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