1/* 2 * crt0_s.S: Entry function for SPU-side context save. 3 * 4 * Copyright (C) 2005 IBM 5 * 6 * Entry function for SPU-side of the context save sequence. 7 * Saves all 128 GPRs, sets up an initial stack frame, then 8 * branches to 'main'. 9 * 10 * 11 * This program is free software; you can redistribute it and/or modify 12 * it under the terms of the GNU General Public License as published by 13 * the Free Software Foundation; either version 2, or (at your option) 14 * any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 24 */ 25 26#include <asm/spu_csa.h> 27 28.data 29.align 7 30.globl regs_spill 31regs_spill: 32.space SIZEOF_SPU_SPILL_REGS, 0x0 33 34.text 35.global _start 36_start: 37 /* SPU Context Save Step 1: Save the first 16 GPRs. */ 38 stqa $0, regs_spill + 0 39 stqa $1, regs_spill + 16 40 stqa $2, regs_spill + 32 41 stqa $3, regs_spill + 48 42 stqa $4, regs_spill + 64 43 stqa $5, regs_spill + 80 44 stqa $6, regs_spill + 96 45 stqa $7, regs_spill + 112 46 stqa $8, regs_spill + 128 47 stqa $9, regs_spill + 144 48 stqa $10, regs_spill + 160 49 stqa $11, regs_spill + 176 50 stqa $12, regs_spill + 192 51 stqa $13, regs_spill + 208 52 stqa $14, regs_spill + 224 53 stqa $15, regs_spill + 240 54 55 /* SPU Context Save, Step 8: Save the remaining 112 GPRs. */ 56 ila $3, regs_spill + 256 57save_regs: 58 lqr $4, save_reg_insts 59save_reg_loop: 60 ai $4, $4, 4 61 .balignl 16, 0x40200000 62save_reg_insts: /* must be quad-word aligned. */ 63 stqd $16, 0($3) 64 stqd $17, 16($3) 65 stqd $18, 32($3) 66 stqd $19, 48($3) 67 andi $5, $4, 0x7F 68 stqr $4, save_reg_insts 69 ai $3, $3, 64 70 brnz $5, save_reg_loop 71 72 /* Initialize the stack pointer to point to 16368 73 * (16kb-16). The back chain pointer is initialized 74 * to NULL. 75 */ 76 il $0, 0 77 il $SP, 16368 78 stqd $0, 0($SP) 79 80 /* Allocate a minimum stack frame for the called main. 81 * This is needed so that main has a place to save the 82 * link register when it calls another function. 83 */ 84 stqd $SP, -160($SP) 85 ai $SP, $SP, -160 86 87 /* Call the program's main function. */ 88 brsl $0, main 89 90 /* In this case main should not return; if it does 91 * there has been an error in the sequence. Execute 92 * stop-and-signal with code=0. 93 */ 94.global exit 95.global _exit 96exit: 97_exit: 98 stop 0x0 99 100 /* Pad the size of this crt0.o to be multiple of 16 bytes. */ 101.balignl 16, 0x0 102 103