1/* $NetBSD: start.S,v 1.2 2006/04/22 07:58:53 cherry Exp $ */ 2 3/*- 4 * Copyright (c) 2001 Doug Rabson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD: src/sys/boot/efi/libefi/arch/ia64/start.S,v 1.7 2004/07/20 07:11:14 marcel Exp $ 29 */ 30 31 .text 32 33#include <machine/asm.h> 34 35#define EFI_SUCCESS 0 36#define EFI_LOAD_ERROR 1 37#define EFI_BUFFER_TOO_SMALL 5 38 39#define DT_NULL 0 /* Terminating entry. */ 40#define DT_NEEDED 1 /* String table offset of a needed shared 41 library. */ 42#define DT_PLTRELSZ 2 /* Total size in bytes of PLT relocations. */ 43#define DT_PLTGOT 3 /* Processor-dependent address. */ 44#define DT_HASH 4 /* Address of symbol hash table. */ 45#define DT_STRTAB 5 /* Address of string table. */ 46#define DT_SYMTAB 6 /* Address of symbol table. */ 47#define DT_RELA 7 /* Address of ElfNN_Rela relocations. */ 48#define DT_RELASZ 8 /* Total size of ElfNN_Rela relocations. */ 49#define DT_RELAENT 9 /* Size of each ElfNN_Rela relocation entry. */ 50#define DT_STRSZ 10 /* Size of string table. */ 51#define DT_SYMENT 11 /* Size of each symbol table entry. */ 52#define DT_INIT 12 /* Address of initialization function. */ 53#define DT_FINI 13 /* Address of finalization function. */ 54#define DT_SONAME 14 /* String table offset of shared object 55 name. */ 56#define DT_RPATH 15 /* String table offset of library path. */ 57#define DT_SYMBOLIC 16 /* Indicates "symbolic" linking. */ 58#define DT_REL 17 /* Address of ElfNN_Rel relocations. */ 59#define DT_RELSZ 18 /* Total size of ElfNN_Rel relocations. */ 60#define DT_RELENT 19 /* Size of each ElfNN_Rel relocation. */ 61#define DT_PLTREL 20 /* Type of relocation used for PLT. */ 62#define DT_DEBUG 21 /* Reserved (not used). */ 63#define DT_TEXTREL 22 /* Indicates there may be relocations in 64 non-writable segments. */ 65#define DT_JMPREL 23 /* Address of PLT relocations. */ 66 67#define DT_COUNT 24 /* Number of defined d_tag values. */ 68 69#define R_IA64_NONE 0 /* None */ 70#define R_IA64_DIR64MSB 0x26 /* word64 MSB S + A */ 71#define R_IA64_DIR64LSB 0x27 /* word64 LSB S + A */ 72#define R_IA64_FPTR64MSB 0x46 /* word64 MSB @fptr(S + A) */ 73#define R_IA64_FPTR64LSB 0x47 /* word64 LSB @fptr(S + A) */ 74#define R_IA64_REL64MSB 0x6e /* word64 MSB BD + A */ 75#define R_IA64_REL32LSB 0x6d /* word32 LSB BD + A */ 76#define R_IA64_REL64LSB 0x6f /* word64 LSB BD + A */ 77#define R_IA64_IPLTLSB 0x81 /* function descriptor LSB speciaal */ 78 79ENTRY(_start, 2) 80 alloc loc0=ar.pfs,2,3,3,0 81 mov loc1=rp 82 movl loc2=@gprel(ImageBase) 83 ;; 84 add loc2=gp,loc2 85 ;; 86 mov out0=loc2 87 mov out1=in1 88 ;; 89 br.call.sptk.few rp=_reloc // relocate image 90 91 cmp.ne p6,p0=EFI_SUCCESS,r8 // did it work? 92(p6) br.cond.dpnt.few 9f 93 94 mov out0=in0 // image_handle 95 mov out1=in1 // system_table 96 br.call.sptk.few rp=efi_main 979: 98 mov ar.pfs=loc0 99 mov rp=loc1 100 ;; 101 br.ret.sptk.few rp 102END(_start) 103 104 // PLABEL for PE32+ 105 .section .plabel, "a" 106 .align 16 107 .global _start_plabel 108_start_plabel: 109 data16 @iplt(_start) 110 .previous 111 112 // A PE32+ relocation entry for the plabel 113 .section .reloc, "a" 114 data4 _start_plabel 115 data4 12 116 data2 (10 << 12) + 0 117 data2 (10 << 12) + 8 118 .previous 119 120// in0: image base 121// in1: system table 122// 123// XXX Assumes PLT relocations are of type Elf_Rela 124// 125// r2 = address of fptr_storage 126// r3 = address of fptr_storage_end 127// r4 = address of first free fptr 128// 129// r15 = r_offset 130// r16 = r_info -OR- d_tag 131// r17 = r_addend -OR- d_val (=d_ptr) 132// r18 = address of .rela dynamic section 133// r19 = size of .rela section 134// r20 = size of .rela element (Elf_Rela) 135// r21 = address of first PLT relocation 136// r22 = size of PLT relocations 137// r23 = relocation type 138// r24 = address of symbol 139// r28 = R_IA64_IPLTLSB 140// f8 = address of symbol table 141// f9 = size of symtab element 142 143STATIC_ENTRY(_reloc, 2) 144 alloc loc0=ar.pfs,2,2,0,0 145 ;; 146 mov loc1=rp 147 movl r29=@gprel(_DYNAMIC) // find _DYNAMIC etc. 148 ;; 149 add r15=r29,gp 150 movl r29=@gprel(fptr_storage) 151 ;; 152 add r2=r29,gp 153 movl r29=@gprel(fptr_storage_end) 154 ;; 155 add r3=r29,gp 156 mov r4=r2 157 mov r19=0 158 mov r22=0 159 mov r20=24 160 mov r28=R_IA64_IPLTLSB 161 ;; 1621: 163 ld8 r16=[r15],8 // read r15->d_tag 164 ;; 165 ld8 r17=[r15],8 // and r15->d_val 166 ;; 167 cmp.eq p6,p0=DT_NULL,r16 // done? 168(p6) br.cond.dpnt.few 2f 169 ;; 170 cmp.eq p6,p0=DT_RELA,r16 // rela section? 171 ;; 172(p6) add r18=r17,in0 173 cmp.eq p6,p0=DT_RELASZ,r16 // rela section size? 174 ;; 175(p6) mov r19=r17 176 cmp.eq p6,p0=DT_RELAENT,r16 // rela entry size? 177 ;; 178(p6) mov r20=r17 179 cmp.eq p6,p0=DT_JMPREL,r16 // PLT relocs? 180 ;; 181(p6) add r21=r17,in0 182 cmp.eq p6,p0=DT_PLTRELSZ,r16 // PLT relocs size? 183 ;; 184(p6) mov r22=r17 185 cmp.eq p6,p0=DT_SYMTAB,r16 // symbol table? 186 ;; 187(p6) add r29=r17,in0 188 ;; 189(p6) setf.sig f8=r29 190 cmp.eq p6,p0=DT_SYMENT,r16 // symbol entry size? 191 ;; 192(p6) setf.sig f9=r17 193 br.dptk 1b 194 1952: 196 cmp.lt p6,p0=0,r19 197(p6) br.cond.dptk 3f 198 ;; 199 mov r19=r22 200 mov r18=r21 201 mov r21=0 202 mov r22=0 203 ;; 204 cmp.lt p6,p0=0,r19 205(p6) br.cond.dptk 3f 206 ;; 207 mov r8=EFI_SUCCESS 208 br.dptk 9f 2093: 210 ld8 r29=[r18],8 // read r_offset 211 ;; 212 ld8 r16=[r18],8 // read r_info 213 add r15=r29,in0 // relocate r_offset 214 ;; 215 ld8 r17=[r18],8 // read r_addend 216 sub r19=r19,r20 // update relasz 217 extr.u r23=r16,0,32 // ELF64_R_TYPE(r16) 218 ;; 219 cmp.eq p6,p0=R_IA64_NONE,r23 220(p6) br.cond.dpnt.few 2b 221 ;; 222 cmp.eq p6,p0=R_IA64_REL32LSB,r23 223(p6) br.cond.dptk.few 3f 224 ;; 225 cmp.eq p6,p0=R_IA64_REL64LSB,r23 226(p6) br.cond.dptk.few 4f 227 ;; 228 extr.u r29=r16,32,32 // ELF64_R_SYM(r16) 229 ;; 230 setf.sig f10=r29 // so we can multiply 231 ;; 232 xma.lu f10=f10,f9,f8 // f10=symtab + r_sym*syment 233 ;; 234 getf.sig r29=f10 235 ;; 236 add r29=8,r29 // address of st_value 237 ;; 238 ld8 r29=[r29] // read symbol value 239 ;; 240 add r24=r29,in0 // relocate symbol value 241 ;; 242 cmp.eq p6,p0=R_IA64_DIR64LSB,r23 243(p6) br.cond.dptk.few 5f 244 ;; 245 cmp.eq p6,p0=R_IA64_FPTR64LSB,r23 246(p6) br.cond.dptk.few 6f 247 ;; 248 cmp.ne p6,p0=r28,r23 // IPLTLSB 249(p6) br.cond.dptk.few 2b 250 251 // IPLTLSB 252 add r29=r24,r17 // S + A 253 ;; 254 st8 [r15]=r29,8 // fdesc:FP 255 ;; 256 st8 [r15]=gp // fdesc:GP 257 br.cond.sptk.few 2b 258 259 // REL32LSB 2603: 261 add r29=in0,r17 262 ;; 263 st4 [r15]=r29 264 br.cond.sptk.few 2b 265 266 // REL64LSB 2674: 268 add r29=in0,r17 // BD + A 269 ;; 270 st8 [r15]=r29 // word64 271 br.cond.sptk.few 2b 272 273 // DIR64LSB 2745: 275 add r29=r24,r17 // S + A 276 ;; 277 st8 [r15]=r29 // word64 278 br.cond.sptk.few 2b 279 2806: 281 mov r29=r2 // FPTR64LSB 282 ;; 2837: 284 cmp.geu p6,p0=r29,r4 // end of fptrs? 285(p6) br.cond.dpnt.few 8f // can't find existing fptr 286 ld8 r17=[r29] // read function from fptr 287 ;; 288 cmp.eq p6,p0=r24,r17 // same function? 289 ;; 290(p6) st8 [r15]=r29 // reuse fptr 291(p6) br.cond.sptk.few 2b // done 292 add r29=16,r29 // next fptr 293 br.sptk.few 7b 2948: 295 mov r8=EFI_BUFFER_TOO_SMALL // failure return value 296 cmp.geu p6,p0=r4,r3 // space left? 297(p6) br.cond.dpnt.few 9f // bail out 298 st8 [r15]=r4 // install fptr 299 ;; 300 st8 [r4]=r24,8 // write fptr address 301 ;; 302 st8 [r4]=gp,8 // write fptr gp 303 br.cond.sptk.few 2b 304 3059: 306 mov ar.pfs=loc0 307 mov rp=loc1 308 ;; 309 br.ret.sptk.few rp 310END(_reloc) 311 312 .data 313 .align 16 314fptr_storage: 315 .space 1024*16 // XXX 316fptr_storage_end: 317