1/* 2 * linux/arch/arm/vfp/entry.S 3 * 4 * Copyright (C) 2004 ARM Limited. 5 * Written by Deep Blue Solutions Limited. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11#include <linux/init.h> 12#include <linux/linkage.h> 13#include <asm/thread_info.h> 14#include <asm/vfpmacros.h> 15#include <asm/assembler.h> 16#include <asm/asm-offsets.h> 17 18@ VFP entry point. 19@ 20@ r0 = instruction opcode (32-bit ARM or two 16-bit Thumb) 21@ r2 = PC value to resume execution after successful emulation 22@ r9 = normal "successful" return address 23@ r10 = this threads thread_info structure 24@ lr = unrecognised instruction return address 25@ IRQs enabled. 26@ 27ENTRY(do_vfp) 28 inc_preempt_count r10, r4 29 ldr r4, .LCvfp 30 ldr r11, [r10, #TI_CPU] @ CPU number 31 add r10, r10, #TI_VFPSTATE @ r10 = workspace 32 ldr pc, [r4] @ call VFP entry point 33ENDPROC(do_vfp) 34 35ENTRY(vfp_null_entry) 36 dec_preempt_count_ti r10, r4 37 ret lr 38ENDPROC(vfp_null_entry) 39 40 .align 2 41.LCvfp: 42 .word vfp_vector 43 44@ This code is called if the VFP does not exist. It needs to flag the 45@ failure to the VFP initialisation code. 46 47 __INIT 48ENTRY(vfp_testing_entry) 49 dec_preempt_count_ti r10, r4 50 ldr r0, VFP_arch_address 51 str r0, [r0] @ set to non-zero value 52 ret r9 @ we have handled the fault 53ENDPROC(vfp_testing_entry) 54 55 .align 2 56VFP_arch_address: 57 .word VFP_arch 58 59 __FINIT 60