History log of /freebsd-11.0-release/sys/dev/altera/sdcard/altera_sdcard_nexus.c
Revision Date Author Comments
(<<< Hide modified files)
(Show modified files >>>)
# 303975 11-Aug-2016 gjb

Copy stable/11@r303970 to releng/11.0 as part of the 11.0-RELEASE
cycle.

Prune svn:mergeinfo from the new branch, and rename it to RC1.

Update __FreeBSD_version.

Use the quarterly branch for the default FreeBSD.conf pkg(8) repo and
the dvd1.iso packages population.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

# 302408 08-Jul-2016 gjb

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation


# 257336 29-Oct-2013 nwhitehorn

These nexus attachments do not execute a real probe and so need
BUS_PROBE_NOWILDCARD set.


# 245380 13-Jan-2013 rwatson

Merge Perforce changeset 219952 to head:

Make different bus attachments for Altera and Terasice
device drivers share the same devclass_t.

Sponsored by: DARPA, AFRL


# 239675 25-Aug-2012 rwatson

Add a device driver for the Altera University Program SD Card IP Core,
which can be synthesised in Altera FPGAs. An altera_sdcardc device
probes during the boot, and /dev/altera_sdcard devices come and go as
inserted and removed. The device driver attaches directly to the
Nexus, as is common for system-on-chip device drivers.

This IP core suffers a number of significant limitations, including a
lack of interrupt-driven I/O -- we must implement timer-driven polling,
only CSD 0 cards (up to 2G) are supported, there are serious memory
access issues that require the driver to verify writes to memory-mapped
buffers, undocumented alignment requirements, and erroneous error
returns. The driver must therefore work quite hard, despite a fairly
simple hardware-software interface. The IP core also supports at most
one outstanding I/O at a time, so is not a speed demon.

However, with the above workarounds, and subject to performance
problems, it works quite reliably in practice, and we can use it for
read-write mounts of root file systems, etc.

Sponsored by: DARPA, AFRL