xref: /netbsd-src/sys/arch/arm/pic/pic_splfuncs.c (revision a24ea6034e91a5a146b0069477432726f471d594)
1 /*	$NetBSD: pic_splfuncs.c,v 1.24 2022/06/25 13:24:35 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 1.24 2022/06/25 13:24:35 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 int
_splraise(int newipl)53 _splraise(int newipl)
54 {
55 	struct cpu_info * const ci = curcpu();
56 	const int oldipl = ci->ci_cpl;
57 	KASSERT(newipl < NIPL);
58 	if (newipl > ci->ci_cpl) {
59 		pic_set_priority(ci, newipl);
60 	}
61 	return oldipl;
62 }
63 
64 int
_spllower(int newipl)65 _spllower(int newipl)
66 {
67 	struct cpu_info * const ci = curcpu();
68 	const int oldipl = ci->ci_cpl;
69 	KASSERT(panicstr || newipl <= ci->ci_cpl);
70 	if (newipl < ci->ci_cpl) {
71 		register_t psw = DISABLE_INTERRUPT_SAVE();
72 		ci->ci_intr_depth++;
73 		pic_do_pending_ints(psw, newipl, NULL);
74 		ci->ci_intr_depth--;
75 		if ((psw & I32_bit) == 0 || newipl == IPL_NONE)
76 			ENABLE_INTERRUPT();
77 		cpu_dosoftints();
78 	}
79 	return oldipl;
80 }
81 
82 void
splx(int savedipl)83 splx(int savedipl)
84 {
85 	struct cpu_info * const ci = curcpu();
86 	KASSERT(savedipl < NIPL);
87 
88 	if (__predict_false(savedipl == ci->ci_cpl)) {
89 		return;
90 	}
91 
92 	if (ci->ci_cpl >= IPL_VM) {
93 		register_t psw = DISABLE_INTERRUPT_SAVE();
94 		KASSERTMSG(panicstr != NULL || savedipl < ci->ci_cpl,
95 		    "splx(%d) to a higher ipl than %d", savedipl, ci->ci_cpl);
96 
97 		ci->ci_intr_depth++;
98 		pic_do_pending_ints(psw, savedipl, NULL);
99 		ci->ci_intr_depth--;
100 		KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
101 		    ci->ci_cpl, savedipl);
102 		if ((psw & I32_bit) == 0)
103 			ENABLE_INTERRUPT();
104 	} else {
105 		pic_set_priority(ci, savedipl);
106 	}
107 
108 	cpu_dosoftints();
109 	KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
110 	    ci->ci_cpl, savedipl);
111 }
112