openwrt/target/linux/mediatek/patches-5.10/610-pcie-mediatek-fix-clearing-interrupt-status.patch

From: Felix Fietkau <nbd@nbd.name>
Date: Fri, 4 Sep 2020 18:33:27 +0200
Subject: [PATCH] pcie-mediatek: fix clearing interrupt status

Clearing the status needs to happen after running the handler, otherwise
we will get an extra spurious interrupt after the cause has been cleared

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---

--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -615,10 +615,10 @@ static void mtk_pcie_intr_handler(struct
 	if (status & INTX_MASK) {
 		for_each_set_bit_from(bit, &status, PCI_NUM_INTX + INTX_SHIFT) {
 			/* Clear the INTx */
-			writel(1 << bit, port->base + PCIE_INT_STATUS);
 			virq = irq_find_mapping(port->irq_domain,
 						bit - INTX_SHIFT);
 			generic_handle_irq(virq);
+			writel(1 << bit, port->base + PCIE_INT_STATUS);
 		}
 	}