当我们通过IP目录在Vivado中创建一些IP内核时,将使用xdc文件生成一些内核。
在这个xdc文件中,它包括时序或物理约束。
以DDR3控制器为例,用核心生成xdc文件。
它包括时序约束和物理约束,因为当我们在MIG中配置内核时,我们需要为DDR3端口分配引脚。
当我将DDR3控制器放入我们的设计中时,我尝试将ddr3.xdc文件直接添加到我的设计约束集中。
然而,当我实现设计时,我遇到了来自ddr3.xdc的一些严重警告,因为似乎DDR3控制器的某些内部信号在xdc中受到限制,但是Vivado无法找到它们。
这可能发生在其xdc文件试图限制IP内部逻辑的其他核心中。所以我想知道在这种情况下,我如何使用这个用IP核生成的xdc文件?
是否有任何标准的方法来使用它们摆脱cr
tical警告?
非常感谢。
以上来自于谷歌翻译
以下为原文
When we create some IP cores in Vivado through IP Catalog, some cores will be generated with a xdc file. Inside this xdc files, it includes timing or physical constrains.
Take DDR3 controller as an example, a xdc file is generated with core. It inlcudes both timing constrain and physical constrains since we need assign pins for DDR3 ports when we configure the core in MIG.
When I put the DDR3 controller into our design, I try to do is add the ddr3.xdc file directly into my design constrain set. However, when I implement the design, I confronted some critical warnings from ddr3.xdc since it seems some inner signals of DDR3 controller are constrained in xdc, but Vivado can not find them.
This may happen in other cores whose xdc file try to constrain inner logics inside the IP. So I wonder in this case, how can I use this xdc file generated with IP cores? Is there any standard approach to use them to get rid of the crtical warnings?
Thanks very much.