From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Mon, 30 Jul 2018 11:52:34 +0100
Subject: drm/armada: push responsibility for clock management to backend
Git-commit: a0fbb35ecde52aa5abf5975d117d29e3b30f7b91
Patch-mainline: v4.19-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

Push responsibility for managing the clock during DPMS down into the
variant backend, rather than the CRTC layer having knowledge of its
state.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/armada/armada_510.c  |   19 +++++++++++++++++++
 drivers/gpu/drm/armada/armada_crtc.c |   19 ++++++-------------
 drivers/gpu/drm/armada/armada_drm.h  |    2 ++
 3 files changed, 27 insertions(+), 13 deletions(-)

--- a/drivers/gpu/drm/armada/armada_510.c
+++ b/drivers/gpu/drm/armada/armada_510.c
@@ -79,8 +79,27 @@ static int armada510_crtc_compute_clock(
 	return 0;
 }
 
+static void armada510_crtc_disable(struct armada_crtc *dcrtc)
+{
+	if (!IS_ERR(dcrtc->clk)) {
+		clk_disable_unprepare(dcrtc->clk);
+		dcrtc->clk = ERR_PTR(-EINVAL);
+	}
+}
+
+static void armada510_crtc_enable(struct armada_crtc *dcrtc,
+	const struct drm_display_mode *mode)
+{
+	if (IS_ERR(dcrtc->clk)) {
+		dcrtc->clk = dcrtc->extclk[0];
+		WARN_ON(clk_prepare_enable(dcrtc->clk));
+	}
+}
+
 const struct armada_variant armada510_ops = {
 	.has_spu_adv_reg = true,
 	.init = armada510_crtc_init,
 	.compute_clock = armada510_crtc_compute_clock,
+	.disable = armada510_crtc_disable,
+	.enable = armada510_crtc_enable,
 };
--- a/drivers/gpu/drm/armada/armada_crtc.c
+++ b/drivers/gpu/drm/armada/armada_crtc.c
@@ -253,14 +253,14 @@ static void armada_drm_crtc_dpms(struct
 	if (dpms_blanked(dcrtc->dpms) != dpms_blanked(dpms)) {
 		if (dpms_blanked(dpms))
 			armada_drm_vblank_off(dcrtc);
-		else if (!IS_ERR(dcrtc->clk))
-			WARN_ON(clk_prepare_enable(dcrtc->clk));
+		else if (dcrtc->variant->enable)
+			dcrtc->variant->enable(dcrtc, &crtc->hwmode);
 		dcrtc->dpms = dpms;
 		armada_drm_crtc_update(dcrtc);
 		if (!dpms_blanked(dpms))
 			drm_crtc_vblank_on(&dcrtc->crtc);
-		else if (!IS_ERR(dcrtc->clk))
-			clk_disable_unprepare(dcrtc->clk);
+		else if (dcrtc->variant->disable)
+			dcrtc->variant->disable(dcrtc);
 	} else if (dcrtc->dpms != dpms) {
 		dcrtc->dpms = dpms;
 	}
@@ -462,13 +462,6 @@ static void armada_drm_crtc_mode_set_nof
 		      adj->type, adj->flags);
 	DRM_DEBUG_KMS("lm %d rm %d tm %d bm %d\n", lm, rm, tm, bm);
 
-	/*
-	 * If we are blanked, we would have disabled the clock.  Re-enable
-	 * it so that compute_clock() does the right thing.
-	 */
-	if (!IS_ERR(dcrtc->clk) && dpms_blanked(dcrtc->dpms))
-		WARN_ON(clk_prepare_enable(dcrtc->clk));
-
 	/* Now compute the divider for real */
 	dcrtc->variant->compute_clock(dcrtc, adj, &sclk);
 
@@ -824,8 +817,8 @@ static void armada_drm_crtc_destroy(stru
 	priv->dcrtc[dcrtc->num] = NULL;
 	drm_crtc_cleanup(&dcrtc->crtc);
 
-	if (!IS_ERR(dcrtc->clk))
-		clk_disable_unprepare(dcrtc->clk);
+	if (dcrtc->variant->disable)
+		dcrtc->variant->disable(dcrtc);
 
 	writel_relaxed(0, dcrtc->base + LCD_SPU_IRQ_ENA);
 
--- a/drivers/gpu/drm/armada/armada_drm.h
+++ b/drivers/gpu/drm/armada/armada_drm.h
@@ -46,6 +46,8 @@ struct armada_variant {
 	int (*compute_clock)(struct armada_crtc *,
 			     const struct drm_display_mode *,
 			     uint32_t *);
+	void (*disable)(struct armada_crtc *);
+	void (*enable)(struct armada_crtc *, const struct drm_display_mode *);
 };
 
 /* Variant ops */