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