Re: [PATCH v3 13/27] powerpc/powernv/pmem: Read the capability registers & wait for device ready

From: Alastair D'Silva
Date: Wed Feb 26 2020 - 22:58:36 EST


On Thu, 2020-02-27 at 14:54 +1100, Andrew Donnellan wrote:
> On 21/2/20 2:27 pm, Alastair D'Silva wrote:
> > +/**
> > + * read_device_metadata() - Retrieve config information from the
> > AFU and save it for future use
> > + * @ocxlpmem: the device metadata
> > + * Return: 0 on success, negative on failure
> > + */
> > +static int read_device_metadata(struct ocxlpmem *ocxlpmem)
> > +{
> > + u64 val;
> > + int rc;
> > +
> > + rc = ocxl_global_mmio_read64(ocxlpmem->ocxl_afu,
> > GLOBAL_MMIO_CCAP0,
> > + OCXL_LITTLE_ENDIAN, &val);
> > + if (rc)
> > + return rc;
> > +
> > + ocxlpmem->scm_revision = val & 0xFFFF;
> > + ocxlpmem->read_latency = (val >> 32) & 0xFF;
>
> This field is 16 bits in the spec, so the mask should be 0xFFFF I
> think?
>

You're right, I'll fix it.

> Maybe we should generalise the EXTRACT_BITS macro we use in ocxl :)
>
--
Alastair D'Silva
Open Source Developer
Linux Technology Centre, IBM Australia
mob: 0423 762 819