Merge tag 'irq-urgent-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:
 "A series of fixes for the Renesas RZG21 interrupt chip driver to
  prevent spurious and misrouted interrupts.

   - Ensure that posted writes are flushed in the eoi() callback

   - Ensure that interrupts are masked at the chip level when the
     trigger type is changed

   - Clear the interrupt status register when setting up edge type
     trigger modes

   - Ensure that the trigger type and routing information is set before
     the interrupt is enabled"

* tag 'irq-urgent-2024-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/renesas-rzg2l: Do not set TIEN and TINT source at the same time
  irqchip/renesas-rzg2l: Prevent spurious interrupts when setting trigger type
  irqchip/renesas-rzg2l: Rename rzg2l_irq_eoi()
  irqchip/renesas-rzg2l: Rename rzg2l_tint_eoi()
  irqchip/renesas-rzg2l: Flush posted write in irq_eoi()

drivers/irqchip/irq-renesas-rzg2l.c

@@ -85,10 +85,9 @@ static struct rzg2l_irqc_priv *irq_data_to_priv(struct irq_data *data)
 	return data->domain->host_data;
 }
 
-static void rzg2l_irq_eoi(struct irq_data *d)
+static void rzg2l_clear_irq_int(struct rzg2l_irqc_priv *priv, unsigned int hwirq)
 {
-	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
-	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+	unsigned int hw_irq = hwirq - IRQC_IRQ_START;
 	u32 bit = BIT(hw_irq);
 	u32 iitsr, iscr;
 
@@ -99,20 +98,30 @@ static void rzg2l_irq_eoi(struct irq_data *d)
 	 * ISCR can only be cleared if the type is falling-edge, rising-edge or
 	 * falling/rising-edge.
 	 */
-	if ((iscr & bit) && (iitsr & IITSR_IITSEL_MASK(hw_irq)))
+	if ((iscr & bit) && (iitsr & IITSR_IITSEL_MASK(hw_irq))) {
 		writel_relaxed(iscr & ~bit, priv->base + ISCR);
+		/*
+		 * Enforce that the posted write is flushed to prevent that the
+		 * just handled interrupt is raised again.
+		 */
+		readl_relaxed(priv->base + ISCR);
+	}
 }
 
-static void rzg2l_tint_eoi(struct irq_data *d)
+static void rzg2l_clear_tint_int(struct rzg2l_irqc_priv *priv, unsigned int hwirq)
 {
-	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_TINT_START;
-	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
-	u32 bit = BIT(hw_irq);
+	u32 bit = BIT(hwirq - IRQC_TINT_START);
 	u32 reg;
 
 	reg = readl_relaxed(priv->base + TSCR);
-	if (reg & bit)
+	if (reg & bit) {
 		writel_relaxed(reg & ~bit, priv->base + TSCR);
+		/*
+		 * Enforce that the posted write is flushed to prevent that the
+		 * just handled interrupt is raised again.
+		 */
+		readl_relaxed(priv->base + TSCR);
+	}
 }
 
 static void rzg2l_irqc_eoi(struct irq_data *d)
@@ -122,9 +131,9 @@ static void rzg2l_irqc_eoi(struct irq_data *d)
 
 	raw_spin_lock(&priv->lock);
 	if (hw_irq >= IRQC_IRQ_START && hw_irq <= IRQC_IRQ_COUNT)
-		rzg2l_irq_eoi(d);
+		rzg2l_clear_irq_int(priv, hw_irq);
 	else if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ)
-		rzg2l_tint_eoi(d);
+		rzg2l_clear_tint_int(priv, hw_irq);
 	raw_spin_unlock(&priv->lock);
 	irq_chip_eoi_parent(d);
 }
@@ -142,7 +151,7 @@ static void rzg2l_irqc_irq_disable(struct irq_data *d)
 
 		raw_spin_lock(&priv->lock);
 		reg = readl_relaxed(priv->base + TSSR(tssr_index));
-		reg &= ~(TSSEL_MASK << TSSEL_SHIFT(tssr_offset));
+		reg &= ~(TIEN << TSSEL_SHIFT(tssr_offset));
 		writel_relaxed(reg, priv->base + TSSR(tssr_index));
 		raw_spin_unlock(&priv->lock);
 	}
@@ -154,7 +163,6 @@ static void rzg2l_irqc_irq_enable(struct irq_data *d)
 	unsigned int hw_irq = irqd_to_hwirq(d);
 
 	if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
-		unsigned long tint = (uintptr_t)irq_data_get_irq_chip_data(d);
 		struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
 		u32 offset = hw_irq - IRQC_TINT_START;
 		u32 tssr_offset = TSSR_OFFSET(offset);
@@ -163,7 +171,7 @@ static void rzg2l_irqc_irq_enable(struct irq_data *d)
 
 		raw_spin_lock(&priv->lock);
 		reg = readl_relaxed(priv->base + TSSR(tssr_index));
-		reg |= (TIEN | tint) << TSSEL_SHIFT(tssr_offset);
+		reg |= TIEN << TSSEL_SHIFT(tssr_offset);
 		writel_relaxed(reg, priv->base + TSSR(tssr_index));
 		raw_spin_unlock(&priv->lock);
 	}
@@ -172,8 +180,10 @@ static void rzg2l_irqc_irq_enable(struct irq_data *d)
 
 static int rzg2l_irq_set_type(struct irq_data *d, unsigned int type)
 {
-	unsigned int hw_irq = irqd_to_hwirq(d) - IRQC_IRQ_START;
 	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
+	unsigned int hwirq = irqd_to_hwirq(d);
+	u32 iitseln = hwirq - IRQC_IRQ_START;
+	bool clear_irq_int = false;
 	u16 sense, tmp;
 
 	switch (type & IRQ_TYPE_SENSE_MASK) {
@@ -183,14 +193,17 @@ static int rzg2l_irq_set_type(struct irq_data *d, unsigned int type)
 
 	case IRQ_TYPE_EDGE_FALLING:
 		sense = IITSR_IITSEL_EDGE_FALLING;
+		clear_irq_int = true;
 		break;
 
 	case IRQ_TYPE_EDGE_RISING:
 		sense = IITSR_IITSEL_EDGE_RISING;
+		clear_irq_int = true;
 		break;
 
 	case IRQ_TYPE_EDGE_BOTH:
 		sense = IITSR_IITSEL_EDGE_BOTH;
+		clear_irq_int = true;
 		break;
 
 	default:
@@ -199,21 +212,40 @@ static int rzg2l_irq_set_type(struct irq_data *d, unsigned int type)
 
 	raw_spin_lock(&priv->lock);
 	tmp = readl_relaxed(priv->base + IITSR);
-	tmp &= ~IITSR_IITSEL_MASK(hw_irq);
-	tmp |= IITSR_IITSEL(hw_irq, sense);
+	tmp &= ~IITSR_IITSEL_MASK(iitseln);
+	tmp |= IITSR_IITSEL(iitseln, sense);
+	if (clear_irq_int)
+		rzg2l_clear_irq_int(priv, hwirq);
 	writel_relaxed(tmp, priv->base + IITSR);
 	raw_spin_unlock(&priv->lock);
 
 	return 0;
 }
 
+static u32 rzg2l_disable_tint_and_set_tint_source(struct irq_data *d, struct rzg2l_irqc_priv *priv,
+						  u32 reg, u32 tssr_offset, u8 tssr_index)
+{
+	u32 tint = (u32)(uintptr_t)irq_data_get_irq_chip_data(d);
+	u32 tien = reg & (TIEN << TSSEL_SHIFT(tssr_offset));
+
+	/* Clear the relevant byte in reg */
+	reg &= ~(TSSEL_MASK << TSSEL_SHIFT(tssr_offset));
+	/* Set TINT and leave TIEN clear */
+	reg |= tint << TSSEL_SHIFT(tssr_offset);
+	writel_relaxed(reg, priv->base + TSSR(tssr_index));
+
+	return reg | tien;
+}
+
 static int rzg2l_tint_set_edge(struct irq_data *d, unsigned int type)
 {
 	struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
 	unsigned int hwirq = irqd_to_hwirq(d);
 	u32 titseln = hwirq - IRQC_TINT_START;
+	u32 tssr_offset = TSSR_OFFSET(titseln);
+	u8 tssr_index = TSSR_INDEX(titseln);
 	u8 index, sense;
-	u32 reg;
+	u32 reg, tssr;
 
 	switch (type & IRQ_TYPE_SENSE_MASK) {
 	case IRQ_TYPE_EDGE_RISING:
@@ -235,10 +267,14 @@ static int rzg2l_tint_set_edge(struct irq_data *d, unsigned int type)
 	}
 
 	raw_spin_lock(&priv->lock);
+	tssr = readl_relaxed(priv->base + TSSR(tssr_index));
+	tssr = rzg2l_disable_tint_and_set_tint_source(d, priv, tssr, tssr_offset, tssr_index);
 	reg = readl_relaxed(priv->base + TITSR(index));
 	reg &= ~(IRQ_MASK << (titseln * TITSEL_WIDTH));
 	reg |= sense << (titseln * TITSEL_WIDTH);
 	writel_relaxed(reg, priv->base + TITSR(index));
+	rzg2l_clear_tint_int(priv, hwirq);
+	writel_relaxed(tssr, priv->base + TSSR(tssr_index));
 	raw_spin_unlock(&priv->lock);
 
 	return 0;