freebsd with flexible iflib nic queues
789902c3ae
by a transaction performing a driver handled message sequence (an scb with the MK_MESSAGE flag set). SCBs that perform host managed messaging must always be at the head of their per-target selection queue so that the firmware knows to manually assert ATN if the current negotiation agreement is packetized. In the past we guaranteed this by queuing these SCBs separarately in the execution queue. This exposes the system to potential command reordering in two cases: 1) Another SCB for the same ITL nexus is queued that does not have the MK_MESSAGE flag set. This SCB will be queued to the per-target list which can be serviced before the MK_MESSAGE scb that preceeded it. 2) If the target cannot accept all of the commands in the per-target selection queue in one selection, the remainder is queued to the tail of the selection queues so as to effect round-robin scheduling. This could allow the MK_MESSAGE scb to be sent to the target before the requeued commands. This commit changes the firmware policy to defer queuing MK_MESSAGE SCBs into the selection queues until this can be done without affecting order. This means that the target's selection queue is either empty, or the last SCB on the execution queue is also a MK_MESSAGE SCB. During any wait, the firmware halts the download of new SCBs so only a single "holding location" is required. Luckily, MK_MESSAGE SCBs are rare and typically occur only during CAM's bus probe where only one command is outstanding at a time. However, during some recovery scenarios, the reordering *could* occur. aic79xx.c: Update ahd_search_qinfifo() and helper routines to search for pending MK_MESSAGE scbs and properly restitch the execution queue if either the MK_MESSAGE SCB is being aborted, or the MK_MESSAGE SCB can be queued due to the execution queue draining due to aborts. Enable LQOBUSFREE status to assert an interrupt. This should be redundant since a BUSFREE interrupt should always occur along with an LQOBUSFREE event, but on the Rev A, this doesn't seem to be guaranteed. When a PPR request is rejected when a previously existing packetized agreement is in place, assume that the target has been reset without our knowledge and revert to async/narrow transfers. This corrects two issues: the stale ENATNO setting that was used to send the PPR is cleared so the firmware is not confused by a future packetized selection with ATN asserted but no MK_MESSAGE flag in the SCB and it speeds up recovery by aborting any pending packetized transactions that by definition are now dead. When re-queueing SCBs after a failed negotiation attempt, ensure command ordering by freezing the device queue first. Traverse the list of pending SCBs rather than the whole SCB array on the controller when pushing MK_MESSAGE flag changes out to the controller. The original code was optimized for the aic7xxx controllers where there are fewer controller slots then pending SCBs and the firmware picks SCB slots. For the U320 controller, the hope is that we have fewer pending SCBs then the 512 slots on the controller. Enhance some diagnostics. Factor out some common code. aic79xx.h: Add prototype for new ahd_done_with_status() that is used to factor out some commone code. aic79xx.reg: Add definisions for the pending MK_MESSAGE SCB. aic79xx.seq: Defer MK_MESSAGE SCB queing to the execution queue so as to preserve command ordering. Re-arrange some of the selection processing code so the above change had no performance impact on the common code path. Close a few critical section holes. When entering a non-packetized phase, manually enable busfree interrupts, since the controller hardware does not do this automatically. aic79xx_inline.h: Enhance logging for queued SCBs. aic79xx_osm.c: Add new a new DDB ahd command, ahd_dump, which invokes the ahd_dump_card_state() routine on the unit specified with the ahd_sunit DDB command. aic79xx_pci.c: Turn on the BUSFREEREV bug for the Rev B. controller. This is required to close the busfree during non-packetized phase hole. |
||
|---|---|---|
| bin | ||
| contrib | ||
| crypto | ||
| etc | ||
| games | ||
| gnu | ||
| include | ||
| kerberos5 | ||
| lib | ||
| libexec | ||
| release | ||
| rescue | ||
| sbin | ||
| secure | ||
| share | ||
| sys | ||
| tools | ||
| usr.bin | ||
| usr.sbin | ||
| COPYRIGHT | ||
| installworld_newk | ||
| installworld_oldk | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc1 | ||
| README | ||
| UPDATING | ||
| UPDATING.64BTT | ||
This is the top level of the FreeBSD source directory. This file was last revised on: $FreeBSD$ For copyright information, please see the file COPYRIGHT in this directory (additional copyright information also exists for some sources in this tree - please see the specific source directories for more information). The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree, the most commonly used one being ``world'', which rebuilds and installs everything in the FreeBSD system from the source tree except the kernel, the kernel-modules and the contents of /etc. The ``buildkernel'' and ``installkernel'' targets build and install the kernel and the modules (see below). Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel is a somewhat more involved process, documentation for which can be found at: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html And in the config(8) man page. Note: If you want to build and install the kernel with the ``buildkernel'' and ``installkernel'' targets, you might need to build world before. More information is available in the handbook. The sample kernel configuration files reside in the sys/<arch>/conf sub-directory (assuming that you've installed the kernel sources), the file named GENERIC being the one used to build your initial installation kernel. The file NOTES contains entries and documentation for all possible devices, not just those commonly used. It is the successor of the ancient LINT file, but in contrast to LINT, it is not buildable as a kernel but a pure reference and documentation file. Source Roadmap: --------------- bin System/user commands. contrib Packages contributed by 3rd parties. crypto Cryptography stuff (see crypto/README). etc Template files for /etc. games Amusements. gnu Various commands and libraries under the GNU Public License. Please see gnu/COPYING* for more information. include System include files. kerberos5 Kerberos5 (Heimdal) package. lib System libraries. libexec System daemons. release Release building Makefile & associated tools. sbin System commands. secure Cryptographic libraries and commands. share Shared resources. sys Kernel sources. tools Utilities for regression testing and miscellaneous tasks. usr.bin User commands. usr.sbin System administration commands. For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html