| Thomas Bogendoerfer | 231a35d | 2008-01-04 23:31:07 +0100 | [diff] [blame] | 1 | /* |
| Thomas Bogendoerfer | 231a35d | 2008-01-04 23:31:07 +0100 | [diff] [blame] | 2 | * O32 interface for the 64 (or N32) ABI. |
| 3 | * |
| 4 | * Copyright (C) 2002 Maciej W. Rozycki |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <asm/asm.h> |
| 13 | #include <asm/regdef.h> |
| 14 | |
| 15 | /* Maximum number of arguments supported. Must be even! */ |
| 16 | #define O32_ARGC 32 |
| Ralf Baechle | 7034228 | 2013-01-22 12:59:30 +0100 | [diff] [blame] | 17 | /* Number of static registers we save. */ |
| Thomas Bogendoerfer | 231a35d | 2008-01-04 23:31:07 +0100 | [diff] [blame] | 18 | #define O32_STATC 11 |
| 19 | /* Frame size for static register */ |
| 20 | #define O32_FRAMESZ (SZREG * O32_STATC) |
| 21 | /* Frame size on new stack */ |
| 22 | #define O32_FRAMESZ_NEW (SZREG + 4 * O32_ARGC) |
| 23 | |
| 24 | .text |
| 25 | |
| 26 | /* |
| 27 | * O32 function call dispatcher, for interfacing 32-bit ROM routines. |
| 28 | * |
| 29 | * The standard 64 (N32) calling sequence is supported, with a0 |
| 30 | * holding a function pointer, a1 a new stack pointer, a2-a7 -- its |
| 31 | * first six arguments and the stack -- remaining ones (up to O32_ARGC, |
| 32 | * including a2-a7). Static registers, gp and fp are preserved, v0 holds |
| 33 | * a result. This code relies on the called o32 function for sp and ra |
| 34 | * restoration and this dispatcher has to be placed in a KSEGx (or KUSEG) |
| 35 | * address space. Any pointers passed have to point to addresses within |
| 36 | * one of these spaces as well. |
| 37 | */ |
| 38 | NESTED(call_o32, O32_FRAMESZ, ra) |
| 39 | REG_SUBU sp,O32_FRAMESZ |
| 40 | |
| 41 | REG_S ra,O32_FRAMESZ-1*SZREG(sp) |
| 42 | REG_S fp,O32_FRAMESZ-2*SZREG(sp) |
| 43 | REG_S gp,O32_FRAMESZ-3*SZREG(sp) |
| 44 | REG_S s7,O32_FRAMESZ-4*SZREG(sp) |
| 45 | REG_S s6,O32_FRAMESZ-5*SZREG(sp) |
| 46 | REG_S s5,O32_FRAMESZ-6*SZREG(sp) |
| 47 | REG_S s4,O32_FRAMESZ-7*SZREG(sp) |
| 48 | REG_S s3,O32_FRAMESZ-8*SZREG(sp) |
| 49 | REG_S s2,O32_FRAMESZ-9*SZREG(sp) |
| 50 | REG_S s1,O32_FRAMESZ-10*SZREG(sp) |
| 51 | REG_S s0,O32_FRAMESZ-11*SZREG(sp) |
| 52 | |
| 53 | move jp,a0 |
| 54 | REG_SUBU s0,a1,O32_FRAMESZ_NEW |
| 55 | REG_S sp,O32_FRAMESZ_NEW-1*SZREG(s0) |
| 56 | |
| 57 | sll a0,a2,zero |
| 58 | sll a1,a3,zero |
| 59 | sll a2,a4,zero |
| 60 | sll a3,a5,zero |
| 61 | sw a6,0x10(s0) |
| 62 | sw a7,0x14(s0) |
| 63 | |
| 64 | PTR_LA t0,O32_FRAMESZ(sp) |
| 65 | PTR_LA t1,0x18(s0) |
| 66 | li t2,O32_ARGC-6 |
| 67 | 1: |
| 68 | lw t3,(t0) |
| 69 | REG_ADDU t0,SZREG |
| 70 | sw t3,(t1) |
| 71 | REG_SUBU t2,1 |
| 72 | REG_ADDU t1,4 |
| 73 | bnez t2,1b |
| 74 | |
| 75 | move sp,s0 |
| 76 | |
| 77 | jalr jp |
| 78 | |
| 79 | REG_L sp,O32_FRAMESZ_NEW-1*SZREG(sp) |
| 80 | |
| 81 | REG_L s0,O32_FRAMESZ-11*SZREG(sp) |
| 82 | REG_L s1,O32_FRAMESZ-10*SZREG(sp) |
| 83 | REG_L s2,O32_FRAMESZ-9*SZREG(sp) |
| 84 | REG_L s3,O32_FRAMESZ-8*SZREG(sp) |
| 85 | REG_L s4,O32_FRAMESZ-7*SZREG(sp) |
| 86 | REG_L s5,O32_FRAMESZ-6*SZREG(sp) |
| 87 | REG_L s6,O32_FRAMESZ-5*SZREG(sp) |
| 88 | REG_L s7,O32_FRAMESZ-4*SZREG(sp) |
| 89 | REG_L gp,O32_FRAMESZ-3*SZREG(sp) |
| 90 | REG_L fp,O32_FRAMESZ-2*SZREG(sp) |
| 91 | REG_L ra,O32_FRAMESZ-1*SZREG(sp) |
| 92 | |
| 93 | REG_ADDU sp,O32_FRAMESZ |
| 94 | jr ra |
| 95 | END(call_o32) |