Ley Foon Tan | 27d2241 | 2014-11-06 15:19:37 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Nios2-specific parts of system setup |
| 3 | * |
| 4 | * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> |
| 5 | * Copyright (C) 2004 Microtronix Datacom Ltd. |
| 6 | * Copyright (C) 2001 Vic Phillips <vic@microtronix.com> |
| 7 | * |
| 8 | * This file is subject to the terms and conditions of the GNU General Public |
| 9 | * License. See the file "COPYING" in the main directory of this archive |
| 10 | * for more details. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/export.h> |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/mm.h> |
| 16 | #include <linux/sched.h> |
| 17 | #include <linux/console.h> |
| 18 | #include <linux/bootmem.h> |
| 19 | #include <linux/initrd.h> |
| 20 | #include <linux/of_fdt.h> |
| 21 | |
| 22 | #include <asm/mmu_context.h> |
| 23 | #include <asm/sections.h> |
| 24 | #include <asm/setup.h> |
| 25 | #include <asm/cpuinfo.h> |
| 26 | |
| 27 | unsigned long memory_start; |
| 28 | EXPORT_SYMBOL(memory_start); |
| 29 | |
| 30 | unsigned long memory_end; |
| 31 | EXPORT_SYMBOL(memory_end); |
| 32 | |
| 33 | unsigned long memory_size; |
| 34 | |
| 35 | static struct pt_regs fake_regs = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 36 | 0, 0, 0, 0, 0, 0, |
| 37 | 0}; |
| 38 | |
| 39 | /* Copy a short hook instruction sequence to the exception address */ |
| 40 | static inline void copy_exception_handler(unsigned int addr) |
| 41 | { |
| 42 | unsigned int start = (unsigned int) exception_handler_hook; |
| 43 | volatile unsigned int tmp = 0; |
| 44 | |
| 45 | if (start == addr) { |
| 46 | /* The CPU exception address already points to the handler. */ |
| 47 | return; |
| 48 | } |
| 49 | |
| 50 | __asm__ __volatile__ ( |
| 51 | "ldw %2,0(%0)\n" |
| 52 | "stw %2,0(%1)\n" |
| 53 | "ldw %2,4(%0)\n" |
| 54 | "stw %2,4(%1)\n" |
| 55 | "ldw %2,8(%0)\n" |
| 56 | "stw %2,8(%1)\n" |
| 57 | "flushd 0(%1)\n" |
| 58 | "flushd 4(%1)\n" |
| 59 | "flushd 8(%1)\n" |
| 60 | "flushi %1\n" |
| 61 | "addi %1,%1,4\n" |
| 62 | "flushi %1\n" |
| 63 | "addi %1,%1,4\n" |
| 64 | "flushi %1\n" |
| 65 | "flushp\n" |
| 66 | : /* no output registers */ |
| 67 | : "r" (start), "r" (addr), "r" (tmp) |
| 68 | : "memory" |
| 69 | ); |
| 70 | } |
| 71 | |
| 72 | /* Copy the fast TLB miss handler */ |
| 73 | static inline void copy_fast_tlb_miss_handler(unsigned int addr) |
| 74 | { |
| 75 | unsigned int start = (unsigned int) fast_handler; |
| 76 | unsigned int end = (unsigned int) fast_handler_end; |
| 77 | volatile unsigned int tmp = 0; |
| 78 | |
| 79 | __asm__ __volatile__ ( |
| 80 | "1:\n" |
| 81 | " ldw %3,0(%0)\n" |
| 82 | " stw %3,0(%1)\n" |
| 83 | " flushd 0(%1)\n" |
| 84 | " flushi %1\n" |
| 85 | " flushp\n" |
| 86 | " addi %0,%0,4\n" |
| 87 | " addi %1,%1,4\n" |
| 88 | " bne %0,%2,1b\n" |
| 89 | : /* no output registers */ |
| 90 | : "r" (start), "r" (addr), "r" (end), "r" (tmp) |
| 91 | : "memory" |
| 92 | ); |
| 93 | } |
| 94 | |
| 95 | /* |
| 96 | * save args passed from u-boot, called from head.S |
| 97 | * |
| 98 | * @r4: NIOS magic |
| 99 | * @r5: initrd start |
| 100 | * @r6: initrd end or fdt |
| 101 | * @r7: kernel command line |
| 102 | */ |
| 103 | asmlinkage void __init nios2_boot_init(unsigned r4, unsigned r5, unsigned r6, |
| 104 | unsigned r7) |
| 105 | { |
| 106 | unsigned dtb_passed = 0; |
Marek Vasut | 4db2196 | 2015-09-30 22:06:46 +0800 | [diff] [blame] | 107 | char cmdline_passed[COMMAND_LINE_SIZE] __maybe_unused = { 0, }; |
Ley Foon Tan | 27d2241 | 2014-11-06 15:19:37 +0800 | [diff] [blame] | 108 | |
| 109 | #if defined(CONFIG_NIOS2_PASS_CMDLINE) |
| 110 | if (r4 == 0x534f494e) { /* r4 is magic NIOS */ |
| 111 | #if defined(CONFIG_BLK_DEV_INITRD) |
| 112 | if (r5) { /* initramfs */ |
| 113 | initrd_start = r5; |
| 114 | initrd_end = r6; |
| 115 | } |
| 116 | #endif /* CONFIG_BLK_DEV_INITRD */ |
| 117 | dtb_passed = r6; |
| 118 | |
| 119 | if (r7) |
| 120 | strncpy(cmdline_passed, (char *)r7, COMMAND_LINE_SIZE); |
| 121 | } |
| 122 | #endif |
| 123 | |
| 124 | early_init_devtree((void *)dtb_passed); |
| 125 | |
| 126 | #ifndef CONFIG_CMDLINE_FORCE |
| 127 | if (cmdline_passed[0]) |
| 128 | strncpy(boot_command_line, cmdline_passed, COMMAND_LINE_SIZE); |
| 129 | #ifdef CONFIG_NIOS2_CMDLINE_IGNORE_DTB |
| 130 | else |
| 131 | strncpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE); |
| 132 | #endif |
| 133 | #endif |
| 134 | } |
| 135 | |
| 136 | void __init setup_arch(char **cmdline_p) |
| 137 | { |
| 138 | int bootmap_size; |
| 139 | |
| 140 | console_verbose(); |
| 141 | |
Ley Foon Tan | e8bf5bc | 2015-02-10 23:21:08 +0800 | [diff] [blame] | 142 | #ifdef CONFIG_EARLY_PRINTK |
| 143 | setup_early_printk(); |
| 144 | #endif |
| 145 | |
Ley Foon Tan | 27d2241 | 2014-11-06 15:19:37 +0800 | [diff] [blame] | 146 | memory_start = PAGE_ALIGN((unsigned long)__pa(_end)); |
| 147 | memory_end = (unsigned long) CONFIG_NIOS2_MEM_BASE + memory_size; |
| 148 | |
| 149 | init_mm.start_code = (unsigned long) _stext; |
| 150 | init_mm.end_code = (unsigned long) _etext; |
| 151 | init_mm.end_data = (unsigned long) _edata; |
| 152 | init_mm.brk = (unsigned long) _end; |
| 153 | init_task.thread.kregs = &fake_regs; |
| 154 | |
| 155 | /* Keep a copy of command line */ |
| 156 | *cmdline_p = boot_command_line; |
| 157 | |
| 158 | min_low_pfn = PFN_UP(memory_start); |
| 159 | max_low_pfn = PFN_DOWN(memory_end); |
| 160 | max_mapnr = max_low_pfn; |
| 161 | |
| 162 | /* |
| 163 | * give all the memory to the bootmap allocator, tell it to put the |
| 164 | * boot mem_map at the start of memory |
| 165 | */ |
| 166 | pr_debug("init_bootmem_node(?,%#lx, %#x, %#lx)\n", |
| 167 | min_low_pfn, PFN_DOWN(PHYS_OFFSET), max_low_pfn); |
| 168 | bootmap_size = init_bootmem_node(NODE_DATA(0), |
| 169 | min_low_pfn, PFN_DOWN(PHYS_OFFSET), |
| 170 | max_low_pfn); |
| 171 | |
| 172 | /* |
| 173 | * free the usable memory, we have to make sure we do not free |
| 174 | * the bootmem bitmap so we then reserve it after freeing it :-) |
| 175 | */ |
| 176 | pr_debug("free_bootmem(%#lx, %#lx)\n", |
| 177 | memory_start, memory_end - memory_start); |
| 178 | free_bootmem(memory_start, memory_end - memory_start); |
| 179 | |
| 180 | /* |
| 181 | * Reserve the bootmem bitmap itself as well. We do this in two |
| 182 | * steps (first step was init_bootmem()) because this catches |
| 183 | * the (very unlikely) case of us accidentally initializing the |
| 184 | * bootmem allocator with an invalid RAM area. |
| 185 | * |
| 186 | * Arguments are start, size |
| 187 | */ |
| 188 | pr_debug("reserve_bootmem(%#lx, %#x)\n", memory_start, bootmap_size); |
| 189 | reserve_bootmem(memory_start, bootmap_size, BOOTMEM_DEFAULT); |
| 190 | |
| 191 | #ifdef CONFIG_BLK_DEV_INITRD |
| 192 | if (initrd_start) { |
| 193 | reserve_bootmem(virt_to_phys((void *)initrd_start), |
| 194 | initrd_end - initrd_start, BOOTMEM_DEFAULT); |
| 195 | } |
| 196 | #endif /* CONFIG_BLK_DEV_INITRD */ |
| 197 | |
Tobias Klauser | c1dcea1 | 2017-04-02 20:08:04 -0700 | [diff] [blame] | 198 | early_init_fdt_reserve_self(); |
| 199 | early_init_fdt_scan_reserved_mem(); |
| 200 | |
Ley Foon Tan | 27d2241 | 2014-11-06 15:19:37 +0800 | [diff] [blame] | 201 | unflatten_and_copy_device_tree(); |
| 202 | |
| 203 | setup_cpuinfo(); |
| 204 | |
| 205 | copy_exception_handler(cpuinfo.exception_addr); |
| 206 | |
| 207 | mmu_init(); |
| 208 | |
| 209 | copy_fast_tlb_miss_handler(cpuinfo.fast_tlb_miss_exc_addr); |
| 210 | |
| 211 | /* |
| 212 | * Initialize MMU context handling here because data from cpuinfo is |
| 213 | * needed for this. |
| 214 | */ |
| 215 | mmu_context_init(); |
| 216 | |
| 217 | /* |
| 218 | * get kmalloc into gear |
| 219 | */ |
| 220 | paging_init(); |
| 221 | |
| 222 | #if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE) |
| 223 | conswitchp = &dummy_con; |
| 224 | #endif |
| 225 | } |