/*      $NetBSD: pmon32.S,v 1.2 2015/06/26 22:32:23 matt Exp $ */
/*      OpenBSD: pmon32.S,v 1.4 2010/02/18 18:53:33 miod Exp    */

/*
 * Copyright (c) 2009 Miodrag Vallat.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * Wrapper routines to invoke PMON2000 functions from 64-bit code.
 *
 * PMON is compiled as 64 bit code, using the gcc o64 ABI (similar to the o32
 * ABI, but using 64 bit registers).
 *
 * As a result, only up to four arguments to functions will be passed through
 * registers.  It's up to the caller to never invoke pmon_printf() with more
 * than four arguments; other functions are not affected.
 */

#include <machine/asm.h>

#ifdef _STANDALONE
#include <machine/param.h>
#else
#include "assym.h"
#endif

        .set    mips3

        .data
        .globl  pmon_callvec
pmon_callvec:
        .word   0

        .text
#define PMON_CALLFRAME_SIZ (CALLFRAME_SIZ)
/*
 * Note that we need to provide a PMON_CALLFRAME_SIZ untouched area above sp,
 * or we'll risk our stack being corrupted upon return.
 */

#define FRAMESZ(sz)     (((sz) + ALSK) & ~ALSK)

#define PMON_WRAP(name, index) \
        NNON_LEAF(name, FRAMESZ(PMON_CALLFRAME_SIZ + 11 * SZREG),  ra); \
        PTR_SUBU sp, sp, FRAMESZ(PMON_CALLFRAME_SIZ + 11 * SZREG); \
        REG_S   ra, (10 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        .mask   0xc0ff0000, (CALLFRAME_RA - FRAMESZ(PMON_CALLFRAME_SIZ + 10 * SZREG)); \
        REG_S   s0, (0 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   s1, (1 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   s2, (2 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   s3, (3 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   s4, (4 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   s5, (5 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   s6, (6 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   s7, (7 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   s8, (8 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_S   t8, (9 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        lw      t0, pmon_callvec; \
        lw      t0, (index) * 4 (t0); \
        jalr    t0; \
        nop; \
        REG_L   t8, (9 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s8, (8 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s7, (7 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s6, (6 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s5, (5 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s4, (4 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s3, (3 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s2, (2 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s1, (1 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   s0, (0 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        REG_L   ra, (10 * SZREG + PMON_CALLFRAME_SIZ)(sp); \
        PTR_ADDU sp, sp, FRAMESZ(PMON_CALLFRAME_SIZ + 11 * SZREG); \
        jr      ra; \
        nop; \
        END(name)

PMON_WRAP(pmon_printf, 5)
PMON_WRAP(pmon_gets, 7)
#ifdef _STANDALONE
PMON_WRAP(pmon_open, 0)
PMON_WRAP(pmon_close, 1)
PMON_WRAP(pmon_read, 2)
PMON_WRAP(pmon_lseek, 4)
PMON_WRAP(pmon_cacheflush, 6)
#endif
#if 0   /* unused */
PMON_WRAP(pmon_write, 3)
#endif