irqchip/mvebu-gicp: Clear pending interrupts on init

When a kexec'ed kernel boots up, there might be stale unhandled interrupts
pending in the interrupt controller. These are delivered as spurious
interrupts once the boot CPU enables interrupts.

Clear all pending interrupts when the driver is initialized to prevent
these spurious interrupts from locking the CPU in an endless loop.

Signed-off-by: Elad Nachman <enachman@marvell.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250803102548.669682-2-enachman@marvell.com

diff --git a/drivers/irqchip/irq-mvebu-gicp.c b/drivers/irqchip/irq-mvebu-gicp.c
index d3232d6d8dced54502f3a5a2c90a2e24110f4990..fd85c845e0151fed18d5185937118ba25e239af7 100644 (file)
--- a/drivers/irqchip/irq-mvebu-gicp.c
+++ b/drivers/irqchip/irq-mvebu-gicp.c
@@ -177,6 +177,7 @@ static int mvebu_gicp_probe(struct platform_device *pdev)
                .ops    = &gicp_domain_ops,
        };
        struct mvebu_gicp *gicp;
+       void __iomem *base;
        int ret, i;
 
        gicp = devm_kzalloc(&pdev->dev, sizeof(*gicp), GFP_KERNEL);
@@ -236,6 +237,15 @@ static int mvebu_gicp_probe(struct platform_device *pdev)
                return -ENODEV;
        }
 
+       base = ioremap(gicp->res->start, gicp->res->end - gicp->res->start);
+       if (IS_ERR(base)) {
+               dev_err(&pdev->dev, "ioremap() failed. Unable to clear pending interrupts.\n");
+       } else {
+               for (i = 0; i < 64; i++)
+                       writel(i, base + GICP_CLRSPI_NSR_OFFSET);
+               iounmap(base);
+       }
+
        return msi_create_parent_irq_domain(&info, &gicp_msi_parent_ops) ? 0 : -ENOMEM;
 }