Dan Williams wrote:
> In preparation for region autodiscovery, that needs all devices
> discovered before their relative position in the region can be
> determined, consolidate all position dependent validation in a helper.
>
> Recall that in the on-demand region creation flow the end-user picks the
> position of a given endpoint decoder in a region. In the autodiscovery
> case the position of an endpoint decoder can only be determined after
> all other endpoint decoders that claim to decode the region's address
> range have been enumerated and attached. So, in the autodiscovery case
> endpoint decoders may be attached before their relative position is
> known. Once all decoders arrive, then positions can be determined and
> validated with cxl_region_validate_position() the same as user initiated
> on-demand creation.
>
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> ---
> drivers/cxl/core/region.c | 119 +++++++++++++++++++++++++++++----------------
> 1 file changed, 76 insertions(+), 43 deletions(-)
>
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 97eafdd75675..c82d3b6f3d1f 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -1207,35 +1207,13 @@ static int cxl_region_setup_targets(struct cxl_region *cxlr)
> return 0;
> }
>
[snip]
> @@ -1274,6 +1252,71 @@ static int cxl_region_attach(struct cxl_region *cxlr,
> }
> }
>
> + return 0;
> +}
> +
> +static int cxl_region_attach_position(struct cxl_region *cxlr,
> + struct cxl_root_decoder *cxlrd,
> + struct cxl_endpoint_decoder *cxled,
> + const struct cxl_dport *dport, int pos)
> +{
> + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
> + struct cxl_port *iter;
> + int rc;
> +
> + if (cxlrd->calc_hb(cxlrd, pos) != dport) {
> + dev_dbg(&cxlr->dev, "%s:%s invalid target position for %s\n",
> + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
> + dev_name(&cxlrd->cxlsd.cxld.dev));
> + return -ENXIO;
> + }
I think I know the answer but I'm curious why this check is not part of
validating the position? Is it because this is validating the position
relative to the hostbridge which is not strictly part of the region
validation?
Ira
