Home | History | Annotate | Line # | Download | only in pic
pic_splfuncs.c revision 1.19 
      1 /*	$NetBSD: pic_splfuncs.c,v 1.19 2021/03/01 11:29:14 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 1.19 2021/03/01 11:29:14 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 #if defined(__HAVE_CPU_DOSOFTINTS_CI)
     50 #define	CPU_DOSOFTINTS(ci)	cpu_dosoftints_ci((ci))
     51 #else
     52 #define	CPU_DOSOFTINTS(ci)	cpu_dosoftints()
     53 #endif
     54 
     55 #if defined(__HAVE_PIC_PENDING_INTRS)
     56 static void	splx_dopendingints(struct cpu_info *, const int);
     57 #endif
     58 
     59 int
     60 _splraise(int newipl)
     61 {
     62 	struct cpu_info * const ci = curcpu();
     63 	const int oldipl = ci->ci_cpl;
     64 	KDASSERT(newipl < NIPL);
     65 	if (newipl > ci->ci_cpl) {
     66 		pic_set_priority(ci, newipl);
     67 	}
     68 	return oldipl;
     69 }
     70 
     71 int
     72 _spllower(int newipl)
     73 {
     74 	struct cpu_info * const ci = curcpu();
     75 	const int oldipl = ci->ci_cpl;
     76 	KDASSERT(panicstr || newipl <= ci->ci_cpl);
     77 	if (newipl < ci->ci_cpl) {
     78 		register_t psw = DISABLE_INTERRUPT_SAVE();
     79 		ci->ci_intr_depth++;
     80 		pic_do_pending_ints(psw, newipl, NULL);
     81 		ci->ci_intr_depth--;
     82 		if ((psw & I32_bit) == 0 || newipl == IPL_NONE) {
     83 			ENABLE_INTERRUPT();
     84 		}
     85 		cpu_dosoftints();
     86 	}
     87 	return oldipl;
     88 }
     89 
     90 void
     91 splx(int savedipl)
     92 {
     93 	struct cpu_info * const ci = curcpu();
     94 	KDASSERT(savedipl < NIPL);
     95 
     96 	if (__predict_false(savedipl == ci->ci_cpl)) {
     97 		return;
     98 	}
     99 
    100 #if defined(__HAVE_PIC_PENDING_INTRS)
    101 	if (__predict_false(ci->ci_pending_ipls != 0)) {
    102 		splx_dopendingints(ci, savedipl);
    103 	}
    104 #endif
    105 
    106 	pic_set_priority(ci, savedipl);
    107 	CPU_DOSOFTINTS(ci);
    108 
    109 	KDASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
    110 	    ci->ci_cpl, savedipl);
    111 }
    112 
    113 #if defined(__HAVE_PIC_PENDING_INTRS)
    114 static void __noinline
    115 splx_dopendingints(struct cpu_info *ci, const int savedipl)
    116 {
    117 	const register_t psw = DISABLE_INTERRUPT_SAVE();
    118 	ci->ci_intr_depth++;
    119 	while ((ci->ci_pending_ipls & ~__BIT(savedipl)) > __BIT(savedipl)) {
    120 		KASSERT(ci->ci_pending_ipls < __BIT(NIPL));
    121 		for (;;) {
    122 			int ipl = 31 - __builtin_clz(ci->ci_pending_ipls);
    123 			KASSERT(ipl < NIPL);
    124 			if (ipl <= savedipl) {
    125 				break;
    126 			}
    127 
    128 			pic_set_priority(ci, ipl);
    129 			pic_list_deliver_irqs(ci, psw, ipl, NULL);
    130 			pic_list_unblock_irqs(ci);
    131 		}
    132 	}
    133 	ci->ci_intr_depth--;
    134 	if ((psw & I32_bit) == 0) {
    135 		ENABLE_INTERRUPT();
    136 	}
    137 }
    138 #endif
    139