Introduce ATA_CAM kernel option, turning ata(4) controller drivers into
cam(4) interface modules. When enabled, this options deprecates all ata(4)
peripheral drivers (ad, acd, ...) and interfaces and allows cam(4) drivers
(ada, cd, ...) and interfaces to be natively used instead.
As side effect of this, ata(4) mode setting code was completely rewritten
to make controller API more strict and permit above change. While doing
this, SATA revision was separated from PATA mode. It allows DMA-incapable
SATA devices to operate and makes hw.ata.atapi_dma tunable work again.
Also allow ata(4) controller drivers (except some specific or broken ones)
to handle larger data transfers. Previous constraint of 64K was artificial
and is not really required by PCI ATA BM specification or hardware.
Submitted by: nwitehorn (powerpc part)
If you just config KERNEL as usual there should be no apparent changes, you'll get all chipset support code compiled in.
However there is now a way to only compile in code for chipsets needed on a pr vendor basis. ATA now has the following "device" entries:
atacore: ATA core functionality, always needed for any ATA setup
atacard: CARDBUS support
atacbus: PC98 cbus support
ataisa: ISA bus support
atapci: PCI bus support only generic chipset support.
ataahci: AHCI support, also pulled in by some vendor modules.
ataacard, ataacerlabs, ataadaptec, ataamd, ataati, atacenatek, atacypress, atacyrix, atahighpoint, ataintel, ataite, atajmicron, atamarvell, atamicron, atanational, atanetcell, atanvidia, atapromise, ataserverworks, atasiliconimage, atasis, atavia; Vendor support, ie atavia for VIA chipsets
atadisk: ATA disk driver
ataraid: ATA softraid driver
atapicd: ATAPI cd/dvd driver
atapifd: ATAPI floppy/flashdisk driver
atapist: ATAPI tape driver
atausb: ATA<>USB bridge
atapicam: ATA<>CAM bridge
This makes it possible to config a kernel with just VIA chipset support by having the following ATA lines in the kernel config file:
device atacore
device atapci
device atavia
And then you need the atadisk, atapicd etc lines in there just as usual.
If you use ATA as modules loaded at boot there is few changes except the rename of the "ata" module to "atacore", things looks just as usual.
However under atapci you now have a whole bunch of vendor specific drivers, that you can kldload individually depending on you needs. Drivers have the same names as used in the kernel config explained above.
