sys/arch/powerpc/pic/pic_soft.c

   1 /*      $NetBSD: pic_soft.c,v 1.2 2007/10/17 19:56:46 garbled Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2007 Matt Thomas
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of The NetBSD Foundation nor the names of its
  16  *    contributors may be used to endorse or promote products derived
  17  *    from this software without specific prior written permission.
  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 __KERNEL_RCSID(0, "$NetBSD: pic_soft.c,v 1.2 2007/10/17 19:56:46 garbled Exp $");
  34
  35 #include <sys/param.h>
  36 #include <sys/malloc.h>
  37 #include <sys/kernel.h>
  38
  39 #include <uvm/uvm_extern.h>
  40
  41 #include <machine/intr.h>
  42 #include <arch/powerpc/pic/picvar.h>
  43
  44
  45 #define SOFTMASK ((1 << IPL_SOFTCLOCK) |\
  46                   (1 << IPL_SOFTNET) |\
  47                   (1 << IPL_SOFTI2C) |\
  48                   (1 << IPL_SOFTSERIAL))
  49
  50 static void softpic_enable_irq(struct pic_ops *, int, int);
  51 static void softpic_disable_irq(struct pic_ops *, int);
  52 static int  softpic_get_irq(struct pic_ops *);
  53 static void softpic_source_name(struct pic_ops*, int, char *, size_t);
  54
  55 static struct softpic_ops {
  56         struct pic_ops pic;
  57         uint32_t enable_mask;
  58         uint32_t pending;
  59 } softpic = {
  60         .pic = {
  61                 .pic_numintrs = NIPL,
  62                 .pic_enable_irq = softpic_enable_irq,
  63                 .pic_reenable_irq = softpic_enable_irq,
  64                 .pic_disable_irq = softpic_disable_irq,
  65                 .pic_get_irq = softpic_get_irq,
  66                 .pic_source_name = softpic_source_name,
  67                 .pic_name = "soft",
  68         },
  69 };
  70
  71 void
  72 setup_softpic(void)
  73 {
  74         struct pic_ops * const pic = &softpic.pic;
  75
  76         pic_add(pic);
  77
  78         intr_establish(pic->pic_intrbase + IPL_SOFTCLOCK, IST_SOFT,
  79             IPL_SOFTCLOCK, (int (*)(void *))softintr__run,
  80             (void *)IPL_SOFTCLOCK);
  81         intr_establish(pic->pic_intrbase + IPL_SOFTNET, IST_SOFT,
  82             IPL_SOFTNET, (int (*)(void *))softintr__run,
  83             (void *)IPL_SOFTNET);
  84         intr_establish(pic->pic_intrbase + IPL_SOFTI2C, IST_SOFT,
  85             IPL_SOFTI2C, (int (*)(void *))softintr__run,
  86             (void *)IPL_SOFTI2C);
  87         intr_establish(pic->pic_intrbase + IPL_SOFTSERIAL, IST_SOFT,
  88             IPL_SOFTSERIAL, (int (*)(void *))softintr__run,
  89             (void *)IPL_SOFTSERIAL);
  90 }
  91
  92 static void
  93 softpic_source_name(struct pic_ops *pic, int irq, char *name, size_t len)
  94 {
  95         switch (irq) {
  96         case IPL_SOFTSERIAL:    strlcpy(name, "serial", len); break;
  97         case IPL_SOFTNET:       strlcpy(name, "net", len); break;
  98         case IPL_SOFTI2C:       strlcpy(name, "i2c", len); break;
  99         case IPL_SOFTCLOCK:     strlcpy(name, "clock", len); break;
 100         };
 101 }
 102
 103 static void
 104 softpic_enable_irq(struct pic_ops *pic, int irq, int type)
 105 {
 106         struct softpic_ops * const soft = (void *) pic;
 107         soft->enable_mask |= 1 << irq;
 108         if (soft->pending & soft->enable_mask)
 109                 pic_mark_pending(pic->pic_intrbase + irq);
 110 }
 111
 112 static void
 113 softpic_disable_irq(struct pic_ops *pic, int irq)
 114 {
 115         struct softpic_ops * const soft = (void *) pic;
 116         soft->enable_mask &= ~(1 << irq);
 117 }
 118
 119 static int
 120 softpic_get_irq(struct pic_ops *pic)
 121 {
 122         struct softpic_ops * const soft = (void *) pic;
 123         uint32_t old, new;
 124         int ipl;
 125
 126         while (((old = soft->pending) & soft->enable_mask) != 0) {
 127                 /* use cntlzw instead of ffs since we want higher IPLs first */
 128                 ipl = 32 - __builtin_clz(old & soft->enable_mask);
 129                 if (ipl == 0)
 130                         return NO_IRQ;
 131                 new = old & ~(1 << ipl);
 132                 if (cas32(&soft->pending, old, new))
 133                         return ipl;
 134         }
 135
 136         return NO_IRQ;
 137 }
 138
 139 void
 140 softintr(int ipl)
 141 {
 142         KASSERT((1 << ipl) & SOFTMASK);
 143
 144         for (;;) {
 145                 uint32_t old = softpic.pending;
 146                 uint32_t new = old | (1 << ipl);
 147                 if (cas32(&softpic.pending, old, new)) {
 148                         pic_handle_intr(&softpic);
 149                         return;
 150                 }
 151         }
 152 }