xref: /openbmc/linux/arch/m68k/fpsp040/x_unimp.S (revision d9fd5a71)
1|
2|	x_unimp.sa 3.3 7/1/91
3|
4|	fpsp_unimp --- FPSP handler for unimplemented instruction
5|	exception.
6|
7| Invoked when the user program encounters a floating-point
8| op-code that hardware does not support.  Trap vector# 11
9| (See table 8-1 MC68030 User's Manual).
10|
11|
12| Note: An fsave for an unimplemented inst. will create a short
13| fsave stack.
14|
15|  Input: 1. Six word stack frame for unimplemented inst, four word
16|            for illegal
17|            (See table 8-7 MC68030 User's Manual).
18|         2. Unimp (short) fsave state frame created here by fsave
19|            instruction.
20|
21|
22|		Copyright (C) Motorola, Inc. 1990
23|			All Rights Reserved
24|
25|       For details on the license for this file, please see the
26|       file, README, in this same directory.
27
28X_UNIMP:	|idnt    2,1 | Motorola 040 Floating Point Software Package
29
30	|section	8
31
32#include "fpsp.h"
33
34	|xref	get_op
35	|xref	do_func
36	|xref	sto_res
37	|xref	gen_except
38	|xref	fpsp_fmt_error
39
40	.global	fpsp_unimp
41	.global	uni_2
42fpsp_unimp:
43	link		%a6,#-LOCAL_SIZE
44	fsave		-(%a7)
45uni_2:
46	moveml		%d0-%d1/%a0-%a1,USER_DA(%a6)
47	fmovemx	%fp0-%fp3,USER_FP0(%a6)
48	fmoveml	%fpcr/%fpsr/%fpiar,USER_FPCR(%a6)
49	moveb		(%a7),%d0		|test for valid version num
50	andib		#0xf0,%d0		|test for $4x
51	cmpib		#VER_4,%d0	|must be $4x or exit
52	bnel		fpsp_fmt_error
53|
54|	Temporary D25B Fix
55|	The following lines are used to ensure that the FPSR
56|	exception byte and condition codes are clear before proceeding
57|
58	movel		USER_FPSR(%a6),%d0
59	andl		#0xFF00FF,%d0	|clear all but accrued exceptions
60	movel		%d0,USER_FPSR(%a6)
61	fmovel		#0,%FPSR |clear all user bits
62	fmovel		#0,%FPCR	|clear all user exceptions for FPSP
63
64	clrb		UFLG_TMP(%a6)	|clr flag for unsupp data
65
66	bsrl		get_op		|go get operand(s)
67	clrb		STORE_FLG(%a6)
68	bsrl		do_func		|do the function
69	fsave		-(%a7)		|capture possible exc state
70	tstb		STORE_FLG(%a6)
71	bnes		no_store	|if STORE_FLG is set, no store
72	bsrl		sto_res		|store the result in user space
73no_store:
74	bral		gen_except	|post any exceptions and return
75
76	|end
77