drm/msm/dpu: add helper to get IRQ-related data

In preparation to reworking IRQ indices, move irq_tbl access to
a separate helper.
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/550931/
Link: https://lore.kernel.org/r/20230802100426.4184892-5-dmitry.baryshkov@linaro.org

drivers/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c

@@ -206,6 +206,12 @@ static inline bool dpu_core_irq_is_valid(struct dpu_hw_intr *intr,
 	return irq_idx >= 0 && irq_idx < intr->total_irqs;
 }
 
+static inline struct dpu_hw_intr_entry *dpu_core_irq_get_entry(struct dpu_hw_intr *intr,
+							       int irq_idx)
+{
+	return &intr->irq_tbl[irq_idx];
+}
+
 /**
  * dpu_core_irq_callback_handler - dispatch core interrupts
  * @dpu_kms:		Pointer to DPU's KMS structure
@@ -213,17 +219,19 @@ static inline bool dpu_core_irq_is_valid(struct dpu_hw_intr *intr,
  */
 static void dpu_core_irq_callback_handler(struct dpu_kms *dpu_kms, int irq_idx)
 {
+	struct dpu_hw_intr_entry *irq_entry = dpu_core_irq_get_entry(dpu_kms->hw_intr, irq_idx);
+
 	VERB("irq_idx=%d\n", irq_idx);
 
-	if (!dpu_kms->hw_intr->irq_tbl[irq_idx].cb)
+	if (!irq_entry->cb)
 		DRM_ERROR("no registered cb, idx:%d\n", irq_idx);
 
-	atomic_inc(&dpu_kms->hw_intr->irq_tbl[irq_idx].count);
+	atomic_inc(&irq_entry->count);
 
 	/*
 	 * Perform registered function callback
 	 */
-	dpu_kms->hw_intr->irq_tbl[irq_idx].cb(dpu_kms->hw_intr->irq_tbl[irq_idx].arg);
+	irq_entry->cb(irq_entry->arg);
 }
 
 irqreturn_t dpu_core_irq(struct msm_kms *kms)
@@ -510,6 +518,7 @@ int dpu_core_irq_register_callback(struct dpu_kms *dpu_kms, int irq_idx,
 		void (*irq_cb)(void *arg),
 		void *irq_arg)
 {
+	struct dpu_hw_intr_entry *irq_entry;
 	unsigned long irq_flags;
 	int ret;
 
@@ -527,15 +536,16 @@ int dpu_core_irq_register_callback(struct dpu_kms *dpu_kms, int irq_idx,
 
 	spin_lock_irqsave(&dpu_kms->hw_intr->irq_lock, irq_flags);
 
-	if (unlikely(WARN_ON(dpu_kms->hw_intr->irq_tbl[irq_idx].cb))) {
+	irq_entry = dpu_core_irq_get_entry(dpu_kms->hw_intr, irq_idx);
+	if (unlikely(WARN_ON(irq_entry->cb))) {
 		spin_unlock_irqrestore(&dpu_kms->hw_intr->irq_lock, irq_flags);
 
 		return -EBUSY;
 	}
 
 	trace_dpu_core_irq_register_callback(irq_idx, irq_cb);
-	dpu_kms->hw_intr->irq_tbl[irq_idx].arg = irq_arg;
-	dpu_kms->hw_intr->irq_tbl[irq_idx].cb = irq_cb;
+	irq_entry->arg = irq_arg;
+	irq_entry->cb = irq_cb;
 
 	ret = dpu_hw_intr_enable_irq_locked(
 				dpu_kms->hw_intr,
@@ -552,6 +562,7 @@ int dpu_core_irq_register_callback(struct dpu_kms *dpu_kms, int irq_idx,
 
 int dpu_core_irq_unregister_callback(struct dpu_kms *dpu_kms, int irq_idx)
 {
+	struct dpu_hw_intr_entry *irq_entry;
 	unsigned long irq_flags;
 	int ret;
 
@@ -570,8 +581,9 @@ int dpu_core_irq_unregister_callback(struct dpu_kms *dpu_kms, int irq_idx)
 		DPU_ERROR("Fail to disable IRQ for irq_idx:%d: %d\n",
 					irq_idx, ret);
 
-	dpu_kms->hw_intr->irq_tbl[irq_idx].cb = NULL;
-	dpu_kms->hw_intr->irq_tbl[irq_idx].arg = NULL;
+	irq_entry = dpu_core_irq_get_entry(dpu_kms->hw_intr, irq_idx);
+	irq_entry->cb = NULL;
+	irq_entry->arg = NULL;
 
 	spin_unlock_irqrestore(&dpu_kms->hw_intr->irq_lock, irq_flags);
 
@@ -584,14 +596,16 @@ int dpu_core_irq_unregister_callback(struct dpu_kms *dpu_kms, int irq_idx)
 static int dpu_debugfs_core_irq_show(struct seq_file *s, void *v)
 {
 	struct dpu_kms *dpu_kms = s->private;
+	struct dpu_hw_intr_entry *irq_entry;
 	unsigned long irq_flags;
 	int i, irq_count;
 	void *cb;
 
 	for (i = 0; i < dpu_kms->hw_intr->total_irqs; i++) {
 		spin_lock_irqsave(&dpu_kms->hw_intr->irq_lock, irq_flags);
-		irq_count = atomic_read(&dpu_kms->hw_intr->irq_tbl[i].count);
-		cb = dpu_kms->hw_intr->irq_tbl[i].cb;
+		irq_entry = dpu_core_irq_get_entry(dpu_kms->hw_intr, i);
+		irq_count = atomic_read(&irq_entry->count);
+		cb = irq_entry->cb;
 		spin_unlock_irqrestore(&dpu_kms->hw_intr->irq_lock, irq_flags);
 
 		if (irq_count || cb)
@@ -614,6 +628,7 @@ void dpu_debugfs_core_irq_init(struct dpu_kms *dpu_kms,
 void dpu_core_irq_preinstall(struct msm_kms *kms)
 {
 	struct dpu_kms *dpu_kms = to_dpu_kms(kms);
+	struct dpu_hw_intr_entry *irq_entry;
 	int i;
 
 	pm_runtime_get_sync(&dpu_kms->pdev->dev);
@@ -621,22 +636,27 @@ void dpu_core_irq_preinstall(struct msm_kms *kms)
 	dpu_disable_all_irqs(dpu_kms);
 	pm_runtime_put_sync(&dpu_kms->pdev->dev);
 
-	for (i = 0; i < dpu_kms->hw_intr->total_irqs; i++)
-		atomic_set(&dpu_kms->hw_intr->irq_tbl[i].count, 0);
+	for (i = 0; i < dpu_kms->hw_intr->total_irqs; i++) {
+		irq_entry = dpu_core_irq_get_entry(dpu_kms->hw_intr, i);
+		atomic_set(&irq_entry->count, 0);
+	}
 }
 
 void dpu_core_irq_uninstall(struct msm_kms *kms)
 {
 	struct dpu_kms *dpu_kms = to_dpu_kms(kms);
+	struct dpu_hw_intr_entry *irq_entry;
 	int i;
 
 	if (!dpu_kms->hw_intr)
 		return;
 
 	pm_runtime_get_sync(&dpu_kms->pdev->dev);
-	for (i = 0; i < dpu_kms->hw_intr->total_irqs; i++)
-		if (dpu_kms->hw_intr->irq_tbl[i].cb)
+	for (i = 0; i < dpu_kms->hw_intr->total_irqs; i++) {
+		irq_entry = dpu_core_irq_get_entry(dpu_kms->hw_intr, i);
+		if (irq_entry->cb)
 			DPU_ERROR("irq_idx=%d still enabled/registered\n", i);
+	}
 
 	dpu_clear_irqs(dpu_kms);
 	dpu_disable_all_irqs(dpu_kms);

drivers/gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.h

@@ -38,6 +38,12 @@ enum dpu_hw_intr_reg {
 
 #define DPU_IRQ_IDX(reg_idx, offset)	(reg_idx * 32 + offset)
 
+struct dpu_hw_intr_entry {
+	void (*cb)(void *arg);
+	void *arg;
+	atomic_t count;
+};
+
 /**
  * struct dpu_hw_intr: hw interrupts handling data structure
  * @hw:               virtual address mapping
@@ -57,11 +63,7 @@ struct dpu_hw_intr {
 	unsigned long irq_mask;
 	const struct dpu_intr_reg *intr_set;
 
-	struct {
-		void (*cb)(void *arg);
-		void *arg;
-		atomic_t count;
-	} irq_tbl[];
+	struct dpu_hw_intr_entry irq_tbl[];
 };
 
 /**