1/* 2 * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved. 3 * 4 * SPDX-License-Identifier: GPL-2.0+ 5 */ 6 7#include <asm-offsets.h> 8#include <config.h> 9#include <linux/linkage.h> 10#include <asm/arcregs.h> 11 12/* 13 * Note on the LD/ST addressing modes with address register write-back 14 * 15 * LD.a same as LD.aw 16 * 17 * LD.a reg1, [reg2, x] => Pre Incr 18 * Eff Addr for load = [reg2 + x] 19 * 20 * LD.ab reg1, [reg2, x] => Post Incr 21 * Eff Addr for load = [reg2] 22 */ 23 24.macro PUSH reg 25 st.a \reg, [%sp, -4] 26.endm 27 28.macro PUSHAX aux 29 lr %r9, [\aux] 30 PUSH %r9 31.endm 32 33.macro SAVE_R1_TO_R24 34 PUSH %r1 35 PUSH %r2 36 PUSH %r3 37 PUSH %r4 38 PUSH %r5 39 PUSH %r6 40 PUSH %r7 41 PUSH %r8 42 PUSH %r9 43 PUSH %r10 44 PUSH %r11 45 PUSH %r12 46 PUSH %r13 47 PUSH %r14 48 PUSH %r15 49 PUSH %r16 50 PUSH %r17 51 PUSH %r18 52 PUSH %r19 53 PUSH %r20 54 PUSH %r21 55 PUSH %r22 56 PUSH %r23 57 PUSH %r24 58.endm 59 60.macro SAVE_ALL_SYS 61 /* saving %r0 to reg->r0 in advance since we read %ecr into it */ 62 st %r0, [%sp, -8] 63 lr %r0, [%ecr] /* all stack addressing is manual so far */ 64 st %r0, [%sp] 65 st %sp, [%sp, -4] 66 /* now move %sp to reg->r0 position so we can do "push" automatically */ 67 sub %sp, %sp, 8 68 69 SAVE_R1_TO_R24 70 PUSH %r25 71 PUSH %gp 72 PUSH %fp 73 PUSH %blink 74 PUSHAX %eret 75 PUSHAX %erstatus 76 PUSH %lp_count 77 PUSHAX %lp_end 78 PUSHAX %lp_start 79 PUSHAX %erbta 80.endm 81 82.macro SAVE_EXCEPTION_SOURCE 83#ifdef CONFIG_MMU 84 /* If MMU exists exception faulting address is loaded in EFA reg */ 85 lr %r0, [%efa] 86#else 87 /* Otherwise in ERET (exception return) reg */ 88 lr %r0, [%eret] 89#endif 90.endm 91 92ENTRY(_start) 93 /* Setup interrupt vector base that matches "__text_start" */ 94 sr __ivt_start, [ARC_AUX_INTR_VEC_BASE] 95 96 /* Setup stack pointer */ 97 mov %sp, CONFIG_SYS_INIT_SP_ADDR 98 mov %fp, %sp 99 100 /* Clear bss */ 101 mov %r0, __bss_start 102 mov %r1, __bss_end 103 104clear_bss: 105 st.ab 0, [%r0, 4] 106 brlt %r0, %r1, clear_bss 107 108 /* Zero the one and only argument of "board_init_f" */ 109 mov_s %r0, 0 110 j board_init_f 111ENDPROC(_start) 112 113ENTRY(memory_error) 114 SAVE_ALL_SYS 115 SAVE_EXCEPTION_SOURCE 116 mov %r1, %sp 117 j do_memory_error 118ENDPROC(memory_error) 119 120ENTRY(instruction_error) 121 SAVE_ALL_SYS 122 SAVE_EXCEPTION_SOURCE 123 mov %r1, %sp 124 j do_instruction_error 125ENDPROC(instruction_error) 126 127ENTRY(interrupt_handler) 128 /* Todo - save and restore CPU context when interrupts will be in use */ 129 bl do_interrupt_handler 130 rtie 131ENDPROC(interrupt_handler) 132 133ENTRY(EV_MachineCheck) 134 SAVE_ALL_SYS 135 SAVE_EXCEPTION_SOURCE 136 mov %r1, %sp 137 j do_machine_check_fault 138ENDPROC(EV_MachineCheck) 139 140ENTRY(EV_TLBMissI) 141 SAVE_ALL_SYS 142 mov %r0, %sp 143 j do_itlb_miss 144ENDPROC(EV_TLBMissI) 145 146ENTRY(EV_TLBMissD) 147 SAVE_ALL_SYS 148 mov %r0, %sp 149 j do_dtlb_miss 150ENDPROC(EV_TLBMissD) 151 152ENTRY(EV_TLBProtV) 153 SAVE_ALL_SYS 154 SAVE_EXCEPTION_SOURCE 155 mov %r1, %sp 156 j do_tlb_prot_violation 157ENDPROC(EV_TLBProtV) 158 159ENTRY(EV_PrivilegeV) 160 SAVE_ALL_SYS 161 mov %r0, %sp 162 j do_privilege_violation 163ENDPROC(EV_PrivilegeV) 164 165ENTRY(EV_Trap) 166 SAVE_ALL_SYS 167 mov %r0, %sp 168 j do_trap 169ENDPROC(EV_Trap) 170 171ENTRY(EV_Extension) 172 SAVE_ALL_SYS 173 mov %r0, %sp 174 j do_extension 175ENDPROC(EV_Extension) 176 177/* 178 * void relocate_code (addr_sp, gd, addr_moni) 179 * 180 * This "function" does not return, instead it continues in RAM 181 * after relocating the monitor code. 182 * 183 * r0 = start_addr_sp 184 * r1 = new__gd 185 * r2 = relocaddr 186 */ 187ENTRY(relocate_code) 188 /* 189 * r0-r12 might be clobbered by C functions 190 * so we use r13-r16 for storage here 191 */ 192 mov %r13, %r0 /* save addr_sp */ 193 mov %r14, %r1 /* save addr of gd */ 194 mov %r15, %r2 /* save addr of destination */ 195 196 mov %r16, %r2 /* %r9 - relocation offset */ 197 sub %r16, %r16, __image_copy_start 198 199/* Set up the stack */ 200stack_setup: 201 mov %sp, %r13 202 mov %fp, %sp 203 204/* Check if monitor is loaded right in place for relocation */ 205 mov %r0, __image_copy_start 206 cmp %r0, %r15 /* skip relocation if code loaded */ 207 bz do_board_init_r /* in target location already */ 208 209/* Copy data (__image_copy_start - __image_copy_end) to new location */ 210 mov %r1, %r15 211 mov %r2, __image_copy_end 212 sub %r2, %r2, %r0 /* r3 <- amount of bytes to copy */ 213 asr %r2, %r2, 2 /* r3 <- amount of words to copy */ 214 mov %lp_count, %r2 215 lp copy_end 216 ld.ab %r2,[%r0,4] 217 st.ab %r2,[%r1,4] 218copy_end: 219 220/* Fix relocations related issues */ 221 bl do_elf_reloc_fixups 222#ifndef CONFIG_SYS_ICACHE_OFF 223 bl invalidate_icache_all 224#endif 225#ifndef CONFIG_SYS_DCACHE_OFF 226 bl flush_dcache_all 227#endif 228 229/* Update position of intterupt vector table */ 230 lr %r0, [ARC_AUX_INTR_VEC_BASE] /* Read current position */ 231 add %r0, %r0, %r16 /* Update address */ 232 sr %r0, [ARC_AUX_INTR_VEC_BASE] /* Write new position */ 233 234do_board_init_r: 235/* Prepare for exection of "board_init_r" in relocated monitor */ 236 mov %r2, board_init_r /* old address of "board_init_r()" */ 237 add %r2, %r2, %r16 /* new address of "board_init_r()" */ 238 mov %r0, %r14 /* 1-st parameter: gd_t */ 239 mov %r1, %r15 /* 2-nd parameter: dest_addr */ 240 j [%r2] 241ENDPROC(relocate_code) 242