Commit 4fe82279 authored by Robert Richter's avatar Robert Richter Committed by Dave Jiang
Browse files

cxl/region: Store root decoder in struct cxl_region 



A region is always bound to a root decoder. The region's associated
root decoder is often needed. Add it to struct cxl_region.

This simplifies the code by removing dynamic lookups and the root
decoder argument from the function argument list where possible.

Patch is a prerequisite to implement address translation which uses
struct cxl_region to store all relevant region and interleaving
parameters. It changes the argument list of __construct_region() in
preparation of adding a context argument. Additionally the arg list of
cxl_region_attach_position() is simplified and the use of
to_cxl_root_decoder() removed, which always reconstructs and checks
the pointer. The pointer never changes and is frequently used. Code
becomes more readable as this amphazises the binding between both
objects.

Reviewed-by: default avatarDave Jiang <dave.jiang@intel.com>
Reviewed-by: default avatarJonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: default avatarGregory Price <gourry@gourry.net>
Reviewed-by: default avatarAlison Schofield <alison.schofield@intel.com>
Signed-off-by: default avatarRobert Richter <rrichter@amd.com>
Link: https://patch.msgid.link/20260114164837.1076338-3-rrichter@amd.com


Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
parent df8b57c3

drivers/cxl/core/region.c

+19 −18
Original line number Diff line number Diff line
@@ -489,9 +489,9 @@ static ssize_t interleave_ways_store(struct device *dev, 
				     struct device_attribute *attr,

				     const char *buf, size_t len)

{

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev->parent);

	struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld;

	struct cxl_region *cxlr = to_cxl_region(dev);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld;

	struct cxl_region_params *p = &cxlr->params;

	unsigned int val, save;

	int rc;
@@ -552,9 +552,9 @@ static ssize_t interleave_granularity_store(struct device *dev, 
					    struct device_attribute *attr,

					    const char *buf, size_t len)

{

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev->parent);

	struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld;

	struct cxl_region *cxlr = to_cxl_region(dev);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld;

	struct cxl_region_params *p = &cxlr->params;

	int rc, val;

	u16 ig;
@@ -628,7 +628,7 @@ static DEVICE_ATTR_RO(mode); 


static int alloc_hpa(struct cxl_region *cxlr, resource_size_t size)

{

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_region_params *p = &cxlr->params;

	struct resource *res;

	u64 remainder = 0;
@@ -1373,7 +1373,7 @@ static int cxl_port_setup_targets(struct cxl_port *port, 
				  struct cxl_region *cxlr,

				  struct cxl_endpoint_decoder *cxled)

{

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	int parent_iw, parent_ig, ig, iw, rc, pos = cxled->pos;

	struct cxl_port *parent_port = to_cxl_port(port->dev.parent);

	struct cxl_region_ref *cxl_rr = cxl_rr_load(port, cxlr);
@@ -1731,10 +1731,10 @@ static int cxl_region_validate_position(struct cxl_region *cxlr, 
}



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_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);

	struct cxl_switch_decoder *cxlsd = &cxlrd->cxlsd;

	struct cxl_decoder *cxld = &cxlsd->cxld;
@@ -1971,7 +1971,7 @@ static int cxl_region_sort_targets(struct cxl_region *cxlr) 
static int cxl_region_attach(struct cxl_region *cxlr,

			     struct cxl_endpoint_decoder *cxled, int pos)

{

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);

	struct cxl_dev_state *cxlds = cxlmd->cxlds;

	struct cxl_region_params *p = &cxlr->params;
@@ -2076,8 +2076,7 @@ static int cxl_region_attach(struct cxl_region *cxlr, 
			ep_port = cxled_to_port(cxled);

			dport = cxl_find_dport_by_dev(root_port,

						      ep_port->host_bridge);

			rc = cxl_region_attach_position(cxlr, cxlrd, cxled,

							dport, i);

			rc = cxl_region_attach_position(cxlr, cxled, dport, i);

			if (rc)

				return rc;

		}
@@ -2100,7 +2099,7 @@ static int cxl_region_attach(struct cxl_region *cxlr, 
	if (rc)

		return rc;



	rc = cxl_region_attach_position(cxlr, cxlrd, cxled, dport, pos);

	rc = cxl_region_attach_position(cxlr, cxled, dport, pos);

	if (rc)

		return rc;
@@ -2396,8 +2395,8 @@ static const struct attribute_group *region_groups[] = { 


static void cxl_region_release(struct device *dev)

{

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev->parent);

	struct cxl_region *cxlr = to_cxl_region(dev);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	int id = atomic_read(&cxlrd->region_id);



	/*
@@ -2480,10 +2479,12 @@ static struct cxl_region *cxl_region_alloc(struct cxl_root_decoder *cxlrd, int i 
	 * region id allocations

	 */

	get_device(dev->parent);

	cxlr->cxlrd = cxlrd;

	cxlr->id = id;



	device_set_pm_not_required(dev);

	dev->bus = &cxl_bus_type;

	dev->type = &cxl_region_type;

	cxlr->id = id;

	cxl_region_set_lock(cxlr, &cxlrd->cxlsd.cxld);



	return cxlr;
@@ -3115,7 +3116,7 @@ EXPORT_SYMBOL_FOR_MODULES(cxl_calculate_hpa_offset, "cxl_translate"); 
u64 cxl_dpa_to_hpa(struct cxl_region *cxlr, const struct cxl_memdev *cxlmd,

		   u64 dpa)

{

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_region_params *p = &cxlr->params;

	struct cxl_endpoint_decoder *cxled = NULL;

	u64 dpa_offset, hpa_offset, hpa;
@@ -3168,7 +3169,7 @@ static int region_offset_to_dpa_result(struct cxl_region *cxlr, u64 offset, 
				       struct dpa_result *result)

{

	struct cxl_region_params *p = &cxlr->params;

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_endpoint_decoder *cxled;

	u64 hpa, hpa_offset, dpa_offset;

	u16 eig = 0;
@@ -3522,7 +3523,7 @@ static int match_region_by_range(struct device *dev, const void *data) 
static int cxl_extended_linear_cache_resize(struct cxl_region *cxlr,

					    struct resource *res)

{

	struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent);

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_region_params *p = &cxlr->params;

	resource_size_t size = resource_size(res);

	resource_size_t cache_size, start;
@@ -3558,9 +3559,9 @@ static int cxl_extended_linear_cache_resize(struct cxl_region *cxlr, 
}



static int __construct_region(struct cxl_region *cxlr,

			      struct cxl_root_decoder *cxlrd,

			      struct cxl_endpoint_decoder *cxled)

{

	struct cxl_root_decoder *cxlrd = cxlr->cxlrd;

	struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);

	struct range *hpa_range = &cxled->cxld.hpa_range;

	struct cxl_region_params *p;
@@ -3656,7 +3657,7 @@ static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd, 
		return cxlr;

	}



	rc = __construct_region(cxlr, cxlrd, cxled);

	rc = __construct_region(cxlr, cxled);

	if (rc) {

		devm_release_action(port->uport_dev, unregister_region, cxlr);

		return ERR_PTR(rc);

drivers/cxl/cxl.h

+2 −0
Original line number Diff line number Diff line
@@ -529,6 +529,7 @@ enum cxl_partition_mode { 
 * struct cxl_region - CXL region

 * @dev: This region's device

 * @id: This region's id. Id is globally unique across all regions

 * @cxlrd: Region's root decoder

 * @mode: Operational mode of the mapped capacity

 * @type: Endpoint decoder target type

 * @cxl_nvb: nvdimm bridge for coordinating @cxlr_pmem setup / shutdown
@@ -542,6 +543,7 @@ enum cxl_partition_mode { 
struct cxl_region {

	struct device dev;

	int id;

	struct cxl_root_decoder *cxlrd;

	enum cxl_partition_mode mode;

	enum cxl_decoder_type type;

	struct cxl_nvdimm_bridge *cxl_nvb;