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| /* SPDX-License-Identifier: GPL-2.0-or-later */
| /*
| * crt0_r.S: Entry function for SPU-side context restore.
| *
| * Copyright (C) 2005 IBM
| *
| * Entry and exit function for SPU-side of the context restore
| * sequence. Sets up an initial stack frame, then branches to
| * 'main'. On return, restores all 128 registers from the LSCSA
| * and exits.
| */
|
| #include <asm/spu_csa.h>
|
| .data
| .align 7
| .globl regs_spill
| regs_spill:
| .space SIZEOF_SPU_SPILL_REGS, 0x0
|
| .text
| .global _start
| _start:
| /* Initialize the stack pointer to point to 16368
| * (16kb-16). The back chain pointer is initialized
| * to NULL.
| */
| il $0, 0
| il $SP, 16368
| stqd $0, 0($SP)
|
| /* Allocate a minimum stack frame for the called main.
| * This is needed so that main has a place to save the
| * link register when it calls another function.
| */
| stqd $SP, -160($SP)
| ai $SP, $SP, -160
|
| /* Call the program's main function. */
| brsl $0, main
|
| .global exit
| .global _exit
| exit:
| _exit:
| /* SPU Context Restore, Step 5: Restore the remaining 112 GPRs. */
| ila $3, regs_spill + 256
| restore_regs:
| lqr $4, restore_reg_insts
| restore_reg_loop:
| ai $4, $4, 4
| .balignl 16, 0x40200000
| restore_reg_insts: /* must be quad-word aligned. */
| lqd $16, 0($3)
| lqd $17, 16($3)
| lqd $18, 32($3)
| lqd $19, 48($3)
| andi $5, $4, 0x7F
| stqr $4, restore_reg_insts
| ai $3, $3, 64
| brnz $5, restore_reg_loop
|
| /* SPU Context Restore Step 17: Restore the first 16 GPRs. */
| lqa $0, regs_spill + 0
| lqa $1, regs_spill + 16
| lqa $2, regs_spill + 32
| lqa $3, regs_spill + 48
| lqa $4, regs_spill + 64
| lqa $5, regs_spill + 80
| lqa $6, regs_spill + 96
| lqa $7, regs_spill + 112
| lqa $8, regs_spill + 128
| lqa $9, regs_spill + 144
| lqa $10, regs_spill + 160
| lqa $11, regs_spill + 176
| lqa $12, regs_spill + 192
| lqa $13, regs_spill + 208
| lqa $14, regs_spill + 224
| lqa $15, regs_spill + 240
|
| /* Under normal circumstances, the 'exit' function
| * terminates with 'stop SPU_RESTORE_COMPLETE',
| * indicating that the SPU-side restore code has
| * completed.
| *
| * However it is possible that instructions immediately
| * following the 'stop 0x3ffc' have been modified at run
| * time so as to recreate the exact SPU_Status settings
| * from the application, e.g. illegal instruciton, halt,
| * etc.
| */
| .global exit_fini
| .global _exit_fini
| exit_fini:
| _exit_fini:
| stop SPU_RESTORE_COMPLETE
| stop 0
| stop 0
| stop 0
|
| /* Pad the size of this crt0.o to be multiple of 16 bytes. */
| .balignl 16, 0x0
|
|
