From: Guo Ren <[email protected]> For PLIC, we only have enable registers to control per hart's irq affinity and irq_set_affinity would call plic_irq_toggle to enable the IRQ's routing. So we can't enable irq in irq_domain_map before request_irq, it'll let uninitialized devices' irq exception.
The solution is to check the irq has been enabled, just like what irq-gic-v3 has done in gic_set_affinity. Signed-off-by: Guo Ren <[email protected]> --- drivers/irqchip/irq-sifive-plic.c | 45 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 42 insertions(+), 3 deletions(-) diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index 0003322..1a63859 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -130,6 +130,36 @@ static void plic_irq_mask(struct irq_data *d) } #ifdef CONFIG_SMP +static inline bool plic_toggle_is_enabled(struct plic_handler *handler, + int hwirq) +{ + u32 __iomem *reg = handler->enable_base + (hwirq / 32) * sizeof(u32); + u32 hwirq_mask = 1 << (hwirq % 32); + + if (readl(reg) & hwirq_mask) + return true; + else + return false; +} + +static inline bool plic_irq_is_enabled(const struct cpumask *mask, + struct irq_data *d) +{ + int cpu; + + for_each_cpu(cpu, mask) { + struct plic_handler *handler = per_cpu_ptr(&plic_handlers, cpu); + + if (!handler->present) + continue; + + if (plic_toggle_is_enabled(handler, d->hwirq)) + return true; + } + + return false; +} + static int plic_set_affinity(struct irq_data *d, const struct cpumask *mask_val, bool force) { @@ -141,8 +171,10 @@ static int plic_set_affinity(struct irq_data *d, irq_data_update_effective_affinity(d, &amask); - plic_irq_toggle(&priv->lmask, d, 0); - plic_irq_toggle(&amask, d, 1); + if (plic_irq_is_enabled(&priv->lmask, d)) { + plic_irq_toggle(&priv->lmask, d, 0); + plic_irq_toggle(&amask, d, 1); + } return IRQ_SET_MASK_OK_DONE; } @@ -168,12 +200,19 @@ static struct irq_chip plic_chip = { static int plic_irqdomain_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hwirq) { + unsigned int cpu; struct plic_priv *priv = d->host_data; irq_domain_set_info(d, irq, hwirq, &plic_chip, d->host_data, handle_fasteoi_irq, NULL, NULL); irq_set_noprobe(irq); - irq_set_affinity(irq, &priv->lmask); + + cpu = cpumask_any_and(&priv->lmask, cpu_online_mask); + if (WARN_ON_ONCE(cpu >= nr_cpu_ids)) + return -EINVAL; + + irq_set_affinity(irq, cpumask_of(cpu)); + return 0; } -- 2.7.4
