NvmeQueues Entity Reference

This module implements the Nvme request/reply queues in RAM. More...

Inheritance diagram for NvmeQueues:

Entities
Behavioral	architecture

Libraries
ieee
unisim
work

Use Clauses
std_logic_1164
numeric_std
vcomponents
NvmeStoragePkg	Package <NvmeStoragePkg>
NvmeStorageIntPkg	Package <NvmeStorageIntPkg>

Generics
NumQueueEntries	integer := 8
	The number of entries per queue.
NvmeRegStride	integer := 4
	The doorbell register stride.
Simulate	boolean := True

Ports
clk	in	std_logic
		The interface clock line.
reset	in	std_logic
		The active high reset line.
streamIn	inout	AxisStreamType := AxisStreamInput
		Request queue entries.
streamOut	inout	AxisStreamType := AxisStreamOutput
		Replies and requests.

Detailed Description

This module implements the Nvme request/reply queues in RAM.

Author

Terry Barnaby (terry.nosp@m..bar.nosp@m.naby@.nosp@m.beam.nosp@m..ltd..nosp@m.uk)

Date

2020-04-08

Version

1.0.0

This module provides the ability to write a request to one of 4 Nvme request queues and receive the queued replies. This engine handles the queue location and informs the Nvme of the new queue entry by writing to the appropriate doorbell register. It supports queue memory reads from the Nvme device. When the Nvme writes to a reply queue, the queue reply message is directly sent on to the originator of the request as given in the CID field rather than stored in RAM. The process sending a requests simply uses a PcieWrite request to the appropriate queue's starting memory location. The NvmeQueue engine handles writing the queue entry data to the next available queue entry slot in RAM. The queue replies are converted into a PcieWrite request packet and sent on to the engine that created the original queue request. The address in the packet is set to the reply queues address (0x0201XXXXX) so that the originating engine can determine that this is a reply to its queued request. The module needs to know the dooerbell register stride of the actual NVMe devices in use. This is passed in as the NvmeRegStride parameter. The NumQueueEntries parameter defines the size of all queues.

Copyright

2020 Beam Ltd, Apache License, Version 2.0 Copyright 2020 Beam Ltd Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

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The documentation for this class was generated from the following file:

• /src/dune/source/DuneNvme/src/NvmeQueues.vhd