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 /* if an mdp_irq's irqmask has changed, such as when mdp5 crtc<->encoder
  46  * link changes, this must be called to figure out the new global irqmask
  47  */
  48 void mdp_irq_update(struct mdp_kms *mdp_kms)
  49 {
  50         unsigned long flags;
  51         spin_lock_irqsave(&list_lock, flags);
  52         update_irq(mdp_kms);
  53         spin_unlock_irqrestore(&list_lock, flags);
  54 }
  55
  56 void mdp_dispatch_irqs(struct mdp_kms *mdp_kms, uint32_t status)
  57 {
  58         struct mdp_irq *handler, *n;
  59         unsigned long flags;
  60
  61         spin_lock_irqsave(&list_lock, flags);
  62         mdp_kms->in_irq = true;
  63         list_for_each_entry_safe(handler, n, &mdp_kms->irq_list, node) {
  64                 if (handler->irqmask & status) {
  65                         spin_unlock_irqrestore(&list_lock, flags);
  66                         handler->irq(handler, handler->irqmask & status);
  67                         spin_lock_irqsave(&list_lock, flags);
  68                 }
  69         }
  70         mdp_kms->in_irq = false;
  71         update_irq(mdp_kms);
  72         spin_unlock_irqrestore(&list_lock, flags);
  73
  74 }
  75
  76 void mdp_update_vblank_mask(struct mdp_kms *mdp_kms, uint32_t mask, bool enable)
  77 {
  78         unsigned long flags;
  79
  80         spin_lock_irqsave(&list_lock, flags);
  81         if (enable)
  82                 mdp_kms->vblank_mask |= mask;
  83         else
  84                 mdp_kms->vblank_mask &= ~mask;
  85         update_irq(mdp_kms);
  86         spin_unlock_irqrestore(&list_lock, flags);
  87 }
  88
  89 static void wait_irq(struct mdp_irq *irq, uint32_t irqstatus)
  90 {
  91         struct mdp_irq_wait *wait =
  92                         container_of(irq, struct mdp_irq_wait, irq);
  93         wait->count--;
  94         wake_up_all(&wait_event);
  95 }
  96
  97 void mdp_irq_wait(struct mdp_kms *mdp_kms, uint32_t irqmask)
  98 {
  99         struct mdp_irq_wait wait = {
 100                 .irq = {
 101                         .irq = wait_irq,
 102                         .irqmask = irqmask,
 103                 },
 104                 .count = 1,
 105         };
 106         mdp_irq_register(mdp_kms, &wait.irq);
 107         wait_event_timeout(wait_event, (wait.count <= 0),
 108                         msecs_to_jiffies(100));
 109         mdp_irq_unregister(mdp_kms, &wait.irq);
 110 }
 111
 112 void mdp_irq_register(struct mdp_kms *mdp_kms, struct mdp_irq *irq)
 113 {
 114         unsigned long flags;
 115         bool needs_update = false;
 116
 117         spin_lock_irqsave(&list_lock, flags);
 118
 119         if (!irq->registered) {
 120                 irq->registered = true;
 121                 list_add(&irq->node, &mdp_kms->irq_list);
 122                 needs_update = !mdp_kms->in_irq;
 123         }
 124
 125         spin_unlock_irqrestore(&list_lock, flags);
 126
 127         if (needs_update)
 128                 mdp_irq_update(mdp_kms);
 129 }
 130
 131 void mdp_irq_unregister(struct mdp_kms *mdp_kms, struct mdp_irq *irq)
 132 {
 133         unsigned long flags;
 134         bool needs_update = false;
 135
 136         spin_lock_irqsave(&list_lock, flags);
 137
 138         if (irq->registered) {
 139                 irq->registered = false;
 140                 list_del(&irq->node);
 141                 needs_update = !mdp_kms->in_irq;
 142         }
 143
 144         spin_unlock_irqrestore(&list_lock, flags);
 145
 146         if (needs_update)
 147                 mdp_irq_update(mdp_kms);
 148 }