From: Sungbo Eo <mans0n@xxxxxxxxxx> commit 6a214a28132f19ace3d835a6d8f6422ec80ad200 upstream. Clear its own IRQs before the parent IRQ get enabled, so that the remaining IRQs do not accidentally interrupt the parent IRQ controller. This patch also fixes a reboot bug on OX820 SoC, where the remaining rps-timer IRQ raises a GIC interrupt that is left pending. After that, the rps-timer IRQ is cleared during driver initialization, and there's no IRQ left in rps-irq when local_irq_enable() is called, which evokes an error message "unexpected IRQ trap". Fixes: bdd272cbb97a ("irqchip: versatile FPGA: support cascaded interrupts from DT") Signed-off-by: Sungbo Eo <mans0n@xxxxxxxxxx> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Link: https://lore.kernel.org/r/20200321133842.2408823-1-mans0n@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/irqchip/irq-versatile-fpga.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/irqchip/irq-versatile-fpga.c +++ b/drivers/irqchip/irq-versatile-fpga.c @@ -211,6 +211,9 @@ int __init fpga_irq_of_init(struct devic if (of_property_read_u32(node, "valid-mask", &valid_mask)) valid_mask = 0; + writel(clear_mask, base + IRQ_ENABLE_CLEAR); + writel(clear_mask, base + FIQ_ENABLE_CLEAR); + /* Some chips are cascaded from a parent IRQ */ parent_irq = irq_of_parse_and_map(node, 0); if (!parent_irq) { @@ -220,9 +223,6 @@ int __init fpga_irq_of_init(struct devic fpga_irq_init(base, node->name, 0, parent_irq, valid_mask, node); - writel(clear_mask, base + IRQ_ENABLE_CLEAR); - writel(clear_mask, base + FIQ_ENABLE_CLEAR); - /* * On Versatile AB/PB, some secondary interrupts have a direct * pass-thru to the primary controller for IRQs 20 and 22-31 which need