IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);

#define IRQCHIP_DECLARE(name,compstr,fn) \ static const struct of_device_id irqchip_of_match_##name \ __used __section(__irqchip_of_table) \ = { .compatible = compstr, .data = fn }

static int __init gic_of_init(struct device_node *node, struct device_node *parent){- dist_base = of_iomap(node, 0); //映射GICD的寄存器地址空间 reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK; if (reg != GIC_PIDR2_ARCH_GICv3 && reg != GIC_PIDR2_ARCH_GICv4) { pr_err("%s: no distributor detected, giving up\n", node->full_name); err = -ENODEV; goto out_unmap_dist; } if (of_property_read_u32(node, "#redistributor-regions", &redist_regions))//通过 DTS 读取 redistributor-regions 的值。 redist_regions = 1; redist_base = kzalloc(sizeof(*redist_base) * redist_regions, GFP_KERNEL); if (!redist_base) { err = -ENOMEM; goto out_unmap_dist; } for (i = 0; i < redist_regions; i++) {//为一个 GICR 域分配基地址 redist_base[i] = of_iomap(node, 1 + i); if (!redist_base[i]) { pr_err("%s: couldn't map region %d\n", node->full_name, i); err = -ENODEV; goto out_unmap_rdist; } } if (of_property_read_u64(node, "redistributor-stride", &redist_stride)) redist_stride = 0;// GIC 初始化流程，执行完成后，GIC 中断控制器即可正常工作：外部外设中断、软件中断（SGI）会被正确分发到指定 CPU，并触发你注册的中断处理逻辑。 set_handle_irq(gic_handle_irq);/将GIC 中断处理的顶层入口函数 gic_handle_irq 注册到系统的中断向量表中 gic_smp_init();/初始化多核（SMP）环境下的 GIC 中断路由与同步机制，让中断能够被正确分发到指定的 CPU 核心 gic_dist_init();/初始化 GIC 分发器（GICD，Distributor），这是 GIC 的 “全局中枢” gic_cpu_init();/初始化当前执行该函数的 CPU 核心对应的 GIC CPU 接口（GICC，CPU Interface） return 0;