我们正在设计一张具有PCIe接口的C6657板卡，用于和PC互连。
板卡通过PC主板的PCIe插槽供电。PC为RC，DSP为EP。
DSP的boot模式为PCIe。
参考 SPRAC59A PCIe FAQ文档里1.2章节 - Power Sequencing
The following steps show the power sequencing.
1. PCIe slot on the PC host provides power and reference clock to the PCIe module on the EVM.
2. PCIe boot code on the EVM initializes the C66x PCIe module and waits for the link coming up.
3. PCIe root complex (RC) in the PC host is powered up and a link is established between the PCIe RC
in the host and PCIe end point (EP) in the EVM.
4. PC host enumeration (BIOS) starts to scan the PCIe bus.
5. PCIe end point in the EVM is enumerated and registered in the operating system (OS) of the host PC.
我的问题是：由于DSP是通过主板的PCIe插槽供电，当启动PC电源的时候，主板和DSP同时上电。当然，主板和DSP各自上电都有一定的时间/时序。
如何确保DSP端RBL（步骤2）一定先于PC端RC（步骤3）完成？
有什么设计建议吗？
