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

[Andrew Donnellan]

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?

Maybe we should generalise the EXTRACT_BITS macro we use in ocxl :)

--
Andrew Donnellan              OzLabs, ADL Canberra
ajd@xxxxxxxxxxxxx             IBM Australia Limited