公开(公告)号：US11947457B2

公开(公告)日：2024-04-02

申请号：US18058105

申请日：2022-11-22

Applicant: Apple Inc.

Inventor： James Vash ,  Gaurav Garg ,  Brian P. Lilly ,  Ramesh B. Gunna ,  Steven R. Hutsell ,  Lital Levy-Rubin ,  Per H. Hammarlund ,  Harshavardhan Kaushikkar

IPC: G06F12/0815 ,  G06F12/0831

CPC classification number: G06F12/0815 ,  G06F12/0831 ,  G06F2212/1032

Abstract: A scalable cache coherency protocol for system including a plurality of coherent agents coupled to one or more memory controllers is described. The memory controller may implement a precise directory for cache blocks from the memory to which the memory controller is coupled. Multiple requests to a cache block may be outstanding, and snoops and completions for requests may include an expected cache state at the receiving agent, as indicated by a directory in the memory controller when the request was processed, to allow the receiving agent to detect race conditions. In an embodiment, the cache states may include a primary shared and a secondary shared state. The primary shared state may apply to a coherent agent that bears responsibility for transmitting a copy of the cache block to a requesting agent. In an embodiment, at least two types of snoops may be supported: snoop forward and snoop back.

公开(公告)号：US11675722B2

公开(公告)日：2023-06-13

申请号：US17337805

申请日：2021-06-03

Applicant: Apple Inc.

Inventor： Sergio Kolor ,  Sergio V. Tota ,  Tzach Zemer ,  Sagi Lahav ,  Jonathan M. Redshaw ,  Per H. Hammarlund ,  Eran Tamari ,  James Vash ,  Gaurav Garg ,  Lior Zimet ,  Harshavardhan Kaushikkar ,  Steven Fishwick ,  Steven R. Hutsell ,  Shawn M. Fukami

IPC: G06F13/40 ,  G06F15/173

CPC classification number: G06F13/4027 ,  G06F13/4022 ,  G06F15/17375 ,  G06F15/17381

Abstract: In an embodiment, a system on a chip (SOC) comprises a semiconductor die on which circuitry is formed, wherein the circuitry comprises a plurality of agents and a plurality of network switches coupled to the plurality of agents. The plurality of network switches are interconnected to form a plurality of physical and logically independent networks. A first network of the plurality of physically and logically independent networks is constructed according to a first topology and a second network of the plurality of physically and logically independent networks is constructed according to a second topology that is different from the first topology. For example, the first topology may a ring topology and the second topology may be a mesh topology. In an embodiment, coherency may be enforced on the first network and the second network may be a relaxed order network.

公开(公告)号：US20230169003A1

公开(公告)日：2023-06-01

申请号：US18160575

申请日：2023-01-27

Applicant: Apple Inc.

Inventor： James Vash ,  Gaurav Garg ,  Brian P. Lilly ,  Ramesh B. Gunna ,  Steven R. Hutsell ,  Lital Levy-Rubin ,  Per H. Hammarlund ,  Harshavardhan Kaushikkar

IPC: G06F12/0815 ,  G06F12/0831

CPC classification number: G06F12/0815 ,  G06F12/0831 ,  G06F2212/1032

Abstract: A scalable cache coherency protocol for system including a plurality of coherent agents coupled to one or more memory controllers is described. The memory controller may implement a precise directory for cache blocks from the memory to which the memory controller is coupled. Multiple requests to a cache block may be outstanding, and snoops and completions for requests may include an expected cache state at the receiving agent, as indicated by a directory in the memory controller when the request was processed, to allow the receiving agent to detect race conditions. In an embodiment, the cache states may include a primary shared and a secondary shared state. The primary shared state may apply to a coherent agent that bears responsibility for transmitting a copy of the cache block to a requesting agent. In an embodiment, at least two types of snoops may be supported: snoop forward and snoop back.

公开(公告)号：US20230064526A1

公开(公告)日：2023-03-02

申请号：US17657506

申请日：2022-03-31

Applicant: Apple Inc.

Inventor： Sagi Lahav ,  Lital Levy - Rubin ,  Gaurav Garg ,  Gerard R. Williams, III ,  Samer Nassar ,  Per H. Hammarlund ,  Harshavardhan Kaushikkar ,  Srinivasa Rangan Sridharan ,  Jeff Gonion

IPC: G06F9/46 ,  G06F13/16

Abstract: Techniques are disclosed relating to an I/O agent circuit. The I/O agent circuit may include one or more queues and a transaction pipeline. The I/O agent circuit may issue, to the transaction pipeline from a queue of the one or more queues, a transaction of a series of transactions enqueued in a particular order. The I/O agent circuit may generate, at the transaction pipeline, a determination to return the transaction to the queue based on a detection of one or more conditions being satisfied. Based on the determination, the I/O agent circuit may reject, at the transaction pipeline, up to a threshold number of transactions that issued from the queue after the transaction issued. The I/O agent circuit may insert the transaction at a head of the queue such that the transaction is enqueued at the queue sequentially first for the series of transactions according to the particular order.

公开(公告)号：US20230056044A1

公开(公告)日：2023-02-23

申请号：US17821296

申请日：2022-08-22

Applicant: Apple Inc.

Inventor： Per H. Hammarlund ,  Lior Zimet ,  James Vash ,  Gaurav Garg ,  Sergio Kolor ,  Harshavardhan Kaushikkar ,  Ramesh B. Gunna ,  Steven R. Hutsell

IPC: G06F13/28 ,  G06F12/0815 ,  G06F12/109

Abstract: A system including a plurality of processor cores, a plurality of graphics processing units, a plurality of peripheral circuits, and a plurality of memory controllers is configured to support scaling of the system using a unified memory architecture.