Deprecation/removal of nios2 target support

[Marek Vasut]

On 4/18/24 7:53 AM, Thomas Huth wrote:
> On 18/04/2024 05.27, Sandra Loosemore wrote:
>> Tomorrow I plan to push patches to mark the nios2 target as obsolete 
>> in GCC 14.
>>
>> Background: Intel has EOL'ed the Nios II processor IP and is now 
>> directing their FPGA customers to a RISC-V platform instead.
>>
>> https://www.intel.com/content/www/us/en/content-details/781327/intel-is-discontinuing-ip-ordering-codes-listed-in-pdn2312-for-nios-ii-ip.html
>>
>> The Nios II hardware on loan from Intel that we were using for testing 
>> at Mentor Graphics/Siemens was returned around the first of the year. 
>> For some time we had been using QEMU to test the nios2-elf target, but 
>> we never had a QEMU test harness set up that would boot the Linux 
>> kernel, and user-mode QEMU on this target is too buggy/unmaintained to 
>> use for primary testing. So the current situation is that none of the 
>> listed maintainers for any of the GNU toolchain components have access 
>> to a fully working test configuration any more, we have all moved on 
>> to new jobs and different projects, Intel has also moved on to a 
>> different platform, and our former contacts on Intel's Nios II team 
>> have moved on as well.  It seems like it's time to pull the plug.
>>
>> Therefore I'd like to mark Nios II as obsolete in GCC 14 now, and 
>> remove support from all toolchain components after the release is 
>> made.  I'm not sure there is an established process for 
>> obsoleting/removing support in other components; besides binutils, 
>> GDB, and GLIBC, there's QEMU, newlib/libgloss, and the Linux kernel.  
>> But, we need to get the ball rolling somewhere.
> 
> Thanks for the heads-up, Sandra! FWIW: QEMU already marked the nios2 
> target as deprecated, too, and plans to remove it in version 9.1 (in 
> autumn this year).

Thank you and sorry for being inactive for so long around nios2.