drm/msm: fix fallout of atomic dpms changes

As a result of atomic DPMS support, the various prepare/commit hooks get
called in a way that msm dislikes.  We were expecting prepare/commit to
bracket a modeset, which is no longer the case.  This was needed to hold
various extra clk's (such as interface clks) on while we are touching
registers, and in the case of mdp4 holding vblank enabled.

The most straightforward way to deal with this, since we already have
our own atomic_commit(), is to just handle prepare/commit internally to
the driver (with some additional vfuncs for mdp4 vs mdp5), and switch
everything over to instead use the new enable/disable hooks.  It doesn't
really change too much, despite the code motion.  What used to be in the
encoder/crtc dpms() fxns is split out into enable/disable.

We should be able to drop our own enable-state tracking, as the atomic
helpers should do this for us.  But keeping that for the short term for
extra debugging as atomic stablizes.

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

3 files changed, 85 insertions, 79 deletions

diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c
index 47f101d2f9fa..7416cae60479 100644
--- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c
+++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_crtc.c
@@ -138,28 +138,6 @@ static void mdp5_crtc_destroy(struct drm_crtc *crtc)
 	kfree(mdp5_crtc);
 }
 
-static void mdp5_crtc_dpms(struct drm_crtc *crtc, int mode)
-{
-	struct mdp5_crtc *mdp5_crtc = to_mdp5_crtc(crtc);
-	struct mdp5_kms *mdp5_kms = get_kms(crtc);
-	bool enabled = (mode == DRM_MODE_DPMS_ON);
-
-	DBG("%s: mode=%d", mdp5_crtc->name, mode);
-
-	if (enabled != mdp5_crtc->enabled) {
-		if (enabled) {
-			mdp5_enable(mdp5_kms);
-			mdp_irq_register(&mdp5_kms->base, &mdp5_crtc->err);
-		} else {
-			/* set STAGE_UNUSED for all layers */
-			mdp5_ctl_blend(mdp5_crtc->ctl, mdp5_crtc->lm, 0x00000000);
-			mdp_irq_unregister(&mdp5_kms->base, &mdp5_crtc->err);
-			mdp5_disable(mdp5_kms);
-		}
-		mdp5_crtc->enabled = enabled;
-	}
-}
-
 static bool mdp5_crtc_mode_fixup(struct drm_crtc *crtc,
 		const struct drm_display_mode *mode,
 		struct drm_display_mode *adjusted_mode)
@@ -256,23 +234,41 @@ static void mdp5_crtc_mode_set_nofb(struct drm_crtc *crtc)
 	spin_unlock_irqrestore(&mdp5_crtc->lm_lock, flags);
 }
 
-static void mdp5_crtc_prepare(struct drm_crtc *crtc)
+static void mdp5_crtc_disable(struct drm_crtc *crtc)
 {
 	struct mdp5_crtc *mdp5_crtc = to_mdp5_crtc(crtc);
+	struct mdp5_kms *mdp5_kms = get_kms(crtc);
+
 	DBG("%s", mdp5_crtc->name);
-	/* make sure we hold a ref to mdp clks while setting up mode: */
-	mdp5_enable(get_kms(crtc));
-	mdp5_crtc_dpms(crtc, DRM_MODE_DPMS_OFF);
+
+	if (WARN_ON(!mdp5_crtc->enabled))
+		return;
+
+	/* set STAGE_UNUSED for all layers */
+	mdp5_ctl_blend(mdp5_crtc->ctl, mdp5_crtc->lm, 0x00000000);
+
+	mdp_irq_unregister(&mdp5_kms->base, &mdp5_crtc->err);
+	mdp5_disable(mdp5_kms);
+
+	mdp5_crtc->enabled = false;
 }
 
-static void mdp5_crtc_commit(struct drm_crtc *crtc)
+static void mdp5_crtc_enable(struct drm_crtc *crtc)
 {
 	struct mdp5_crtc *mdp5_crtc = to_mdp5_crtc(crtc);
+	struct mdp5_kms *mdp5_kms = get_kms(crtc);
+
 	DBG("%s", mdp5_crtc->name);
-	mdp5_crtc_dpms(crtc, DRM_MODE_DPMS_ON);
+
+	if (WARN_ON(mdp5_crtc->enabled))
+		return;
+
+	mdp5_enable(mdp5_kms);
+	mdp_irq_register(&mdp5_kms->base, &mdp5_crtc->err);
+
 	crtc_flush_all(crtc);
-	/* drop the ref to mdp clk's that we got in prepare: */
-	mdp5_disable(get_kms(crtc));
+
+	mdp5_crtc->enabled = true;
 }
 
 struct plane_state {
@@ -391,11 +387,10 @@ static const struct drm_crtc_funcs mdp5_crtc_funcs = {
 };
 
 static const struct drm_crtc_helper_funcs mdp5_crtc_helper_funcs = {
-	.dpms = mdp5_crtc_dpms,
 	.mode_fixup = mdp5_crtc_mode_fixup,
 	.mode_set_nofb = mdp5_crtc_mode_set_nofb,
-	.prepare = mdp5_crtc_prepare,
-	.commit = mdp5_crtc_commit,
+	.prepare = mdp5_crtc_disable,
+	.commit = mdp5_crtc_enable,
 	.atomic_check = mdp5_crtc_atomic_check,
 	.atomic_begin = mdp5_crtc_atomic_begin,
 	.atomic_flush = mdp5_crtc_atomic_flush,
diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c
index 0254bfdeb92f..b5494315345d 100644
--- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c
+++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_encoder.c
@@ -110,45 +110,6 @@ static const struct drm_encoder_funcs mdp5_encoder_funcs = {
 	.destroy = mdp5_encoder_destroy,
 };
 
-static void mdp5_encoder_dpms(struct drm_encoder *encoder, int mode)
-{
-	struct mdp5_encoder *mdp5_encoder = to_mdp5_encoder(encoder);
-	struct mdp5_kms *mdp5_kms = get_kms(encoder);
-	int intf = mdp5_encoder->intf;
-	bool enabled = (mode == DRM_MODE_DPMS_ON);
-	unsigned long flags;
-
-	DBG("mode=%d", mode);
-
-	if (enabled == mdp5_encoder->enabled)
-		return;
-
-	if (enabled) {
-		bs_set(mdp5_encoder, 1);
-		spin_lock_irqsave(&mdp5_encoder->intf_lock, flags);
-		mdp5_write(mdp5_kms, REG_MDP5_INTF_TIMING_ENGINE_EN(intf), 1);
-		spin_unlock_irqrestore(&mdp5_encoder->intf_lock, flags);
-	} else {
-		spin_lock_irqsave(&mdp5_encoder->intf_lock, flags);
-		mdp5_write(mdp5_kms, REG_MDP5_INTF_TIMING_ENGINE_EN(intf), 0);
-		spin_unlock_irqrestore(&mdp5_encoder->intf_lock, flags);
-
-		/*
-		 * Wait for a vsync so we know the ENABLE=0 latched before
-		 * the (connector) source of the vsync's gets disabled,
-		 * otherwise we end up in a funny state if we re-enable
-		 * before the disable latches, which results that some of
-		 * the settings changes for the new modeset (like new
-		 * scanout buffer) don't latch properly..
-		 */
-		mdp_irq_wait(&mdp5_kms->base, intf2vblank(intf));
-
-		bs_set(mdp5_encoder, 0);
-	}
-
-	mdp5_encoder->enabled = enabled;
-}
-
 static bool mdp5_encoder_mode_fixup(struct drm_encoder *encoder,
 		const struct drm_display_mode *mode,
 		struct drm_display_mode *adjusted_mode)
@@ -225,25 +186,61 @@ static void mdp5_encoder_mode_set(struct drm_encoder *encoder,
 	spin_unlock_irqrestore(&mdp5_encoder->intf_lock, flags);
 }
 
-static void mdp5_encoder_prepare(struct drm_encoder *encoder)
+static void mdp5_encoder_disable(struct drm_encoder *encoder)
 {
-	mdp5_encoder_dpms(encoder, DRM_MODE_DPMS_OFF);
+	struct mdp5_encoder *mdp5_encoder = to_mdp5_encoder(encoder);
+	struct mdp5_kms *mdp5_kms = get_kms(encoder);
+	int intf = mdp5_encoder->intf;
+	unsigned long flags;
+
+	if (WARN_ON(!mdp5_encoder->enabled))
+		return;
+
+	spin_lock_irqsave(&mdp5_encoder->intf_lock, flags);
+	mdp5_write(mdp5_kms, REG_MDP5_INTF_TIMING_ENGINE_EN(intf), 0);
+	spin_unlock_irqrestore(&mdp5_encoder->intf_lock, flags);
+
+	/*
+	 * Wait for a vsync so we know the ENABLE=0 latched before
+	 * the (connector) source of the vsync's gets disabled,
+	 * otherwise we end up in a funny state if we re-enable
+	 * before the disable latches, which results that some of
+	 * the settings changes for the new modeset (like new
+	 * scanout buffer) don't latch properly..
+	 */
+	mdp_irq_wait(&mdp5_kms->base, intf2vblank(intf));
+
+	bs_set(mdp5_encoder, 0);
+
+	mdp5_encoder->enabled = false;
 }
 
-static void mdp5_encoder_commit(struct drm_encoder *encoder)
+static void mdp5_encoder_enable(struct drm_encoder *encoder)
 {
 	struct mdp5_encoder *mdp5_encoder = to_mdp5_encoder(encoder);
+	struct mdp5_kms *mdp5_kms = get_kms(encoder);
+	int intf = mdp5_encoder->intf;
+	unsigned long flags;
+
+	if (WARN_ON(mdp5_encoder->enabled))
+		return;
+
 	mdp5_crtc_set_intf(encoder->crtc, mdp5_encoder->intf,
 			mdp5_encoder->intf_id);
-	mdp5_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
+
+	bs_set(mdp5_encoder, 1);
+	spin_lock_irqsave(&mdp5_encoder->intf_lock, flags);
+	mdp5_write(mdp5_kms, REG_MDP5_INTF_TIMING_ENGINE_EN(intf), 1);
+	spin_unlock_irqrestore(&mdp5_encoder->intf_lock, flags);
+
+	mdp5_encoder->enabled = false;
 }
 
 static const struct drm_encoder_helper_funcs mdp5_encoder_helper_funcs = {
-	.dpms = mdp5_encoder_dpms,
 	.mode_fixup = mdp5_encoder_mode_fixup,
 	.mode_set = mdp5_encoder_mode_set,
-	.prepare = mdp5_encoder_prepare,
-	.commit = mdp5_encoder_commit,
+	.prepare = mdp5_encoder_disable,
+	.commit = mdp5_encoder_enable,
 };
 
 /* initialize encoder */
diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
index 9f01a4f21af2..e13e102372f5 100644
--- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
+++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
@@ -68,6 +68,18 @@ static int mdp5_hw_init(struct msm_kms *kms)
 	return 0;
 }
 
+static void mdp5_prepare_commit(struct msm_kms *kms, struct drm_atomic_state *state)
+{
+	struct mdp5_kms *mdp5_kms = to_mdp5_kms(to_mdp_kms(kms));
+	mdp5_enable(mdp5_kms);
+}
+
+static void mdp5_complete_commit(struct msm_kms *kms, struct drm_atomic_state *state)
+{
+	struct mdp5_kms *mdp5_kms = to_mdp5_kms(to_mdp_kms(kms));
+	mdp5_disable(mdp5_kms);
+}
+
 static long mdp5_round_pixclk(struct msm_kms *kms, unsigned long rate,
 		struct drm_encoder *encoder)
 {
@@ -115,6 +127,8 @@ static const struct mdp_kms_funcs kms_funcs = {
 		.irq             = mdp5_irq,
 		.enable_vblank   = mdp5_enable_vblank,
 		.disable_vblank  = mdp5_disable_vblank,
+		.prepare_commit  = mdp5_prepare_commit,
+		.complete_commit = mdp5_complete_commit,
 		.get_format      = mdp_get_format,
 		.round_pixclk    = mdp5_round_pixclk,
 		.preclose        = mdp5_preclose,