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What is TYPE_TPM_TIS_ISA? (Not an ISA Device)
From: |
Philippe Mathieu-Daudé |
Subject: |
What is TYPE_TPM_TIS_ISA? (Not an ISA Device) |
Date: |
Tue, 21 Jul 2020 18:02:56 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 |
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.
- What is TYPE_TPM_TIS_ISA? (Not an ISA Device),
Philippe Mathieu-Daudé <=