The busdma interfaces permit hardware device drivers to operate on a variety of platforms avoiding the encoding of platform-specific access methods into drivers. This lowers the maintenance costs for drivers across platforms, and improves the chances that a driver will "just work" on a new platform. Modifying a driver to make use of busdma is relatively straight forward, but does require familiarity with both the device driver and busdma primitives. For busdma to be used in FreeBSD, two sets of changes are generally required: adaptation of the busdma implementation to run on all platforms, and adaptation of drivers to use the framework. As such, status information on this project is broken down into platform support, and driver support (sorted by category). Completing this work requires a thorough audit of the system device drivers, then prioritized conversion of drivers.
The task list below is not intended to be complete, but does represent a set of relevant and/or important components of the overall work. The "Responsible" field identifies a developer who has expressed willingness to be responsible for completing the identified task; this doesn't preclude others working on it, but suggests that coordination with the responsible party might be appropriate so as to avoid unnecessary duplication of work, and to maximize forward progress. If beginning work on a new area of substantial size, or one that appears unclaimed, it may be worth dropping an e-mail to &a.mux; to see if any progress has been made.
The definition of the date field varies depending on the status of a task. For completed tasks, it refers to the date completed or reported completed. For in-progress tasks, it refers to the date of the last update of the entry. For stalled tasks, it refers to the date that the task was declared stalled. For new tasks, it refers to the date the task was added to the list.
Tasks are sorted first by status, then by date.
| Task | Responsible | Last updated | Status | Details |
|---|---|---|---|---|
| alpha | &a.gallatin; | December 10, 2002 | &status.wip; | Support for mbuf and uio load routines present, but untested. Pending availability of mainstream network interface drivers to perform testing. In addition, there may be problems with large amounts of memory. |
| ia64 | &a.marcel; | December 10, 2002 | &status.wip; | All the primitives are in place, but network interface drivers are required for testing the mbuf and uio load routines. In addition, there may be problems for systems with large amounts of memory. |
| i386 | &a.sam; | December 9, 2002 | &status.done; | Fully supported. |
| powerpc | &a.grehan; | December 10, 2002 | &status.wip; | No support for bus_dmamap_load_mbuf() or bus_dmamap_load_uio() yet. |
| sparc64 | &a.tmm; | December 9, 2002 | &status.wip; | No support for bus_dmamap_load_mbuf() or bus_dmamap_load_uio() yet. |
| Task | Responsible | Last updated | Status | Notes |
|---|---|---|---|---|
| if_ar | &status.new; | kvtop() | ||
| if_bge | &status.new; | vtophys() | ||
| if_cs | &status.new; | |||
| if_dc | &status.new; | vtophys() | ||
| if_ed | &status.new; | kvtop() | ||
| if_em | &status.new; | vtophys() | ||
| if_en | &status.new; | vtophys() | ||
| if_fxp | &a.mux; | December 9, 2002 | &status.wip; | vtophys() |
| if_fwe | &status.new; | |||
| if_gem | &a.tmm; | December 9, 2002 | &status.wip; | Uses old busdma interface. |
| if_gx | &status.new; | vtophys() | ||
| if_hme | &a.tmm; | December 9, 2002 | &status.wip; | Uses old busdma interface. |
| if_idt | &status.new; | vtophys() | ||
| if_ie | &status.new; | kvtop() | ||
| if_lge | &status.new; | vtophys() | ||
| if_lmc | &status.new; | vtophys() | ||
| if_lnc | &status.new; | vtophys() | ||
| if_mn | &status.new; | vtophys() | ||
| if_my | &status.new; | vtophys() | ||
| if_nge | &status.new; | vtophys() | ||
| if_pcn | &status.new; | vtophys() | ||
| if_pdq | &status.new; | mostly busdma, except for vtophys() | ||
| if_rl | &a.wpaul; | December 9, 2002 | &status.done; | |
| if_sf | &status.new; | vtophys() | ||
| if_sis | &a.wpaul; | December 9, 2002 | &status.done; | |
| if_sk | &status.new; | vtophys() | ||
| if_sr | &status.new; | vtophys() | ||
| if_ste | &status.new; | vtophys() | ||
| if_ti | &status.new; | |||
| if_tl | &status.new; | |||
| if_tx | &status.new; | |||
| if_txp | &status.new; | |||
| if_vr | &status.new; | |||
| if_wb | &status.new; | |||
| if_xl | &a.mux; | December 9, 2002 | &status.wip; | Patches are now available, and they seem to work on x86. Some more testing needs to be done, especially for other architectures. |
| Task | Responsible | Last updated | Status | Notes | ||||
|---|---|---|---|---|---|---|---|---|
| aac | December 9, 2002 | &status.done; | Not 64-bit-safe | |||||
| aha | December 9, 2002 | &status.done; | ||||||
| adv | December 9, 2002 | &status.done; | ||||||
| ahb | December 9, 2002 | &status.done; | ||||||
| aic7xxx | December 9, 2002 | &status.done; | ||||||
| amd | -&a.scottl; | -December 10, 2002 | -&status.wip; | -vtophys() | ++ | December 14, 2002 | +&status.done; | +|
| amr | December 9, 2002 | &status.done; | ||||||
| asr | &status.new; | vtophys() | ||||||
| ata | December 9, 2002 | &status.done; | ||||||
| buslogic | &status.new; | vtophys() | ||||||
| ciss | December 9, 2002 | &status.done; | ||||||
| ct | &status.new; | |||||||
| dpt | &status.new; | vtophys() | ||||||
| ida | December 9, 2002 | &status.done; | ||||||
| iir | &status.new; | vtophys() | ||||||
| isp | December 9, 2002 | &status.done; | ||||||
| mlx | December 9, 2002 | &status.done; | ||||||
| mly | December 9, 2002 | &status.done; | ||||||
| mpt | December 9, 2002 | &status.done; | ||||||
| ncr | &status.new; | vtophys() | ||||||
| pst | &status.new; | vtophys() | ||||||
| stg | December 9, 2002 | &status.done; | At least, it looks like it may well be. | |||||
| sym | &status.new; | vtophys() | ||||||
| trm | &a.cognet; | December 9, 2002 | &status.wip; | vtophys() | ||||
| twe | December 9, 2002 | &status.done; |
| Task | Responsible | Last updated | Status | Notes |
|---|---|---|---|---|
| agp | &status.done; | vtophys() | ||
| bktr | &status.new; | vtophys() | ||
| cs | &status.new; | |||
| digi | &status.new; | vtophys() | ||
| drm | &status.new; | vtophys() | ||
| exca | &a.imp; | December 9, 2002 | &status.done; | |
| fb | &status.new; | vtophys() | ||
| firewire | &status.new; | vtophys() | ||
| hea | &status.new; | vtophys() | ||
| hfa | &status.new; | vtophys() | ||
| hifn | &a.sam; | December 9, 2002 | &status.done; | |
| meteor | &status.new; | vtophys() | ||
| musycc | &status.new; | vtophys() | ||
| ubsec | &a.sam; | December 9, 2002 | &status.done; | vtophys() is used in debugging printf |
| usb | &a.joe; | December 10, 2002 | &status.new; | vtophys() |
| wds | December 9, 2002 | &status.done; | vtophys() |