start.S revision 77943
1/*- 2 * Copyright (c) 2001 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/boot/ia64/efi/start.S 77943 2001-06-09 16:49:51Z dfr $ 27 */ 28 29 .text 30 31#include <sys/cdefs.h> 32#include <machine/asm.h> 33 34#define EFI_SUCCESS 0 35#define EFI_LOAD_ERROR 1 36#define EFI_BUFFER_TOO_SMALL 5 37 38#define DT_NULL 0 /* Terminating entry. */ 39#define DT_NEEDED 1 /* String table offset of a needed shared 40 library. */ 41#define DT_PLTRELSZ 2 /* Total size in bytes of PLT relocations. */ 42#define DT_PLTGOT 3 /* Processor-dependent address. */ 43#define DT_HASH 4 /* Address of symbol hash table. */ 44#define DT_STRTAB 5 /* Address of string table. */ 45#define DT_SYMTAB 6 /* Address of symbol table. */ 46#define DT_RELA 7 /* Address of ElfNN_Rela relocations. */ 47#define DT_RELASZ 8 /* Total size of ElfNN_Rela relocations. */ 48#define DT_RELAENT 9 /* Size of each ElfNN_Rela relocation entry. */ 49#define DT_STRSZ 10 /* Size of string table. */ 50#define DT_SYMENT 11 /* Size of each symbol table entry. */ 51#define DT_INIT 12 /* Address of initialization function. */ 52#define DT_FINI 13 /* Address of finalization function. */ 53#define DT_SONAME 14 /* String table offset of shared object 54 name. */ 55#define DT_RPATH 15 /* String table offset of library path. */ 56#define DT_SYMBOLIC 16 /* Indicates "symbolic" linking. */ 57#define DT_REL 17 /* Address of ElfNN_Rel relocations. */ 58#define DT_RELSZ 18 /* Total size of ElfNN_Rel relocations. */ 59#define DT_RELENT 19 /* Size of each ElfNN_Rel relocation. */ 60#define DT_PLTREL 20 /* Type of relocation used for PLT. */ 61#define DT_DEBUG 21 /* Reserved (not used). */ 62#define DT_TEXTREL 22 /* Indicates there may be relocations in 63 non-writable segments. */ 64#define DT_JMPREL 23 /* Address of PLT relocations. */ 65 66#define DT_COUNT 24 /* Number of defined d_tag values. */ 67 68#define R_IA64_NONE 0 /* None */ 69#define R_IA64_DIR64MSB 0x26 /* word64 MSB S + A */ 70#define R_IA64_DIR64LSB 0x27 /* word64 LSB S + A */ 71#define R_IA64_FPTR64MSB 0x46 /* word64 MSB @fptr(S + A) */ 72#define R_IA64_FPTR64LSB 0x47 /* word64 LSB @fptr(S + A) */ 73#define R_IA64_REL64MSB 0x6e /* word64 MSB BD + A */ 74#define R_IA64_REL64LSB 0x6f /* word64 LSB BD + A */ 75 76ENTRY(_start, 2) 77 alloc loc0=ar.pfs,2,3,3,0 78 mov loc1=rp 79 movl loc2=@gprel(ImageBase) 80 ;; 81 br.sptk.few 9f 82 add loc2=gp,loc2 83 ;; 84 mov out0=loc2 85 mov out1=in1 86 ;; 87 br.call.sptk.few rp=_reloc // relocate image 88 89 cmp.ne p6,p0=EFI_SUCCESS,r8 // did it work? 90(p6) br.cond.dpnt.few 9f 91 92 mov out0=in0 // image_handle 93 mov out1=in1 // system_table 94 br.call.sptk.few rp=efi_main 959: 96 mov ar.pfs=loc0 97 mov rp=loc1 98 ;; 99 br.ret.sptk.few rp 100END(_start) 101 102 // PLABEL for PE32+ 103 .global _start_plabel 104 .section .plabel, "a" 105 .align 16 106_start_plabel: 107 .quad _start 108 .quad __gp 109 .previous 110 111 // A PE32+ relocation entry for the plabel 112 113 .section .reloc, "a" 114 .long _start_plabel 115 .long 12 116 .short (10 << 12) + 0 117 .short (10 << 12) + 8 118 .previous 119 120 // in0: image base 121 // in1: system table 122STATIC_ENTRY(_reloc, 2) 123 alloc loc0=ar.pfs,2,2,2,0 124 mov loc1=rp 125 ;; 126 movl r15=@gprel(_DYNAMIC) // find _DYNAMIC etc. 127 movl r2=@gprel(fptr_storage) 128 movl r3=@gprel(fptr_storage_end) 129 ;; 130 add r15=r15,gp // relocate _DYNAMIC etc. 131 add r2=r2,gp 132 add r3=r3,gp 133 ;; 1341: ld8 r16=[r15],8 // read r15->d_tag 135 ;; 136 ld8 r17=[r15],8 // and r15->d_val 137 ;; 138 cmp.eq p6,p0=DT_NULL,r16 // done? 139(p6) br.cond.dpnt.few 2f 140 ;; 141 cmp.eq p6,p0=DT_RELA,r16 142 ;; 143(p6) add r18=r17,in0 // found rela section 144 ;; 145 cmp.eq p6,p0=DT_RELASZ,r16 146 ;; 147(p6) mov r19=r17 // found rela size 148 ;; 149 cmp.eq p6,p0=DT_SYMTAB,r16 150 ;; 151(p6) add r20=r17,in0 // found symbol table 152 ;; 153(p6) setf.sig f8=r20 154 ;; 155 cmp.eq p6,p0=DT_SYMENT,r16 156 ;; 157(p6) setf.sig f9=r17 // found symbol entry size 158 ;; 159 cmp.eq p6,p0=DT_RELAENT,r16 160 ;; 161(p6) mov r22=r17 // found rela entry size 162 ;; 163 br.sptk.few 1b 164 1652: 166 ld8 r15=[r18],8 // read r_offset 167 ;; 168 ld8 r16=[r18],8 // read r_info 169 add r15=r15,in0 // relocate r_offset 170 ;; 171 ld8 r17=[r18],8 // read r_addend 172 sub r19=r19,r22 // update relasz 173 174 extr.u r23=r16,0,32 // ELF64_R_TYPE(r16) 175 ;; 176 cmp.eq p6,p0=R_IA64_NONE,r23 177(p6) br.cond.dpnt.few 3f 178 ;; 179 cmp.eq p6,p0=R_IA64_DIR64LSB,r23 180 ;; 181(p6) br.cond.dptk.few 4f 182 ;; 183 cmp.eq p6,p0=R_IA64_FPTR64LSB,r23 184 ;; 185(p6) br.cond.dptk.few 5f 186 ;; 187 cmp.eq p6,p0=R_IA64_REL64LSB,r23 188 ;; 189(p6) br.cond.dptk.few 4f 190 ;; 191 1923: cmp.ltu p6,p0=0,r19 // more? 193(p6) br.cond.dptk.few 2b // loop 194 195 mov r8=EFI_SUCCESS // success return value 196 ;; 197 br.cond.sptk.few 9f // done 198 1994: 200 ld8 r16=[r15] // read value 201 ;; 202 add r16=r16,in0 // relocate it 203 ;; 204 st8 [r15]=r16 // and store it back 205 br.cond.sptk.few 3b 206 2075: 208 extr.u r23=r16,32,32 // ELF64_R_SYM(r16) 209 ;; 210 setf.sig f10=r23 // so we can multiply 211 ;; 212 xma.lu f10=f10,f9,f8 // f10=symtab + r_sym*syment 213 ;; 214 getf.sig r16=f10 215 mov r8=EFI_BUFFER_TOO_SMALL // failure return value 216 ;; 217 cmp.geu p6,p0=r2,r3 // space left? 218(p6) br.cond.dpnt.few 9f // bail out 219 220 st8 [r15]=r2 // install fptr 221 add r16=8,r16 // address of st_value 222 ;; 223 ld8 r16=[r16] // read symbol value 224 ;; 225 add r16=r16,in0 // relocate symbol value 226 ;; 227 st8 [r2]=r16,8 // write fptr address 228 ;; 229 st8 [r2]=gp,8 // write fptr gp 230 br.cond.sptk.few 3b 231 2329: 233 mov ar.pfs=loc0 234 mov rp=loc1 235 ;; 236 br.ret.sptk.few rp 237 238END(_reloc) 239 240 // in0: system table 241 // in1: character 242ENTRY(_putchar, 2) 243 alloc loc0=ar.pfs,2,3,2,0 244 mov loc1=rp 245 mov loc2=gp 246 add sp=-32,sp 247 ;; 248 add r14=64,in0 // r14 = &in1->ConOut 249 ;; 250 ld8 r14=[r14] // r14 = in1->ConOut 251 ;; 252 add r15=8,r14 // r15 = &r14->OutputString 253 mov out0=r14 254 mov out1=sp 255 mov r16=sp 256 ;; 257 ld8 r15=[r15] // r15 = r14->OutputString 258 st2 [r16]=in1,2 // write character 259 ;; 260 st2 [r16]=r0 // terminate 261 ld8 r17=[r15],8 // function address 262 ;; 263 ld8 gp=[r15] // function gp 264 mov b6=r17 // transfer to branch register 265 ;; 266 br.call.sptk.few rp=b6 // call function 267 ;; 268 mov gp=loc2 // restore gp 269 mov ar.pfs=loc0 270 mov rp=loc1 271 add sp=32,sp 272 ;; 273 br.ret.sptk.few rp 274 275END(_putchar) 276 277 // in0: system table 278 // in1: string 279ENTRY(_puts, 2) 280 alloc loc0=ar.pfs,3,2,2,0 281 mov loc1=rp 282 ;; 283 mov out0=in0 284 ;; 2851: ld1 out1=[in1],1 286 ;; 287 cmp.eq p6,p0=r0,out1 288(p6) br.cond.dpnt.few 9f 289 ;; 290 br.call.sptk.few rp=_putchar 291 ;; 292 br.cond.sptk.few 1b 2939: 294 mov ar.pfs=loc0 295 mov rp=loc1 296 ;; 297 br.ret.sptk.few rp 298END(_puts) 299 300 // in0: system table 301 // in1: number 302ENTRY(_puthex, 2) 303 alloc loc0=ar.pfs,2,3,2,0 304 mov loc1=rp 305 mov loc2=ar.lc 306 ;; 307 mov out0=in0 308 mov ar.lc=15 309 ;; 3101: extr.u out1=in1,60,4 311 ;; 312 cmp.leu p6,p7=10,out1 313 ;; 314(p6) add out1='a'-10,out1 315(p7) add out1='0',out1 316 dep.z in1=in1,4,60 317 ;; 318 br.call.sptk.few rp=_putchar 319 ;; 320 br.cloop.sptk.few 1b 321 ;; 322 mov out1='\r' 323 ;; 324 br.call.sptk.few rp=_putchar 325 ;; 326 mov out1='\n' 327 ;; 328 br.call.sptk.few rp=_putchar 329 ;; 3309: 331 mov ar.pfs=loc0 332 mov rp=loc1 333 mov ar.lc=loc2 334 ;; 335 br.ret.sptk.few rp 336END(_puthex) 337 338 .data 339 .align 16 340 341fptr_storage: 342 .space 1024*16 // XXX 343fptr_storage_end: 344