drm/msm: move irq utils to mdp_kms

We'll want basically the same thing for mdp5, so refactor it out so it
can be shared.

Signed-off-by: Rob Clark <robdclark@gmail.com>

10 files changed, 254 insertions, 169 deletions

diff --git a/drivers/gpu/drm/msm/Makefile b/drivers/gpu/drm/msm/Makefile
index 9481736eb2dd..17847af4e7ab 100644
--- a/drivers/gpu/drm/msm/Makefile
+++ b/drivers/gpu/drm/msm/Makefile
@@ -13,6 +13,7 @@ msm-y := \
         hdmi/hdmi_phy_8960.o \
         hdmi/hdmi_phy_8x60.o \
         mdp/mdp_format.o \
+        mdp/mdp_kms.o \
         mdp/mdp4/mdp4_crtc.o \
         mdp/mdp4/mdp4_dtv_encoder.o \
         mdp/mdp4/mdp4_irq.o \
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c
index c11400a1c603..1964f4f0d452 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c
@@ -66,15 +66,15 @@ struct mdp4_crtc {
         /* for unref'ing cursor bo's after scanout completes: */
         struct drm_flip_work unref_cursor_work;
 
-        struct mdp4_irq vblank;
-        struct mdp4_irq err;
+        struct mdp_irq vblank;
+        struct mdp_irq err;
 };
 #define to_mdp4_crtc(x) container_of(x, struct mdp4_crtc, base)
 
 static struct mdp4_kms *get_kms(struct drm_crtc *crtc)
 {
         struct msm_drm_private *priv = crtc->dev->dev_private;
-        return to_mdp4_kms(priv->kms);
+        return to_mdp4_kms(to_mdp_kms(priv->kms));
 }
 
 static void update_fb(struct drm_crtc *crtc, bool async,
@@ -93,7 +93,7 @@ static void update_fb(struct drm_crtc *crtc, bool async,
 
         if (!async) {
                 /* enable vblank to pick up the old_fb */
-                mdp4_irq_register(get_kms(crtc), &mdp4_crtc->vblank);
+                mdp_irq_register(&get_kms(crtc)->base, &mdp4_crtc->vblank);
         }
 }
 
@@ -145,7 +145,7 @@ static void request_pending(struct drm_crtc *crtc, uint32_t pending)
         struct mdp4_crtc *mdp4_crtc = to_mdp4_crtc(crtc);
 
         atomic_or(pending, &mdp4_crtc->pending);
-        mdp4_irq_register(get_kms(crtc), &mdp4_crtc->vblank);
+        mdp_irq_register(&get_kms(crtc)->base, &mdp4_crtc->vblank);
 }
 
 static void pageflip_cb(struct msm_fence_cb *cb)
@@ -210,9 +210,9 @@ static void mdp4_crtc_dpms(struct drm_crtc *crtc, int mode)
         if (enabled != mdp4_crtc->enabled) {
                 if (enabled) {
                         mdp4_enable(mdp4_kms);
-                        mdp4_irq_register(mdp4_kms, &mdp4_crtc->err);
+                        mdp_irq_register(&mdp4_kms->base, &mdp4_crtc->err);
                 } else {
-                        mdp4_irq_unregister(mdp4_kms, &mdp4_crtc->err);
+                        mdp_irq_unregister(&mdp4_kms->base, &mdp4_crtc->err);
                         mdp4_disable(mdp4_kms);
                 }
                 mdp4_crtc->enabled = enabled;
@@ -571,14 +571,14 @@ static const struct drm_crtc_helper_funcs mdp4_crtc_helper_funcs = {
         .load_lut = mdp4_crtc_load_lut,
 };
 
-static void mdp4_crtc_vblank_irq(struct mdp4_irq *irq, uint32_t irqstatus)
+static void mdp4_crtc_vblank_irq(struct mdp_irq *irq, uint32_t irqstatus)
 {
         struct mdp4_crtc *mdp4_crtc = container_of(irq, struct mdp4_crtc, vblank);
         struct drm_crtc *crtc = &mdp4_crtc->base;
         struct msm_drm_private *priv = crtc->dev->dev_private;
         unsigned pending;
 
-        mdp4_irq_unregister(get_kms(crtc), &mdp4_crtc->vblank);
+        mdp_irq_unregister(&get_kms(crtc)->base, &mdp4_crtc->vblank);
 
         pending = atomic_xchg(&mdp4_crtc->pending, 0);
 
@@ -593,7 +593,7 @@ static void mdp4_crtc_vblank_irq(struct mdp4_irq *irq, uint32_t irqstatus)
         }
 }
 
-static void mdp4_crtc_err_irq(struct mdp4_irq *irq, uint32_t irqstatus)
+static void mdp4_crtc_err_irq(struct mdp_irq *irq, uint32_t irqstatus)
 {
         struct mdp4_crtc *mdp4_crtc = container_of(irq, struct mdp4_crtc, err);
         struct drm_crtc *crtc = &mdp4_crtc->base;
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_dtv_encoder.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_dtv_encoder.c
index 3799ccc517b2..067ed03b35fe 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_dtv_encoder.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_dtv_encoder.c
@@ -35,7 +35,7 @@ struct mdp4_dtv_encoder {
 static struct mdp4_kms *get_kms(struct drm_encoder *encoder)
 {
         struct msm_drm_private *priv = encoder->dev->dev_private;
-        return to_mdp4_kms(priv->kms);
+        return to_mdp4_kms(to_mdp_kms(priv->kms));
 }
 
 #ifdef CONFIG_MSM_BUS_SCALING
@@ -137,7 +137,7 @@ static void mdp4_dtv_encoder_dpms(struct drm_encoder *encoder, int mode)
                  * the settings changes for the new modeset (like new
                  * scanout buffer) don't latch properly..
                  */
-                mdp4_irq_wait(mdp4_kms, MDP4_IRQ_EXTERNAL_VSYNC);
+                mdp_irq_wait(&mdp4_kms->base, MDP4_IRQ_EXTERNAL_VSYNC);
 
                 clk_disable_unprepare(mdp4_dtv_encoder->src_clk);
                 clk_disable_unprepare(mdp4_dtv_encoder->hdmi_clk);
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_irq.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_irq.c
index 5c6b7fca4edd..c740ccd1cc67 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_irq.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_irq.c
@@ -19,77 +19,49 @@
 #include "msm_drv.h"
 #include "mdp4_kms.h"
 
-
-struct mdp4_irq_wait {
-        struct mdp4_irq irq;
-        int count;
-};
-
-static DECLARE_WAIT_QUEUE_HEAD(wait_event);
-
-static DEFINE_SPINLOCK(list_lock);
-
-static void update_irq(struct mdp4_kms *mdp4_kms)
+void mdp4_set_irqmask(struct mdp_kms *mdp_kms, uint32_t irqmask)
 {
-        struct mdp4_irq *irq;
-        uint32_t irqmask = mdp4_kms->vblank_mask;
-
-        BUG_ON(!spin_is_locked(&list_lock));
-
-        list_for_each_entry(irq, &mdp4_kms->irq_list, node)
-                irqmask |= irq->irqmask;
-
-        mdp4_write(mdp4_kms, REG_MDP4_INTR_ENABLE, irqmask);
+        mdp4_write(to_mdp4_kms(mdp_kms), REG_MDP4_INTR_ENABLE, irqmask);
 }
 
-static void update_irq_unlocked(struct mdp4_kms *mdp4_kms)
-{
-        unsigned long flags;
-        spin_lock_irqsave(&list_lock, flags);
-        update_irq(mdp4_kms);
-        spin_unlock_irqrestore(&list_lock, flags);
-}
-
-static void mdp4_irq_error_handler(struct mdp4_irq *irq, uint32_t irqstatus)
+static void mdp4_irq_error_handler(struct mdp_irq *irq, uint32_t irqstatus)
 {
         DRM_ERROR("errors: %08x\n", irqstatus);
 }
 
 void mdp4_irq_preinstall(struct msm_kms *kms)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
+        struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
         mdp4_write(mdp4_kms, REG_MDP4_INTR_CLEAR, 0xffffffff);
 }
 
 int mdp4_irq_postinstall(struct msm_kms *kms)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
-        struct mdp4_irq *error_handler = &mdp4_kms->error_handler;
-
-        INIT_LIST_HEAD(&mdp4_kms->irq_list);
+        struct mdp_kms *mdp_kms = to_mdp_kms(kms);
+        struct mdp4_kms *mdp4_kms = to_mdp4_kms(mdp_kms);
+        struct mdp_irq *error_handler = &mdp4_kms->error_handler;
 
         error_handler->irq = mdp4_irq_error_handler;
         error_handler->irqmask = MDP4_IRQ_PRIMARY_INTF_UDERRUN |
                         MDP4_IRQ_EXTERNAL_INTF_UDERRUN;
 
-        mdp4_irq_register(mdp4_kms, error_handler);
+        mdp_irq_register(mdp_kms, error_handler);
 
         return 0;
 }
 
 void mdp4_irq_uninstall(struct msm_kms *kms)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
+        struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
         mdp4_write(mdp4_kms, REG_MDP4_INTR_ENABLE, 0x00000000);
 }
 
 irqreturn_t mdp4_irq(struct msm_kms *kms)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
+        struct mdp_kms *mdp_kms = to_mdp_kms(kms);
+        struct mdp4_kms *mdp4_kms = to_mdp4_kms(mdp_kms);
         struct drm_device *dev = mdp4_kms->dev;
         struct msm_drm_private *priv = dev->dev_private;
-        struct mdp4_irq *handler, *n;
-        unsigned long flags;
         unsigned int id;
         uint32_t status;
 
@@ -102,102 +74,20 @@ irqreturn_t mdp4_irq(struct msm_kms *kms)
                 if (status & mdp4_crtc_vblank(priv->crtcs[id]))
                         drm_handle_vblank(dev, id);
 
-        spin_lock_irqsave(&list_lock, flags);
-        mdp4_kms->in_irq = true;
-        list_for_each_entry_safe(handler, n, &mdp4_kms->irq_list, node) {
-                if (handler->irqmask & status) {
-                        spin_unlock_irqrestore(&list_lock, flags);
-                        handler->irq(handler, handler->irqmask & status);
-                        spin_lock_irqsave(&list_lock, flags);
-                }
-        }
-        mdp4_kms->in_irq = false;
-        update_irq(mdp4_kms);
-        spin_unlock_irqrestore(&list_lock, flags);
+        mdp_dispatch_irqs(mdp_kms, status);
 
         return IRQ_HANDLED;
 }
 
 int mdp4_enable_vblank(struct msm_kms *kms, struct drm_crtc *crtc)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
-        unsigned long flags;
-
-        spin_lock_irqsave(&list_lock, flags);
-        mdp4_kms->vblank_mask |= mdp4_crtc_vblank(crtc);
-        update_irq(mdp4_kms);
-        spin_unlock_irqrestore(&list_lock, flags);
-
+        mdp_update_vblank_mask(to_mdp_kms(kms),
+                        mdp4_crtc_vblank(crtc), true);
         return 0;
 }
 
 void mdp4_disable_vblank(struct msm_kms *kms, struct drm_crtc *crtc)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
-        unsigned long flags;
-
-        spin_lock_irqsave(&list_lock, flags);
-        mdp4_kms->vblank_mask &= ~mdp4_crtc_vblank(crtc);
-        update_irq(mdp4_kms);
-        spin_unlock_irqrestore(&list_lock, flags);
-}
-
-static void wait_irq(struct mdp4_irq *irq, uint32_t irqstatus)
-{
-        struct mdp4_irq_wait *wait =
-                        container_of(irq, struct mdp4_irq_wait, irq);
-        wait->count--;
-        wake_up_all(&wait_event);
-}
-
-void mdp4_irq_wait(struct mdp4_kms *mdp4_kms, uint32_t irqmask)
-{
-        struct mdp4_irq_wait wait = {
-                .irq = {
-                        .irq = wait_irq,
-                        .irqmask = irqmask,
-                },
-                .count = 1,
-        };
-        mdp4_irq_register(mdp4_kms, &wait.irq);
-        wait_event(wait_event, (wait.count <= 0));
-        mdp4_irq_unregister(mdp4_kms, &wait.irq);
-}
-
-void mdp4_irq_register(struct mdp4_kms *mdp4_kms, struct mdp4_irq *irq)
-{
-        unsigned long flags;
-        bool needs_update = false;
-
-        spin_lock_irqsave(&list_lock, flags);
-
-        if (!irq->registered) {
-                irq->registered = true;
-                list_add(&irq->node, &mdp4_kms->irq_list);
-                needs_update = !mdp4_kms->in_irq;
-        }
-
-        spin_unlock_irqrestore(&list_lock, flags);
-
-        if (needs_update)
-                update_irq_unlocked(mdp4_kms);
-}
-
-void mdp4_irq_unregister(struct mdp4_kms *mdp4_kms, struct mdp4_irq *irq)
-{
-        unsigned long flags;
-        bool needs_update = false;
-
-        spin_lock_irqsave(&list_lock, flags);
-
-        if (irq->registered) {
-                irq->registered = false;
-                list_del(&irq->node);
-                needs_update = !mdp4_kms->in_irq;
-        }
-
-        spin_unlock_irqrestore(&list_lock, flags);
-
-        if (needs_update)
-                update_irq_unlocked(mdp4_kms);
+        mdp_update_vblank_mask(to_mdp_kms(kms),
+                        mdp4_crtc_vblank(crtc), false);
 }
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
index ee4b27eded98..4d1cc2ea700e 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
@@ -24,7 +24,7 @@ static struct mdp4_platform_config *mdp4_get_config(struct platform_device *dev)
 
 static int mdp4_hw_init(struct msm_kms *kms)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
+        struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
         struct drm_device *dev = mdp4_kms->dev;
         uint32_t version, major, minor, dmap_cfg, vg_cfg;
         unsigned long clk;
@@ -133,7 +133,7 @@ static long mdp4_round_pixclk(struct msm_kms *kms, unsigned long rate,
 
 static void mdp4_preclose(struct msm_kms *kms, struct drm_file *file)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
+        struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
         struct msm_drm_private *priv = mdp4_kms->dev->dev_private;
         unsigned i;
 
@@ -143,11 +143,12 @@ static void mdp4_preclose(struct msm_kms *kms, struct drm_file *file)
 
 static void mdp4_destroy(struct msm_kms *kms)
 {
-        struct mdp4_kms *mdp4_kms = to_mdp4_kms(kms);
+        struct mdp4_kms *mdp4_kms = to_mdp4_kms(to_mdp_kms(kms));
         kfree(mdp4_kms);
 }
 
-static const struct msm_kms_funcs kms_funcs = {
+static const struct mdp_kms_funcs kms_funcs = {
+        .base = {
                 .hw_init         = mdp4_hw_init,
                 .irq_preinstall  = mdp4_irq_preinstall,
                 .irq_postinstall = mdp4_irq_postinstall,
@@ -159,6 +160,8 @@ static const struct msm_kms_funcs kms_funcs = {
                 .round_pixclk    = mdp4_round_pixclk,
                 .preclose        = mdp4_preclose,
                 .destroy         = mdp4_destroy,
+        },
+        .set_irqmask         = mdp4_set_irqmask,
 };
 
 int mdp4_disable(struct mdp4_kms *mdp4_kms)
@@ -273,8 +276,9 @@ struct msm_kms *mdp4_kms_init(struct drm_device *dev)
                 goto fail;
         }
 
-        kms = &mdp4_kms->base;
-        kms->funcs = &kms_funcs;
+        mdp_kms_init(&mdp4_kms->base, &kms_funcs);
+
+        kms = &mdp4_kms->base.base;
 
         mdp4_kms->dev = dev;
 
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h
index d5e6819b1f51..66a4d31aec80 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h
@@ -23,22 +23,8 @@
 #include "mdp/mdp_kms.h"
 #include "mdp4.xml.h"
 
-
-/* For transiently registering for different MDP4 irqs that various parts
- * of the KMS code need during setup/configuration.  We these are not
- * necessarily the same as what drm_vblank_get/put() are requesting, and
- * the hysteresis in drm_vblank_put() is not necessarily desirable for
- * internal housekeeping related irq usage.
- */
-struct mdp4_irq {
-        struct list_head node;
-        uint32_t irqmask;
-        bool registered;
-        void (*irq)(struct mdp4_irq *irq, uint32_t irqstatus);
-};
-
 struct mdp4_kms {
-        struct msm_kms base;
+        struct mdp_kms base;
 
         struct drm_device *dev;
 
@@ -57,11 +43,7 @@ struct mdp4_kms {
         struct clk *pclk;
         struct clk *lut_clk;
 
-        /* irq handling: */
-        bool in_irq;
-        struct list_head irq_list;    /* list of mdp4_irq */
-        uint32_t vblank_mask;         /* irq bits set for userspace vblank */
-        struct mdp4_irq error_handler;
+        struct mdp_irq error_handler;
 };
 #define to_mdp4_kms(x) container_of(x, struct mdp4_kms, base)
 
@@ -166,13 +148,11 @@ static inline uint32_t mixercfg(int mixer, enum mdp4_pipe pipe,
 int mdp4_disable(struct mdp4_kms *mdp4_kms);
 int mdp4_enable(struct mdp4_kms *mdp4_kms);
 
+void mdp4_set_irqmask(struct mdp_kms *mdp_kms, uint32_t irqmask);
 void mdp4_irq_preinstall(struct msm_kms *kms);
 int mdp4_irq_postinstall(struct msm_kms *kms);
 void mdp4_irq_uninstall(struct msm_kms *kms);
 irqreturn_t mdp4_irq(struct msm_kms *kms);
-void mdp4_irq_wait(struct mdp4_kms *mdp4_kms, uint32_t irqmask);
-void mdp4_irq_register(struct mdp4_kms *mdp4_kms, struct mdp4_irq *irq);
-void mdp4_irq_unregister(struct mdp4_kms *mdp4_kms, struct mdp4_irq *irq);
 int mdp4_enable_vblank(struct msm_kms *kms, struct drm_crtc *crtc);
 void mdp4_disable_vblank(struct msm_kms *kms, struct drm_crtc *crtc);
 
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c
index d2edf2b2a816..2406027200ec 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c
@@ -34,7 +34,7 @@ struct mdp4_plane {
 static struct mdp4_kms *get_kms(struct drm_plane *plane)
 {
         struct msm_drm_private *priv = plane->dev->dev_private;
-        return to_mdp4_kms(priv->kms);
+        return to_mdp4_kms(to_mdp_kms(priv->kms));
 }
 
 static int mdp4_plane_update(struct drm_plane *plane,
diff --git a/drivers/gpu/drm/msm/mdp/mdp_kms.c b/drivers/gpu/drm/msm/mdp/mdp_kms.c
new file mode 100644
index 000000000000..3be48f7c36be
--- /dev/null
+++ b/drivers/gpu/drm/msm/mdp/mdp_kms.c
@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2013 Red Hat
+ * Author: Rob Clark <robdclark@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include "msm_drv.h"
+#include "mdp_kms.h"
+
+
+struct mdp_irq_wait {
+        struct mdp_irq irq;
+        int count;
+};
+
+static DECLARE_WAIT_QUEUE_HEAD(wait_event);
+
+static DEFINE_SPINLOCK(list_lock);
+
+static void update_irq(struct mdp_kms *mdp_kms)
+{
+        struct mdp_irq *irq;
+        uint32_t irqmask = mdp_kms->vblank_mask;
+
+        BUG_ON(!spin_is_locked(&list_lock));
+
+        list_for_each_entry(irq, &mdp_kms->irq_list, node)
+                irqmask |= irq->irqmask;
+
+        mdp_kms->funcs->set_irqmask(mdp_kms, irqmask);
+}
+
+static void update_irq_unlocked(struct mdp_kms *mdp_kms)
+{
+        unsigned long flags;
+        spin_lock_irqsave(&list_lock, flags);
+        update_irq(mdp_kms);
+        spin_unlock_irqrestore(&list_lock, flags);
+}
+
+void mdp_dispatch_irqs(struct mdp_kms *mdp_kms, uint32_t status)
+{
+        struct mdp_irq *handler, *n;
+        unsigned long flags;
+
+        spin_lock_irqsave(&list_lock, flags);
+        mdp_kms->in_irq = true;
+        list_for_each_entry_safe(handler, n, &mdp_kms->irq_list, node) {
+                if (handler->irqmask & status) {
+                        spin_unlock_irqrestore(&list_lock, flags);
+                        handler->irq(handler, handler->irqmask & status);
+                        spin_lock_irqsave(&list_lock, flags);
+                }
+        }
+        mdp_kms->in_irq = false;
+        update_irq(mdp_kms);
+        spin_unlock_irqrestore(&list_lock, flags);
+
+}
+
+void mdp_update_vblank_mask(struct mdp_kms *mdp_kms, uint32_t mask, bool enable)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&list_lock, flags);
+        if (enable)
+                mdp_kms->vblank_mask |= mask;
+        else
+                mdp_kms->vblank_mask &= ~mask;
+        update_irq(mdp_kms);
+        spin_unlock_irqrestore(&list_lock, flags);
+}
+
+static void wait_irq(struct mdp_irq *irq, uint32_t irqstatus)
+{
+        struct mdp_irq_wait *wait =
+                        container_of(irq, struct mdp_irq_wait, irq);
+        wait->count--;
+        wake_up_all(&wait_event);
+}
+
+void mdp_irq_wait(struct mdp_kms *mdp_kms, uint32_t irqmask)
+{
+        struct mdp_irq_wait wait = {
+                .irq = {
+                        .irq = wait_irq,
+                        .irqmask = irqmask,
+                },
+                .count = 1,
+        };
+        mdp_irq_register(mdp_kms, &wait.irq);
+        wait_event(wait_event, (wait.count <= 0));
+        mdp_irq_unregister(mdp_kms, &wait.irq);
+}
+
+void mdp_irq_register(struct mdp_kms *mdp_kms, struct mdp_irq *irq)
+{
+        unsigned long flags;
+        bool needs_update = false;
+
+        spin_lock_irqsave(&list_lock, flags);
+
+        if (!irq->registered) {
+                irq->registered = true;
+                list_add(&irq->node, &mdp_kms->irq_list);
+                needs_update = !mdp_kms->in_irq;
+        }
+
+        spin_unlock_irqrestore(&list_lock, flags);
+
+        if (needs_update)
+                update_irq_unlocked(mdp_kms);
+}
+
+void mdp_irq_unregister(struct mdp_kms *mdp_kms, struct mdp_irq *irq)
+{
+        unsigned long flags;
+        bool needs_update = false;
+
+        spin_lock_irqsave(&list_lock, flags);
+
+        if (irq->registered) {
+                irq->registered = false;
+                list_del(&irq->node);
+                needs_update = !mdp_kms->in_irq;
+        }
+
+        spin_unlock_irqrestore(&list_lock, flags);
+
+        if (needs_update)
+                update_irq_unlocked(mdp_kms);
+}
diff --git a/drivers/gpu/drm/msm/mdp/mdp_kms.h b/drivers/gpu/drm/msm/mdp/mdp_kms.h
index 710edf7e19d1..99557b5ad4fd 100644
--- a/drivers/gpu/drm/msm/mdp/mdp_kms.h
+++ b/drivers/gpu/drm/msm/mdp/mdp_kms.h
@@ -23,8 +23,64 @@
 #include <linux/regulator/consumer.h>
 
 #include "msm_drv.h"
+#include "msm_kms.h"
 #include "mdp_common.xml.h"
 
+struct mdp_kms;
+
+struct mdp_kms_funcs {
+        struct msm_kms_funcs base;
+        void (*set_irqmask)(struct mdp_kms *mdp_kms, uint32_t irqmask);
+};
+
+struct mdp_kms {
+        struct msm_kms base;
+
+        const struct mdp_kms_funcs *funcs;
+
+        /* irq handling: */
+        bool in_irq;
+        struct list_head irq_list;    /* list of mdp4_irq */
+        uint32_t vblank_mask;         /* irq bits set for userspace vblank */
+};
+#define to_mdp_kms(x) container_of(x, struct mdp_kms, base)
+
+static inline void mdp_kms_init(struct mdp_kms *mdp_kms,
+                const struct mdp_kms_funcs *funcs)
+{
+        mdp_kms->funcs = funcs;
+        INIT_LIST_HEAD(&mdp_kms->irq_list);
+        msm_kms_init(&mdp_kms->base, &funcs->base);
+}
+
+/*
+ * irq helpers:
+ */
+
+/* For transiently registering for different MDP irqs that various parts
+ * of the KMS code need during setup/configuration.  These are not
+ * necessarily the same as what drm_vblank_get/put() are requesting, and
+ * the hysteresis in drm_vblank_put() is not necessarily desirable for
+ * internal housekeeping related irq usage.
+ */
+struct mdp_irq {
+        struct list_head node;
+        uint32_t irqmask;
+        bool registered;
+        void (*irq)(struct mdp_irq *irq, uint32_t irqstatus);
+};
+
+void mdp_dispatch_irqs(struct mdp_kms *mdp_kms, uint32_t status);
+void mdp_update_vblank_mask(struct mdp_kms *mdp_kms, uint32_t mask, bool enable);
+void mdp_irq_wait(struct mdp_kms *mdp_kms, uint32_t irqmask);
+void mdp_irq_register(struct mdp_kms *mdp_kms, struct mdp_irq *irq);
+void mdp_irq_unregister(struct mdp_kms *mdp_kms, struct mdp_irq *irq);
+
+
+/*
+ * pixel format helpers:
+ */
+
 struct mdp_format {
         struct msm_format base;
         enum mdp_bpc bpc_r, bpc_g, bpc_b;
@@ -35,7 +91,6 @@ struct mdp_format {
 };
 #define to_mdp_format(x) container_of(x, struct mdp_format, base)
 
-
 uint32_t mdp_get_formats(uint32_t *formats, uint32_t max_formats);
 const struct msm_format *mdp_get_format(struct msm_kms *kms, uint32_t format);
 
diff --git a/drivers/gpu/drm/msm/msm_kms.h b/drivers/gpu/drm/msm/msm_kms.h
index f01e239f7261..dc0d30f5b291 100644
--- a/drivers/gpu/drm/msm/msm_kms.h
+++ b/drivers/gpu/drm/msm/msm_kms.h
@@ -49,8 +49,19 @@ struct msm_kms_funcs {
 
 struct msm_kms {
         const struct msm_kms_funcs *funcs;
+
+        /* irq handling: */
+        bool in_irq;
+        struct list_head irq_list;    /* list of mdp4_irq */
+        uint32_t vblank_mask;         /* irq bits set for userspace vblank */
 };
 
+static inline void msm_kms_init(struct msm_kms *kms,
+                const struct msm_kms_funcs *funcs)
+{
+        kms->funcs = funcs;
+}
+
 struct msm_kms *mdp4_kms_init(struct drm_device *dev);
 
 #endif /* __MSM_KMS_H__ */