* When we are transferring in DATA (in asc_dma_in) and the target
is an async device, there is sometimes an extra byte in the FIFO.
If so, we need to drain that byte out of the fifo, but if and only
if the target is async. See also the comments in asc_dma_in()
in the related Mach mk84 asc driver (scsi_53C94_hdw.c), which
has an identical fix but applied in more restrictive conditions
than we need, with async *disk* targets, as well as async tapes.
* Add a watchdog and timeout active SCSI requests, to eliminate any
potential for deadlock due to applying the fix above on newer
silicon versions of the 53c94 which may not have the above problem.
Should use the MI scsi per-target timeout instead, when available.
cfattach code for TC SCSI option cards and ioasic 53c94 baseboard SCSI.
ascvar.h: shared softc declarations
asc_ioasic.c: ioasic front-end code.
asc_tc.c: Turbochannel option (and 5000/200 basebard) front-end code.
* ioasic_attach meeds more work to eliminate pmax_type dependency
and to verify the clocks speed passed to 53c94.
* Add prototypes for asc script entry points; should compile with
-Wstrict-prototypes -Wmissing-prototypes.
* Use tcvar.h interface. The usage of tc_syncbus() and tc_mb() may
not be quite stylistically on an Alhpa, but it apparently makes no
difference on the eerly-generation Alpha CPUs in TC Alphas.
if the version is <= SCSI-2. This should help some older SCSI
devices that previously needed the "NOLUNS" quirk. While this is
not strictly necessary on SCSI-2 devices, the spec allows it,
so we set it for SCSI-2 devices "just in case". See section 7.2.2 of
Draft X3T9.2 Rev 10L for details.
multi-channel driver), or to SCSI_CHANNEL_ONLY_ONE if a
single-channel driver.
(2) use scsiprint() rather than a locally-defined autoconfig print
function, and kill any locally-defined print function.
(2) in scsibusmatch, match channel as appropriate.
(3) add a scsiprint() function, to do the "scsibus at..."
and channel (if not SCSI_CHANNEL_ONLY_ONE) printing,
i.e. the common functionality that all SCSI drivers currently
should be doing.
a char *, because that's what was really intended, and because
if the print function modifies the string, various things could become
unhappy (so the string should _not_ be modified).
Fix so that resource wait queueing works.
Changed all functions to take a pointer to uba_softc instead of unit
number, except for ubareset(). This must be done later.
the lowest bit set. This isn't any more or less valid according to the PCI
spec, but it deals with lame devices that don't implement all of the top
bits.
a boot string for firmware that can do this, such as the SPARC and
the sun3 models. It is currently silently ignored on all other
hardware now, however. The MD function "boot()" has been changed to
also take a char *.
values, i.e. 0xfffffffe and 0xffffffff respectively. The changed
definitions were incorrect, according to the PCI Local Bus Specification
(Revision 2.0). Further rationale and a workaround for the broken
devices that instigated the change provided in a message to
current-users@netbsd.org, dated Mon, 05 Aug 1996 22:06:58 -0400,
message ID 16773.839297218@ux2.sp.cs.cmu.edu>.
- In egstart(), if the Send Packet command fails, m_freem()
the mbuf chain before dequeueing another one (memory leak).
- In egintr(), return 1 if a known interrupt was processed.
Would manifest itself as spurious interrupts.
- adjust txhiwat and mindma params a bit
- fixed a couple of incorrectly labeled panic calls
- the "location" was being calculated incorrectly in some cases (forgot
to subtract off MID_RAMBASE). this only caused problem when trying
to change the size of the tx/rx buffers (e.g. to 64KB).
- fixed possible non-aligned DMA burst in the starting byte burst case.
(e.g. if we could DMA 3 bytes, but only have 2 it is not legal
for us to use MIDDMA_BYTE2 mode).
- opt: on tx: try and avoid flushing the internal buffer by padding out the
length of the last mbuf a bit (if possible)
- merged multiple DRQ/DTQ ADD macros into a single DRQ and a single DTQ
macro with a uniform interface to make the code simpler and easier to read.
- en_start: only update atm_flags if EN_MBUF_OPT is enabled (which it
should be)
- for alburst: make sure we don't DMA more bytes than we need (on both
tx and rx). if the alburst is larger than we need, drop to
MIDDMA_WORD mode.
- major change: enable the use of byte and 2 byte DMA on the trasmit side.
this allows us to DMA from non-word sized/aligned mbufs directly.
[the old code would always call en_mfix which would copy (or move) the
data in order to ensure proper alignment... it turns out TCP gives
us non-word sized/aligned mbufs when it is retransmitting, so we needed
to handle this case more efficiently.] the following functions
were changed to make this work:
- en_dqneed: add an arg to let us know if we are transmitting or not.
if we are TX, then we must take into account byte DMAs when
estimating the number of DTQs we will need for a buffer
- en_start: only mfix mbufs if DMA is disabled
- en_txdma: only set launch.nodma if we have en_mfix'd the mbuf chain
also, we may need a DTQ to flush the chip's internal byte buffer
- en_txlaunch: only attempt a copy if we have the proper alignment.
add byte dma code for the front and end of the buffer.
make sure the internal dma buffer is flushed out.
- stats: keep track of how many times we have to use byte sized DMA
midwayreg:
- add byte/2byte DMA defines
midwayvar:
- add new stat counter to monitor less-than-word lengthed DMA
2441, and part of 2600. 2436 is left open to remind me that Chris's
comments are probably correct. This file should be built statically and
committed to the tree, not built on a per-kernel basis.
string with 0xFF instead of 0x20. Shorten the compare to 6 bytes to
take care of this.
Fixes PR #2617 by myself, which is based on a private problem report
by Neil Brewitt.
- en_mfix shouldn't touch M_EXT mbufs. change to avoid this [at
the expense of allocating a new cluster mbuf to copy to].
XXX: en_mfix is getting called more often than I hoped it would
(seems to happen when TCP retransmits... we get all sorts of odd
sized, odd lengthed data mbufs, yuck). i may revise the xmit
DMA code to use non-word sized dma.
- don't try and add a PDU trailer (or TBD for that matter) to an M_EXT
mbuf. when M_EXT is set, the data area of the mbuf can be shared
with other mbufs (see m_copym()), and writing to one M_EXT mbuf may
invalidate another M_EXT mbuf (saw this with PDU trailers).
- be sure to validate the length value from the PDU trailer so that it
doesn't throw us out of sync with the chip (fixes yet another source
of the dread "en_service: id mismatch" panic).
- on recv, don't bother allocating an mbuf if mlen is zero since we are
only going to toss the data anyway.
