| /* |
| * O32 interface for the 64 (or N32) ABI. |
| * |
| * Copyright (C) 2002 Maciej W. Rozycki |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| |
| #include <asm/asm.h> |
| #include <asm/regdef.h> |
| |
| /* Maximum number of arguments supported. Must be even! */ |
| #define O32_ARGC 32 |
| /* Number of static registers we save. */ |
| #define O32_STATC 11 |
| /* Frame size for static register */ |
| #define O32_FRAMESZ (SZREG * O32_STATC) |
| /* Frame size on new stack */ |
| #define O32_FRAMESZ_NEW (SZREG + 4 * O32_ARGC) |
| |
| .text |
| |
| /* |
| * O32 function call dispatcher, for interfacing 32-bit ROM routines. |
| * |
| * The standard 64 (N32) calling sequence is supported, with a0 |
| * holding a function pointer, a1 a new stack pointer, a2-a7 -- its |
| * first six arguments and the stack -- remaining ones (up to O32_ARGC, |
| * including a2-a7). Static registers, gp and fp are preserved, v0 holds |
| * a result. This code relies on the called o32 function for sp and ra |
| * restoration and this dispatcher has to be placed in a KSEGx (or KUSEG) |
| * address space. Any pointers passed have to point to addresses within |
| * one of these spaces as well. |
| */ |
| NESTED(call_o32, O32_FRAMESZ, ra) |
| REG_SUBU sp,O32_FRAMESZ |
| |
| REG_S ra,O32_FRAMESZ-1*SZREG(sp) |
| REG_S fp,O32_FRAMESZ-2*SZREG(sp) |
| REG_S gp,O32_FRAMESZ-3*SZREG(sp) |
| REG_S s7,O32_FRAMESZ-4*SZREG(sp) |
| REG_S s6,O32_FRAMESZ-5*SZREG(sp) |
| REG_S s5,O32_FRAMESZ-6*SZREG(sp) |
| REG_S s4,O32_FRAMESZ-7*SZREG(sp) |
| REG_S s3,O32_FRAMESZ-8*SZREG(sp) |
| REG_S s2,O32_FRAMESZ-9*SZREG(sp) |
| REG_S s1,O32_FRAMESZ-10*SZREG(sp) |
| REG_S s0,O32_FRAMESZ-11*SZREG(sp) |
| |
| move jp,a0 |
| REG_SUBU s0,a1,O32_FRAMESZ_NEW |
| REG_S sp,O32_FRAMESZ_NEW-1*SZREG(s0) |
| |
| sll a0,a2,zero |
| sll a1,a3,zero |
| sll a2,a4,zero |
| sll a3,a5,zero |
| sw a6,0x10(s0) |
| sw a7,0x14(s0) |
| |
| PTR_LA t0,O32_FRAMESZ(sp) |
| PTR_LA t1,0x18(s0) |
| li t2,O32_ARGC-6 |
| 1: |
| lw t3,(t0) |
| REG_ADDU t0,SZREG |
| sw t3,(t1) |
| REG_SUBU t2,1 |
| REG_ADDU t1,4 |
| bnez t2,1b |
| |
| move sp,s0 |
| |
| jalr jp |
| |
| REG_L sp,O32_FRAMESZ_NEW-1*SZREG(sp) |
| |
| REG_L s0,O32_FRAMESZ-11*SZREG(sp) |
| REG_L s1,O32_FRAMESZ-10*SZREG(sp) |
| REG_L s2,O32_FRAMESZ-9*SZREG(sp) |
| REG_L s3,O32_FRAMESZ-8*SZREG(sp) |
| REG_L s4,O32_FRAMESZ-7*SZREG(sp) |
| REG_L s5,O32_FRAMESZ-6*SZREG(sp) |
| REG_L s6,O32_FRAMESZ-5*SZREG(sp) |
| REG_L s7,O32_FRAMESZ-4*SZREG(sp) |
| REG_L gp,O32_FRAMESZ-3*SZREG(sp) |
| REG_L fp,O32_FRAMESZ-2*SZREG(sp) |
| REG_L ra,O32_FRAMESZ-1*SZREG(sp) |
| |
| REG_ADDU sp,O32_FRAMESZ |
| jr ra |
| END(call_o32) |
