In 84ec985944ef3, devm_cxl_add_nvdimm() sequence was changed and called
before devm_cxl_add_endpoint(). It's because cxl pmem region auto-assembly
used to get called at last in cxl_endpoint_port_probe(), which requires
cxl_nvd presence.

For cxl region persistency, region creation happens during nvdimm_probe
which need the completion of endpoint probe.

In order to accommodate both cxl pmem region auto-assembly and cxl region
persistency, refactored following

1. Re-Sequence devm_cxl_add_nvdimm() after devm_cxl_add_endpoint(). This
   will be called only after successful completion of endpoint probe.

2. Moved cxl pmem region auto-assembly from cxl_endpoint_port_probe() to
   cxl_mem_probe() after devm_cxl_add_nvdimm(). It gurantees both the
   completion of endpoint probe and cxl_nvd presence before its call.

Signed-off-by: Neeraj Kumar <s.nee...@samsung.com>
---
 drivers/cxl/core/region.c | 33 +++++++++++++++++++++++++++++++++
 drivers/cxl/cxl.h         |  4 ++++
 drivers/cxl/mem.c         | 24 +++++++++++++++---------
 drivers/cxl/port.c        | 39 +--------------------------------------
 4 files changed, 53 insertions(+), 47 deletions(-)

diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 7a0cead24490..c325aa827992 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -3606,6 +3606,39 @@ int cxl_add_to_region(struct cxl_endpoint_decoder *cxled)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_add_to_region, "CXL");
 
+static int discover_region(struct device *dev, void *unused)
+{
+       struct cxl_endpoint_decoder *cxled;
+       int rc;
+
+       if (!is_endpoint_decoder(dev))
+               return 0;
+
+       cxled = to_cxl_endpoint_decoder(dev);
+       if ((cxled->cxld.flags & CXL_DECODER_F_ENABLE) == 0)
+               return 0;
+
+       if (cxled->state != CXL_DECODER_STATE_AUTO)
+               return 0;
+
+       /*
+        * Region enumeration is opportunistic, if this add-event fails,
+        * continue to the next endpoint decoder.
+        */
+       rc = cxl_add_to_region(cxled);
+       if (rc)
+               dev_dbg(dev, "failed to add to region: %#llx-%#llx\n",
+                       cxled->cxld.hpa_range.start, cxled->cxld.hpa_range.end);
+
+       return 0;
+}
+
+void cxl_region_discovery(struct cxl_port *port)
+{
+       device_for_each_child(&port->dev, NULL, discover_region);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_region_discovery, "CXL");
+
 u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint, u64 spa)
 {
        struct cxl_region_ref *iter;
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 4fe3df06f57a..b57597e55f7e 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -873,6 +873,7 @@ struct cxl_pmem_region *to_cxl_pmem_region(struct device 
*dev);
 int cxl_add_to_region(struct cxl_endpoint_decoder *cxled);
 struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
 u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint, u64 spa);
+void cxl_region_discovery(struct cxl_port *port);
 #else
 static inline bool is_cxl_pmem_region(struct device *dev)
 {
@@ -895,6 +896,9 @@ static inline u64 cxl_port_get_spa_cache_alias(struct 
cxl_port *endpoint,
 {
        return 0;
 }
+static inline void cxl_region_discovery(struct cxl_port *port)
+{
+}
 #endif
 
 void cxl_endpoint_parse_cdat(struct cxl_port *port);
diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 6e6777b7bafb..54501616ff09 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -152,15 +152,6 @@ static int cxl_mem_probe(struct device *dev)
                return -ENXIO;
        }
 
-       if (cxl_pmem_size(cxlds) && IS_ENABLED(CONFIG_CXL_PMEM)) {
-               rc = devm_cxl_add_nvdimm(parent_port, cxlmd);
-               if (rc) {
-                       if (rc == -ENODEV)
-                               dev_info(dev, "PMEM disabled by platform\n");
-                       return rc;
-               }
-       }
-
        if (dport->rch)
                endpoint_parent = parent_port->uport_dev;
        else
@@ -184,6 +175,21 @@ static int cxl_mem_probe(struct device *dev)
        if (rc)
                dev_dbg(dev, "CXL memdev EDAC registration failed rc=%d\n", rc);
 
+       if (cxl_pmem_size(cxlds) && IS_ENABLED(CONFIG_CXL_PMEM)) {
+               rc = devm_cxl_add_nvdimm(parent_port, cxlmd);
+               if (rc) {
+                       if (rc == -ENODEV)
+                               dev_info(dev, "PMEM disabled by platform\n");
+                       return rc;
+               }
+       }
+
+       /*
+        * Now that all endpoint decoders are successfully enumerated, try to
+        * assemble region autodiscovery from committed decoders.
+        */
+       cxl_region_discovery(cxlmd->endpoint);
+
        /*
         * The kernel may be operating out of CXL memory on this device,
         * there is no spec defined way to determine whether this device
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
index cf32dc50b7a6..07bb909b7d2e 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -30,33 +30,6 @@ static void schedule_detach(void *cxlmd)
        schedule_cxl_memdev_detach(cxlmd);
 }
 
-static int discover_region(struct device *dev, void *unused)
-{
-       struct cxl_endpoint_decoder *cxled;
-       int rc;
-
-       if (!is_endpoint_decoder(dev))
-               return 0;
-
-       cxled = to_cxl_endpoint_decoder(dev);
-       if ((cxled->cxld.flags & CXL_DECODER_F_ENABLE) == 0)
-               return 0;
-
-       if (cxled->state != CXL_DECODER_STATE_AUTO)
-               return 0;
-
-       /*
-        * Region enumeration is opportunistic, if this add-event fails,
-        * continue to the next endpoint decoder.
-        */
-       rc = cxl_add_to_region(cxled);
-       if (rc)
-               dev_dbg(dev, "failed to add to region: %#llx-%#llx\n",
-                       cxled->cxld.hpa_range.start, cxled->cxld.hpa_range.end);
-
-       return 0;
-}
-
 static int cxl_switch_port_probe(struct cxl_port *port)
 {
        struct cxl_hdm *cxlhdm;
@@ -121,17 +94,7 @@ static int cxl_endpoint_port_probe(struct cxl_port *port)
        if (rc)
                return rc;
 
-       rc = devm_cxl_enumerate_decoders(cxlhdm, &info);
-       if (rc)
-               return rc;
-
-       /*
-        * Now that all endpoint decoders are successfully enumerated, try to
-        * assemble regions from committed decoders
-        */
-       device_for_each_child(&port->dev, NULL, discover_region);
-
-       return 0;
+       return devm_cxl_enumerate_decoders(cxlhdm, &info);
 }
 
 static int cxl_port_probe(struct device *dev)
-- 
2.34.1


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