[riscv]统一plic和中断控制的接口实现

[heyuanjie87]

拉取/合并请求描述：(PR description)

[

为什么提交这份PR (why to submit this PR)

你的解决方案是什么 (what is your solution)

请提供验证的bsp和config (provide the config and bsp)

• BSP:
  k230 qemu

• .config:

• action:

]

当前拉取/合并请求的状态 Intent for your PR

必须选择一项 Choose one (Mandatory):

• 本拉取/合并请求是一个草稿版本 This PR is for a code-review and is intended to get feedback
• 本拉取/合并请求是一个成熟版本 This PR is mature, and ready to be integrated into the repo

代码质量 Code Quality：

我在这个拉取/合并请求中已经考虑了 As part of this pull request, I've considered the following:

• 已经仔细查看过代码改动的对比 Already check the difference between PR and old code
• 代码风格正确，包括缩进空格，命名及其他风格 Style guide is adhered to, including spacing, naming and other styles
• 没有垃圾代码，代码尽量精简，不包含#if 0代码，不包含已经被注释了的代码 All redundant code is removed and cleaned up
• 所有变更均有原因及合理的，并且不会影响到其他软件组件代码或BSP All modifications are justified and not affect other components or BSP
• 对难懂代码均提供对应的注释 I've commented appropriately where code is tricky
• 代码是高质量的 Code in this PR is of high quality
• 已经使用formatting 等源码格式化工具确保格式符合RT-Thread代码规范 This PR complies with RT-Thread code specification
• 如果是新增bsp, 已经添加ci检查到.github/workflows/bsp_buildings.yml 详细请参考链接BSP自查

[zhangjing0303]

1、plic_base的赋值：建议把plic_base 定义为全局变量，各bsp在rt_hw_board_init中对plic_base赋值，同时在plic_init中判断下该值是不是NULL；
2、plic_init 是不是还是放到plic.c中定义合理些？

[heyuanjie87]

1：后续可能会支持从设备树读取基地址，所以暂时就保持用配置的方式，而且这个pr我也不想太多改动bsp
2: plic.c只提供plic的操作接口并且也提供了属于它这个层次的init接口，而plic_init更偏向于一个上层应用的角色

[Copilot]

Pull Request Overview

This PR integrates the PLIC component into the interrupt control interface for RISCV by updating the build scripts.

• Adds a new SConscript file for the plic component.
• Updates the main SConscript to include the plic SConscript file under the common64_arch condition.

Reviewed Changes

Copilot reviewed 2 out of 18 changed files in this pull request and generated 1 comment.

File	Description
libcpu/risc-v/plic/SConscript	New build script for the plic component.
libcpu/risc-v/SConscript	Updated to include the plic SConscript when building for common64 CPUs.

Files not reviewed (16)

• bsp/qemu-virt64-riscv/driver/board.c: Language not supported
• libcpu/risc-v/common64/interrupt.c: Language not supported
• libcpu/risc-v/common64/interrupt.h: Language not supported
• libcpu/risc-v/plic/plic.c: Language not supported
• libcpu/risc-v/plic/plic.h: Language not supported
• libcpu/risc-v/t-head/c906/interrupt.c: Language not supported
• libcpu/risc-v/t-head/c906/interrupt.h: Language not supported
• libcpu/risc-v/t-head/c906/plic.c: Language not supported
• libcpu/risc-v/t-head/c906/plic.h: Language not supported
• libcpu/risc-v/t-head/c908/interrupt.c: Language not supported
• libcpu/risc-v/t-head/c908/interrupt.h: Language not supported
• libcpu/risc-v/t-head/c908/plic.c: Language not supported
• libcpu/risc-v/t-head/c908/plic.h: Language not supported
• libcpu/risc-v/virt64/interrupt.c: Language not supported
• libcpu/risc-v/virt64/plic.c: Language not supported
• libcpu/risc-v/virt64/plic.h: Language not supported

Comments suppressed due to low confidence (2)

libcpu/risc-v/plic/SConscript:11

• [nitpick] If this script is specific to the plic component, consider renaming the group from 'libcpu' to 'plic' for clearer organization.

group = DefineGroup('libcpu', src, depend = [''], CPPPATH = CPPPATH)

libcpu/risc-v/SConscript:16

• Verify that including the plic SConscript exclusively under the common64_arch condition is intentional; if support is required for other CPU types, adjust the condition accordingly.

group += SConscript(os.path.join('plic', 'SConscript'))

[supperthomas]

这个AI仅供参考，以实际使用为准。

[heyuanjie87]

ai推荐的这个改动在本地编译也没问题