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
- Work around a problem not yet solved in the tree (but solved in mine.)
device_get_ivars() should never be cast to a struct resource_list *
The solution, under review, involves the creation of a
device_get_resource_list() function. More later.
MCA SCSI adapters.
bt_mca.c is going to live in sys/dev/buslogic instead of sys/dev/mca
as per a conversation with Peter, Doug and Mike.
Thanks to Andy Farkas <andyf@speednet.com.au> for being such a good
sport and doing all the testing for me (as I don't actually own one
of these cards. Yet.)
