ARM has previously shut down open source software emulation of parts of the ARM ISA.
For a while QEMU could not implement ARMv7 I think, until changed their mind and started permitting it. There was an open source processor design on opencores.org that got pulled too.
The reasoning was something like "to implement these instructions you must have read the ARM documentation, which is only available under a license which prohibits certain things in exchange for reading it".
ARM has previously shut down open source software emulation of parts of the ARM ISA.
For a while QEMU could not implement ARMv7 I think, until changed their mind and started permitting it. There was an open source processor design on opencores.org that got pulled too.
The reasoning was something like "to implement these instructions you must have read the ARM documentation, which is only available under a license which prohibits certain things in exchange for reading it".