diff --git a/IMX6ULL/doc_pic/08_Interrupt/15_链式中断控制器驱动程序编写.md b/IMX6ULL/doc_pic/08_Interrupt/15_链式中断控制器驱动程序编写.md index a2d8e49..eaff2b2 100644 --- a/IMX6ULL/doc_pic/08_Interrupt/15_链式中断控制器驱动程序编写.md +++ b/IMX6ULL/doc_pic/08_Interrupt/15_链式中断控制器驱动程序编写.md @@ -15,7 +15,6 @@ * `Linux-5.4\drivers\irqchip\irq-stm32-exti.c` * `Linux-5.4\arch\arm\boot\dts\stm32mp151.dtsi` - * 本节视频源码在GIT仓库里 ```shell @@ -91,13 +90,15 @@ ### 2. 硬件模型 - 内核中有各类中断控制器的驱动程序，它们涉及的硬件过于复杂，从这些杂乱的代码中去讲清楚中断体系，比较难。 +下图中列出了链式中断控制器、层级中断控制器，本节课程只涉及左边的链式中断控制器。 - 我们实现一些虚拟的中断控制器，如下图所示。 +内核中有各类中断控制器的驱动程序，它们涉及的硬件过于复杂，从这些杂乱的代码中去讲清楚中断体系，比较难。 - 实际板子中，我们可以通过按键触发中断。 +我们实现一些虚拟的中断控制器，如下图所示。 - 对于这些虚拟的中断控制器，我们没有真实按键，通过devmem指令写GIC的PENDING寄存器触发中断。 +实际板子中，我们可以通过按键触发中断。 + +对于这些虚拟的中断控制器，我们没有真实按键，通过devmem指令写GIC的PENDING寄存器触发中断。 ![image-20210703133953035](pic/08_Interrupt/076_virtual_intc_hardware.png) diff --git a/IMX6ULL/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.md b/IMX6ULL/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.md new file mode 100644 index 0000000..7d96ea4 --- /dev/null +++ b/IMX6ULL/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.md @@ -0,0 +1,283 @@ +## legacy方式代码的上机实验 + +参考资料： + +* [linux kernel的中断子系统之（七）：GIC代码分析](http://www.wowotech.net/irq_subsystem/gic_driver.html) + +* Linux 4.9.88内核源码 + + * `Linux-4.9.88\drivers\gpio\gpio-mxc.c` + * `Linux-4.9.88\arch\arm\boot\dts\imx6ull.dtsi` + +* Linux 5.4内核源码 + + * `Linux-5.4\drivers\pinctrl\stm32\pinctrl-stm32mp157.c` + * `Linux-5.4\drivers\irqchip\irq-stm32-exti.c` + * `Linux-5.4\arch\arm\boot\dts\stm32mp151.dtsi` + +* 芯片手册 + + * IMX6ULL: imx6ullrm.pdf + * STM32MP157: DM00327659.pdf + +* 本节视频源码在GIT仓库里 + + ```shell + doc_and_source_for_drivers\ + IMX6ULL\source\08_Interrupt\ + 04_virtual_int_controller_legacy_ok + + doc_and_source_for_drivers\ + STM32MP157\source\A7\08_Interrupt\ + 04_virtual_int_controller_legacy_ok + ``` + + + +### 1. 确定中断号n + +![](pic/08_Interrupt/076_virtual_intc_hardware.png) + +查看芯片手册，选择一个保留的、未使用的GIC SPI中断即可。 + +#### 1.1 IMX6ULL + +看芯片手册第3章： + +![image-20210704072332512](pic/08_Interrupt/077_imx6ll_reserved_gic_int.png) + +看上图，选择122号中断，它是SPI里的122号中断，GIC里的编号是(32+122)=154。 + + + +#### 1.2 STM32MP157 + +看芯片手册第21.2节： + +![image-20210704072802087](pic/08_Interrupt/078_stm32mp157_reserved_gic_int.png) + +看上图，选择210号中断，它是SPI里的210号中断，GIC里的编号是(32+210)=242。 + +### 2. 怎么触发中断 + +可以通过devmem命令直接写GIC的PENDING寄存区。 + +![image-20210704073305082](pic/08_Interrupt/079_GICD_ISPENDRn.png) + +GICD_ISPENDRn有多个寄存器，每个寄存器中每一位对应一个GIC中断，写入1就可以触发该中断。 + +写哪一个GICD_ISPENDRn寄存器？写哪一位？使用下列公式来确定： + +![image-20210704073518013](pic/08_Interrupt/080_GICD_ISPENDRn_calc.png) + +查看内核设备树文件imx6ull.dtsi、stm32mp151.dtsi，可以知道： + +* IMX6ULL的GIC Distributor 地址是：0x00a01000 + ![image-20210704103943340](pic/08_Interrupt/082_imx6ull_gic_dts.png) +* STM32MP157的GIC Distributor 地址是：0xa0021000 + ![image-20210704074850302](pic/08_Interrupt/081_stm32mp157_gic_dts.png) + +| 芯片 | SPI中断号 | GIC中断号 | n,bit | GICD_ISPENDRn地址 | 命令 | +| ---------- | --------- | --------- | ----- | ----------------- | ---------------------------- | +| IMX6LLL | 122 | 154 | 4,26 | 0xa01210 | devmem 0xa01210 32 0x4000000 | +| STM32MP157 | 210 | 242 | 7,18 | 0xa002121c | devmem 0xa002121c 32 0x40000 | + + + +### 3. 上机实验 + +#### 3.1 设置工具链 + +##### 1. STM32MP157 + + ```shell + export ARCH=arm + export CROSS_COMPILE=arm-buildroot-linux-gnueabihf- + export PATH=$PATH:/home/book/100ask_stm32mp157_pro-sdk/ToolChain/arm-buildroot-linux-gnueabihf_sdk-buildroot/bin + ``` + +##### 2. IMX6ULL + + ```shell + export ARCH=arm + export CROSS_COMPILE=arm-linux-gnueabihf- + export PATH=$PATH:/home/book/100ask_imx6ull-sdk/ToolChain/gcc-linaro-6.2.1-2016.11-x86_64_arm-linux-gnueabihf/bin + ``` + + + +#### 3.2 编译、替换设备树 + +##### 1. STM32MP157 + + * 修改`arch/arm/boot/dts/stm32mp157c-100ask-512d-lcd-v1.dts`，添加如下代码： + + ```shell + / { + virtual_intc: virtual_intc_100ask { + compatible = "100ask,virtual_intc"; + + interrupt-controller; + #interrupt-cells = <2>; + + interrupt-parent = <&intc>; + interrupts = ; + + }; + + gpio_keys_100ask { + compatible = "100ask,gpio_key"; + interrupt-parent = <&virtual_intc>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>, + <1 IRQ_TYPE_LEVEL_HIGH>, + <2 IRQ_TYPE_LEVEL_HIGH>, + <3 IRQ_TYPE_LEVEL_HIGH>; + }; + }; + ``` + + + + * 编译设备树： + 在Ubuntu的STM32MP157内核目录下执行如下命令, + 得到设备树文件：`arch/arm/boot/dts/stm32mp157c-100ask-512d-lcd-v1.dtb` + + ```shell + make dtbs + ``` + + * 复制到NFS目录： + + ```shell + $ cp arch/arm/boot/dts/stm32mp157c-100ask-512d-lcd-v1.dtb ~/nfs_rootfs/ + ``` + + * 开发板上挂载NFS文件系统 + + * vmware使用NAT(假设windowsIP为192.168.1.100) + + ```shell + [root@100ask:~]# mount -t nfs -o nolock,vers=3,port=2049,mountport=9999 + 192.168.1.100:/home/book/nfs_rootfs /mnt + ``` + + * vmware使用桥接，或者不使用vmware而是直接使用服务器：假设Ubuntu IP为192.168.1.137 + + ```shell + [root@100ask:~]# mount -t nfs -o nolock,vers=3 192.168.1.137:/home/book/nfs_rootfs /mnt + ``` + +* 更新设备树 + + ```shell + [root@100ask:~]# mount /dev/mmcblk2p2 /boot + [root@100ask:~]# cp /mnt/stm32mp157c-100ask-512d-lcd-v1.dtb /boot + [root@100ask:~]# sync + ``` + +* 重启开发板 + + + + + +##### 2. IMX6ULL + + * 修改`arch/arm/boot/dts/100ask_imx6ull-14x14.dts`，添加如下代码： + + ```shell + / { + virtual_intc: virtual_intc_100ask { + compatible = "100ask,virtual_intc"; + + interrupt-controller; + #interrupt-cells = <2>; + + interrupt-parent = <&intc>; + interrupts = ; + + }; + + gpio_keys_100ask { + compatible = "100ask,gpio_key"; + interrupt-parent = <&virtual_intc>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>, + <1 IRQ_TYPE_LEVEL_HIGH>, + <2 IRQ_TYPE_LEVEL_HIGH>, + <3 IRQ_TYPE_LEVEL_HIGH>; + }; + }; + ``` + + + + * 编译设备树： + 在Ubuntu的IMX6ULL内核目录下执行如下命令, + 得到设备树文件：`arch/arm/boot/dts/100ask_imx6ull-14x14.dtb` + + ```shell + make dtbs + ``` + + * 复制到NFS目录： + + ```shell + $ cp arch/arm/boot/dts/100ask_imx6ull-14x14.dtb ~/nfs_rootfs/ + ``` + +* 开发板上挂载NFS文件系统 + + * vmware使用NAT(假设windowsIP为192.168.1.100) + + ```shell + [root@100ask:~]# mount -t nfs -o nolock,vers=3,port=2049,mountport=9999 + 192.168.1.100:/home/book/nfs_rootfs /mnt + ``` + + * vmware使用桥接，或者不使用vmware而是直接使用服务器：假设Ubuntu IP为192.168.1.137 + + ```shell + [root@100ask:~]# mount -t nfs -o nolock,vers=3 192.168.1.137:/home/book/nfs_rootfs /mnt + ``` + + * 更新设备树 + + ```shell + [root@100ask:~]# cp /mnt/100ask_imx6ull-14x14.dtb /boot + [root@100ask:~]# sync + ``` + +* 重启开发板 + + + +#### 3.3 编译、安装驱动程序 + +* 编译： + + * 在Ubuntu上 + * 修改`003_virtual_int_controller_legacy`中的Makefile，指定内核路径`KERN_DIR`，在执行`make`命令即可。 + +* 安装： + + * 在开发板上 + + * 挂载NFS，复制文件，insmod，类似如下命令： + + ```shell + mount -t nfs -o nolock,vers=3 192.168.1.137:/home/book/nfs_rootfs /mnt + // 对于IMX6ULL，想看到驱动打印信息，需要先执行 + echo "7 4 1 7" > /proc/sys/kernel/printk + + insmod -f /mnt/virtual_int_controller.ko + // 安装virtual_int_controller之后即可进入/sys/kernel/irq目录查看分配的中断号 + + insmod -f /mnt/gpio_key_drv.ko + cat /proc/interrupts + + // 触发中断 + devmem 0xa01210 32 0x4000000 // imx6ull + devmem 0xa002121c 32 0x40000 // stm32mp157 + ``` + +* 观察内核打印的信息 diff --git a/IMX6ULL/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.tif b/IMX6ULL/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.tif new file mode 100644 index 0000000..2f2f457 Binary files /dev/null and b/IMX6ULL/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.tif differ diff --git a/IMX6ULL/doc_pic/08_Interrupt/17_链式中断控制器驱动程序编写_linear方式本.md b/IMX6ULL/doc_pic/08_Interrupt/17_链式中断控制器驱动程序编写_linear方式本.md new file mode 100644 index 0000000..21e0a1a --- /dev/null +++ b/IMX6ULL/doc_pic/08_Interrupt/17_链式中断控制器驱动程序编写_linear方式本.md @@ -0,0 +1,52 @@ +## 链式中断控制器驱动程序编写_linear方式 + +参考资料： + +* [linux kernel的中断子系统之（七）：GIC代码分析](http://www.wowotech.net/irq_subsystem/gic_driver.html) + +* Linux 4.9.88内核源码 + + * `Linux-4.9.88\drivers\gpio\gpio-mxc.c` + * `Linux-4.9.88\arch\arm\boot\dts\imx6ull.dtsi` + +* Linux 5.4内核源码 + + * `Linux-5.4\drivers\pinctrl\stm32\pinctrl-stm32mp157.c` + * `Linux-5.4\drivers\irqchip\irq-stm32-exti.c` + * `Linux-5.4\arch\arm\boot\dts\stm32mp151.dtsi` + +* 本节视频源码在GIT仓库里 + + ```shell + doc_and_source_for_drivers\ + IMX6ULL\source\08_Interrupt\ + 05_virtual_int_controller_linear_ok + + doc_and_source_for_drivers\ + STM32MP157\source\A7\08_Interrupt\ + 05_virtual_int_controller_linear_ok + ``` + + + +### 1. 两种方式的对比 + +linear、legacy方式，都是用来编写链式中断控制器驱动程序，它们的关系如下表所示。 + +| | legacy | linear | +| ------------ | --------------------------------------------- | --------------------- | +| 函数 | irq_domain_add_legacy | irq_domain_add_linear | +| irq_desc | 一次性分配完 | 用到再分配 | +| (hwirq,virq) | domain->linear_revmap[hwirq] = irq_data->irq; | 同左边 | + + + + +### 2. 编程 + + + +### 3. 上机实验 + +跟上节视频操作完全一样，参考《16_legacy方式代码的上机实验.md》 + diff --git a/IMX6ULL/doc_pic/08_Interrupt/18_层级中断控制器驱动程序编写与实验.md b/IMX6ULL/doc_pic/08_Interrupt/18_层级中断控制器驱动程序编写与实验.md new file mode 100644 index 0000000..c4568b9 --- /dev/null +++ b/IMX6ULL/doc_pic/08_Interrupt/18_层级中断控制器驱动程序编写与实验.md @@ -0,0 +1,128 @@ +## 层级中断控制器驱动程序编写与实验 + +参考资料： + +* [linux kernel的中断子系统之（七）：GIC代码分析](http://www.wowotech.net/irq_subsystem/gic_driver.html) + +* Linux 4.9.88内核源码 + + * `Linux-4.9.88\drivers\gpio\gpio-mxc.c` + * `Linux-4.9.88\arch\arm\boot\dts\imx6ull.dtsi` + +* Linux 5.4内核源码 + + * `Linux-5.4\drivers\pinctrl\stm32\pinctrl-stm32mp157.c` + * `Linux-5.4\drivers\irqchip\irq-stm32-exti.c` + * `Linux-5.4\arch\arm\boot\dts\stm32mp151.dtsi` + +* 本节视频源码在GIT仓库里 + + ```shell + doc_and_source_for_drivers\ + IMX6ULL\source\08_Interrupt\ + 06_virtual_int_controller_hierarchy_ok + + doc_and_source_for_drivers\ + STM32MP157\source\A7\08_Interrupt\ + 06_virtual_int_controller_hierarchy_ok + ``` + + + +### 1. 层级中断控制器的重要函数和结构体 + +#### 1.1 回顾处理流程 + +为方便描述，假设下级的链式中断控制器就是GPIO控制器。 + +下图中： + +* handleA、irq_dataA由GIC驱动提供 +* irq_dataB由GPIO驱动提供，不需要handleB + +![image-20210703101721943](pic/08_Interrupt/074_hierarchy_intc.png) + +* 假设GPIO模块下有4个引脚，都可以产生中断，分别链接到GIC的100~103号中断 +* GPIO就是一个层级中断控制器 +* 对于GPIO模块中0~3这四个hwirq，分配四个irq_desc，用到时再分配 +* 假设这4个irq_desc的序号为234~237 + * 在GIC domain中记录(100,234) (101,235)(102,236) (103,237) + * 在GPIO domain中记录(0,234) (1,235)(2,236) (3,237) +* 对于KEY，注册中断时就是：`request_irq(236, ...)` +* 按下KEY时： + * 程序从GIC中读取寄存器知道发生了102号中断，通过GIC irq_domain可以知道virq为236 + * 处理virq 236号中断：调用irq_desc[236].handle_irq，即handleA + * mask/ack中断: + * 调用irq_desc[236].irq_data->irq_chip的函数，即irq_dataB + * 它会调用父级irq_dataA->irq_chip的函数 + * 调用irq_desc[236].action链表中用户注册的函数 + * unmask中断: + * 调用irq_desc[236].irq_data->irq_chip的函数，即irq_dataB + * 它会调用父级irq_dataA->irq_chip的函数 + +#### 1.2 irq_domain的核心作用 + +怎么把handleA、GIC Domain和GPIO Domain、irq_chipA和irq_chipB这4个结构体组织起来，irq_domain是核心。 + +为方便描述，我们把上图中的层级中断控制器当做GPIO控制器。 + +我们从使用中断的流程来讲解。 + +* 在设备树里指定使用哪个中断 + + ```shell + gpio_keys_100ask { + compatible = "100ask,gpio_key"; + interrupt-parent = <&gpio5>; + interrupts = <3 IRQ_TYPE_EDGE_BOTH>, + }; + ``` + +* 内核解析、处理设备树的中断信息 + + * 根据`interrupt-parent`找到驱动程序注册的GPIO irq_domain + * GPIO irq_domain对设备树的解析 + * 使用GPIO irq_domain.ops中的translate或xlate函数解析设备树，得到hwirq和type + * 分配/找到irq_desc，得到virq + * 把(hwirq, virq)的关系存入GPIO irq_domain + * 把virq存入platform_device的resource中 + * 修改得到对应的GIC_hwirq，调用父级GIC irq_domain继续解析 + * 把(GIC_hwirq, virq)的关系存入GIC irq_domain + * **注意**：对于同一个硬件中断，它在两个irq_domain里的virq是相同的，hwirq可能不一样。 + * GPIO irq_domain对设备树的设置 + * 使用GPIO irq_domain.ops中的alloc函数进行设置 + * 替换irq_desc[virq].irq_data，里面有irq_chip改为irq_chipB，即GPIO的irq_chip + * 调用父级GIC irq_domain的alloc继续设置 + * 设置irq_desc[virq].handle_irq为GIC的handle_irq，即上图中的handleA + +* 用户的驱动程序注册中断 + + * 从platform_device的resource中得到中断号virq + * request_irq(virq, ..., func) + +* 发生中断、处理中断：处理流程见上面。 + + + +### 2. 硬件模型 + +下图中列出了链式中断控制器、层级中断控制器，本节课程之设计右边的层级中断控制器。 + +内核中有各类中断控制器的驱动程序，它们涉及的硬件过于复杂，从这些杂乱的代码中去讲清楚中断体系，比较难。 + +我们实现一些虚拟的中断控制器，如下图所示。 + +实际板子中，我们可以通过按键触发中断。 + +对于这些虚拟的中断控制器，我们没有真实按键，通过devmem指令写GIC的PENDING寄存器触发中断。 + + ![image-20210703133953035](pic/08_Interrupt/076_virtual_intc_hardware.png) + + + +### 3. 编程 + +会涉及2个驱动程序：虚拟的中断控制器驱动程序，按键驱动程序，以及对应的设备树。 + + + diff --git a/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/077_imx6ll_reserved_gic_int.png b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/077_imx6ll_reserved_gic_int.png new file mode 100644 index 0000000..7b3b3c5 Binary files /dev/null and b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/077_imx6ll_reserved_gic_int.png differ diff --git a/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/078_stm32mp157_reserved_gic_int.png b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/078_stm32mp157_reserved_gic_int.png new file mode 100644 index 0000000..f3a6818 Binary files /dev/null and b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/078_stm32mp157_reserved_gic_int.png differ diff --git a/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/079_GICD_ISPENDRn.png b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/079_GICD_ISPENDRn.png new file mode 100644 index 0000000..b083a8f Binary files /dev/null and b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/079_GICD_ISPENDRn.png differ diff --git a/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/080_GICD_ISPENDRn_calc.png b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/080_GICD_ISPENDRn_calc.png new file mode 100644 index 0000000..c313e7f Binary files /dev/null and b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/080_GICD_ISPENDRn_calc.png differ diff --git a/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/081_stm32mp157_gic_dts.png b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/081_stm32mp157_gic_dts.png new file mode 100644 index 0000000..f5f0aa3 Binary files /dev/null and b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/081_stm32mp157_gic_dts.png differ diff --git a/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/082_imx6ull_gic_dts.png b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/082_imx6ull_gic_dts.png new file mode 100644 index 0000000..062390d Binary files /dev/null and b/IMX6ULL/doc_pic/08_Interrupt/pic/08_Interrupt/082_imx6ull_gic_dts.png differ diff --git a/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/Makefile b/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/Makefile new file mode 100644 index 0000000..588910a --- /dev/null +++ b/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/Makefile @@ -0,0 +1,21 @@ + +# 1. 使用不同的开发板内核时, 一定要修改KERN_DIR +# 2. KERN_DIR中的内核要事先配置、编译, 为了能编译内核, 要先设置下列环境变量: +# 2.1 ARCH, 比如: export ARCH=arm64 +# 2.2 CROSS_COMPILE, 比如: export CROSS_COMPILE=aarch64-linux-gnu- +# 2.3 PATH, 比如: export PATH=$PATH:/home/book/100ask_roc-rk3399-pc/ToolChain-6.3.1/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin +# 注意: 不同的开发板不同的编译器上述3个环境变量不一定相同, +# 请参考各开发板的高级用户使用手册 + +KERN_DIR = /home/book/100ask_imx6ull-sdk/Linux-4.9.88 + +all: + make -C $(KERN_DIR) M=`pwd` modules + +clean: + make -C $(KERN_DIR) M=`pwd` modules clean + rm -rf modules.order + +obj-m += virtual_int_controller.o +obj-m += gpio_key_drv.o + diff --git a/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/gpio_key_drv.c b/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/gpio_key_drv.c new file mode 100644 index 0000000..dfd7d26 --- /dev/null +++ b/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/gpio_key_drv.c @@ -0,0 +1,125 @@ +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + + +struct gpio_key{ + char name[100]; + int irq; + int cnt; +} ; + +static struct gpio_key gpio_keys_100ask[100]; + +static irqreturn_t gpio_key_isr(int irq, void *dev_id) +{ + struct gpio_key *gpio_key = dev_id; + + + printk("gpio_key_isr %s cnt %d\n", gpio_key->name, gpio_key->cnt++); + + return IRQ_HANDLED; +} + +/* 1. 从platform_device获得GPIO + * 2. gpio=>irq + * 3. request_irq + */ +static int gpio_key_probe(struct platform_device *pdev) +{ + int err; + int i = 0; + int irq; + + printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__); + + + while (1) + { + irq = platform_get_irq(pdev, i); + if (irq <= 0) + break; + gpio_keys_100ask[i].irq = irq; + sprintf(gpio_keys_100ask[i].name, "100as_virtual_key%d", i); + + err = devm_request_irq(&pdev->dev, gpio_keys_100ask[i].irq, gpio_key_isr, IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, gpio_keys_100ask[i].name, &gpio_keys_100ask[i]); + printk("devm_request_irq %d for %s, err = %d\n", irq, gpio_keys_100ask[i].name, err); + i++; + } + + return 0; + +} + +static int gpio_key_remove(struct platform_device *pdev) +{ + return 0; +} + + +static const struct of_device_id ask100_keys[] = { + { .compatible = "100ask,gpio_key" }, + { }, +}; + +/* 1. 定义platform_driver */ +static struct platform_driver gpio_keys_driver = { + .probe = gpio_key_probe, + .remove = gpio_key_remove, + .driver = { + .name = "100ask_gpio_key", + .of_match_table = ask100_keys, + }, +}; + +/* 2. 在入口函数注册platform_driver */ +static int __init gpio_key_init(void) +{ + int err; + + printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__); + + err = platform_driver_register(&gpio_keys_driver); + + return err; +} + +/* 3. 有入口函数就应该有出口函数：卸载驱动程序时，就会去调用这个出口函数 + * 卸载platform_driver + */ +static void __exit gpio_key_exit(void) +{ + printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__); + + platform_driver_unregister(&gpio_keys_driver); +} + + +/* 7. 其他完善：提供设备信息，自动创建设备节点 */ + +module_init(gpio_key_init); +module_exit(gpio_key_exit); + +MODULE_LICENSE("GPL"); + + diff --git a/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_int_controller.c b/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_int_controller.c new file mode 100644 index 0000000..1e70896 --- /dev/null +++ b/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_int_controller.c @@ -0,0 +1,173 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +/* FIXME: for gpio_get_value() replace this with direct register read */ +#include +#include +#include +#include +#include + +static struct irq_domain *virtual_intc_domain; + +static int virtual_intc_get_hwirq(void) +{ + return get_random_int() & 0x3; +} + +static void virtual_intc_irq_handler(struct irq_desc *desc) +{ + /* 它的功能时分辨是哪一个hwirq, 调用对应的irq_desc[].handle_irq */ + int hwirq; + + struct irq_chip *chip = irq_desc_get_chip(desc); + + chained_irq_enter(chip, desc); + + /* a. 分辨中断 */ + hwirq = virtual_intc_get_hwirq(); + + /* b. 调用irq_desc[].handle_irq(handleC) */ + generic_handle_irq(irq_find_mapping(virtual_intc_domain, hwirq)); + + chained_irq_exit(chip, desc); +} + +static void virtual_intc_irq_ack(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static void virtual_intc_irq_mask(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static void virtual_intc_irq_mask_ack(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static void virtual_intc_irq_unmask(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static void virtual_intc_irq_eoi(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static struct irq_chip virtual_intc_irq_chip = { + .name = "100ask_virtual_intc", + .irq_ack = virtual_intc_irq_ack , + .irq_mask = virtual_intc_irq_mask , + .irq_mask_ack = virtual_intc_irq_mask_ack , + .irq_unmask = virtual_intc_irq_unmask , + .irq_eoi = virtual_intc_irq_eoi , +}; + +static int virtual_intc_irq_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw) +{ + /* 1. 给virq提供处理函数 + * 2. 提供irq_chip用来mask/unmask中断 + */ + + irq_set_chip_data(virq, h->host_data); + //irq_set_chip_and_handler(virq, &virtual_intc_irq_chip, handle_edge_irq); /* handle_edge_irq就是handleC */ + irq_set_chip_and_handler(virq, &virtual_intc_irq_chip, handle_level_irq); /* handle_level_irq就是handleC */ + //irq_set_nested_thread(virq, 1); + //irq_set_noprobe(virq); + + return 0; +} + + +static const struct irq_domain_ops virtual_intc_domain_ops = { + .xlate = irq_domain_xlate_onetwocell, + .map = virtual_intc_irq_map, +}; + +static int virtual_intc_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + int irq_to_parent; + int irq_base; + + /* 1. virutal intc 会向GIC发出n号中断 */ + /* 1.1 从设备树里获得virq_n */ + irq_to_parent = platform_get_irq(pdev, 0); + printk("virtual_intc_probe irq_to_parent = %d\n", irq_to_parent); + + /* 1.2 设置它的irq_desc[].handle_irq, 它的功能时分辨是哪一个hwirq, 调用对应的irq_desc[].handle_irq */ + irq_set_chained_handler_and_data(irq_to_parent, virtual_intc_irq_handler, NULL); + + + /* 2. 分配/设置/注册一个irq_domain */ + irq_base = irq_alloc_descs(-1, 0, 4, numa_node_id()); + printk("virtual_intc_probe irq_base = %d\n", irq_base); + + virtual_intc_domain = irq_domain_add_legacy(np, 4, irq_base, 0, + &virtual_intc_domain_ops, NULL); + + return 0; +} +static int virtual_intc_remove(struct platform_device *pdev) +{ + return 0; +} + + + +static const struct of_device_id virtual_intc_of_match[] = { + { .compatible = "100ask,virtual_intc", }, + { }, +}; + + +static struct platform_driver virtual_intc_driver = { + .probe = virtual_intc_probe, + .remove = virtual_intc_remove, + .driver = { + .name = "100ask_virtual_intc", + .of_match_table = of_match_ptr(virtual_intc_of_match), + } +}; + + +/* 1. 入口函数 */ +static int __init virtual_intc_init(void) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); + /* 1.1 注册一个platform_driver */ + return platform_driver_register(&virtual_intc_driver); +} + + +/* 2. 出口函数 */ +static void __exit virtual_intc_exit(void) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); + /* 2.1 反注册platform_driver */ + platform_driver_unregister(&virtual_intc_driver); +} + +module_init(virtual_intc_init); +module_exit(virtual_intc_exit); + +MODULE_LICENSE("GPL"); + + diff --git a/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_intc.dts b/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_intc.dts new file mode 100644 index 0000000..47dfab5 --- /dev/null +++ b/IMX6ULL/source/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_intc.dts @@ -0,0 +1,26 @@ + +#define n 100 + +/{ + virtual_intc: virtual_intc_100ask { + compatible = "100ask,virtual_intc"; + + interrupt-controller; + #interrupt-cells = <2>; + + interrupt-parent = <&intc>; + //interrupts = ; // stm32mp157 + interrupts = ; // imx6ull + + }; + + gpio_keys_100ask { + compatible = "100ask,gpio_key"; + interrupt-parent = <&virtual_intc>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>, + <1 IRQ_TYPE_LEVEL_HIGH>, + <2 IRQ_TYPE_LEVEL_HIGH>, + <3 IRQ_TYPE_LEVEL_HIGH>; + }; + +}; diff --git a/README.md b/README.md index c3c81b7..dfe0b65 100644 --- a/README.md +++ b/README.md @@ -293,7 +293,12 @@ git clone https://e.coding.net/weidongshan/linux/doc_and_source_for_drivers.git 15_链式中断控制器驱动程序编写 ``` - +* 2021.07.04 发布"Interrupt子系统" + + ```shell + 16_legacy方式代码的上机实验 + ``` + diff --git a/STM32MP157/doc_pic/08_Interrupt/15_链式中断控制器驱动程序编写.md b/STM32MP157/doc_pic/08_Interrupt/15_链式中断控制器驱动程序编写.md index a2d8e49..eaff2b2 100644 --- a/STM32MP157/doc_pic/08_Interrupt/15_链式中断控制器驱动程序编写.md +++ b/STM32MP157/doc_pic/08_Interrupt/15_链式中断控制器驱动程序编写.md @@ -15,7 +15,6 @@ * `Linux-5.4\drivers\irqchip\irq-stm32-exti.c` * `Linux-5.4\arch\arm\boot\dts\stm32mp151.dtsi` - * 本节视频源码在GIT仓库里 ```shell @@ -91,13 +90,15 @@ ### 2. 硬件模型 - 内核中有各类中断控制器的驱动程序，它们涉及的硬件过于复杂，从这些杂乱的代码中去讲清楚中断体系，比较难。 +下图中列出了链式中断控制器、层级中断控制器，本节课程只涉及左边的链式中断控制器。 - 我们实现一些虚拟的中断控制器，如下图所示。 +内核中有各类中断控制器的驱动程序，它们涉及的硬件过于复杂，从这些杂乱的代码中去讲清楚中断体系，比较难。 - 实际板子中，我们可以通过按键触发中断。 +我们实现一些虚拟的中断控制器，如下图所示。 - 对于这些虚拟的中断控制器，我们没有真实按键，通过devmem指令写GIC的PENDING寄存器触发中断。 +实际板子中，我们可以通过按键触发中断。 + +对于这些虚拟的中断控制器，我们没有真实按键，通过devmem指令写GIC的PENDING寄存器触发中断。 ![image-20210703133953035](pic/08_Interrupt/076_virtual_intc_hardware.png) diff --git a/STM32MP157/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.md b/STM32MP157/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.md new file mode 100644 index 0000000..7d96ea4 --- /dev/null +++ b/STM32MP157/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.md @@ -0,0 +1,283 @@ +## legacy方式代码的上机实验 + +参考资料： + +* [linux kernel的中断子系统之（七）：GIC代码分析](http://www.wowotech.net/irq_subsystem/gic_driver.html) + +* Linux 4.9.88内核源码 + + * `Linux-4.9.88\drivers\gpio\gpio-mxc.c` + * `Linux-4.9.88\arch\arm\boot\dts\imx6ull.dtsi` + +* Linux 5.4内核源码 + + * `Linux-5.4\drivers\pinctrl\stm32\pinctrl-stm32mp157.c` + * `Linux-5.4\drivers\irqchip\irq-stm32-exti.c` + * `Linux-5.4\arch\arm\boot\dts\stm32mp151.dtsi` + +* 芯片手册 + + * IMX6ULL: imx6ullrm.pdf + * STM32MP157: DM00327659.pdf + +* 本节视频源码在GIT仓库里 + + ```shell + doc_and_source_for_drivers\ + IMX6ULL\source\08_Interrupt\ + 04_virtual_int_controller_legacy_ok + + doc_and_source_for_drivers\ + STM32MP157\source\A7\08_Interrupt\ + 04_virtual_int_controller_legacy_ok + ``` + + + +### 1. 确定中断号n + +![](pic/08_Interrupt/076_virtual_intc_hardware.png) + +查看芯片手册，选择一个保留的、未使用的GIC SPI中断即可。 + +#### 1.1 IMX6ULL + +看芯片手册第3章： + +![image-20210704072332512](pic/08_Interrupt/077_imx6ll_reserved_gic_int.png) + +看上图，选择122号中断，它是SPI里的122号中断，GIC里的编号是(32+122)=154。 + + + +#### 1.2 STM32MP157 + +看芯片手册第21.2节： + +![image-20210704072802087](pic/08_Interrupt/078_stm32mp157_reserved_gic_int.png) + +看上图，选择210号中断，它是SPI里的210号中断，GIC里的编号是(32+210)=242。 + +### 2. 怎么触发中断 + +可以通过devmem命令直接写GIC的PENDING寄存区。 + +![image-20210704073305082](pic/08_Interrupt/079_GICD_ISPENDRn.png) + +GICD_ISPENDRn有多个寄存器，每个寄存器中每一位对应一个GIC中断，写入1就可以触发该中断。 + +写哪一个GICD_ISPENDRn寄存器？写哪一位？使用下列公式来确定： + +![image-20210704073518013](pic/08_Interrupt/080_GICD_ISPENDRn_calc.png) + +查看内核设备树文件imx6ull.dtsi、stm32mp151.dtsi，可以知道： + +* IMX6ULL的GIC Distributor 地址是：0x00a01000 + ![image-20210704103943340](pic/08_Interrupt/082_imx6ull_gic_dts.png) +* STM32MP157的GIC Distributor 地址是：0xa0021000 + ![image-20210704074850302](pic/08_Interrupt/081_stm32mp157_gic_dts.png) + +| 芯片 | SPI中断号 | GIC中断号 | n,bit | GICD_ISPENDRn地址 | 命令 | +| ---------- | --------- | --------- | ----- | ----------------- | ---------------------------- | +| IMX6LLL | 122 | 154 | 4,26 | 0xa01210 | devmem 0xa01210 32 0x4000000 | +| STM32MP157 | 210 | 242 | 7,18 | 0xa002121c | devmem 0xa002121c 32 0x40000 | + + + +### 3. 上机实验 + +#### 3.1 设置工具链 + +##### 1. STM32MP157 + + ```shell + export ARCH=arm + export CROSS_COMPILE=arm-buildroot-linux-gnueabihf- + export PATH=$PATH:/home/book/100ask_stm32mp157_pro-sdk/ToolChain/arm-buildroot-linux-gnueabihf_sdk-buildroot/bin + ``` + +##### 2. IMX6ULL + + ```shell + export ARCH=arm + export CROSS_COMPILE=arm-linux-gnueabihf- + export PATH=$PATH:/home/book/100ask_imx6ull-sdk/ToolChain/gcc-linaro-6.2.1-2016.11-x86_64_arm-linux-gnueabihf/bin + ``` + + + +#### 3.2 编译、替换设备树 + +##### 1. STM32MP157 + + * 修改`arch/arm/boot/dts/stm32mp157c-100ask-512d-lcd-v1.dts`，添加如下代码： + + ```shell + / { + virtual_intc: virtual_intc_100ask { + compatible = "100ask,virtual_intc"; + + interrupt-controller; + #interrupt-cells = <2>; + + interrupt-parent = <&intc>; + interrupts = ; + + }; + + gpio_keys_100ask { + compatible = "100ask,gpio_key"; + interrupt-parent = <&virtual_intc>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>, + <1 IRQ_TYPE_LEVEL_HIGH>, + <2 IRQ_TYPE_LEVEL_HIGH>, + <3 IRQ_TYPE_LEVEL_HIGH>; + }; + }; + ``` + + + + * 编译设备树： + 在Ubuntu的STM32MP157内核目录下执行如下命令, + 得到设备树文件：`arch/arm/boot/dts/stm32mp157c-100ask-512d-lcd-v1.dtb` + + ```shell + make dtbs + ``` + + * 复制到NFS目录： + + ```shell + $ cp arch/arm/boot/dts/stm32mp157c-100ask-512d-lcd-v1.dtb ~/nfs_rootfs/ + ``` + + * 开发板上挂载NFS文件系统 + + * vmware使用NAT(假设windowsIP为192.168.1.100) + + ```shell + [root@100ask:~]# mount -t nfs -o nolock,vers=3,port=2049,mountport=9999 + 192.168.1.100:/home/book/nfs_rootfs /mnt + ``` + + * vmware使用桥接，或者不使用vmware而是直接使用服务器：假设Ubuntu IP为192.168.1.137 + + ```shell + [root@100ask:~]# mount -t nfs -o nolock,vers=3 192.168.1.137:/home/book/nfs_rootfs /mnt + ``` + +* 更新设备树 + + ```shell + [root@100ask:~]# mount /dev/mmcblk2p2 /boot + [root@100ask:~]# cp /mnt/stm32mp157c-100ask-512d-lcd-v1.dtb /boot + [root@100ask:~]# sync + ``` + +* 重启开发板 + + + + + +##### 2. IMX6ULL + + * 修改`arch/arm/boot/dts/100ask_imx6ull-14x14.dts`，添加如下代码： + + ```shell + / { + virtual_intc: virtual_intc_100ask { + compatible = "100ask,virtual_intc"; + + interrupt-controller; + #interrupt-cells = <2>; + + interrupt-parent = <&intc>; + interrupts = ; + + }; + + gpio_keys_100ask { + compatible = "100ask,gpio_key"; + interrupt-parent = <&virtual_intc>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>, + <1 IRQ_TYPE_LEVEL_HIGH>, + <2 IRQ_TYPE_LEVEL_HIGH>, + <3 IRQ_TYPE_LEVEL_HIGH>; + }; + }; + ``` + + + + * 编译设备树： + 在Ubuntu的IMX6ULL内核目录下执行如下命令, + 得到设备树文件：`arch/arm/boot/dts/100ask_imx6ull-14x14.dtb` + + ```shell + make dtbs + ``` + + * 复制到NFS目录： + + ```shell + $ cp arch/arm/boot/dts/100ask_imx6ull-14x14.dtb ~/nfs_rootfs/ + ``` + +* 开发板上挂载NFS文件系统 + + * vmware使用NAT(假设windowsIP为192.168.1.100) + + ```shell + [root@100ask:~]# mount -t nfs -o nolock,vers=3,port=2049,mountport=9999 + 192.168.1.100:/home/book/nfs_rootfs /mnt + ``` + + * vmware使用桥接，或者不使用vmware而是直接使用服务器：假设Ubuntu IP为192.168.1.137 + + ```shell + [root@100ask:~]# mount -t nfs -o nolock,vers=3 192.168.1.137:/home/book/nfs_rootfs /mnt + ``` + + * 更新设备树 + + ```shell + [root@100ask:~]# cp /mnt/100ask_imx6ull-14x14.dtb /boot + [root@100ask:~]# sync + ``` + +* 重启开发板 + + + +#### 3.3 编译、安装驱动程序 + +* 编译： + + * 在Ubuntu上 + * 修改`003_virtual_int_controller_legacy`中的Makefile，指定内核路径`KERN_DIR`，在执行`make`命令即可。 + +* 安装： + + * 在开发板上 + + * 挂载NFS，复制文件，insmod，类似如下命令： + + ```shell + mount -t nfs -o nolock,vers=3 192.168.1.137:/home/book/nfs_rootfs /mnt + // 对于IMX6ULL，想看到驱动打印信息，需要先执行 + echo "7 4 1 7" > /proc/sys/kernel/printk + + insmod -f /mnt/virtual_int_controller.ko + // 安装virtual_int_controller之后即可进入/sys/kernel/irq目录查看分配的中断号 + + insmod -f /mnt/gpio_key_drv.ko + cat /proc/interrupts + + // 触发中断 + devmem 0xa01210 32 0x4000000 // imx6ull + devmem 0xa002121c 32 0x40000 // stm32mp157 + ``` + +* 观察内核打印的信息 diff --git a/STM32MP157/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.tif b/STM32MP157/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.tif new file mode 100644 index 0000000..2f2f457 Binary files /dev/null and b/STM32MP157/doc_pic/08_Interrupt/16_legacy方式代码的上机实验.tif differ diff --git a/STM32MP157/doc_pic/08_Interrupt/17_链式中断控制器驱动程序编写_linear方式本.md b/STM32MP157/doc_pic/08_Interrupt/17_链式中断控制器驱动程序编写_linear方式本.md new file mode 100644 index 0000000..21e0a1a --- /dev/null +++ b/STM32MP157/doc_pic/08_Interrupt/17_链式中断控制器驱动程序编写_linear方式本.md @@ -0,0 +1,52 @@ +## 链式中断控制器驱动程序编写_linear方式 + +参考资料： + +* [linux kernel的中断子系统之（七）：GIC代码分析](http://www.wowotech.net/irq_subsystem/gic_driver.html) + +* Linux 4.9.88内核源码 + + * `Linux-4.9.88\drivers\gpio\gpio-mxc.c` + * `Linux-4.9.88\arch\arm\boot\dts\imx6ull.dtsi` + +* Linux 5.4内核源码 + + * `Linux-5.4\drivers\pinctrl\stm32\pinctrl-stm32mp157.c` + * `Linux-5.4\drivers\irqchip\irq-stm32-exti.c` + * `Linux-5.4\arch\arm\boot\dts\stm32mp151.dtsi` + +* 本节视频源码在GIT仓库里 + + ```shell + doc_and_source_for_drivers\ + IMX6ULL\source\08_Interrupt\ + 05_virtual_int_controller_linear_ok + + doc_and_source_for_drivers\ + STM32MP157\source\A7\08_Interrupt\ + 05_virtual_int_controller_linear_ok + ``` + + + +### 1. 两种方式的对比 + +linear、legacy方式，都是用来编写链式中断控制器驱动程序，它们的关系如下表所示。 + +| | legacy | linear | +| ------------ | --------------------------------------------- | --------------------- | +| 函数 | irq_domain_add_legacy | irq_domain_add_linear | +| irq_desc | 一次性分配完 | 用到再分配 | +| (hwirq,virq) | domain->linear_revmap[hwirq] = irq_data->irq; | 同左边 | + + + + +### 2. 编程 + + + +### 3. 上机实验 + +跟上节视频操作完全一样，参考《16_legacy方式代码的上机实验.md》 + diff --git a/STM32MP157/doc_pic/08_Interrupt/18_层级中断控制器驱动程序编写与实验.md b/STM32MP157/doc_pic/08_Interrupt/18_层级中断控制器驱动程序编写与实验.md new file mode 100644 index 0000000..c4568b9 --- /dev/null +++ b/STM32MP157/doc_pic/08_Interrupt/18_层级中断控制器驱动程序编写与实验.md @@ -0,0 +1,128 @@ +## 层级中断控制器驱动程序编写与实验 + +参考资料： + +* [linux kernel的中断子系统之（七）：GIC代码分析](http://www.wowotech.net/irq_subsystem/gic_driver.html) + +* Linux 4.9.88内核源码 + + * `Linux-4.9.88\drivers\gpio\gpio-mxc.c` + * `Linux-4.9.88\arch\arm\boot\dts\imx6ull.dtsi` + +* Linux 5.4内核源码 + + * `Linux-5.4\drivers\pinctrl\stm32\pinctrl-stm32mp157.c` + * `Linux-5.4\drivers\irqchip\irq-stm32-exti.c` + * `Linux-5.4\arch\arm\boot\dts\stm32mp151.dtsi` + +* 本节视频源码在GIT仓库里 + + ```shell + doc_and_source_for_drivers\ + IMX6ULL\source\08_Interrupt\ + 06_virtual_int_controller_hierarchy_ok + + doc_and_source_for_drivers\ + STM32MP157\source\A7\08_Interrupt\ + 06_virtual_int_controller_hierarchy_ok + ``` + + + +### 1. 层级中断控制器的重要函数和结构体 + +#### 1.1 回顾处理流程 + +为方便描述，假设下级的链式中断控制器就是GPIO控制器。 + +下图中： + +* handleA、irq_dataA由GIC驱动提供 +* irq_dataB由GPIO驱动提供，不需要handleB + +![image-20210703101721943](pic/08_Interrupt/074_hierarchy_intc.png) + +* 假设GPIO模块下有4个引脚，都可以产生中断，分别链接到GIC的100~103号中断 +* GPIO就是一个层级中断控制器 +* 对于GPIO模块中0~3这四个hwirq，分配四个irq_desc，用到时再分配 +* 假设这4个irq_desc的序号为234~237 + * 在GIC domain中记录(100,234) (101,235)(102,236) (103,237) + * 在GPIO domain中记录(0,234) (1,235)(2,236) (3,237) +* 对于KEY，注册中断时就是：`request_irq(236, ...)` +* 按下KEY时： + * 程序从GIC中读取寄存器知道发生了102号中断，通过GIC irq_domain可以知道virq为236 + * 处理virq 236号中断：调用irq_desc[236].handle_irq，即handleA + * mask/ack中断: + * 调用irq_desc[236].irq_data->irq_chip的函数，即irq_dataB + * 它会调用父级irq_dataA->irq_chip的函数 + * 调用irq_desc[236].action链表中用户注册的函数 + * unmask中断: + * 调用irq_desc[236].irq_data->irq_chip的函数，即irq_dataB + * 它会调用父级irq_dataA->irq_chip的函数 + +#### 1.2 irq_domain的核心作用 + +怎么把handleA、GIC Domain和GPIO Domain、irq_chipA和irq_chipB这4个结构体组织起来，irq_domain是核心。 + +为方便描述，我们把上图中的层级中断控制器当做GPIO控制器。 + +我们从使用中断的流程来讲解。 + +* 在设备树里指定使用哪个中断 + + ```shell + gpio_keys_100ask { + compatible = "100ask,gpio_key"; + interrupt-parent = <&gpio5>; + interrupts = <3 IRQ_TYPE_EDGE_BOTH>, + }; + ``` + +* 内核解析、处理设备树的中断信息 + + * 根据`interrupt-parent`找到驱动程序注册的GPIO irq_domain + * GPIO irq_domain对设备树的解析 + * 使用GPIO irq_domain.ops中的translate或xlate函数解析设备树，得到hwirq和type + * 分配/找到irq_desc，得到virq + * 把(hwirq, virq)的关系存入GPIO irq_domain + * 把virq存入platform_device的resource中 + * 修改得到对应的GIC_hwirq，调用父级GIC irq_domain继续解析 + * 把(GIC_hwirq, virq)的关系存入GIC irq_domain + * **注意**：对于同一个硬件中断，它在两个irq_domain里的virq是相同的，hwirq可能不一样。 + * GPIO irq_domain对设备树的设置 + * 使用GPIO irq_domain.ops中的alloc函数进行设置 + * 替换irq_desc[virq].irq_data，里面有irq_chip改为irq_chipB，即GPIO的irq_chip + * 调用父级GIC irq_domain的alloc继续设置 + * 设置irq_desc[virq].handle_irq为GIC的handle_irq，即上图中的handleA + +* 用户的驱动程序注册中断 + + * 从platform_device的resource中得到中断号virq + * request_irq(virq, ..., func) + +* 发生中断、处理中断：处理流程见上面。 + + + +### 2. 硬件模型 + +下图中列出了链式中断控制器、层级中断控制器，本节课程之设计右边的层级中断控制器。 + +内核中有各类中断控制器的驱动程序，它们涉及的硬件过于复杂，从这些杂乱的代码中去讲清楚中断体系，比较难。 + +我们实现一些虚拟的中断控制器，如下图所示。 + +实际板子中，我们可以通过按键触发中断。 + +对于这些虚拟的中断控制器，我们没有真实按键，通过devmem指令写GIC的PENDING寄存器触发中断。 + + ![image-20210703133953035](pic/08_Interrupt/076_virtual_intc_hardware.png) + + + +### 3. 编程 + +会涉及2个驱动程序：虚拟的中断控制器驱动程序，按键驱动程序，以及对应的设备树。 + + + diff --git a/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/077_imx6ll_reserved_gic_int.png b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/077_imx6ll_reserved_gic_int.png new file mode 100644 index 0000000..7b3b3c5 Binary files /dev/null and b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/077_imx6ll_reserved_gic_int.png differ diff --git a/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/078_stm32mp157_reserved_gic_int.png b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/078_stm32mp157_reserved_gic_int.png new file mode 100644 index 0000000..f3a6818 Binary files /dev/null and b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/078_stm32mp157_reserved_gic_int.png differ diff --git a/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/079_GICD_ISPENDRn.png b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/079_GICD_ISPENDRn.png new file mode 100644 index 0000000..b083a8f Binary files /dev/null and b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/079_GICD_ISPENDRn.png differ diff --git a/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/080_GICD_ISPENDRn_calc.png b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/080_GICD_ISPENDRn_calc.png new file mode 100644 index 0000000..c313e7f Binary files /dev/null and b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/080_GICD_ISPENDRn_calc.png differ diff --git a/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/081_stm32mp157_gic_dts.png b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/081_stm32mp157_gic_dts.png new file mode 100644 index 0000000..f5f0aa3 Binary files /dev/null and b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/081_stm32mp157_gic_dts.png differ diff --git a/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/082_imx6ull_gic_dts.png b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/082_imx6ull_gic_dts.png new file mode 100644 index 0000000..062390d Binary files /dev/null and b/STM32MP157/doc_pic/08_Interrupt/pic/08_Interrupt/082_imx6ull_gic_dts.png differ diff --git a/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/Makefile b/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/Makefile new file mode 100644 index 0000000..e957daf --- /dev/null +++ b/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/Makefile @@ -0,0 +1,21 @@ + +# 1. 使用不同的开发板内核时, 一定要修改KERN_DIR +# 2. KERN_DIR中的内核要事先配置、编译, 为了能编译内核, 要先设置下列环境变量: +# 2.1 ARCH, 比如: export ARCH=arm64 +# 2.2 CROSS_COMPILE, 比如: export CROSS_COMPILE=aarch64-linux-gnu- +# 2.3 PATH, 比如: export PATH=$PATH:/home/book/100ask_roc-rk3399-pc/ToolChain-6.3.1/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin +# 注意: 不同的开发板不同的编译器上述3个环境变量不一定相同, +# 请参考各开发板的高级用户使用手册 + +KERN_DIR = /home/book/100ask_stm32mp157_pro-sdk/Linux-5.4 + +all: + make -C $(KERN_DIR) M=`pwd` modules + +clean: + make -C $(KERN_DIR) M=`pwd` modules clean + rm -rf modules.order + +obj-m += virtual_int_controller.o +obj-m += gpio_key_drv.o + diff --git a/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/gpio_key_drv.c b/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/gpio_key_drv.c new file mode 100644 index 0000000..dfd7d26 --- /dev/null +++ b/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/gpio_key_drv.c @@ -0,0 +1,125 @@ +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + + +struct gpio_key{ + char name[100]; + int irq; + int cnt; +} ; + +static struct gpio_key gpio_keys_100ask[100]; + +static irqreturn_t gpio_key_isr(int irq, void *dev_id) +{ + struct gpio_key *gpio_key = dev_id; + + + printk("gpio_key_isr %s cnt %d\n", gpio_key->name, gpio_key->cnt++); + + return IRQ_HANDLED; +} + +/* 1. 从platform_device获得GPIO + * 2. gpio=>irq + * 3. request_irq + */ +static int gpio_key_probe(struct platform_device *pdev) +{ + int err; + int i = 0; + int irq; + + printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__); + + + while (1) + { + irq = platform_get_irq(pdev, i); + if (irq <= 0) + break; + gpio_keys_100ask[i].irq = irq; + sprintf(gpio_keys_100ask[i].name, "100as_virtual_key%d", i); + + err = devm_request_irq(&pdev->dev, gpio_keys_100ask[i].irq, gpio_key_isr, IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, gpio_keys_100ask[i].name, &gpio_keys_100ask[i]); + printk("devm_request_irq %d for %s, err = %d\n", irq, gpio_keys_100ask[i].name, err); + i++; + } + + return 0; + +} + +static int gpio_key_remove(struct platform_device *pdev) +{ + return 0; +} + + +static const struct of_device_id ask100_keys[] = { + { .compatible = "100ask,gpio_key" }, + { }, +}; + +/* 1. 定义platform_driver */ +static struct platform_driver gpio_keys_driver = { + .probe = gpio_key_probe, + .remove = gpio_key_remove, + .driver = { + .name = "100ask_gpio_key", + .of_match_table = ask100_keys, + }, +}; + +/* 2. 在入口函数注册platform_driver */ +static int __init gpio_key_init(void) +{ + int err; + + printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__); + + err = platform_driver_register(&gpio_keys_driver); + + return err; +} + +/* 3. 有入口函数就应该有出口函数：卸载驱动程序时，就会去调用这个出口函数 + * 卸载platform_driver + */ +static void __exit gpio_key_exit(void) +{ + printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__); + + platform_driver_unregister(&gpio_keys_driver); +} + + +/* 7. 其他完善：提供设备信息，自动创建设备节点 */ + +module_init(gpio_key_init); +module_exit(gpio_key_exit); + +MODULE_LICENSE("GPL"); + + diff --git a/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_int_controller.c b/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_int_controller.c new file mode 100644 index 0000000..1e70896 --- /dev/null +++ b/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_int_controller.c @@ -0,0 +1,173 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +/* FIXME: for gpio_get_value() replace this with direct register read */ +#include +#include +#include +#include +#include + +static struct irq_domain *virtual_intc_domain; + +static int virtual_intc_get_hwirq(void) +{ + return get_random_int() & 0x3; +} + +static void virtual_intc_irq_handler(struct irq_desc *desc) +{ + /* 它的功能时分辨是哪一个hwirq, 调用对应的irq_desc[].handle_irq */ + int hwirq; + + struct irq_chip *chip = irq_desc_get_chip(desc); + + chained_irq_enter(chip, desc); + + /* a. 分辨中断 */ + hwirq = virtual_intc_get_hwirq(); + + /* b. 调用irq_desc[].handle_irq(handleC) */ + generic_handle_irq(irq_find_mapping(virtual_intc_domain, hwirq)); + + chained_irq_exit(chip, desc); +} + +static void virtual_intc_irq_ack(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static void virtual_intc_irq_mask(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static void virtual_intc_irq_mask_ack(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static void virtual_intc_irq_unmask(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static void virtual_intc_irq_eoi(struct irq_data *data) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); +} + +static struct irq_chip virtual_intc_irq_chip = { + .name = "100ask_virtual_intc", + .irq_ack = virtual_intc_irq_ack , + .irq_mask = virtual_intc_irq_mask , + .irq_mask_ack = virtual_intc_irq_mask_ack , + .irq_unmask = virtual_intc_irq_unmask , + .irq_eoi = virtual_intc_irq_eoi , +}; + +static int virtual_intc_irq_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw) +{ + /* 1. 给virq提供处理函数 + * 2. 提供irq_chip用来mask/unmask中断 + */ + + irq_set_chip_data(virq, h->host_data); + //irq_set_chip_and_handler(virq, &virtual_intc_irq_chip, handle_edge_irq); /* handle_edge_irq就是handleC */ + irq_set_chip_and_handler(virq, &virtual_intc_irq_chip, handle_level_irq); /* handle_level_irq就是handleC */ + //irq_set_nested_thread(virq, 1); + //irq_set_noprobe(virq); + + return 0; +} + + +static const struct irq_domain_ops virtual_intc_domain_ops = { + .xlate = irq_domain_xlate_onetwocell, + .map = virtual_intc_irq_map, +}; + +static int virtual_intc_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + int irq_to_parent; + int irq_base; + + /* 1. virutal intc 会向GIC发出n号中断 */ + /* 1.1 从设备树里获得virq_n */ + irq_to_parent = platform_get_irq(pdev, 0); + printk("virtual_intc_probe irq_to_parent = %d\n", irq_to_parent); + + /* 1.2 设置它的irq_desc[].handle_irq, 它的功能时分辨是哪一个hwirq, 调用对应的irq_desc[].handle_irq */ + irq_set_chained_handler_and_data(irq_to_parent, virtual_intc_irq_handler, NULL); + + + /* 2. 分配/设置/注册一个irq_domain */ + irq_base = irq_alloc_descs(-1, 0, 4, numa_node_id()); + printk("virtual_intc_probe irq_base = %d\n", irq_base); + + virtual_intc_domain = irq_domain_add_legacy(np, 4, irq_base, 0, + &virtual_intc_domain_ops, NULL); + + return 0; +} +static int virtual_intc_remove(struct platform_device *pdev) +{ + return 0; +} + + + +static const struct of_device_id virtual_intc_of_match[] = { + { .compatible = "100ask,virtual_intc", }, + { }, +}; + + +static struct platform_driver virtual_intc_driver = { + .probe = virtual_intc_probe, + .remove = virtual_intc_remove, + .driver = { + .name = "100ask_virtual_intc", + .of_match_table = of_match_ptr(virtual_intc_of_match), + } +}; + + +/* 1. 入口函数 */ +static int __init virtual_intc_init(void) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); + /* 1.1 注册一个platform_driver */ + return platform_driver_register(&virtual_intc_driver); +} + + +/* 2. 出口函数 */ +static void __exit virtual_intc_exit(void) +{ + printk("%s %s %d\n", __FILE__, __FUNCTION__, __LINE__); + /* 2.1 反注册platform_driver */ + platform_driver_unregister(&virtual_intc_driver); +} + +module_init(virtual_intc_init); +module_exit(virtual_intc_exit); + +MODULE_LICENSE("GPL"); + + diff --git a/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_intc.dts b/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_intc.dts new file mode 100644 index 0000000..002089d --- /dev/null +++ b/STM32MP157/source/A7/08_Interrupt/04_virtual_int_controller_legacy_ok/virtual_intc.dts @@ -0,0 +1,26 @@ + +#define n 100 + +/{ + virtual_intc: virtual_intc_100ask { + compatible = "100ask,virtual_intc"; + + interrupt-controller; + #interrupt-cells = <2>; + + interrupt-parent = <&intc>; + interrupts = ; // stm32mp157 + //interrupts = ; // imx6ull + + }; + + gpio_keys_100ask { + compatible = "100ask,gpio_key"; + interrupt-parent = <&virtual_intc>; + interrupts = <0 IRQ_TYPE_LEVEL_HIGH>, + <1 IRQ_TYPE_LEVEL_HIGH>, + <2 IRQ_TYPE_LEVEL_HIGH>, + <3 IRQ_TYPE_LEVEL_HIGH>; + }; + +};