xref: /netbsd-src/sys/arch/arm/pic/pic_splfuncs.c (revision fb5eed702691094bd687fbf1ded189c87457cd35)
1 /*	$NetBSD: pic_splfuncs.c,v 1.22 2021/09/20 21:05:15 jmcneill Exp $	*/
2 /*-
3  * Copyright (c) 2008 The NetBSD Foundation, Inc.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to The NetBSD Foundation
7  * by Matt Thomas.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include "opt_modular.h"
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: pic_splfuncs.c,v 1.22 2021/09/20 21:05:15 jmcneill Exp $");
35 
36 #define _INTR_PRIVATE
37 #include <sys/param.h>
38 #include <sys/atomic.h>
39 #include <sys/evcnt.h>
40 #include <sys/lwp.h>
41 #include <sys/kernel.h>
42 
43 #include <dev/cons.h>
44 
45 #include <arm/armreg.h>
46 #include <arm/cpu.h>
47 #include <arm/cpufunc.h>
48 #include <arm/locore.h>	/* for compat aarch64 */
49 
50 #include <arm/pic/picvar.h>
51 
52 static int	pic_default_splraise(int);
53 static int	pic_default_spllower(int);
54 static void	pic_default_splx(int);
55 
56 int (*pic_splraise)(int) = pic_default_splraise;
57 int (*pic_spllower)(int) = pic_default_spllower;
58 void (*pic_splx)(int) = pic_default_splx;
59 
60 static int
61 pic_default_splraise(int newipl)
62 {
63 	struct cpu_info * const ci = curcpu();
64 	const int oldipl = ci->ci_cpl;
65 	KASSERT(newipl < NIPL);
66 	if (newipl > ci->ci_cpl) {
67 		pic_set_priority(ci, newipl);
68 	}
69 	return oldipl;
70 }
71 
72 static int
73 pic_default_spllower(int newipl)
74 {
75 	struct cpu_info * const ci = curcpu();
76 	const int oldipl = ci->ci_cpl;
77 	KASSERT(panicstr || newipl <= ci->ci_cpl);
78 	if (newipl < ci->ci_cpl) {
79 		register_t psw = DISABLE_INTERRUPT_SAVE();
80 		ci->ci_intr_depth++;
81 		pic_do_pending_ints(psw, newipl, NULL);
82 		ci->ci_intr_depth--;
83 		if ((psw & I32_bit) == 0 || newipl == IPL_NONE)
84 			ENABLE_INTERRUPT();
85 		cpu_dosoftints();
86 	}
87 	return oldipl;
88 }
89 
90 static void
91 pic_default_splx(int savedipl)
92 {
93 	struct cpu_info * const ci = curcpu();
94 	KASSERT(savedipl < NIPL);
95 
96 	if (__predict_false(savedipl == ci->ci_cpl)) {
97 		return;
98 	}
99 
100 	register_t psw = DISABLE_INTERRUPT_SAVE();
101 	KASSERTMSG(panicstr != NULL || savedipl < ci->ci_cpl,
102 	    "splx(%d) to a higher ipl than %d", savedipl, ci->ci_cpl);
103 
104 	ci->ci_intr_depth++;
105 	pic_do_pending_ints(psw, savedipl, NULL);
106 	ci->ci_intr_depth--;
107 	KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
108 	    ci->ci_cpl, savedipl);
109 	if ((psw & I32_bit) == 0)
110 		ENABLE_INTERRUPT();
111 	cpu_dosoftints();
112 	KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
113 	    ci->ci_cpl, savedipl);
114 }
115 
116 #ifdef MODULAR
117 #ifdef _spllower
118 #undef _spllower
119 #endif
120 int _spllower(int);
121 
122 #ifdef _splraise
123 #undef _splraise
124 #endif
125 int _splraise(int);
126 
127 #ifdef splx
128 #undef splx
129 #endif
130 void splx(int);
131 
132 int
133 _spllower(int newipl)
134 {
135 	return pic_spllower(newipl);
136 }
137 
138 int
139 _splraise(int newipl)
140 {
141 	return pic_splraise(newipl);
142 }
143 
144 void
145 splx(int savedipl)
146 {
147 	pic_splx(savedipl);
148 }
149 #endif /* !MODULAR */
150