[PATCH] irqchip/versatile-fpga: Apply clear-mask earlier

Sungbo Eo
2020-03-21T13:40:40Z

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@gorani.run>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Daniel Golle <daniel@makrotopia.org>
---
drivers/irqchip/irq-versatile-fpga.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/irqchip/irq-versatile-fpga.c b/drivers/irqchip/irq-versatile-fpga.c
index 70e2cfff8175..f1386733d3bc 100644
--- a/drivers/irqchip/irq-versatile-fpga.c
+++ b/drivers/irqchip/irq-versatile-fpga.c
@@ -212,6 +212,9 @@ int __init fpga_irq_of_init(struct device_node *node,
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) {
@@ -221,9 +224,6 @@ int __init fpga_irq_of_init(struct device_node *node,

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
--
2.25.2