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Diffstat (limited to 'arch/mips/fw/lib/call_o32.S')
-rw-r--r-- | arch/mips/fw/lib/call_o32.S | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/arch/mips/fw/lib/call_o32.S b/arch/mips/fw/lib/call_o32.S new file mode 100644 index 00000000000..bdf7d1d4081 --- /dev/null +++ b/arch/mips/fw/lib/call_o32.S @@ -0,0 +1,97 @@ +/* + * arch/mips/dec/prom/call_o32.S + * + * 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) |