xref: /netbsd-src/sys/arch/arm/pic/pic_splfuncs.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: pic_splfuncs.c,v 1.20 2021/03/27 12:15:09 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 #include <sys/cdefs.h>
31 __KERNEL_RCSID(0, "$NetBSD: pic_splfuncs.c,v 1.20 2021/03/27 12:15:09 jmcneill Exp $");
32 
33 #define _INTR_PRIVATE
34 #include <sys/param.h>
35 #include <sys/atomic.h>
36 #include <sys/evcnt.h>
37 #include <sys/lwp.h>
38 #include <sys/kernel.h>
39 
40 #include <dev/cons.h>
41 
42 #include <arm/armreg.h>
43 #include <arm/cpu.h>
44 #include <arm/cpufunc.h>
45 #include <arm/locore.h>	/* for compat aarch64 */
46 
47 #include <arm/pic/picvar.h>
48 
49 
50 int
51 _splraise(int newipl)
52 {
53 	struct cpu_info * const ci = curcpu();
54 	const int oldipl = ci->ci_cpl;
55 	KASSERT(newipl < NIPL);
56 	if (newipl > ci->ci_cpl) {
57 		pic_set_priority(ci, newipl);
58 	}
59 	return oldipl;
60 }
61 int
62 _spllower(int newipl)
63 {
64 	struct cpu_info * const ci = curcpu();
65 	const int oldipl = ci->ci_cpl;
66 	KASSERT(panicstr || newipl <= ci->ci_cpl);
67 	if (newipl < ci->ci_cpl) {
68 		register_t psw = DISABLE_INTERRUPT_SAVE();
69 		ci->ci_intr_depth++;
70 		pic_do_pending_ints(psw, newipl, NULL);
71 		ci->ci_intr_depth--;
72 		if ((psw & I32_bit) == 0 || newipl == IPL_NONE)
73 			ENABLE_INTERRUPT();
74 		cpu_dosoftints();
75 	}
76 	return oldipl;
77 }
78 
79 void
80 splx(int savedipl)
81 {
82 	struct cpu_info * const ci = curcpu();
83 	KASSERT(savedipl < NIPL);
84 
85 	if (__predict_false(savedipl == ci->ci_cpl)) {
86 		return;
87 	}
88 
89 	register_t psw = DISABLE_INTERRUPT_SAVE();
90 	KASSERTMSG(panicstr != NULL || savedipl < ci->ci_cpl,
91 	    "splx(%d) to a higher ipl than %d", savedipl, ci->ci_cpl);
92 
93 	ci->ci_intr_depth++;
94 	pic_do_pending_ints(psw, savedipl, NULL);
95 	ci->ci_intr_depth--;
96 	KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
97 	    ci->ci_cpl, savedipl);
98 	if ((psw & I32_bit) == 0)
99 		ENABLE_INTERRUPT();
100 	cpu_dosoftints();
101 	KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
102 	    ci->ci_cpl, savedipl);
103 }
104