[risc-v][common64] Make rt_hw_cpu_shutdown weak to resolve multiple definition with RT_USING_DM

[Copilot]

When RT_USING_DM is enabled, both libcpu/risc-v/common64/cpuport.c and components/drivers/core/power.c define rt_hw_cpu_shutdown, causing linker failure.

Changes

• Mark rt_hw_cpu_shutdown in libcpu/risc-v/common64/cpuport.c as rt_weak

This allows the power management implementation to override the default cpuport version when device manager is enabled, while maintaining the fallback for configurations without DM.

-void rt_hw_cpu_shutdown(void)
+rt_weak void rt_hw_cpu_shutdown(void)

Affects RISC-V 64-bit architectures: virt64, c906, c908, ur-cp100.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[Bug] 当打开RT_USING_DM时rt_hw_cpu_shutdown 重复定义</issue_title>
<issue_description>### RT-Thread Version

upstream

Hardware Type/Architectures

riscv

Develop Toolchain

GCC

Describe the bug

Issue: Multiple definition of rt_hw_cpu_shutdown when RT_USING_DM is enabled.

Description:
When the device manager feature is enabled (RT_USING_DM), both rt-thread/libcpu/risc-v/common64/cpuport.c and rt-thread/components/drivers/core/power.c define rt_hw_cpu_shutdown, causing a linker error.

Solution:
Make the rt_hw_cpu_shutdown function in cpuport.c weak using the rt_weak attribute. This allows the power management implementation to override the default cpuport implementation when device manager is enabled.

Other additional context

No response</issue_description>

<agent_instructions>可以按照solution的方式进行修正。</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes [Bug] 当打开RT_USING_DM时rt_hw_cpu_shutdown 重复定义 #11099

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[github-actions]

📌 Code Review Assignment

🏷️ Tag: libcpu_riscv

Reviewers: @Yaochenger

Changed Files (Click to expand)

• libcpu/risc-v/common64/cpuport.c

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📊 Current Review Status (Last Updated: 2025-12-29 07:37 CST)

• ⌛ @Yaochenger Pending Review

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