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 * Basic entry code, called from the kernel's undefined instruction trap. 12 * r0 = faulted instruction 13 * r5 = faulted PC+4 14 * r9 = successful return 15 * r10 = thread_info structure 16 * lr = failure return 17 */ 18#include <asm/thread_info.h> 19#include <asm/vfpmacros.h> 20#include "../kernel/entry-header.S" 21 22ENTRY(do_vfp) 23#ifdef CONFIG_PREEMPT 24 ldr r4, [r10, #TI_PREEMPT] @ get preempt count 25 add r11, r4, #1 @ increment it 26 str r11, [r10, #TI_PREEMPT] 27#endif 28 enable_irq 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#ifdef CONFIG_PREEMPT 37 get_thread_info r10 38 ldr r4, [r10, #TI_PREEMPT] @ get preempt count 39 sub r11, r4, #1 @ decrement it 40 str r11, [r10, #TI_PREEMPT] 41#endif 42 mov pc, lr 43ENDPROC(vfp_null_entry) 44 45 .align 2 46.LCvfp: 47 .word vfp_vector 48 49@ This code is called if the VFP does not exist. It needs to flag the 50@ failure to the VFP initialisation code. 51 52 __INIT 53ENTRY(vfp_testing_entry) 54#ifdef CONFIG_PREEMPT 55 get_thread_info r10 56 ldr r4, [r10, #TI_PREEMPT] @ get preempt count 57 sub r11, r4, #1 @ decrement it 58 str r11, [r10, #TI_PREEMPT] 59#endif 60 ldr r0, VFP_arch_address 61 str r5, [r0] @ known non-zero value 62 mov pc, r9 @ we have handled the fault 63ENDPROC(vfp_testing_entry) 64 65 .align 2 66VFP_arch_address: 67 .word VFP_arch 68 69 __FINIT 70