1. 用zip解压缩Nationstech.N32G45x_DFP.1.0.0.pack，提取到Nationstech.N32G45x_DFP.1.0.0文件夹。

把Nationstech.N32G45x_DFP.1.0.0.pdsc 改为Nationstech.N32G45x_DFP.pdsc
再压缩成Nationstech.N32G45x_DFP.1.0.0.zip，名称改为Nationstech.N32G45x_DFP.1.0.0.pack

2. 复制库

2.1 把
Nationstech.N32G45x_DFP.1.0.0.pdsc、
Nationstech.N32G45x_DFP.1.0.0.pack、.Nationstech.N32G45x_DFP.1.0.0.pack.size
C:\Users\xxx\AppData\Roaming\CMSIS-Packs.cache

2.2 删除.installed_devices_boards_books.xml，便于device重新显示出来
2.3 在.content_https___www_keil_com_pack_index_pidx.xml下增加如下内容

      <package name="N32G45x_DFP">
        <description>Nationstech N32G45x Series Device Support and Examples</description>
        <versions>
          <version name="1.0.0">
            <description>update N32G45x firmware .</description>
            <properties>
              <property name="type">cmsis.pack</property>
              <property name="vendor.name">Nationstech</property>
              <property name="pack.name">N32G45x_DFP</property>
              <property name="version.name">1.0.0</property>
              <property name="archive.url">http://nationstech.com/data/documents/pack/Nationstech.N32G45x_DFP.1.0.0.pack</property>
              <property name="archive.name">Nationstech.N32G45x_DFP.1.0.0.pack</property>
              <property name="archive.size">586274</property>
              <property name="dest.folder">Nationstech/N32G45x_DFP/1.0.0</property>
              <property name="pdsc.name">Nationstech.N32G45x_DFP.pdsc</property>
              <property name="date">2021-03-02</property>
            </properties>
            <outline>
              <keyword name="Nationstech" />
              <keyword name="Device Support" />
              <keyword name="N32G45x" />
              <devicefamily name="N32G45x Series">
                <description>N32G45x is a new 32-bit high performance, low power consumption universal microcontroller family powered by the ARM Cortex-M4 RISC core,which targeted at various MCU application areas.
GD32 family integrates features to simplify system design and provide customers wide range of comprehensive and superior cost effective MCU portfolios with proven technology and great innovation.
GD32 family includes entry line, performance line and connectivity line currently.</description>
                <property name="vendor.name">Nationstech</property>
                <property name="vendor.id">123</property>
              </devicefamily>
              <component name="Device / n32g45x_std_periph_driver / ADC">
                <description>Analog-to-digital converter (ADC) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / BKP">
                <description>Backup register(BKP) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / CAN">
                <description>Controller Area Network (CAN) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / CRC">
                <description>Cyclic Redundancy Check (CRC) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / CTC">
                <description>Clock trim controller (CTC) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / DAC">
                <description>Digital-to-analog converter (DAC) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / DBG">
                <description>Debug (DBG) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / DMA">
                <description>Direct Memory Access (DMA) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / EXMC">
                <description>External memory controller(EXMC) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / EXTI">
                <description>External Interrupt/Event (EXTI) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / FMC">
                <description>Flash Memory Controller (FMC) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / FWDGT">
                <description>Free watchdog timer(FWDGT) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / GPIO">
                <description>General-purpose and Alternate-function I/Os (GPIO) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / I2C">
                <description>Inter-integrated Circuit (I2C) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / MISC">
                <description>MISC driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / PMU">
                <description>Power Managment Unit(PMU) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / RCU">
                <description>Reset and Clock Control (RCU) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / RTC">
                <description>Real-time Clock (RTC) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / SPI_I2S">
                <description>Serial Peripheral Interface / Inter-IC Sound (SPI_I2S) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / TIMER">
                <description>TIMER driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / USART">
                <description>Universal Synchronous Asynchronous Receiver Transmitter (USART) driver for N32G45x Devices</description>
              </component>
              <component name="Device / n32g45x_std_periph_driver / WWDGT">
                <description>Window Watchdog Timer (WWDGT) driver for N32G45x Devices</description>
              </component>
              <component name="Device / EVAL / N32G45x">
                <description>Firmware functions to manage Leds, Keys, COM ports</description>
              </component>
              <component name="Device / N32G45x_libopt">
                <description>Configuration file</description>
              </component>
              <component name="Device / Startup">
                <description>System Startup for GigaDevice N32G45x  Devices</description>
              </component>
            </outline>
          </version>
        </versions>
      </package> 

3. 重启eclipse，点击CMSIS Pack图标

显示未安装，

右键install

eclipse会把.cache中Nationstech.N32G45x_DFP.1.0.0.pack解压缩如下图

4. 在工程上右键Properties，点击Setting之后，等待几秒后，.cache文件夹中生成.installed_devices_boards_books.xml，界面中可以看到N32G45x Series。