Bug 410 - Design Bus Protocol suitable for speculative execution
Summary: Design Bus Protocol suitable for speculative execution
Status: CONFIRMED
Alias: None
Product: Libre-SOC's first SoC
Classification: Unclassified
Component: Source Code (show other bugs)
Version: unspecified
Hardware: Other Linux
: --- enhancement
Assignee: Luke Kenneth Casson Leighton
URL:
Depends on:
Blocks: 383
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Reported: 2020-07-01 14:37 BST by Luke Kenneth Casson Leighton
Modified: 2021-10-28 18:33 BST (History)
1 user (show)

See Also:
NLnet milestone: NLNet.2019.10.043.Wishbone
total budget (EUR) for completion of task and all subtasks: 0
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Description Luke Kenneth Casson Leighton 2020-07-01 14:37:23 BST 
Standard processor Bus APIs (Wishbone) operate on an atomic "take it or leave it" protocol.  This is unsuitable for speculative execution which needs a "Contract of Sale" protocol involving "offer, exchange, complete" that may be cancelled or declined.  This type of Bus Protocol therefore needs to be designed, implemented and documented.
Comment 1 Luke Kenneth Casson Leighton 2021-10-28 18:32:48 BST 
thanks to octavius:
http://lists.libre-soc.org/pipermail/libre-soc-dev/2021-October/003974.html