[PATCH v4 5/8] PCI: armada8k: support AC5 INTx PCIe interrupts

[Elad Nachman <enachman@marvell.com>]

From: Elad Nachman <enachman@marvell.com>

Support message emulation of INTx PCIe interrupts for Marvell AC5/X.
These message emulations require writing an additional status register
with acknowledge bits.

Signed-off-by: Elad Nachman <enachman@marvell.com>
---
v4:
   Split the part not handling INTx interrupts to a separate patch

 drivers/pci/controller/dwc/pcie-armada8k.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-armada8k.c b/drivers/pci/controller/dwc/pcie-armada8k.c
index 02481ecadd25..2b94e32853ad 100644
--- a/drivers/pci/controller/dwc/pcie-armada8k.c
+++ b/drivers/pci/controller/dwc/pcie-armada8k.c
@@ -61,6 +61,7 @@ struct armada8k_pcie_of_data {
 
 #define PCIE_GLOBAL_INT_CAUSE1_REG	(PCIE_VENDOR_REGS_OFFSET + 0x1C)
 #define PCIE_GLOBAL_INT_MASK1_REG	(PCIE_VENDOR_REGS_OFFSET + 0x20)
+#define PCIE_GLOBAL_INT_CAUSE2_REG	(PCIE_VENDOR_REGS_OFFSET + 0x24)
 #define PCIE_GLOBAL_INT_MASK2_REG	(PCIE_VENDOR_REGS_OFFSET + 0x28)
 #define PCIE_INT_A_ASSERT_MASK		BIT(9)
 #define PCIE_INT_B_ASSERT_MASK		BIT(10)
@@ -267,8 +268,14 @@ static irqreturn_t armada8k_pcie_irq_handler(int irq, void *arg)
 	 */
 	val = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_INT_CAUSE1_REG);
 	dw_pcie_writel_dbi(pci, PCIE_GLOBAL_INT_CAUSE1_REG, val);
-	if ((PCIE_MSI_MASK_AC5 & val) && (pcie->pcie_type == ARMADA8K_PCIE_TYPE_AC5))
-		dw_handle_msi_irq(&pci->pp);
+	if (pcie->pcie_type == ARMADA8K_PCIE_TYPE_AC5) {
+		if (PCIE_MSI_MASK_AC5 & val)
+			dw_handle_msi_irq(&pci->pp);
+
+		val = dw_pcie_readl_dbi(pci, PCIE_GLOBAL_INT_CAUSE2_REG);
+		/* Now clear the second interrupt cause. */
+		dw_pcie_writel_dbi(pci, PCIE_GLOBAL_INT_CAUSE2_REG, val);
+	}
 
 	return IRQ_HANDLED;
 }
-- 
2.17.1