1/*
2 * Copyright (c) 2011 Aeroflex Gaisler
3 *
4 * BSD license:
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25
26#include <asm-leon/leonstack.h>
27#include <asm-leon/winmacros.h>
28
29/* Registers to not touch at all. */
30#define t_psr        l0 /* Set by caller */
31#define t_pc         l1 /* Set by caller */
32#define t_npc        l2 /* Set by caller */
33#define t_wim        l3 /* Set by caller */
34#define t_twinmask   l4 /* Set at beginning of this entry routine. */
35#define t_kstack     l5 /* Set right before pt_regs frame is built */
36#define t_retpc      l6 /* If you change this, change winmacro.h header file */
37#define t_systable   l7 /* Never touch this, could be the syscall table ptr. */
38#define curptr       g6 /* Set after pt_regs frame is built */
39
40	/* Number of register windows */
41	.global _nwindows_min1, _nwindows
42
43        .text
44	.align 4
45	.globl	leonbare_trapsetup_fast
46
47/* etap entry special for irqtrap.S */
48leonbare_trapsetup_fast:
49
50#ifdef 	_FLAT
51	restore
52	RW_STORE(sp)
53	save
54#endif
55
56#ifndef _SOFT_FLOAT
57	/* build a pt_regs trap frame. */
58        sub	%fp, (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ), %t_kstack
59	st 	%t_psr, [%t_kstack + (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ - 8)] /* sparc_fpuwindow_regs.irqpsr  */
60
61	set	SPARC_PSR_EF_MASK, %t_twinmask
62	andn	%t_psr, %t_twinmask, %t_psr	          ! fpu off
63
64	PT_STORE_ALL_FAST(t_kstack, t_psr, t_pc, t_npc, g2)
65        /*PT_STORE_GLOBALS(t_kstack)*/
66
67	/* build a fp_regs trap frame. */
68	sethi %hi(fpustate_current), %g2
69	ld [%g2+%lo(fpustate_current)], %g3
70	st %g3,[%t_kstack + (SF_REGS_SZ + PT_REGS_SZ + FW_REGS_SZ - 4)]    /* sparc_fpuwindow_regs.lastctx */
71	add %t_kstack,SF_REGS_SZ + PT_REGS_SZ,%g3
72	st 	%g3, [%g2+%lo(fpustate_current)]
73	st	%g0, [%g3 + FW_FSR]
74#else
75	/* build a pt_regs trap frame.
76	 */
77        sub	%fp, (SF_REGS_SZ + PT_REGS_SZ), %t_kstack
78	PT_STORE_ALL_FAST(t_kstack, t_psr, t_pc, t_npc, g2)
79	/*PT_STORE_GLOBALS(t_kstack)*/
80#endif
81
82
83#ifndef _FLAT
84        /* See if we are in the trap window . */
85	mov	1, %t_twinmask
86	sll	%t_twinmask, %t_psr, %t_twinmask ! t_twinmask = (1 << psr)
87	andcc	%t_twinmask, %t_wim, %g0
88	beq	1f		! in trap window, clean up
89	 nop
90
91                /*-------------------------------------------------*/
92                /* Spill , adjust %wim and go. */
93                srl	%t_wim, 0x1, %g2	! begin computation of new %wim
94
95		sethi %hi(_nwindows_min1), %g3
96		ld [%g3+%lo(_nwindows_min1)], %g3
97
98                sll	%t_wim, %g3, %t_wim	! NWINDOWS-1
99                or	%t_wim, %g2, %g2
100                and	%g2, 0xff, %g2
101
102                save	%g0, %g0, %g0           ! get in window to be saved
103
104        	/* Set new %wim value */
105                wr	%g2, 0x0, %wim
106
107        	/* Save the kernel window onto the corresponding stack. */
108                RW_STORE(sp)
109
110        	restore	%g0, %g0, %g0
111                /*-------------------------------------------------*/
112
1131:
114#endif
115	/* Trap from kernel with a window available.
116	 * Just do it...
117	 */
118	jmpl	%t_retpc + 0x8, %g0	! return to caller
119	 mov	%t_kstack, %sp		! jump onto new stack
120
121
122