| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 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 | @ | 
|  | 27 | ENTRY(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 | 
|  | 33 | ENDPROC(do_vfp) | 
|  | 34 |  | 
|  | 35 | ENTRY(vfp_null_entry) | 
|  | 36 | dec_preempt_count_ti r10, r4 | 
|  | 37 | ret	lr | 
|  | 38 | ENDPROC(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 | 
|  | 48 | ENTRY(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 | 
|  | 53 | ENDPROC(vfp_testing_entry) | 
|  | 54 |  | 
|  | 55 | .align	2 | 
|  | 56 | VFP_arch_address: | 
|  | 57 | .word	VFP_arch | 
|  | 58 |  | 
|  | 59 | __FINIT |