PCIe can read/write to any 32-bit address using the PCI index/index2
registers as an address and then reading/writing the corresponding
data/data2 register.
This commit adds this functionality and removes one magic value being
written to support GPU POST. This feature is disabled for Vega10 which
relies on an MMIO trace for too many values to implement in the MMIO
interface.
Change-Id: Iacfdd1294a7652fc3e60304b57df536d318c847b
The top level AMDGPUDevice currently reads/writes all unknown registers
to/from a map containing the previously written value. This is intended
as a way to handle registers that are not part of the model but the
driver requires for functionality. Since this is at the top level, it
can mask changes to register values which do not go through the same
interface. For example, reading an MMIO, changing via PM4 queue, and
reading again returns the stale cached value.
This commit removes the usage of the regs map in AMDGPUDevice,
implements some important MMIOs that were previously handled by it, and
moves the unknown register handling to the NBIO aperture only. To reduce
the number of additional MMIOs to implement, the display manager in
vega10 is now disabled.
Change-Id: Iff0a599dd82d663c7e710b79c6ef6d0ad1fc44a2
Currently gem5 assumes the amdgpu device to be Vega10. In order to
support more devices we need to handle situations where different
registers and addresses have the same functionality but different
offsets on different devices.
This changeset adds an NBIO class to handle device discovery and driver
initialization related tasks, pulling them out of the AMDGPUDevice
class. The offsets used for MMIOs are reworked slightly to use offsets
rather than absolute addresses. This is because we cannot determine the
absolute address in the constructor since the BAR has not been assigned
by the OS yet.
Change-Id: I14b364374e086e185978334425a4e265cf2760d0
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/70041
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
