Commit d6879d8c authored by Robert Richter's avatar Robert Richter Committed by Dave Jiang
Browse files

cxl/region: Add function to find a port's switch decoder by range 



Factor out code to find the switch decoder of a port for a specific
address range. Reuse the code to search a root decoder, create the
function cxl_port_find_switch_decoder() and rework
match_root_decoder_by_range() to be usable for switch decoders too.

Signed-off-by: default avatarRobert Richter <rrichter@amd.com>
Reviewed-by: default avatarGregory Price <gourry@gourry.net>
Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: default avatarDave Jiang <dave.jiang@intel.com>
Reviewed-by: default avatar"Fabio M. De Francesco" <fabio.m.de.francesco@linux.intel.com>
Tested-by: default avatarGregory Price <gourry@gourry.net>
Acked-by: default avatarDan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20250509150700.2817697-12-rrichter@amd.com


Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
parent 868a8f1f

drivers/cxl/core/region.c

+18 −12
Original line number Diff line number Diff line
@@ -3202,33 +3202,39 @@ static int devm_cxl_add_dax_region(struct cxl_region *cxlr) 
	return rc;

}



static int match_root_decoder_by_range(struct device *dev,

				       const void *data)

static int match_decoder_by_range(struct device *dev, const void *data)

{

	const struct range *r1, *r2 = data;

	struct cxl_root_decoder *cxlrd;

	struct cxl_decoder *cxld;



	if (!is_root_decoder(dev))

	if (!is_switch_decoder(dev))

		return 0;



	cxlrd = to_cxl_root_decoder(dev);

	r1 = &cxlrd->cxlsd.cxld.hpa_range;

	cxld = to_cxl_decoder(dev);

	r1 = &cxld->hpa_range;

	return range_contains(r1, r2);

}



static struct cxl_decoder *

cxl_port_find_switch_decoder(struct cxl_port *port, struct range *hpa)

{

	struct device *cxld_dev = device_find_child(&port->dev, hpa,

						    match_decoder_by_range);



	return cxld_dev ? to_cxl_decoder(cxld_dev) : NULL;

}



static struct cxl_root_decoder *

cxl_find_root_decoder(struct cxl_endpoint_decoder *cxled)

{

	struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);

	struct cxl_port *port = cxled_to_port(cxled);

	struct cxl_root *cxl_root __free(put_cxl_root) = find_cxl_root(port);

	struct cxl_decoder *cxld = &cxled->cxld;

	struct cxl_decoder *root, *cxld = &cxled->cxld;

	struct range *hpa = &cxld->hpa_range;

	struct device *cxlrd_dev;



	cxlrd_dev = device_find_child(&cxl_root->port.dev, hpa,

				      match_root_decoder_by_range);

	if (!cxlrd_dev) {

	root = cxl_port_find_switch_decoder(&cxl_root->port, hpa);

	if (!root) {

		dev_err(cxlmd->dev.parent,

			"%s:%s no CXL window for range %#llx:%#llx\n",

			dev_name(&cxlmd->dev), dev_name(&cxld->dev),
@@ -3236,7 +3242,7 @@ cxl_find_root_decoder(struct cxl_endpoint_decoder *cxled) 
		return NULL;

	}



	return to_cxl_root_decoder(cxlrd_dev);

	return to_cxl_root_decoder(&root->dev);

}



static int match_region_by_range(struct device *dev, const void *data)