[Skiboot] [PATCH V3] NX: Add NX coprocessor init opal call

[Stewart Smith]

Haren Myneni <haren at linux.vnet.ibm.com> writes:
> The read offset (4:11) in Receive FIFO control register is incremented
> by FIFO size whenever CRB read by NX. But the index in RxFIFO has to
> match with the corresponding entry in FIFO maintained by VAS in kernel.
> VAS entry is reset to 0 when opening the receive window during driver
> initialization. So when NX842 is reloaded or in kexec boot, possibility
> of mismatch between RxFIFO control register and VAS entries in kernel.
> It could cause CRB failure / timeout from NX.
>
> This patch adds nx_coproc_init opal call for kernel to initialize
> readOffset (4:11) and Queued (15:23) in RxFIFO control register.
>
> Fixes: 3b3c5962f432 ("NX: Add P9 NX support for 842 compression engine")
> CC: stable # v5.8+
> Signed-off-by: Haren Myneni <haren at us.ibm.com>
> ---
> Changelog:
> v2: Added doc/opal-api/opal_nx_coproc_init-167.rst
>
> v3: Format changes and corrections in opal_nx_coproc_init-167.rst
>     Return unsupported on P7 and P8

Thanks. Merged to master as of 56026a13292453b072ad3cc9adf3dee960077f38
and cherry-picked to 6.0.x as of e4f0860c4372786f7fe959e7a7807740e68dc9d3

-- 
Stewart Smith
OPAL Architect, IBM.