Marius Strobl eb811915d2 - According to Linux, the ALi M5451 can do 31-bit DMA instead of just
30-bit like the reset of the controllers supported by this driver.
  Actually ALi M5451 can be setup up to generate 32-bit addresses by
  setting the 31st bit via the accompanying ISA bridge, which allows
  it to work in sparc64 machines whose IOMMU require at least 32-bit
  DMA. Even though other architectures would also benefit from 32-bit
  DMA, enabling this bit is limited to sparc64 as bus_dma(9) doesn't
  generally guarantee that a low address of BUS_SPACE_MAXADDR_32BIT
  results in a buffer in the 32-bit range.
- According to Tatsuo YOKOGAWA's ali(4), the the DMA transfer size of
  ALi M5451 is fixed to 64k and in fact using the default size of 4k
- The 4DWAVE DX and NX require the recording buffer to be 8-byte
  aligned so adjust the bus_dma_tag_create(9) accordingly.
- Unlike the rest of the controllers supported by this driver, the
  ALi M5451 only has 32 hardware channels instead of 64 so limit the
  loop in tr_intr() accordingly. [1]

Submitted by:	yongari [1]
Reviewed by:	yongari (superset of what is committed)
MFC after:	3 days
2009-09-22 11:38:45 +00:00
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