xref: /netbsd-src/sys/arch/arm/pic/pic_splfuncs.c (revision d909946ca08dceb44d7d0f22ec9488679695d976)
1 /*	$NetBSD: pic_splfuncs.c,v 1.7 2015/04/02 03:11:34 matt 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 1.7 2015/04/02 03:11:34 matt 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 #if defined(__arm__)
43 #include <arm/armreg.h>
44 #include <arm/cpu.h>
45 #include <arm/cpufunc.h>
46 #elif defined(__aarch64__)
47 #include <aarch64/locore.h>
48 #define I32_bit		DAIF_I
49 #define F32_bit		DAIF_F
50 #endif
51 
52 #include <arm/pic/picvar.h>
53 
54 
55 int
56 _splraise(int newipl)
57 {
58 	struct cpu_info * const ci = curcpu();
59 	const int oldipl = ci->ci_cpl;
60 	KASSERT(newipl < NIPL);
61 	if (newipl > ci->ci_cpl) {
62 		pic_set_priority(ci, newipl);
63 	}
64 	return oldipl;
65 }
66 int
67 _spllower(int newipl)
68 {
69 	struct cpu_info * const ci = curcpu();
70 	const int oldipl = ci->ci_cpl;
71 	KASSERT(panicstr || newipl <= ci->ci_cpl);
72 	if (newipl < ci->ci_cpl) {
73 		register_t psw = cpsid(I32_bit);
74 		ci->ci_intr_depth++;
75 		pic_do_pending_ints(psw, newipl, NULL);
76 		ci->ci_intr_depth--;
77 		if ((psw & I32_bit) == 0 || newipl == IPL_NONE)
78 			cpsie(I32_bit);
79 		cpu_dosoftints();
80 	}
81 	return oldipl;
82 }
83 
84 void
85 splx(int savedipl)
86 {
87 	struct cpu_info * const ci = curcpu();
88 	KASSERT(savedipl < NIPL);
89 
90 	if (__predict_false(savedipl == ci->ci_cpl)) {
91 		return;
92 	}
93 
94 	register_t psw = cpsid(I32_bit);
95 	KASSERTMSG(panicstr != NULL || savedipl < ci->ci_cpl,
96 	    "splx(%d) to a higher ipl than %d", savedipl, ci->ci_cpl);
97 
98 	ci->ci_intr_depth++;
99 	pic_do_pending_ints(psw, savedipl, NULL);
100 	ci->ci_intr_depth--;
101 	KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
102 	    ci->ci_cpl, savedipl);
103 	if ((psw & I32_bit) == 0)
104 		cpsie(I32_bit);
105 	cpu_dosoftints();
106 	KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
107 	    ci->ci_cpl, savedipl);
108 }
109