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
Through the PITA of endiannness, clock has to be MHz freq << 8.
Don't trust NVRAM on SBus cards.
Set a default initiator ID sensibly.
SBus/ISP now working, what with the change to sbus.c earlier today.
flags include INTR_MPSAFE. Put the flags in a common place so that
both isp_sbus && isp_pci DTRT.
In isp_mbxdma setup, drop any locks prior to calling things like
bus_dmatag_create. This gets rid of these obnoxious WITNESS messages
about 'sleeping with locks held' blah blah blah blah blah.
This code does not imply that SBus cards work yet. They hang for me.
But I can't netboot the latest snapshot on my ultra1e, and things
hang at bus_setup_intr time.
Since I'm offline for a while, I thought I'd toss this in in case somebody
else who has a bit better luck wants to fart around with it. Please try
and wait until I get back to check things in.
