i960 (non-ARM) based
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80960 RM
- primary and secondary PCI bus are 32 bit
- has an application accelerator

80960 RN
- primary and secondary PCI bus are 32/64 bit
- has an application accelerator

80960 RS
- primary and secondary PCI bus are 32 bit
- does not have an application accelerator


xscale (ARM) based, separate cpu and 'northbridge'
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80200 processor
- 80200 is an xscale with icache/dcache, programmable pll, minimal
  interrupt 'controller', bus interface unit
- interrupt 'controller' on cp13
	INTCTL: CP13 reg 0: BCU/PMU/IRQ#/FIQ# mask

80312 I/O companion ('northbridge') chip
- connects one 80200, has two 66/64 pci buses, sdram controller, 2 ATUs,
  DMA, I2C, I2O, XOR accelerator, perf monitor, 8 GPIOs.
- combination of 80200 + 80312 is called "80310 [I/O] processor chipset"

80314 I/O companion ('northbridge') chip
- connects to up to two 80200s, has two PCI-X ports, two gigabit
  ethernet ports, sdram controller, interrupt controller, two 8250
  UARTs, two i2c ports, 1 MB static RAM.
- combination of 80200 + 80314 is called "IOP315 chipset"


xscale (ARM) based, cpu + northbridge integrated on one chip
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80219 pci processor (80321 without sync serial and application accelerator)
- xscale core
- address translation unit
- memory controller
- peripheral bus interface (single 64/32 pci bus)
- i2c bus interface units (2)
- dma controller (2 channels)
- performance monitoring unit
- messaging unit
- i2o compatibility


80321 chip
- xscale core
- address translation unit
- memory controller
- peripheral bus interface (single 64/32 pci bus)
- application accelerator
- i2c bus interface units (2)
- dma controller (2 channels)
- performance monitoring unit
- synchronous serial port unit
- messaging unit
- i2o compatibility
- 8 GPIOs
- CP6: interrupt controller / timers
- CP7: bus interface unit
- physical memory typically at a000_0000


80331 i/o processor
- xscale core
- pci interface with ATU
- physical memory typically at 00000000


80332 i/o processor
- xscale core
- 32/64 bit DDR sdram controller
- UARTs
- 2x i2c
- PBI
- application accelerator
- interrupt/gpio
- 2-chan DMA
- timers
- ATU/message unit
- PMU
- 2x pci-x 133MHz, 1x PCI-E x8
- 2x IOAPIC

80333 i/o processor
- same as 80332, plus smbus?