On Wed, Jan 10, 2024 at 1:10 PM Yu Chien Peter Lin <peterlin@xxxxxxxxxxxxx> wrote: > > Currently, the implementation of the RISC-V INTC driver uses the > interrupt cause as the hardware interrupt number, with a maximum of > 64 interrupts. However, the platform can expand the interrupt number > further for custom local interrupts. > > To fully utilize the available local interrupt sources, switch > to using irq_domain_create_tree() that creates the radix tree > map, add global variables (riscv_intc_nr_irqs, riscv_intc_custom_base > and riscv_intc_custom_nr_irqs) to determine the valid range of local > interrupt number (hwirq). > > Signed-off-by: Yu Chien Peter Lin <peterlin@xxxxxxxxxxxxx> > Reviewed-by: Randolph <randolph@xxxxxxxxxxxxx> Looks good to me. Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx> Regards, Anup > --- > Changes v1 -> v2: > - Fixed irq mapping failure checking (suggested by Clément and Anup) > Changes v2 -> v3: > - No change > Changes v3 -> v4: (Suggested by Thomas [1]) > - Use pr_warn_ratelimited instead > - Fix coding style and commit message > Changes v4 -> v5: (Suggested by Thomas) > - Fix commit message > Changes v5 -> v6: (Suggested by Anup [2]) > - Add riscv_intc_* global variables for checking range in riscv_intc_domain_alloc() > - Advertise the number of interrupts allowed > Changes v6 -> v7: > - No functional change > > [1] https://patchwork.kernel.org/project/linux-riscv/patch/20231023004100.2663486-3-peterlin@xxxxxxxxxxxxx/#25573085 > [2] https://patchwork.kernel.org/project/linux-riscv/patch/20231213070301.1684751-3-peterlin@xxxxxxxxxxxxx/#25636589 > --- > drivers/irqchip/irq-riscv-intc.c | 30 +++++++++++++++++++++++------- > 1 file changed, 23 insertions(+), 7 deletions(-) > > diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c > index e8d01b14ccdd..b13a16b164c9 100644 > --- a/drivers/irqchip/irq-riscv-intc.c > +++ b/drivers/irqchip/irq-riscv-intc.c > @@ -19,15 +19,17 @@ > #include <linux/smp.h> > > static struct irq_domain *intc_domain; > +static unsigned int riscv_intc_nr_irqs __ro_after_init; > +static unsigned int riscv_intc_custom_base __ro_after_init; > +static unsigned int riscv_intc_custom_nr_irqs __ro_after_init; > > static asmlinkage void riscv_intc_irq(struct pt_regs *regs) > { > unsigned long cause = regs->cause & ~CAUSE_IRQ_FLAG; > > - if (unlikely(cause >= BITS_PER_LONG)) > - panic("unexpected interrupt cause"); > - > - generic_handle_domain_irq(intc_domain, cause); > + if (generic_handle_domain_irq(intc_domain, cause)) > + pr_warn_ratelimited("Failed to handle interrupt (cause: %ld)\n", > + cause); > } > > /* > @@ -93,6 +95,14 @@ static int riscv_intc_domain_alloc(struct irq_domain *domain, > if (ret) > return ret; > > + /* > + * Only allow hwirq for which we have corresponding standard or > + * custom interrupt enable register. > + */ > + if ((riscv_intc_nr_irqs <= hwirq && hwirq < riscv_intc_custom_base) || > + (riscv_intc_custom_base + riscv_intc_custom_nr_irqs) <= hwirq) > + return -EINVAL; > + > for (i = 0; i < nr_irqs; i++) { > ret = riscv_intc_domain_map(domain, virq + i, hwirq + i); > if (ret) > @@ -117,8 +127,7 @@ static int __init riscv_intc_init_common(struct fwnode_handle *fn) > { > int rc; > > - intc_domain = irq_domain_create_linear(fn, BITS_PER_LONG, > - &riscv_intc_domain_ops, NULL); > + intc_domain = irq_domain_create_tree(fn, &riscv_intc_domain_ops, NULL); > if (!intc_domain) { > pr_err("unable to add IRQ domain\n"); > return -ENXIO; > @@ -132,7 +141,10 @@ static int __init riscv_intc_init_common(struct fwnode_handle *fn) > > riscv_set_intc_hwnode_fn(riscv_intc_hwnode); > > - pr_info("%d local interrupts mapped\n", BITS_PER_LONG); > + pr_info("%d local interrupts mapped\n", riscv_intc_nr_irqs); > + if (riscv_intc_custom_nr_irqs) > + pr_info("%d custom local interrupts mapped\n", > + riscv_intc_custom_nr_irqs); > > return 0; > } > @@ -166,6 +178,10 @@ static int __init riscv_intc_init(struct device_node *node, > return 0; > } > > + riscv_intc_nr_irqs = BITS_PER_LONG; > + riscv_intc_custom_base = riscv_intc_nr_irqs; > + riscv_intc_custom_nr_irqs = 0; > + > return riscv_intc_init_common(of_node_to_fwnode(node)); > } > > -- > 2.34.1 >
