OpenCloudOS-Kernel/arch/arm/vfp/entry.S

72 lines
1.8 KiB
ArmAsm

/*
* linux/arch/arm/vfp/entry.S
*
* Copyright (C) 2004 ARM Limited.
* Written by Deep Blue Solutions Limited.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <asm/thread_info.h>
#include <asm/vfpmacros.h>
#include "../kernel/entry-header.S"
@ VFP entry point.
@
@ r0 = instruction opcode (32-bit ARM or two 16-bit Thumb)
@ r2 = PC value to resume execution after successful emulation
@ r9 = normal "successful" return address
@ r10 = this threads thread_info structure
@ lr = unrecognised instruction return address
@ IRQs disabled.
@
ENTRY(do_vfp)
#ifdef CONFIG_PREEMPT_COUNT
ldr r4, [r10, #TI_PREEMPT] @ get preempt count
add r11, r4, #1 @ increment it
str r11, [r10, #TI_PREEMPT]
#endif
enable_irq
ldr r4, .LCvfp
ldr r11, [r10, #TI_CPU] @ CPU number
add r10, r10, #TI_VFPSTATE @ r10 = workspace
ldr pc, [r4] @ call VFP entry point
ENDPROC(do_vfp)
ENTRY(vfp_null_entry)
#ifdef CONFIG_PREEMPT_COUNT
get_thread_info r10
ldr r4, [r10, #TI_PREEMPT] @ get preempt count
sub r11, r4, #1 @ decrement it
str r11, [r10, #TI_PREEMPT]
#endif
mov pc, lr
ENDPROC(vfp_null_entry)
.align 2
.LCvfp:
.word vfp_vector
@ This code is called if the VFP does not exist. It needs to flag the
@ failure to the VFP initialisation code.
__INIT
ENTRY(vfp_testing_entry)
#ifdef CONFIG_PREEMPT_COUNT
get_thread_info r10
ldr r4, [r10, #TI_PREEMPT] @ get preempt count
sub r11, r4, #1 @ decrement it
str r11, [r10, #TI_PREEMPT]
#endif
ldr r0, VFP_arch_address
str r5, [r0] @ known non-zero value
mov pc, r9 @ we have handled the fault
ENDPROC(vfp_testing_entry)
.align 2
VFP_arch_address:
.word VFP_arch
__FINIT