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Diffstat (limited to 'kernel/arch/sparc/execsp.S')
| -rw-r--r-- | kernel/arch/sparc/execsp.S | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/kernel/arch/sparc/execsp.S b/kernel/arch/sparc/execsp.S new file mode 100644 index 000000000000..4b225dd6d550 --- /dev/null +++ b/kernel/arch/sparc/execsp.S @@ -0,0 +1,123 @@ +/* $NetBSD: execsp.S,v 1.1 2025/04/20 22:33:41 riastradh Exp $ */ + +/*- + * Copyright (c) 2025 The NetBSD Foundation, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#define _LOCORE + +#include <machine/asm.h> + +RCSID("$NetBSD: execsp.S,v 1.1 2025/04/20 22:33:41 riastradh Exp $") + +#ifdef __PIC__ +#define SETHI(label, got, reg) \ + set label, reg; /* reg := &label - &GOT */ \ + ld [got + reg], reg /* reg := &label */ +#define LO(label, reg) \ + reg +#else +#define SETHI(label, got, reg) \ + sethi %hi(label), reg /* reg := &label - %lo(label) */ +#define LO(label, reg) \ + reg + %lo(label) +#endif + + .text + +/* + * void execsp_start(struct ps_strings *ps_strings@g1, + * void *obj_main@g2, void (*cleanup@g3)(void)) + * + * ELF entry point. Saves the stack pointer in startsp and defers + * to the usual csu __start routine. + */ +ENTRY(execsp_start) + PIC_PROLOGUE(%o1, %o2) /* o1 := GOT, clobber o2 */ + SETHI(_C_LABEL(startsp), %o1, %o2) /* o2 := &startup */ + call _C_LABEL(__start) /* jump to start via PLT */ + st %sp, [LO(_C_LABEL(startsp), %o2)] /* startsp := sp */ + /* don't care what happens here, caller must never return */ + ta 1 /* Tcc, trap always */ +END(execsp_start) + +/* + * void execsp_ctor(void) + * + * ELF constructor. Saves the stack pointer in ctorsp and + * returns. + */ +ENTRY(execsp_ctor) + /* Reminder: o6 is frame pointer, o7 + 8 is return address. */ + PIC_PROLOGUE(%g1, %o5) /* g1 := &GOT, clobber o5 */ + SETHI(_C_LABEL(ctorsp), %g1, %o5) /* o5 := &ctorsp */ + retl /* return to caller */ + st %sp, [LO(_C_LABEL(ctorsp), %o5)] /* ctorsp := sp */ +END(execsp_ctor) + + /* Make execsp_ctor a constructor. */ + .pushsection .ctors,"aw",@progbits + .p2align 2 + .long _C_LABEL(execsp_ctor) + .popsection + +/* + * int main(int argc@a0, char **argv@a1, ...) + * + * Main function. Saves the stack pointer in mainsp and returns + * zero. We will call execsp_main in execsp_dtor once dtorsp has + * been initialized. + */ +ENTRY(main) + /* Reminder: o6 is frame pointer, o7 + 8 is return address. */ + PIC_PROLOGUE(%g1, %o5) /* g1 := &GOT, clobber o5 */ + SETHI(_C_LABEL(mainsp), %g1, %o5) /* o5 := &mainsp */ + st %sp, [LO(_C_LABEL(mainsp), %o5)] /* mainsp := sp */ + retl /* return to caller */ + mov 0, %o0 /* return 0 */ +END(main) + +/* + * void execsp_dtor(void) + * + * ELF destructor. Saves the stack pointer in dtorsp and defers + * to the C execsp_main in h_execsp.c to report the stack pointers + * back to the t_signal_and_sp parent. + */ +ENTRY(execsp_dtor) + /* Reminder: o6 is frame pointer, o7 + 8 is return address. */ + PIC_PROLOGUE(%g1, %o5) /* g1 := &GOT, clobber o5 */ + SETHI(_C_LABEL(dtorsp), %g1, %o5) /* o5 := &dtorsp - &GOT */ + st %sp, [LO(_C_LABEL(dtorsp), %o5)] /* dtorsp := sp */ + mov %o7, %o5 /* save return address */ + call _C_LABEL(execsp_main) /* tail call to execsp_main */ + mov %o5, %o7 /* restore return address */ +END(execsp_dtor) + + /* Make execsp_ctor a destructor. */ + .pushsection .dtors,"aw",@progbits + .p2align 2 + .long _C_LABEL(execsp_dtor) + .popsection |