arm/nwfpe/entry.S

1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3     NetWinder Floating Point Emulator
14 /* This is the kernel's entry point into the floating point emulator.
24 	strb	r8, [r10, #TSK_USED_MATH]	@ set current->used_math
27 	ldr	pc, [r4]			@ Call FP emulator entry point
40 is used as a flag to detect the first time a process uses floating point,
49 2) It calls EmulateAll to emulate a floating point instruction.
52 3) If an instruction has been emulated successfully, it looks ahead at
53 the next instruction.  If it is a floating point instruction, it
55 way it repeatedly looks ahead and executes floating point instructions
56 until it encounters a non floating point instruction, at which time it
60 floating point instructions.  GCC attempts to group floating point
62 several floating point instructions.  */
64 #include <asm/asm-offsets.h>
68 	mov	r4, lr			@ save the failure-return addresses
113 	.align	3
118 	@ Check whether the instruction is a co-processor instruction.
119 	@ If yes, we need to call the relevant co-processor handler.
131 	sub	r4, r4, #4			@ ARM instruction at user PC - 4
155 	ret	lr				@ CP#3
171 	ldr_va	pc, fp_enter, tmp=r4		@ Call FP module USR entry point