drivers/gpu/drm/msm/mdp/mdp_kms.c

   1 /*
   2  * Copyright (C) 2013 Red Hat
   3  * Author: Rob Clark <robdclark@gmail.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18
  19 #include "msm_drv.h"
  20 #include "mdp_kms.h"
  21
  22
  23 struct mdp_irq_wait {
  24         struct mdp_irq irq;
  25         int count;
  26 };
  27
  28 static DECLARE_WAIT_QUEUE_HEAD(wait_event);
  29
  30 static DEFINE_SPINLOCK(list_lock);
  31
  32 static void update_irq(struct mdp_kms *mdp_kms)
  33 {
  34         struct mdp_irq *irq;
  35         uint32_t irqmask = mdp_kms->vblank_mask;
  36
  37         BUG_ON(!spin_is_locked(&list_lock));
  38
  39         list_for_each_entry(irq, &mdp_kms->irq_list, node)
  40                 irqmask |= irq->irqmask;
  41
  42         mdp_kms->funcs->set_irqmask(mdp_kms, irqmask);
  43 }
  44
  45 static void update_irq_unlocked(struct mdp_kms *mdp_kms)
  46 {
  47         unsigned long flags;
  48         spin_lock_irqsave(&list_lock, flags);
  49         update_irq(mdp_kms);
  50         spin_unlock_irqrestore(&list_lock, flags);
  51 }
  52
  53 void mdp_dispatch_irqs(struct mdp_kms *mdp_kms, uint32_t status)
  54 {
  55         struct mdp_irq *handler, *n;
  56         unsigned long flags;
  57
  58         spin_lock_irqsave(&list_lock, flags);
  59         mdp_kms->in_irq = true;
  60         list_for_each_entry_safe(handler, n, &mdp_kms->irq_list, node) {
  61                 if (handler->irqmask & status) {
  62                         spin_unlock_irqrestore(&list_lock, flags);
  63                         handler->irq(handler, handler->irqmask & status);
  64                         spin_lock_irqsave(&list_lock, flags);
  65                 }
  66         }
  67         mdp_kms->in_irq = false;
  68         update_irq(mdp_kms);
  69         spin_unlock_irqrestore(&list_lock, flags);
  70
  71 }
  72
  73 void mdp_update_vblank_mask(struct mdp_kms *mdp_kms, uint32_t mask, bool enable)
  74 {
  75         unsigned long flags;
  76
  77         spin_lock_irqsave(&list_lock, flags);
  78         if (enable)
  79                 mdp_kms->vblank_mask |= mask;
  80         else
  81                 mdp_kms->vblank_mask &= ~mask;
  82         update_irq(mdp_kms);
  83         spin_unlock_irqrestore(&list_lock, flags);
  84 }
  85
  86 static void wait_irq(struct mdp_irq *irq, uint32_t irqstatus)
  87 {
  88         struct mdp_irq_wait *wait =
  89                         container_of(irq, struct mdp_irq_wait, irq);
  90         wait->count--;
  91         wake_up_all(&wait_event);
  92 }
  93
  94 void mdp_irq_wait(struct mdp_kms *mdp_kms, uint32_t irqmask)
  95 {
  96         struct mdp_irq_wait wait = {
  97                 .irq = {
  98                         .irq = wait_irq,
  99                         .irqmask = irqmask,
 100                 },
 101                 .count = 1,
 102         };
 103         mdp_irq_register(mdp_kms, &wait.irq);
 104         wait_event(wait_event, (wait.count <= 0));
 105         mdp_irq_unregister(mdp_kms, &wait.irq);
 106 }
 107
 108 void mdp_irq_register(struct mdp_kms *mdp_kms, struct mdp_irq *irq)
 109 {
 110         unsigned long flags;
 111         bool needs_update = false;
 112
 113         spin_lock_irqsave(&list_lock, flags);
 114
 115         if (!irq->registered) {
 116                 irq->registered = true;
 117                 list_add(&irq->node, &mdp_kms->irq_list);
 118                 needs_update = !mdp_kms->in_irq;
 119         }
 120
 121         spin_unlock_irqrestore(&list_lock, flags);
 122
 123         if (needs_update)
 124                 update_irq_unlocked(mdp_kms);
 125 }
 126
 127 void mdp_irq_unregister(struct mdp_kms *mdp_kms, struct mdp_irq *irq)
 128 {
 129         unsigned long flags;
 130         bool needs_update = false;
 131
 132         spin_lock_irqsave(&list_lock, flags);
 133
 134         if (irq->registered) {
 135                 irq->registered = false;
 136                 list_del(&irq->node);
 137                 needs_update = !mdp_kms->in_irq;
 138         }
 139
 140         spin_unlock_irqrestore(&list_lock, flags);
 141
 142         if (needs_update)
 143                 update_irq_unlocked(mdp_kms);
 144 }