[PATCH 05/13] cxl/mem: Cache port created by the mem dev

From: Ben Widawsky <ben.widawsky@intel.com>
To: linux-cxl@vger.kernel.org, linux-nvdimm@lists.01.org,
	linux-pci@vger.kernel.org
Cc: patches@lists.linux.dev, Bjorn Helgaas <helgaas@kernel.org>,
	Ben Widawsky <ben.widawsky@intel.com>,
	Alison Schofield <alison.schofield@intel.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Ira Weiny <ira.weiny@intel.com>,
	Jonathan Cameron <Jonathan.Cameron@Huawei.com>,
	Vishal Verma <vishal.l.verma@intel.com>
Subject: [PATCH 05/13] cxl/mem: Cache port created by the mem dev
Date: Thu,  6 Jan 2022 16:37:48 -0800	[thread overview]
Message-ID: <20220107003756.806582-6-ben.widawsky@intel.com> (raw)
In-Reply-To: <20220107003756.806582-1-ben.widawsky@intel.com>

Since region programming sees all components in the topology as a port,
it's required that endpoints are treated equally. The easiest way to go
from endpoint to port is to simply cache it at creation time.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
---
 drivers/cxl/cxlmem.h |  2 ++
 drivers/cxl/mem.c    | 16 ++++++++++------
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 4ea0686e5f84..38d6129499c8 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -36,12 +36,14 @@
  * @cxlds: The device state backing this device
  * @id: id number of this memdev instance.
  * @component_reg_phys: register base of component registers
+ * @port: The port created by this device
  */
 struct cxl_memdev {
 	struct device dev;
 	struct cdev cdev;
 	struct cxl_dev_state *cxlds;
 	int id;
+	struct cxl_port *port;
 };
 
 static inline struct cxl_memdev *to_cxl_memdev(struct device *dev)
diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 9e6e98e5ea06..2ed7554155d2 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -45,8 +45,8 @@ static int wait_for_media(struct cxl_memdev *cxlmd)
 	return 0;
 }
 
-static int create_endpoint(struct cxl_memdev *cxlmd,
-			   struct cxl_port *parent_port)
+static struct cxl_port *create_endpoint(struct cxl_memdev *cxlmd,
+					struct cxl_port *parent_port)
 {
 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
 	struct cxl_port *endpoint;
@@ -54,10 +54,10 @@ static int create_endpoint(struct cxl_memdev *cxlmd,
 	endpoint = devm_cxl_add_port(&parent_port->dev, &cxlmd->dev,
 				     cxlds->component_reg_phys, parent_port);
 	if (IS_ERR(endpoint))
-		return PTR_ERR(endpoint);
+		return endpoint;
 
 	dev_dbg(&cxlmd->dev, "add: %s\n", dev_name(&endpoint->dev));
-	return 0;
+	return endpoint;
 }
 
 /**
@@ -123,7 +123,7 @@ static int cxl_mem_probe(struct device *dev)
 {
 	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
-	struct cxl_port *parent_port;
+	struct cxl_port *parent_port, *ep_port;
 	int rc;
 
 	rc = wait_for_media(cxlmd);
@@ -182,7 +182,11 @@ static int cxl_mem_probe(struct device *dev)
 		goto out;
 	}
 
-	rc = create_endpoint(cxlmd, parent_port);
+	ep_port = create_endpoint(cxlmd, parent_port);
+	if (IS_ERR(ep_port))
+		rc = PTR_ERR(ep_port);
+	else
+		cxlmd->port = ep_port;
 out:
 	device_unlock(&parent_port->dev);
 	put_device(&parent_port->dev);
-- 
2.34.1

