VIC domain 与 gpio domain 的硬件拓扑图描述

以下是 s3c6410a 的 irq domain 描述,着重凸显了 gpio irq domain
以下 每个颜色 是一个irq domain ,共 8个irq domain

linux cascaded irq domain

• irq domain & 级联(cascaded)irq domain

// 仅用作示例
// gpio domain 注册的用于 vic 调用的handler
if (parent_irq) {                                                            
	irq_set_chained_handler(parent_irq, gpio_handle_irq_cascaded, v);
}  

• 非级联的中断发生流程

一旦发生硬件中断，经过CPU architecture相关的中断代码之后，会调用irq handler，该函数的一般过程如下：

（1）首先找到root interrupt controller对应的irq domain。

（2）根据HW 寄存器信息和irq domain信息获取HW interrupt ID

（3）调用irq_find_mapping找到HW interrupt ID对应的irq number

（4）调用handle_IRQ（对于ARM平台）来处理该irq number

• 级联中断发生流程

按照当前 gpio 级联到 vic
假设 vic0 是 A, GPN0-3的domain 是 B
假设 GPN0 发生了中断

A.1首先找到root interrupt controller(在这里是vic)对应的irq domain
A.2根据VIC HW 寄存器信息和irq domain信息获取HW interrupt ID  // VIC0的 0
A.3调用irq_find_mapping找到HW interrupt ID(在这里是0)对应的irq number
A.4调用irq domain B 注册 的 handler( irq_set_chained_handler 设定的gpio_handle_irq_cascaded)

B.1gpio_handle_irq_cascaded找到gpio对应的irq domain // 和 A.1 中的irq domain完全不同
B.2根据GPIO HW 寄存器信息和irq domain信息获取HW interrupt ID // 和 A.2 中的HW interrupt ID完全不同
B.3调用irq_find_mapping找到HW interrupt ID对应的irq number // 和 A.3 中的 irq number 完全不同
B.4调用 驱动 注册 的 handler( request_irq 设定的) // 这个驱动对应的设备用到了 GPN0

linux irq domain 实例

irq: Added domain :soc:interrupt-controller@71200000
irq: Added domain :soc:interrupt-controller@71300000
irq: Added domain :soc:pinctrl@7f008000:gpa
irq: Added domain :soc:pinctrl@7f008000:gpb
irq: Added domain :soc:pinctrl@7f008000:gpc
irq: Added domain :soc:pinctrl@7f008000:gpd
irq: Added domain :soc:pinctrl@7f008000:gpf
irq: Added domain :soc:pinctrl@7f008000:gpg
irq: Added domain :soc:pinctrl@7f008000:gph
irq: Added domain :soc:pinctrl@7f008000:gpo
irq: Added domain :soc:pinctrl@7f008000:gpp
irq: Added domain :soc:pinctrl@7f008000:gpq
irq: Added domain :soc:pinctrl@7f008000:gpl
irq: Added domain :soc:pinctrl@7f008000:gpm
irq: Added domain :soc:pinctrl@7f008000:gpn

irq: Added domain :soc:pinctrl@7f008000:gpn
irq: -> using domain @c0889d80
SUD File: kernel/irq/irqdomain.c, Line: 00557: irq_domain_associate,domain:c0889d80,virq:33,hwirq:7
SUD File: kernel/irq/irqdomain.c, Line: 00559: irq_domain_associate,c024afa8 // s3c64xx_eint0_irq_map domain->ops->map
SUD File: kernel/irq/irqdomain.c, Line: 00499: irq_domain_set_mapping,7,16
irq: irq 7 on domain gpn mapped to virtual irq 33

s3c64xx_eint_eint0_init
	for (i = 0; i < NUM_EINT0_IRQ; ++i) { // 设置 parent 相关的irq
		irq = irq_of_parse_and_map(eint0_np, i);
		irq_set_chained_handler_and_data(irq, s3c64xx_eint0_handlers[i], data);
	}

	for (i = 0; i < d->nr_banks; ++i, ++bank) {
		bank->irq_domain = irq_domain_add_linear(bank->of_node, nr_eints, &s3c64xx_eint0_irqd_ops, ddata);
	}

使用domain 映射号码
	irq_create_mapping

VIC domain 与 gpio domain 的硬件拓扑语言描述

VIC 与 INT_EINTx 的关系

Int. No.	Sources	Description	Group
53	INT_EINT4	External interrupt Group 1 ~ Group 9	VIC1
33	INT_EINT3	External interrupt Group 0 20 ~ 27	VIC1
32	INT_EINT2	External interrupt Group 0 12 ~ 19	VIC1
1	INT_EINT1	External interrupt Group 0 4 ~ 11	VIC0
0	INT_EINT0	External interrupt Group 0 0 ~ 3	VIC0

INT_EINTx 与 GPIO的关系

INT_EINT0

External interrupt Group 0  0 - 15  <===> GPN0-GPN15
	GPN0-3			: 0
	GPN4-11			: 1
	GPN12-15 & GPL8-GPL11 : 32
External interrupt Group 0  16 - 22 <===> GPL8-GPL14
	GPL12-GPL14 & GPM0-GPM4 : 33
External interrupt Group 0  23 - 27 <===> GPM0-GPM4

INT_EINT1

External interrupt Group 0  0 - 15  <===> GPN0-GPN15
External interrupt Group 0  16 - 22 <===> GPL8-GPL14
External interrupt Group 0  23 - 27 <===> GPM0-GPM4

INT_EINT2

External interrupt Group 0  0 - 15  <===> GPN0-GPN15
External interrupt Group 0  16 - 22 <===> GPL8-GPL14
External interrupt Group 0  23 - 27 <===> GPM0-GPM4

INT_EINT3

External interrupt Group 0  0 - 15  <===> GPN0-GPN15
External interrupt Group 0  16 - 22 <===> GPL8-GPL14
External interrupt Group 0  23 - 27 <===> GPM0-GPM4

INT_EINT4

INT_EINT4 与 External interrupt Group1-9 的关系

External interrupt Group1

EINT1 0 - 7   <===> GPA 0 - 7
EINT1 8 - 14  <===> GPB 0 - 6

External interrupt Group2

EINT2 0 - 7   <===> GPC 0 - 7

External interrupt Group3

EINT3 0 - 4   <===> GPD 0 - 4

External interrupt Group4

EINT4 0 - 13   <===> GPF 0 - 13

External interrupt Group5

EINT5 0 - 6   <===> GPG 0 - 6

External interrupt Group6

EINT6 0 - 9   <===> GPH 0 - 9

External interrupt Group7

EINT7 0 - 15   <===> GPO 0 - 7

External interrupt Group8

EINT8 0 - 14   <===> GPP 0 - 7

External interrupt Group9

EINT9 0 - 8   <===> GPQ 0 - 8