1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * crt0_s.S: Entry function for SPU-side context save. 4 * 5 * Copyright (C) 2005 IBM 6 * 7 * Entry function for SPU-side of the context save sequence. 8 * Saves all 128 GPRs, sets up an initial stack frame, then 9 * branches to 'main'. 10 */ 11 12 #include <asm/spu_csa.h> 13 14 .data 15 .align 7 16 .globl regs_spill 17 regs_spill: 18 .space SIZEOF_SPU_SPILL_REGS, 0x0 19 20 .text 21 .global _start 22 _start: 23 /* SPU Context Save Step 1: Save the first 16 GPRs. */ 24 stqa $0, regs_spill + 0 25 stqa $1, regs_spill + 16 26 stqa $2, regs_spill + 32 27 stqa $3, regs_spill + 48 28 stqa $4, regs_spill + 64 29 stqa $5, regs_spill + 80 30 stqa $6, regs_spill + 96 31 stqa $7, regs_spill + 112 32 stqa $8, regs_spill + 128 33 stqa $9, regs_spill + 144 34 stqa $10, regs_spill + 160 35 stqa $11, regs_spill + 176 36 stqa $12, regs_spill + 192 37 stqa $13, regs_spill + 208 38 stqa $14, regs_spill + 224 39 stqa $15, regs_spill + 240 40 41 /* SPU Context Save, Step 8: Save the remaining 112 GPRs. */ 42 ila $3, regs_spill + 256 43 save_regs: 44 lqr $4, save_reg_insts 45 save_reg_loop: 46 ai $4, $4, 4 47 .balignl 16, 0x40200000 48 save_reg_insts: /* must be quad-word aligned. */ 49 stqd $16, 0($3) 50 stqd $17, 16($3) 51 stqd $18, 32($3) 52 stqd $19, 48($3) 53 andi $5, $4, 0x7F 54 stqr $4, save_reg_insts 55 ai $3, $3, 64 56 brnz $5, save_reg_loop 57 58 /* Initialize the stack pointer to point to 16368 59 * (16kb-16). The back chain pointer is initialized 60 * to NULL. 61 */ 62 il $0, 0 63 il $SP, 16368 64 stqd $0, 0($SP) 65 66 /* Allocate a minimum stack frame for the called main. 67 * This is needed so that main has a place to save the 68 * link register when it calls another function. 69 */ 70 stqd $SP, -160($SP) 71 ai $SP, $SP, -160 72 73 /* Call the program's main function. */ 74 brsl $0, main 75 76 /* In this case main should not return; if it does 77 * there has been an error in the sequence. Execute 78 * stop-and-signal with code=0. 79 */ 80 .global exit 81 .global _exit 82 exit: 83 _exit: 84 stop 0x0 85 86 /* Pad the size of this crt0.o to be multiple of 16 bytes. */ 87 .balignl 16, 0x0 88 89