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pic_splfuncs.c revision 1.17 
      1 /*	$NetBSD: pic_splfuncs.c,v 1.17 2021/02/21 17:07:45 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 1.17 2021/02/21 17:07:45 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 int
     50 _splraise(int newipl)
     51 {
     52 	struct cpu_info * const ci = curcpu();
     53 	const int oldipl = ci->ci_cpl;
     54 	KASSERT(newipl < NIPL);
     55 	if (newipl > ci->ci_cpl) {
     56 		pic_set_priority(ci, newipl);
     57 	}
     58 	return oldipl;
     59 }
     60 int
     61 _spllower(int newipl)
     62 {
     63 	struct cpu_info * const ci = curcpu();
     64 	const int oldipl = ci->ci_cpl;
     65 	KASSERT(panicstr || newipl <= ci->ci_cpl);
     66 	if (newipl < ci->ci_cpl) {
     67 		register_t psw = cpsid(I32_bit);
     68 		ci->ci_intr_depth++;
     69 		pic_do_pending_ints(psw, newipl, NULL);
     70 		ci->ci_intr_depth--;
     71 		if ((psw & I32_bit) == 0 || newipl == IPL_NONE)
     72 			cpsie(I32_bit);
     73 		cpu_dosoftints();
     74 	}
     75 	return oldipl;
     76 }
     77 
     78 void
     79 splx(int savedipl)
     80 {
     81 	struct cpu_info * const ci = curcpu();
     82 	KASSERT(savedipl < NIPL);
     83 
     84 	if (__predict_false(savedipl == ci->ci_cpl)) {
     85 		return;
     86 	}
     87 
     88 #if defined(__HAVE_PIC_PENDING_INTRS)
     89 	if (__predict_true(ci->ci_pending_ipls == 0)) {
     90 		goto skip_pending;
     91 	}
     92 
     93 	const register_t psw = cpsid(I32_bit);
     94 	ci->ci_intr_depth++;
     95 	while ((ci->ci_pending_ipls & ~__BIT(savedipl)) > __BIT(savedipl)) {
     96 		KASSERT(ci->ci_pending_ipls < __BIT(NIPL));
     97 		for (;;) {
     98 			int ipl = 31 - __builtin_clz(ci->ci_pending_ipls);
     99 			KASSERT(ipl < NIPL);
    100 			if (ipl <= savedipl) {
    101 				break;
    102 			}
    103 
    104 			pic_set_priority(ci, ipl);
    105 			pic_list_deliver_irqs(ci, psw, ipl, NULL);
    106 			pic_list_unblock_irqs(ci);
    107 		}
    108 	}
    109 	ci->ci_intr_depth--;
    110 	if ((psw & I32_bit) == 0) {
    111 		cpsie(I32_bit);
    112 	}
    113 skip_pending:
    114 #endif
    115 
    116 	pic_set_priority(ci, savedipl);
    117 #if defined(__HAVE_CPU_DOSOFTINTS_CI)
    118 	cpu_dosoftints_ci(ci);
    119 #else
    120 	cpu_dosoftints();
    121 #endif
    122 
    123 	KASSERTMSG(ci->ci_cpl == savedipl, "cpl %d savedipl %d",
    124 	    ci->ci_cpl, savedipl);
    125 }
    126