From 740955399f42caa6406761975656b8aa5b88a39c Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.com>
Date: Thu, 25 Nov 2021 14:46:55 +0000
Subject: [PATCH] drm/vc4: Move HDMI reset to pm_resume

Pi0-3 have power domains attached to the pm_runtime hooks
for the HDMI block. Initialisation done in the reset called
from bind is therefore lost if all users of the domain are
suspended.
The VEC shares the same lowest level clock/power gating as
the HDMI block, so whilst that is enabled the block is never
actually powered down, but if it isn't enabled then we lose
the state.

Reset and initialise the HDMI block from pm_resume.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c      | 61 ++++++++++++++++++-----------
 drivers/gpu/drm/vc4/vc4_hdmi_regs.h |  4 +-
 2 files changed, 41 insertions(+), 24 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -2194,7 +2194,6 @@ static int vc4_hdmi_cec_init(struct vc4_
 	struct platform_device *pdev = vc4_hdmi->pdev;
 	struct device *dev = &pdev->dev;
 	unsigned long flags;
-	u32 value;
 	int ret;
 
 	if (!of_find_property(dev->of_node, "interrupts", NULL)) {
@@ -2214,15 +2213,6 @@ static int vc4_hdmi_cec_init(struct vc4_
 	cec_fill_conn_info_from_drm(&conn_info, &vc4_hdmi->connector);
 	cec_s_conn_info(vc4_hdmi->cec_adap, &conn_info);
 
-	spin_lock_irqsave(&vc4_hdmi->hw_lock, flags);
-	value = HDMI_READ(HDMI_CEC_CNTRL_1);
-	/* Set the logical address to Unregistered */
-	value |= VC4_HDMI_CEC_ADDR_MASK;
-	HDMI_WRITE(HDMI_CEC_CNTRL_1, value);
-	spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags);
-
-	vc4_hdmi_cec_update_clk_div(vc4_hdmi);
-
 	if (vc4_hdmi->variant->external_irq_controller) {
 		ret = request_threaded_irq(platform_get_irq_byname(pdev, "cec-rx"),
 					   vc4_cec_irq_handler_rx_bare,
@@ -2285,6 +2275,29 @@ static void vc4_hdmi_cec_exit(struct vc4
 
 	cec_unregister_adapter(vc4_hdmi->cec_adap);
 }
+
+static int vc4_hdmi_cec_resume(struct vc4_hdmi *vc4_hdmi)
+{
+	unsigned long flags;
+	u32 value;
+
+	spin_lock_irqsave(&vc4_hdmi->hw_lock, flags);
+	value = HDMI_READ(HDMI_CEC_CNTRL_1);
+	/* Set the logical address to Unregistered */
+	value |= VC4_HDMI_CEC_ADDR_MASK;
+	HDMI_WRITE(HDMI_CEC_CNTRL_1, value);
+	spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags);
+
+	vc4_hdmi_cec_update_clk_div(vc4_hdmi);
+
+	if (!vc4_hdmi->variant->external_irq_controller) {
+		spin_lock_irqsave(&vc4_hdmi->hw_lock, flags);
+		HDMI_WRITE(HDMI_CEC_CPU_MASK_SET, 0xffffffff);
+		spin_unlock_irqrestore(&vc4_hdmi->hw_lock, flags);
+	}
+
+	return 0;
+}
 #else
 static int vc4_hdmi_cec_init(struct vc4_hdmi *vc4_hdmi)
 {
@@ -2293,6 +2306,10 @@ static int vc4_hdmi_cec_init(struct vc4_
 
 static void vc4_hdmi_cec_exit(struct vc4_hdmi *vc4_hdmi) {};
 
+static void vc4_hdmi_cec_resume(struct vc4_hdmi *vc4_hdmi)
+{
+	return 0;
+}
 #endif
 
 static int vc4_hdmi_build_regset(struct vc4_hdmi *vc4_hdmi,
@@ -2527,6 +2544,15 @@ static int vc4_hdmi_runtime_resume(struc
 	if (ret)
 		return ret;
 
+	if (vc4_hdmi->variant->reset)
+		vc4_hdmi->variant->reset(vc4_hdmi);
+
+	ret = vc4_hdmi_cec_resume(vc4_hdmi);
+	if (ret) {
+		clk_disable_unprepare(vc4_hdmi->hsm_clock);
+		return ret;
+	}
+
 	return 0;
 }
 
--- a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h
@@ -417,7 +417,7 @@ static inline u32 vc4_hdmi_read(struct v
 	const struct vc4_hdmi_variant *variant = hdmi->variant;
 	void __iomem *base;
 
-	WARN_ON(!pm_runtime_active(&hdmi->pdev->dev));
+	WARN_ON(pm_runtime_status_suspended(&hdmi->pdev->dev));
 
 	if (reg >= variant->num_registers) {
 		dev_warn(&hdmi->pdev->dev,
@@ -447,7 +447,7 @@ static inline void vc4_hdmi_write(struct
 
 	lockdep_assert_held(&hdmi->hw_lock);
 
-	WARN_ON(!pm_runtime_active(&hdmi->pdev->dev));
+	WARN_ON(pm_runtime_status_suspended(&hdmi->pdev->dev));
 
 	if (reg >= variant->num_registers) {
 		dev_warn(&hdmi->pdev->dev,
