/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Split from ftrace_64.S
 */

#include <linux/export.h>
#include <linux/magic.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/ftrace.h>
#include <asm/ppc-opcode.h>

_GLOBAL_TOC(ftrace_caller)
        lbz     r3, PACA_FTRACE_ENABLED(r13)
        cmpdi   r3, 0
        beqlr

        /* Taken from output of objdump from lib64/glibc */
        mflr    r3
        ld      r11, 0(r1)
        stdu    r1, -112(r1)
        std     r3, 128(r1)
        ld      r4, 16(r11)
        subi    r3, r3, MCOUNT_INSN_SIZE
.globl ftrace_call
ftrace_call:
        bl      ftrace_stub
        nop
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
.globl ftrace_graph_call
ftrace_graph_call:
        b       ftrace_graph_stub
_GLOBAL(ftrace_graph_stub)
#endif
        ld      r0, 128(r1)
        mtlr    r0
        addi    r1, r1, 112

_GLOBAL(ftrace_stub)
        blr

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(ftrace_graph_caller)
        addi    r5, r1, 112
        /* load r4 with local address */
        ld      r4, 128(r1)
        subi    r4, r4, MCOUNT_INSN_SIZE

        /* Grab the LR out of the caller stack frame */
        ld      r11, 112(r1)
        ld      r3, 16(r11)

        bl      prepare_ftrace_return
        nop

        /*
         * prepare_ftrace_return gives us the address we divert to.
         * Change the LR in the callers stack frame to this.
         */
        ld      r11, 112(r1)
        std     r3, 16(r11)

        ld      r0, 128(r1)
        mtlr    r0
        addi    r1, r1, 112
        blr
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */

.pushsection ".tramp.ftrace.text","aw",@progbits;
.globl ftrace_tramp_text
ftrace_tramp_text:
        .space 32
.popsection

.pushsection ".tramp.ftrace.init","aw",@progbits;
.globl ftrace_tramp_init
ftrace_tramp_init:
        .space 32
.popsection

_GLOBAL(mcount)
_GLOBAL(_mcount)
EXPORT_SYMBOL(_mcount)
        mflr    r12
        mtctr   r12
        mtlr    r0
        bctr

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(return_to_handler)
        /* need to save return values */
#ifdef CONFIG_PPC64
        std     r4,  -32(r1)
        std     r3,  -24(r1)
        /* save TOC */
        std     r2,  -16(r1)
        std     r31, -8(r1)
        mr      r31, r1
        stdu    r1, -112(r1)

        /*
         * We might be called from a module.
         * Switch to our TOC to run inside the core kernel.
         */
        LOAD_PACA_TOC()
#else
        stwu    r1, -16(r1)
        stw     r3, 8(r1)
        stw     r4, 12(r1)
#endif

        bl      ftrace_return_to_handler
        nop

        /* return value has real return address */
        mtlr    r3

#ifdef CONFIG_PPC64
        ld      r1, 0(r1)
        ld      r4,  -32(r1)
        ld      r3,  -24(r1)
        ld      r2,  -16(r1)
        ld      r31, -8(r1)
#else
        lwz     r3, 8(r1)
        lwz     r4, 12(r1)
        addi    r1, r1, 16
#endif

        /* Jump back to real return address */
        blr
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */