What is TYPE_TPM_TIS_ISA? (Not an ISA Device)

[Philippe Mathieu-Daudé]

Hi Stefan,

I'm trying to understand what is modelling the
TYPE_TPM_TIS_ISA device.

It inherits from TYPE_ISA_DEVICE, so I expected
to see an ISA device, but then I noticed:

1/ it doesn't use the ISA I/O space, it directly
maps the device in the system memory at a fixed
address that is not addressable by the ISA bus:

#define TPM_TIS_ADDR_BASE           0xFED40000

2/ it is not plugged to an ISA BUS (ISABus*)

3/ no machine plug it using isa_register_ioport()
   (it is not registered to the ISA memory space)

4/ the only thing slightly related to ISA is it
checks the IRQ number is < ISA_NUM_IRQS


So it seems this is a plain SysBusDevice. But then
there is TYPE_TPM_TIS_SYSBUS... What is the difference?

Thanks,

Phil.