xdma(4) interface.
This allows us to switch between Altera mSGDMA or SoftDMA engines used by
atse(4) device.
This also makes atse(4) driver become 25% smaller.
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9618
SoftDMA is a software implementation of DMA engine built using Altera
FIFO component.
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9620
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
No functional change, only trivial cases are done in this sweep,
Drivers that can get further enhancements will be done independently.
Discussed in: freebsd-current
commit 8bd88585ed
Rework atse_rx_cycles handling: count packets instead of fills, and use the
limit only when polling, not when in interrupt mode. Otherwise, we may
stop reading the FIFO midpacket and clear the event mask even though the
FIFO still has data to read, which could stall receive when a large packet
arrives. Add a comment about races in the Altera FIFO interface: we may
need to do a little more work to handle races than we are.
commit 20b39086cc
Use 'sizeof(data)' rather than '4' when checking an mbuf bound, as is the
case for adjusting length/etc.
commit e18953174a
Break out atse_intr() into two separate routines, one for each of the two
interrupt sources: receive and transmit.
commit 6deedb4324
For the RX interrupt, take interest only in ALMOSTEMPTY and OVERFLOW.
For the TX interrupt, take interest only in ALMOSTFULL and UNDERFLOW.
Perform TX atse_start_locked() once rather than twice in TX interrupt
handling -- and only if !FULL, rather than unconditionally.
commit 12601972ba
Experimentation suggests that the Altera Triple-Speed Ethernet documentation
is incorrect and bits in the event and interrupt-enable registers are not
irrationally rearranged relative to the status register.
commit 3cff2ffad7
Substantially rework interrupt handling in the atse(4) driver:
- Introduce a new macro ATSE_TX_PENDING() which checks whether there is
any pending data to transmit, either in an in-progress packet or in
the TX queue.
- Introduce new ATSE_RX_STATUS_READ() and ATSE_TX_STAUTS_WRITE() macros
that query the FIFO status registers rather than event registers,
offering level- rather than edge-triggered FIFO conditions.
- For RX, interrupt only on full/overflow/underflow; for TX, interrupt
only on empty/overflow/underflow.
- Add new ATSE_RX_INTR_READ() and ATSE_RX_INTR_WRITE() macros useful for
debugging interrupt behaviour.
- Add a debug.atse_intr_debug_enable sysctl that causes various pieces
of FIFO state to be printed out on each RX or TX interrupt. This is
disabled by default but good to turn on if the interface appears to
wedge. Also print debugging information when polling.
- In the watchdog handler, do receive, not just transmit, processing, to
ensure that the rx, not just tx, queue is being handled -- and, in
particular, will be drained such that interrupts can resume.
- Rework both atse_rx_intr() and atse_tx_intr() to eliminate many race
conditions, and add comments on why various things are in various
orders. Interactions between modifications to the event and interrupt
masks are quite subtle indeed, and we must actively check for a number
of races (e.g., event mask cleared; packet arrives; interrupts enabled).
We also now use the status registers rather than event registers for
FIFO status checks to avoid other races; we continue to use event
registers for underflow/overflow.
With this change, interrupt-driven operation of atse appears (for the
time being) robust.
commit 3393bbff5c
atse: Fix build after 3cff2ffa
Obtained from: cheribsd
Submitted by: rwatson, emaste
Sponsored by: DARPA/AFRL
MFC after: 3 days
to check the status property in their probe routines.
Simplebus used to only instantiate its children whose status="okay"
but that was improper behavior, fixed in r261352. Now that it doesn't
check anymore and probes all its children; the children all have to
do the check because really only the children know how to properly
interpret their status property strings.
Right now all existing drivers only understand "okay" versus something-
that's-not-okay, so they all use the new ofw_bus_status_okay() helper.
221804, 221805, 222004, 222006, 222055, 222820, 1135077, 1135118, 1136259
Add atse(4), a driver for the Altera Triple Speed Ethernet MegaCore.
The current driver support gigabit Ethernet speeds only and works with
the MegaCore only in the internal FIFO configuration in the soon to be
open sourced BERI CPU configuration.
Submitted by: bz
MFC after: 3 days
Sponsored by: DARPA/AFRL
