xref: /openbmc/linux/arch/sparc/lib/VISsave.S (revision f2a55d08)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * VISsave.S: Code for saving FPU register state for
4 *            VIS routines. One should not call this directly,
5 *            but use macros provided in <asm/visasm.h>.
6 *
7 * Copyright (C) 1998 Jakub Jelinek (jj@ultra.linux.cz)
8 */
9
10#include <linux/export.h>
11#include <linux/linkage.h>
12
13#include <asm/asi.h>
14#include <asm/page.h>
15#include <asm/ptrace.h>
16#include <asm/visasm.h>
17#include <asm/thread_info.h>
18
19	/* On entry: %o5=current FPRS value, %g7 is callers address */
20	/* May clobber %o5, %g1, %g2, %g3, %g7, %icc, %xcc */
21
22	/* Nothing special need be done here to handle pre-emption, this
23	 * FPU save/restore mechanism is already preemption safe.
24	 */
25	.text
26	.align		32
27ENTRY(VISenter)
28	ldub		[%g6 + TI_FPDEPTH], %g1
29	brnz,a,pn	%g1, 1f
30	 cmp		%g1, 1
31	stb		%g0, [%g6 + TI_FPSAVED]
32	stx		%fsr, [%g6 + TI_XFSR]
339:	jmpl		%g7 + %g0, %g0
34	 nop
351:	bne,pn		%icc, 2f
36
37	 srl		%g1, 1, %g1
38vis1:	ldub		[%g6 + TI_FPSAVED], %g3
39	stx		%fsr, [%g6 + TI_XFSR]
40	or		%g3, %o5, %g3
41	stb		%g3, [%g6 + TI_FPSAVED]
42	rd		%gsr, %g3
43	clr		%g1
44	ba,pt		%xcc, 3f
45
46	 stx		%g3, [%g6 + TI_GSR]
472:	add		%g6, %g1, %g3
48	mov		FPRS_DU | FPRS_DL | FPRS_FEF, %o5
49	sll		%g1, 3, %g1
50	stb		%o5, [%g3 + TI_FPSAVED]
51	rd		%gsr, %g2
52	add		%g6, %g1, %g3
53	stx		%g2, [%g3 + TI_GSR]
54
55	add		%g6, %g1, %g2
56	stx		%fsr, [%g2 + TI_XFSR]
57	sll		%g1, 5, %g1
583:	andcc		%o5, FPRS_DL|FPRS_DU, %g0
59	be,pn		%icc, 9b
60	 add		%g6, TI_FPREGS, %g2
61	andcc		%o5, FPRS_DL, %g0
62
63	be,pn		%icc, 4f
64	 add		%g6, TI_FPREGS+0x40, %g3
65	membar		#Sync
66	stda		%f0, [%g2 + %g1] ASI_BLK_P
67	stda		%f16, [%g3 + %g1] ASI_BLK_P
68	membar		#Sync
69	andcc		%o5, FPRS_DU, %g0
70	be,pn		%icc, 5f
714:	 add		%g1, 128, %g1
72	membar		#Sync
73	stda		%f32, [%g2 + %g1] ASI_BLK_P
74
75	stda		%f48, [%g3 + %g1] ASI_BLK_P
765:	membar		#Sync
77	ba,pt		%xcc, 80f
78	 nop
79
80	.align		32
8180:	jmpl		%g7 + %g0, %g0
82	 nop
83ENDPROC(VISenter)
84EXPORT_SYMBOL(VISenter)
85