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 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 86 static void __init setup_initrd(void) 87 { 88 extern char __initramfs_start[]; 89 extern unsigned long __initramfs_size; 90 unsigned long size; 91 92 if (__initramfs_size > 0) { 93 initrd_start = (unsigned long)(&__initramfs_start); 94 initrd_end = initrd_start + __initramfs_size; 95 } 96 97 if (initrd_start >= initrd_end) { 98 printk(KERN_INFO "initrd not found or empty"); 99 goto disable; 100 } 101 if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) { 102 printk(KERN_ERR "initrd extends beyond end of memory"); 103 goto disable; 104 } 105 106 size = initrd_end - initrd_start; 107 memblock_reserve(__pa(initrd_start), size); 108 initrd_below_start_ok = 1; 109 110 printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n", 111 (void *)(initrd_start), size); 112 return; 113 disable: 114 pr_cont(" - disabling initrd\n"); 115 initrd_start = 0; 116 initrd_end = 0; 117 } 118 #endif /* CONFIG_BLK_DEV_INITRD */ 119 120 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 121 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 122 123 #ifndef __PAGETABLE_PMD_FOLDED 124 #define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT) 125 pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss; 126 pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 127 #endif 128 129 asmlinkage void __init setup_vm(void) 130 { 131 extern char _start; 132 uintptr_t i; 133 uintptr_t pa = (uintptr_t) &_start; 134 pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC); 135 136 va_pa_offset = PAGE_OFFSET - pa; 137 pfn_base = PFN_DOWN(pa); 138 139 /* Sanity check alignment and size */ 140 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 141 BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0); 142 143 #ifndef __PAGETABLE_PMD_FOLDED 144 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = 145 pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd), 146 __pgprot(_PAGE_TABLE)); 147 trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot); 148 149 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { 150 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; 151 swapper_pg_dir[o] = 152 pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i, 153 __pgprot(_PAGE_TABLE)); 154 } 155 for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++) 156 swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot); 157 #else 158 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = 159 pfn_pgd(PFN_DOWN(pa), prot); 160 161 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { 162 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; 163 swapper_pg_dir[o] = 164 pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot); 165 } 166 #endif 167 } 168 169 void __init parse_dtb(unsigned int hartid, void *dtb) 170 { 171 early_init_dt_scan(__va(dtb)); 172 } 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 for_each_memblock(memory, reg) { 208 unsigned long start_pfn = memblock_region_memory_base_pfn(reg); 209 unsigned long end_pfn = memblock_region_memory_end_pfn(reg); 210 211 memblock_set_node(PFN_PHYS(start_pfn), 212 PFN_PHYS(end_pfn - start_pfn), 213 &memblock.memory, 0); 214 } 215 } 216 217 void __init setup_arch(char **cmdline_p) 218 { 219 #if defined(CONFIG_EARLY_PRINTK) 220 if (likely(early_console == NULL)) { 221 early_console = &riscv_sbi_early_console_dev; 222 register_console(early_console); 223 } 224 #endif 225 *cmdline_p = boot_command_line; 226 227 parse_early_param(); 228 229 init_mm.start_code = (unsigned long) _stext; 230 init_mm.end_code = (unsigned long) _etext; 231 init_mm.end_data = (unsigned long) _edata; 232 init_mm.brk = (unsigned long) _end; 233 234 setup_bootmem(); 235 paging_init(); 236 unflatten_device_tree(); 237 swiotlb_init(1); 238 239 #ifdef CONFIG_SMP 240 setup_smp(); 241 #endif 242 243 #ifdef CONFIG_DUMMY_CONSOLE 244 conswitchp = &dummy_con; 245 #endif 246 247 riscv_fill_hwcap(); 248 } 249 250