公开(公告)号：US20080065855A1

公开(公告)日：2008-03-13

申请号：US11531293

申请日：2006-09-13

申请人： Matthew E. King ,  Peichun P. Liu ,  David Mui ,  Mydung N. Pham ,  Jieming Qi ,  Thuong Q. Truong

发明人： Matthew E. King ,  Peichun P. Liu ,  David Mui ,  Mydung N. Pham ,  Jieming Qi ,  Thuong Q. Truong

IPC分类号： G06F12/00 ,  G06F13/28

CPC分类号： G06F13/28 ,  G06F12/1045 ,  G06F12/1081 ,  G06F12/145

摘要： A memory management unit (MMU) performs address translation and protection using a segment table and page table model. Each DMA queue entry may include a MMU-miss dependency flag. The DMA issue mechanism uses the MMU-miss dependency flag to block the issue of commands that are known to result in a translation miss. However, the direct memory access engine does not block subsequent DMA commands from being issued until they receive a translation miss. When the MMU completes processing of a miss, the MMU sends a miss clear signal to the DMA control unit to reset all MMU-miss dependency flags. When the MMU sends a miss clear signal, the DMA control unit will reset all DMA queue entries with MMU-miss dependency flags set. DMA commands in the DMA queue that were blocked from issue by the MMU-miss dependency flag may now be selected by the DMA control unit for issue.

摘要翻译： 存储器管理单元（MMU）使用段表和页表模型执行地址转换和保护。 每个DMA队列条目可以包括MMU-miss依赖标志。 DMA问题机制使用MMU-miss依赖标志来阻止已知导致翻译缺失的命令的问题。 然而，直接存储器访问引擎不会阻止随后的DMA命令被发出，直到它们接收到转换未命中。 当MMU完成未命中的处理时，MMU向DMA控制单元发送未命中清除信号，以复位所有MMU-miss依赖标志。 当MMU发送未命中清除信号时，DMA控制单元将重置所有设置了MMU-miss依赖标志的DMA队列条目。 DMA控制单元现在可以由DMA控制单元选择DMA队列中的DMA命令，由MMU-miss依赖标志阻止发布。