/pgtable.h> 36 #include <asm/smp.h> 37 #include <asm/sbi.h> 38 #include <asm/tlbflush.h> 39 #include <asm/thread_info.h> 40 41 #ifdef CONFIG_DUMMY_CONSOLE 42 struct screen_info screen_info = { 43 .orig_video_lines = 30, 44 .orig_video_cols = 80, 45 .orig_video_mode = 0, 46 .orig_video_ega_bx = 0, 47 .orig_video_isVGA = 1, 48 .orig_video_points = 8 49 }; 50 #endif 51 52 #ifdef CONFIG_CMDLINE_BOOL 53 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE; 54 #endif /* CONFIG_CMDLINE_BOOL */ 55 56 unsigned long va_pa_offset; 57 EXPORT_SYMBOL(va_pa_offset); 58 unsigned long pfn_base; 59 EXPORT_SYMBOL(pfn_base); 60 61 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 62 EXPORT_SYMBOL(empty_zero_page); 63 64 /* The lucky hart to first increment this variable will boot the other cores */ 65 atomic_t hart_lottery; 66 67 #ifdef CONFIG_BLK_DEV_INITRD 68 static void __init setup_initrd(void) 69 { 70 extern char __initramfs_start[]; 71 extern unsigned long __initramfs_size; 72 unsigned long size; 73 74 if (__initramfs_size > 0) { 75 initrd_start = (unsigned long)(&__initramfs_start); 76 initrd_end = initrd_start + __initramfs_size; 77 } 78 79 if (initrd_start >= initrd_end) { 80 printk(KERN_INFO "initrd not found or empty"); 81 goto disable; 82 } 83 if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) { 84 printk(KERN_ERR "initrd extends beyond end of memory"); 85 goto disable; 86 } 87 88 size = initrd_end - initrd_start; 89 memblock_reserve(__pa(initrd_start), size); 90 initrd_below_start_ok = 1; 91 92 printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n", 93 (void *)(initrd_start), size); 94 return; 95 disable: 96 pr_cont(" - disabling initrd\n"); 97 initrd_start = 0; 98 initrd_end = 0; 99 } 100 #endif /* CONFIG_BLK_DEV_INITRD */ 101 102 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 103 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 104 105 #ifndef __PAGETABLE_PMD_FOLDED 106 #define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT) 107 pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss; 108 pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 109 #endif 110 111 asmlinkage void __init setup_vm(void) 112 { 113 extern char _start; 114 uintptr_t i; 115 uintptr_t pa = (uintptr_t) &_start; 116 pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC); 117 118 va_pa_offset = PAGE_OFFSET - pa; 119 pfn_base = PFN_DOWN(pa); 120 121 /* Sanity check alignment and size */ 122 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 123 BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0); 124 125 #ifndef __PAGETABLE_PMD_FOLDED 126 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = 127 pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd), 128 __pgprot(_PAGE_TABLE)); 129 trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot); 130 131 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { 132 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; 133 swapper_pg_dir[o] = 134 pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i, 135 __pgprot(_PAGE_TABLE)); 136 } 137 for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++) 138 swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot); 139 #else 140 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = 141 pfn_pgd(PFN_DOWN(pa), prot); 142 143 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { 144 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; 145 swapper_pg_dir[o] = 146 pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot); 147 } 148 #endif 149 } 150 151 void __init sbi_save(unsigned int hartid, void *dtb) 152 { 153 early_init_dt_scan(__va(dtb)); 154 } 155 156 /* 157 * Allow the user to manually add a memory region (in case DTS is broken); 158 * "mem_end=nn[KkMmGg]" 159 */ 160 static int __init mem_end_override(char *p) 161 { 162 resource_size_t base, end; 163 164 if (!p) 165 return -EINVAL; 166 base = (uintptr_t) __pa(PAGE_OFFSET); 167 end = memparse(p, &p) & PMD_MASK; 168 if (end == 0) 169 return -EINVAL; 170 memblock_add(base, end - base); 171 return 0; 172 } 173 early_param("mem_end", mem_end_override); 174 175 static void __init setup_bootmem(void) 176 { 177 struct memblock_region *reg; 178 phys_addr_t mem_size = 0; 179 180 /* Find the memory region containing the kernel */ 181 for_each_memblock(memory, reg) { 182 phys_addr_t vmlinux_end = __pa(_end); 183 phys_addr_t end = reg->base + reg->size; 184 185 if (reg->base <= vmlinux_end && vmlinux_end <= end) { 186 /* 187 * Reserve from the start of the region to the end of 188 * the kernel 189 */ 190 memblock_reserve(reg->base, vmlinux_end - reg->base); 191 mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET); 192 } 193 } 194 BUG_ON(mem_size == 0); 195 196 set_max_mapnr(PFN_DOWN(mem_size)); 197 max_low_pfn = pfn_base + PFN_DOWN(mem_size); 198 199 #ifdef CONFIG_BLK_DEV_INITRD 200 setup_initrd(); 201 #endif /* CONFIG_BLK_DEV_INITRD */ 202 203 early_init_fdt_reserve_self(); 204 early_init_fdt_scan_reserved_mem(); 205 memblock_allow_resize(); 206 memblock_dump_all(); 207 } 208 209 void __init setup_arch(char **cmdline_p) 210 { 211 #ifdef CONFIG_CMDLINE_BOOL 212 #ifdef CONFIG_CMDLINE_OVERRIDE 213 strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE); 214 #else 215 if (builtin_cmdline[0] != '\0') { 216 /* Append bootloader command line to built-in */ 217 strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE); 218 strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE); 219 strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE); 220 } 221 #endif /* CONFIG_CMDLINE_OVERRIDE */ 222 #endif /* CONFIG_CMDLINE_BOOL */ 223 *cmdline_p = boot_command_line; 224 225 parse_early_param(); 226 227 init_mm.start_code = (unsigned long) _stext; 228 init_mm.end_code = (unsigned long) _etext; 229 init_mm.end_data = (unsigned long) _edata; 230 init_mm.brk = (unsigned long) _end; 231 232 setup_bootmem(); 233 paging_init(); 234 unflatten_device_tree(); 235 236 #ifdef CONFIG_SMP 237 setup_smp(); 238 #endif 239 240 #ifdef CONFIG_DUMMY_CONSOLE 241 conswitchp = &dummy_con; 242 #endif 243 244 riscv_fill_hwcap(); 245 } 246 247 static int __init riscv_device_init(void) 248 { 249 return of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); 250 } 251 subsys_initcall_sync(riscv_device_init); 252