1.. _opal_nx_coproc_init:
2
3OPAL_NX_COPROC_INIT
4===================
5
6This OPAL call resets read offset and queued entries in high and normal
7priority receive FIFO control registers. The kernel initializes read
8offset entry in RXFIFO that it maintains during initialization. So this
9register reset is needed for NX module reload or in kexec boot to make sure
10read offset value matches with kernel entries. Otherwise NX reads requests
11with wrong offset in RxFIFO which could cause NX request failures.
12
13The kernel initiates this call for each coprocessor type such as 842 and
14GZIP per NX instance.
15
16Arguments
17---------
18::
19
20  ``uint32_t chip_id``
21    Contains value of the chip number identified at boot time.
22
23  ``uint32_t pid``
24    Contains NX coprocessor type (pid from the device tree).
25
26Returns
27-------
28OPAL_SUCCESS
29  The call to reset readOffset and queued entries for high and normal
30  FIFOs was successful.
31
32OPAL_PARAMETER
33  Indicates invalid chip ID or NX coprocessor type.
34
35OPAL_UNSUPPORTED
36  Not supported on P7 and P8.
37