xref: /netbsd-src/sys/arch/riscv/riscv/softint_machdep.c (revision 75b842b84762e0251223b719bf77fbef2e651bf6)
1 /*	$NetBSD: softint_machdep.c,v 1.3 2023/05/07 12:41:49 skrll Exp $	*/
2 
3 /*-
4  * Copyright (c) 2014 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Matt Thomas of 3am Software Foundry.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 
34 __RCSID("$NetBSD: softint_machdep.c,v 1.3 2023/05/07 12:41:49 skrll Exp $");
35 
36 #define __INTR_PRIVATE
37 
38 #include <sys/param.h>
39 #include <sys/intr.h>
40 
41 #include <riscv/locore.h>
42 
43 #ifdef __HAVE_FAST_SOFTINTS
44 
45 #define	SOFTINT2IPLMAP \
46 	(((IPL_SOFTSERIAL - IPL_SOFTCLOCK) << (SOFTINT_SERIAL * 4)) | \
47 	 ((IPL_SOFTNET    - IPL_SOFTCLOCK) << (SOFTINT_NET    * 4)) | \
48 	 ((IPL_SOFTBIO    - IPL_SOFTCLOCK) << (SOFTINT_BIO    * 4)) | \
49 	 ((IPL_SOFTCLOCK  - IPL_SOFTCLOCK) << (SOFTINT_CLOCK  * 4)))
50 #define	SOFTINT2IPL(l)	((SOFTINT2IPLMAP >> ((l) * 4)) & 0x0f)
51 
52 /*
53  * This returns a mask of softint IPLs that be dispatch at <ipl>
54  * SOFTIPLMASK(IPL_NONE)	= 0x0000000f
55  * SOFTIPLMASK(IPL_SOFTCLOCK)	= 0x0000000e
56  * SOFTIPLMASK(IPL_SOFTBIO)	= 0x0000000c
57  * SOFTIPLMASK(IPL_SOFTNET)	= 0x00000008
58  * SOFTIPLMASK(IPL_SOFTSERIAL)	= 0x00000000
59  */
60 #define	SOFTIPLMASK(ipl) ((0x0f << (ipl)) & 0x0f)
61 
62 void softint_switch(lwp_t *, int);
63 
64 void
softint_trigger(uintptr_t mask)65 softint_trigger(uintptr_t mask)
66 {
67 	curcpu()->ci_softints |= mask;
68 }
69 
70 void
softint_init_md(lwp_t * l,u_int level,uintptr_t * machdep)71 softint_init_md(lwp_t *l, u_int level, uintptr_t *machdep)
72 {
73 	lwp_t ** lp = &l->l_cpu->ci_softlwps[level];
74 	KASSERT(*lp == NULL || *lp == l);
75 	*lp = l;
76 	*machdep = 1 << SOFTINT2IPL(level);
77 	KASSERT(level != SOFTINT_CLOCK || *machdep == (1 << (IPL_SOFTCLOCK - IPL_SOFTCLOCK)));
78 	KASSERT(level != SOFTINT_BIO || *machdep == (1 << (IPL_SOFTBIO - IPL_SOFTCLOCK)));
79 	KASSERT(level != SOFTINT_NET || *machdep == (1 << (IPL_SOFTNET - IPL_SOFTCLOCK)));
80 	KASSERT(level != SOFTINT_SERIAL || *machdep == (1 << (IPL_SOFTSERIAL - IPL_SOFTCLOCK)));
81 }
82 
83 void
softint_deliver(void)84 softint_deliver(void)
85 {
86 	struct cpu_info * const ci = curcpu();
87 	const int opl = ci->ci_cpl;
88 	const uint32_t softiplmask = SOFTIPLMASK(opl);
89 
90 	splhigh();
91 	for (;;) {
92 		u_int softints = ci->ci_softints & softiplmask;
93 		KASSERT((softints != 0) == ((ci->ci_softints >> opl) != 0));
94 		KASSERT(opl == IPL_NONE || (softints & (1 << (opl - IPL_SOFTCLOCK))) == 0);
95 		if (softints == 0) {
96 			splx(opl);
97 			return;
98 		}
99 #define	DOSOFTINT(n) \
100 		if (ci->ci_softints & (1 << (IPL_SOFT ## n - IPL_SOFTCLOCK))) { \
101 			ci->ci_softints &= \
102 			    ~(1 << (IPL_SOFT ## n - IPL_SOFTCLOCK)); \
103 			cpu_fast_switchto(ci->ci_softlwps[SOFTINT_ ## n], \
104 			    IPL_SOFT ## n); \
105 			continue; \
106 		}
107 		DOSOFTINT(SERIAL);
108 		DOSOFTINT(NET);
109 		DOSOFTINT(BIO);
110 		DOSOFTINT(CLOCK);
111 		panic("dosoftints wtf (softints=%u?, ipl=%d)", softints, opl);
112 	}
113 }
114 #endif /* __HAVE_FAST_SOFTINTS */
115