From: Christoph Hellwig hch@lst.de
[ Upstream commit 9ce06497c2722a0f9109e4cc3ce35b7a69617886 ]
When running in M-mode, the S-mode plic handlers are still listed in the device tree. Ignore them by setting the maximum threshold.
Signed-off-by: Christoph Hellwig hch@lst.de Acked-by: Marc Zyngier maz@kernel.org Signed-off-by: Paul Walmsley paul.walmsley@sifive.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/irqchip/irq-sifive-plic.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index cf755964f2f8b..c72c036aea768 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -244,6 +244,7 @@ static int __init plic_init(struct device_node *node, struct plic_handler *handler; irq_hw_number_t hwirq; int cpu, hartid; + u32 threshold = 0;
if (of_irq_parse_one(node, i, &parent)) { pr_err("failed to parse parent for context %d.\n", i); @@ -266,10 +267,16 @@ static int __init plic_init(struct device_node *node, continue; }
+ /* + * When running in M-mode we need to ignore the S-mode handler. + * Here we assume it always comes later, but that might be a + * little fragile. + */ handler = per_cpu_ptr(&plic_handlers, cpu); if (handler->present) { pr_warn("handler already present for context %d.\n", i); - continue; + threshold = 0xffffffff; + goto done; }
handler->present = true; @@ -279,8 +286,9 @@ static int __init plic_init(struct device_node *node, handler->enable_base = plic_regs + ENABLE_BASE + i * ENABLE_PER_HART;
+done: /* priority must be > threshold to trigger an interrupt */ - writel(0, handler->hart_base + CONTEXT_THRESHOLD); + writel(threshold, handler->hart_base + CONTEXT_THRESHOLD); for (hwirq = 1; hwirq <= nr_irqs; hwirq++) plic_toggle(handler, hwirq, 0); nr_handlers++;