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_HVC_RISCV_SBI 42 #include <asm/hvc_riscv_sbi.h> 43 #endif 44 45 #ifdef CONFIG_DUMMY_CONSOLE 46 struct screen_info screen_info = { 47 .orig_video_lines = 30, 48 .orig_video_cols = 80, 49 .orig_video_mode = 0, 50 .orig_video_ega_bx = 0, 51 .orig_video_isVGA = 1, 52 .orig_video_points = 8 53 }; 54 #endif 55 56 #ifdef CONFIG_CMDLINE_BOOL 57 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE; 58 #endif /* CONFIG_CMDLINE_BOOL */ 59 60 unsigned long va_pa_offset; 61 EXPORT_SYMBOL(va_pa_offset); 62 unsigned long pfn_base; 63 EXPORT_SYMBOL(pfn_base); 64 65 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 66 EXPORT_SYMBOL(empty_zero_page); 67 68 /* The lucky hart to first increment this variable will boot the other cores */ 69 atomic_t hart_lottery; 70 71 #ifdef CONFIG_BLK_DEV_INITRD 72 static void __init setup_initrd(void) 73 { 74 extern char __initramfs_start[]; 75 extern unsigned long __initramfs_size; 76 unsigned long size; 77 78 if (__initramfs_size > 0) { 79 initrd_start = (unsigned long)(&__initramfs_start); 80 initrd_end = initrd_start + __initramfs_size; 81 } 82 83 if (initrd_start >= initrd_end) { 84 printk(KERN_INFO "initrd not found or empty"); 85 goto disable; 86 } 87 if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) { 88 printk(KERN_ERR "initrd extends beyond end of memory"); 89 goto disable; 90 } 91 92 size = initrd_end - initrd_start; 93 memblock_reserve(__pa(initrd_start), size); 94 initrd_below_start_ok = 1; 95 96 printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n", 97 (void *)(initrd_start), size); 98 return; 99 disable: 100 pr_cont(" - disabling initrd\n"); 101 initrd_start = 0; 102 initrd_end = 0; 103 } 104 #endif /* CONFIG_BLK_DEV_INITRD */ 105 106 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 107 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 108 109 #ifndef __PAGETABLE_PMD_FOLDED 110 #define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT) 111 pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss; 112 pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 113 #endif 114 115 asmlinkage void __init setup_vm(void) 116 { 117 extern char _start; 118 uintptr_t i; 119 uintptr_t pa = (uintptr_t) &_start; 120 pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC); 121 122 va_pa_offset = PAGE_OFFSET - pa; 123 pfn_base = PFN_DOWN(pa); 124 125 /* Sanity check alignment and size */ 126 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 127 BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0); 128 129 #ifndef __PAGETABLE_PMD_FOLDED 130 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = 131 pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd), 132 __pgprot(_PAGE_TABLE)); 133 trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot); 134 135 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { 136 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; 137 swapper_pg_dir[o] = 138 pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i, 139 __pgprot(_PAGE_TABLE)); 140 } 141 for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++) 142 swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot); 143 #else 144 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = 145 pfn_pgd(PFN_DOWN(pa), prot); 146 147 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { 148 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; 149 swapper_pg_dir[o] = 150 pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot); 151 } 152 #endif 153 } 154 155 void __init sbi_save(unsigned int hartid, void *dtb) 156 { 157 early_init_dt_scan(__va(dtb)); 158 } 159 160 /* 161 * Allow the user to manually add a memory region (in case DTS is broken); 162 * "mem_end=nn[KkMmGg]" 163 */ 164 static int __init mem_end_override(char *p) 165 { 166 resource_size_t base, end; 167 168 if (!p) 169 return -EINVAL; 170 base = (uintptr_t) __pa(PAGE_OFFSET); 171 end = memparse(p, &p) & PMD_MASK; 172 if (end == 0) 173 return -EINVAL; 174 memblock_add(base, end - base); 175 return 0; 176 } 177 early_param("mem_end", mem_end_override); 178 179 static void __init setup_bootmem(void) 180 { 181 struct memblock_region *reg; 182 phys_addr_t mem_size = 0; 183 184 /* Find the memory region containing the kernel */ 185 for_each_memblock(memory, reg) { 186 phys_addr_t vmlinux_end = __pa(_end); 187 phys_addr_t end = reg->base + reg->size; 188 189 if (reg->base <= vmlinux_end && vmlinux_end <= end) { 190 /* 191 * Reserve from the start of the region to the end of 192 * the kernel 193 */ 194 memblock_reserve(reg->base, vmlinux_end - reg->base); 195 mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET); 196 } 197 } 198 BUG_ON(mem_size == 0); 199 200 set_max_mapnr(PFN_DOWN(mem_size)); 201 max_low_pfn = pfn_base + PFN_DOWN(mem_size); 202 203 #ifdef CONFIG_BLK_DEV_INITRD 204 setup_initrd(); 205 #endif /* CONFIG_BLK_DEV_INITRD */ 206 207 early_init_fdt_reserve_self(); 208 early_init_fdt_scan_reserved_mem(); 209 memblock_allow_resize(); 210 memblock_dump_all(); 211 } 212 213 void __init setup_arch(char **cmdline_p) 214 { 215 #if defined(CONFIG_HVC_RISCV_SBI) 216 if (likely(early_console == NULL)) { 217 early_console = &riscv_sbi_early_console_dev; 218 register_console(early_console); 219 } 220 #endif 221 222 #ifdef CONFIG_CMDLINE_BOOL 223 #ifdef CONFIG_CMDLINE_OVERRIDE 224 strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE); 225 #else 226 if (builtin_cmdline[0] != '\0') { 227 /* Append bootloader command line to built-in */ 228 strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE); 229 strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE); 230 strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE); 231 } 232 #endif /* CONFIG_CMDLINE_OVERRIDE */ 233 #endif /* CONFIG_CMDLINE_BOOL */ 234 *cmdline_p = boot_command_line; 235 236 parse_early_param(); 237 238 init_mm.start_code = (unsigned long) _stext; 239 init_mm.end_code = (unsigned long) _etext; 240 init_mm.end_data = (unsigned long) _edata; 241 init_mm.brk = (unsigned long) _end; 242 243 setup_bootmem(); 244 paging_init(); 245 unflatten_device_tree(); 246 247 #ifdef CONFIG_SMP 248 setup_smp(); 249 #endif 250 251 #ifdef CONFIG_DUMMY_CONSOLE 252 conswitchp = &dummy_con; 253 #endif 254 255 riscv_fill_hwcap(); 256 } 257 258 static int __init riscv_device_init(void) 259 { 260 return of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); 261 } 262 subsys_initcall_sync(riscv_device_init); 263