1 files changed, 24 insertions, 124 deletions

diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 49a4b1c47299..c310f1fd3db0 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -24,27 +24,6 @@
  * in higher level operations.
  */
 
-static int wait_for_media(struct cxl_memdev *cxlmd)
-{
-	struct cxl_dev_state *cxlds = cxlmd->cxlds;
-	struct cxl_endpoint_dvsec_info *info = &cxlds->info;
-	int rc;
-
-	if (!info->mem_enabled)
-		return -EBUSY;
-
-	rc = cxlds->wait_media_ready(cxlds);
-	if (rc)
-		return rc;
-
-	/*
-	 * We know the device is active, and enabled, if any ranges are non-zero
-	 * we'll need to check later before adding the port since that owns the
-	 * HDM decoder registers.
-	 */
-	return 0;
-}
-
 static int create_endpoint(struct cxl_memdev *cxlmd,
 			   struct cxl_port *parent_port)
 {
@@ -67,72 +46,14 @@ static int create_endpoint(struct cxl_memdev *cxlmd,
 	return cxl_endpoint_autoremove(cxlmd, endpoint);
 }
 
-/**
- * cxl_dvsec_decode_init() - Setup HDM decoding for the endpoint
- * @cxlds: Device state
- *
- * Additionally, enables global HDM decoding. Warning: don't call this outside
- * of probe. Once probe is complete, the port driver owns all access to the HDM
- * decoder registers.
- *
- * Returns: false if DVSEC Ranges are being used instead of HDM
- * decoders, or if it can not be determined if DVSEC Ranges are in use.
- * Otherwise, returns true.
- */
-__mock bool cxl_dvsec_decode_init(struct cxl_dev_state *cxlds)
+static void enable_suspend(void *data)
 {
-	struct cxl_endpoint_dvsec_info *info = &cxlds->info;
-	struct cxl_register_map map;
-	struct cxl_component_reg_map *cmap = &map.component_map;
-	bool global_enable, do_hdm_init = false;
-	void __iomem *crb;
-	u32 global_ctrl;
-
-	/* map hdm decoder */
-	crb = ioremap(cxlds->component_reg_phys, CXL_COMPONENT_REG_BLOCK_SIZE);
-	if (!crb) {
-		dev_dbg(cxlds->dev, "Failed to map component registers\n");
-		return false;
-	}
-
-	cxl_probe_component_regs(cxlds->dev, crb, cmap);
-	if (!cmap->hdm_decoder.valid) {
-		dev_dbg(cxlds->dev, "Invalid HDM decoder registers\n");
-		goto out;
-	}
-
-	global_ctrl = readl(crb + cmap->hdm_decoder.offset +
-			    CXL_HDM_DECODER_CTRL_OFFSET);
-	global_enable = global_ctrl & CXL_HDM_DECODER_ENABLE;
-	if (!global_enable && info->ranges) {
-		dev_dbg(cxlds->dev,
-			"DVSEC ranges already programmed and HDM decoders not enabled.\n");
-		goto out;
-	}
-
-	do_hdm_init = true;
-
-	/*
-	 * Permanently (for this boot at least) opt the device into HDM
-	 * operation. Individual HDM decoders still need to be enabled after
-	 * this point.
-	 */
-	if (!global_enable) {
-		dev_dbg(cxlds->dev, "Enabling HDM decode\n");
-		writel(global_ctrl | CXL_HDM_DECODER_ENABLE,
-		       crb + cmap->hdm_decoder.offset +
-			       CXL_HDM_DECODER_CTRL_OFFSET);
-	}
-
-out:
-	iounmap(crb);
-	return do_hdm_init;
+	cxl_mem_active_dec();
 }
 
 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;
 	int rc;
 
@@ -147,44 +68,6 @@ static int cxl_mem_probe(struct device *dev)
 	if (work_pending(&cxlmd->detach_work))
 		return -EBUSY;
 
-	rc = wait_for_media(cxlmd);
-	if (rc) {
-		dev_err(dev, "Media not active (%d)\n", rc);
-		return rc;
-	}
-
-	/*
-	 * If DVSEC ranges are being used instead of HDM decoder registers there
-	 * is no use in trying to manage those.
-	 */
-	if (!cxl_dvsec_decode_init(cxlds)) {
-		struct cxl_endpoint_dvsec_info *info = &cxlds->info;
-		int i;
-
-		/* */
-		for (i = 0; i < 2; i++) {
-			u64 base, size;
-
-			/*
-			 * Give a nice warning to the user that BIOS has really
-			 * botched things for them if it didn't place DVSEC
-			 * ranges in the memory map.
-			 */
-			base = info->dvsec_range[i].start;
-			size = range_len(&info->dvsec_range[i]);
-			if (size && !region_intersects(base, size,
-						       IORESOURCE_SYSTEM_RAM,
-						       IORES_DESC_NONE)) {
-				dev_err(dev,
-					"DVSEC range %#llx-%#llx must be reserved by BIOS, but isn't\n",
-					base, base + size - 1);
-			}
-		}
-		dev_err(dev,
-			"Active DVSEC range registers in use. Will not bind.\n");
-		return -EBUSY;
-	}
-
 	rc = devm_cxl_enumerate_ports(cxlmd);
 	if (rc)
 		return rc;
@@ -195,19 +78,36 @@ static int cxl_mem_probe(struct device *dev)
 		return -ENXIO;
 	}
 
-	cxl_device_lock(&parent_port->dev);
+	device_lock(&parent_port->dev);
 	if (!parent_port->dev.driver) {
 		dev_err(dev, "CXL port topology %s not enabled\n",
 			dev_name(&parent_port->dev));
 		rc = -ENXIO;
-		goto out;
+		goto unlock;
 	}
 
 	rc = create_endpoint(cxlmd, parent_port);
-out:
-	cxl_device_unlock(&parent_port->dev);
+unlock:
+	device_unlock(&parent_port->dev);
 	put_device(&parent_port->dev);
-	return rc;
+	if (rc)
+		return rc;
+
+	/*
+	 * The kernel may be operating out of CXL memory on this device,
+	 * there is no spec defined way to determine whether this device
+	 * preserves contents over suspend, and there is no simple way
+	 * to arrange for the suspend image to avoid CXL memory which
+	 * would setup a circular dependency between PCI resume and save
+	 * state restoration.
+	 *
+	 * TODO: support suspend when all the regions this device is
+	 * hosting are locked and covered by the system address map,
+	 * i.e. platform firmware owns restoring the HDM configuration
+	 * that it locked.
+	 */
+	cxl_mem_active_inc();
+	return devm_add_action_or_reset(dev, enable_suspend, NULL);
 }
 
 static struct cxl_driver cxl_mem_driver = {