System for asynchronous DMA command completion notification wherein the DMA command comprising a tag belongs to a plurality of tag groups

US7546393B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Michael Norman Day · Round Rock, US
• Harm Peter Hofstee · Austin, US
• Charles Ray Johns · Austin, US
• Peichum Peter Liu · Austin, US
• Thuong Quang Truong · Austin, US
• Takeshi Yamazaki · Tokyo, JP

Key dates

• Filing date: Apr 2, 2007
• Grant date: Jun 9, 2009
• Expiry date: Jun 15, 2027

Classification

• Technology area (CPC G): Physics
• CPC primary: G06F13/28
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

The present invention provides for a system comprising a DMA queue configured to receive a DMA command comprising a tag, wherein the tag belongs to one of a plurality of tag groups. A counter couples to the DMA queue and is configured to increment a tag group count of the tag group to which the tag belongs upon receipt of the DMA command by the DMA queue and to decrement the tag group count upon execution of the DMA command. A tag group count status register couples to the counter and is configured to store the tag group count for each of the plurality of tag groups. And the tag group count status register is further configured to receive a request for a tag group status and to respond to the request for the tag group status.