| commit | 56f1dbd6b7e30054d29b0da672e560e00be9d6e2 | [log] [tgz] |
|---|---|---|
| author | Eunchan Kim <eunchan@opentitan.org> | Thu Mar 31 14:04:17 2022 -0700 |
| committer | Eunchan Kim <github@eunchan.kim> | Fri Apr 01 13:27:00 2022 -0700 |
| tree | c464d498b6943fbf238cccb9e810ce15e5833668 | |
| parent | 9fd48839c2a08885a2e923cc3581a9c426c5c9a9 [diff] |
[spi_device] Change addr_latched as a pulse
Problem:
`addr_latched_i` in `spid_readsram` module is expected to be a pulse
signal. The `spi_readcmd` module generates the signal as a level by
comparing `addr_cnt_d` with all zero value.
As a result, the `strb` register in `spid_readsram` follows the
current address, which is increased by when a byte is sent to the
host system. However, the `spid_readsram` logic pushes the data into
the FIFO already. As the FIFO depth is 2, one more entry has been
added to the FIFO, which results the host system sees the a byte has
been shifted.
Resolution:
Revised the `addr_latched` logic to be a pulse. Either `addr_cnt_d`
or `addr_latched` can be revised. I chose the latter. Latching the
latched signal and generated a pulse.
Signed-off-by: Eunchan Kim <eunchan@opentitan.org>
OpenTitan is an open source silicon Root of Trust (RoT) project. OpenTitan will make the silicon RoT design and implementation more transparent, trustworthy, and secure for enterprises, platform providers, and chip manufacturers. OpenTitan is administered by lowRISC CIC as a collaborative project to produce high quality, open IP for instantiation as a full-featured product. See the OpenTitan site and OpenTitan docs for more information about the project.
This repository contains hardware, software and utilities written as part of the OpenTitan project. It is structured as monolithic repository, or “monorepo”, where all components live in one repository. It exists to enable collaboration across partners participating in the OpenTitan project.
The project contains comprehensive documentation of all IPs and tools. You can access it online at docs.opentitan.org.
Have a look at [CONTRIBUTING]({{< relref “CONTRIBUTING.md” >}}) and our documentation on project organization and processes for guidelines on how to contribute code to this repository.
Unless otherwise noted, everything in this repository is covered by the Apache License, Version 2.0 (see LICENSE for full text).