diff options
Diffstat (limited to 'arch/mips/fw/lib/call_o32.S')
| -rw-r--r-- | arch/mips/fw/lib/call_o32.S | 57 |
1 files changed, 35 insertions, 22 deletions
diff --git a/arch/mips/fw/lib/call_o32.S b/arch/mips/fw/lib/call_o32.S index b308b2a0613e..4703fe4dbd9a 100644 --- a/arch/mips/fw/lib/call_o32.S +++ b/arch/mips/fw/lib/call_o32.S @@ -1,7 +1,7 @@ /* * O32 interface for the 64 (or N32) ABI. * - * Copyright (C) 2002 Maciej W. Rozycki + * Copyright (C) 2002, 2014 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 @@ -12,28 +12,37 @@ #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. */ +/* 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) +/* 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 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. + * 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 @@ -51,32 +60,36 @@ NESTED(call_o32, O32_FRAMESZ, ra) 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) + + 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 a6,0x10(s0) - sw a7,0x14(s0) + sw a6,4*O32_SZREG(fp) + sw a7,5*O32_SZREG(fp) PTR_LA t0,O32_FRAMESZ(sp) - PTR_LA t1,0x18(s0) + 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 t1,4 + REG_ADDU t1,O32_SZREG bnez t2,1b - move sp,s0 + move sp,fp jalr jp - REG_L sp,O32_FRAMESZ_NEW-1*SZREG(sp) + REG_L sp,O32_NFRAMESZ-1*SZREG(sp) REG_L s0,O32_FRAMESZ-11*SZREG(sp) REG_L s1,O32_FRAMESZ-10*SZREG(sp) |