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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 | /* SPDX-License-Identifier: GPL-2.0-or-later */ /* * O32 interface for the 64 (or N32) ABI. * * Copyright (C) 2002, 2014 Maciej W. Rozycki */ #include <asm/asm.h> #include <asm/regdef.h> /* O32 register size. */ #define O32_SZREG 4 /* Maximum number of arguments supported. Must be even! */ #define O32_ARGC 32 /* Number of static registers we save. */ #define O32_STATC 11 /* Argument area frame size. */ #define O32_ARGSZ (O32_SZREG * O32_ARGC) /* Static register save area frame size. */ #define O32_STATSZ (SZREG * O32_STATC) /* Stack pointer register save area frame size. */ #define O32_SPSZ SZREG /* Combined area frame size. */ #define O32_FRAMESZ (O32_ARGSZ + O32_SPSZ + O32_STATSZ) /* Switched stack frame size. */ #define O32_NFRAMESZ (O32_ARGSZ + O32_SPSZ) .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 pointer to the new stack to call the * function with or 0 if no stack switching is requested, a2-a7 -- the * function call's first six arguments, and the stack -- the remaining * arguments (up to O32_ARGC, including a2-a7). Static registers, gp * and fp are preserved, v0 holds the 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 move fp,sp beqz a1,0f REG_SUBU fp,a1,O32_NFRAMESZ 0: REG_S sp,O32_NFRAMESZ-1*SZREG(fp) sll a0,a2,zero sll a1,a3,zero sll a2,a4,zero sll a3,a5,zero sw a6,4*O32_SZREG(fp) sw a7,5*O32_SZREG(fp) PTR_LA t0,O32_FRAMESZ(sp) PTR_LA t1,6*O32_SZREG(fp) li t2,O32_ARGC-6 1: lw t3,(t0) REG_ADDU t0,SZREG sw t3,(t1) REG_SUBU t2,1 REG_ADDU t1,O32_SZREG bnez t2,1b move sp,fp jalr jp REG_L sp,O32_NFRAMESZ-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) |