freebsd-dev/sys/dev/mly
Scott Long f6b1c44d1f Mega busdma API commit.
Add two new arguments to bus_dma_tag_create(): lockfunc and lockfuncarg.
Lockfunc allows a driver to provide a function for managing its locking
semantics while using busdma.  At the moment, this is used for the
asynchronous busdma_swi and callback mechanism.  Two lockfunc implementations
are provided: busdma_lock_mutex() performs standard mutex operations on the
mutex that is specified from lockfuncarg.  dftl_lock() is a panic
implementation and is defaulted to when NULL, NULL are passed to
bus_dma_tag_create().  The only time that NULL, NULL should ever be used is
when the driver ensures that bus_dmamap_load() will not be deferred.
Drivers that do not provide their own locking can pass
busdma_lock_mutex,&Giant args in order to preserve the former behaviour.

sparc64 and powerpc do not provide real busdma_swi functions, so this is
largely a noop on those platforms.  The busdma_swi on is64 is not properly
locked yet, so warnings will be emitted on this platform when busdma
callback deferrals happen.

If anyone gets panics or warnings from dflt_lock() being called, please
let me know right away.

Reviewed by:	tmm, gibbs
2003-07-01 15:52:06 +00:00
..
mly_tables.h Fix warnings (comment out unused tables that are taking space in the 2002-02-27 23:57:18 +00:00
mly.c Mega busdma API commit. 2003-07-01 15:52:06 +00:00
mlyio.h Merge with latest version of the Mylex 6+ driver. 2001-07-14 00:12:23 +00:00
mlyreg.h use __packed. 2002-09-23 18:54:32 +00:00
mlyvar.h Fix the mly driver! If card resources became unavailable, the driver would 2003-02-06 23:46:32 +00:00