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 unsigned long va_pa_offset; 53 EXPORT_SYMBOL(va_pa_offset); 54 unsigned long pfn_base; 55 EXPORT_SYMBOL(pfn_base); 56 57 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; 58 EXPORT_SYMBOL(empty_zero_page); 59 60 /* The lucky hart to first increment this variable will boot the other cores */ 61 atomic_t hart_lottery; 62 63 #ifdef CONFIG_BLK_DEV_INITRD 64 static void __init setup_initrd(void) 65 { 66 extern char __initramfs_start[]; 67 extern unsigned long __initramfs_size; 68 unsigned long size; 69 70 if (__initramfs_size > 0) { 71 initrd_start = (unsigned long)(&__initramfs_start); 72 initrd_end = initrd_start + __initramfs_size; 73 } 74 75 if (initrd_start >= initrd_end) { 76 printk(KERN_INFO "initrd not found or empty"); 77 goto disable; 78 } 79 if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) { 80 printk(KERN_ERR "initrd extends beyond end of memory"); 81 goto disable; 82 } 83 84 size = initrd_end - initrd_start; 85 memblock_reserve(__pa(initrd_start), size); 86 initrd_below_start_ok = 1; 87 88 printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n", 89 (void *)(initrd_start), size); 90 return; 91 disable: 92 pr_cont(" - disabling initrd\n"); 93 initrd_start = 0; 94 initrd_end = 0; 95 } 96 #endif /* CONFIG_BLK_DEV_INITRD */ 97 98 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 99 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 100 101 #ifndef __PAGETABLE_PMD_FOLDED 102 #define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT) 103 pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss; 104 pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 105 #endif 106 107 asmlinkage void __init setup_vm(void) 108 { 109 extern char _start; 110 uintptr_t i; 111 uintptr_t pa = (uintptr_t) &_start; 112 pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC); 113 114 va_pa_offset = PAGE_OFFSET - pa; 115 pfn_base = PFN_DOWN(pa); 116 117 /* Sanity check alignment and size */ 118 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 119 BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0); 120 121 #ifndef __PAGETABLE_PMD_FOLDED 122 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = 123 pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd), 124 __pgprot(_PAGE_TABLE)); 125 trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot); 126 127 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { 128 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; 129 swapper_pg_dir[o] = 130 pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i, 131 __pgprot(_PAGE_TABLE)); 132 } 133 for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++) 134 swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot); 135 #else 136 trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] = 137 pfn_pgd(PFN_DOWN(pa), prot); 138 139 for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) { 140 size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i; 141 swapper_pg_dir[o] = 142 pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot); 143 } 144 #endif 145 } 146 147 void __init sbi_save(unsigned int hartid, void *dtb) 148 { 149 early_init_dt_scan(__va(dtb)); 150 } 151 152 static void __init setup_bootmem(void) 153 { 154 struct memblock_region *reg; 155 phys_addr_t mem_size = 0; 156 157 /* Find the memory region containing the kernel */ 158 for_each_memblock(memory, reg) { 159 phys_addr_t vmlinux_end = __pa(_end); 160 phys_addr_t end = reg->base + reg->size; 161 162 if (reg->base <= vmlinux_end && vmlinux_end <= end) { 163 /* 164 * Reserve from the start of the region to the end of 165 * the kernel 166 */ 167 memblock_reserve(reg->base, vmlinux_end - reg->base); 168 mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET); 169 } 170 } 171 BUG_ON(mem_size == 0); 172 173 set_max_mapnr(PFN_DOWN(mem_size)); 174 max_low_pfn = pfn_base + PFN_DOWN(mem_size); 175 176 #ifdef CONFIG_BLK_DEV_INITRD 177 setup_initrd(); 178 #endif /* CONFIG_BLK_DEV_INITRD */ 179 180 early_init_fdt_reserve_self(); 181 early_init_fdt_scan_reserved_mem(); 182 memblock_allow_resize(); 183 memblock_dump_all(); 184 185 for_each_memblock(memory, reg) { 186 unsigned long start_pfn = memblock_region_memory_base_pfn(reg); 187 unsigned long end_pfn = memblock_region_memory_end_pfn(reg); 188 189 memblock_set_node(PFN_PHYS(start_pfn), 190 PFN_PHYS(end_pfn - start_pfn), 191 &memblock.memory, 0); 192 } 193 } 194 195 void __init setup_arch(char **cmdline_p) 196 { 197 *cmdline_p = boot_command_line; 198 199 parse_early_param(); 200 201 init_mm.start_code = (unsigned long) _stext; 202 init_mm.end_code = (unsigned long) _etext; 203 init_mm.end_data = (unsigned long) _edata; 204 init_mm.brk = (unsigned long) _end; 205 206 setup_bootmem(); 207 paging_init(); 208 unflatten_device_tree(); 209 210 #ifdef CONFIG_SMP 211 setup_smp(); 212 #endif 213 214 #ifdef CONFIG_DUMMY_CONSOLE 215 conswitchp = &dummy_con; 216 #endif 217 218 riscv_fill_hwcap(); 219 } 220 221 static int __init riscv_device_init(void) 222 { 223 return of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL); 224 } 225 subsys_initcall_sync(riscv_device_init); 226