Merge tag 'cxl-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull compute express link (cxl) updates from Dave Jiang:
 "Major changes address HDM decoder initialization from DVSEC ranges,
  refactoring the code related to cxl mailboxes to be independent of the
  memory devices, and adding support for shared upstream link
  access_coordinate calculation, as well as a change to remove locking
  from memory notifier callback.

  In addition, a number of misc cleanups and refactoring of the code are
  also included.

  Address HDM decoder initialization from DVSEC ranges:
   - Only register non-zero DVSEC ranges
   - Remove duplicate implementation of waiting for memory_info_valid
   - Simplify the checking of mem_enabled in  cxl_hdm_decode_init()

  Refactor the code related to cxl mailboxes to be independent of the memory devices:
   - Move cxl headers in include/linux/ to include/cxl
   - Move all mailbox related data to 'struct cxl_mailbox'
   - Refactor mailbox APIs with 'struct cxl_mailbox' as input instead of
     memory device state

  Add support for shared upstream link access_coordinate calculation for
  configurations that have multiple targets under a switch or a root
  port where the aggregated bandwidth can be greater than the upstream
  link of the switch/RP upstream link:
   - Preserve the CDAT access_coordinate from an endpoint
   - Add the support for shared upstream link access_coordinate calculation
   - Add documentation to explain how the calculations are done

  Remove locking from memory notifier callback.

  Misc cleanups:
   - Convert devm_cxl_add_root() to return using ERR_CAST()
   - cxl_test use dev_is_platform() instead of open coding
   - Remove duplicate include of header core.h in core/cdat.c
   - use scoped resource management to drop put_device() for cxl_port
   - Use scoped_guard to drop device_lock() for cxl_port
   - Refactor __devm_cxl_add_port() to drop gotos
   - Rename cxl_setup_parent_dport to cxl_dport_init_aer and
     cxl_dport_map_regs() to cxl_dport_map_ras()
   - Refactor cxl_dport_init_aer() to be more concise
   - Remove duplicate host_bridge->native_aer checking in
     cxl_dport_init_ras_reporting()
   - Fix comment for cxl_query_cmd()"

* tag 'cxl-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (21 commits)
  cxl: Add documentation to explain the shared link bandwidth calculation
  cxl: Calculate region bandwidth of targets with shared upstream link
  cxl: Preserve the CDAT access_coordinate for an endpoint
  cxl: Fix comment regarding cxl_query_cmd() return data
  cxl: Convert cxl_internal_send_cmd() to use 'struct cxl_mailbox' as input
  cxl: Move mailbox related bits to the same context
  cxl: move cxl headers to new include/cxl/ directory
  cxl/region: Remove lock from memory notifier callback
  cxl/pci: simplify the check of mem_enabled in cxl_hdm_decode_init()
  cxl/pci: Check Mem_info_valid bit for each applicable DVSEC
  cxl/pci: Remove duplicated implementation of waiting for memory_info_valid
  cxl/pci: Fix to record only non-zero ranges
  cxl/pci: Remove duplicate host_bridge->native_aer checking
  cxl/pci: cxl_dport_map_rch_aer() cleanup
  cxl/pci: Rename cxl_setup_parent_dport() and cxl_dport_map_regs()
  cxl/port: Refactor __devm_cxl_add_port() to drop goto pattern
  cxl/port: Use scoped_guard()/guard() to drop device_lock() for cxl_port
  cxl/port: Use __free() to drop put_device() for cxl_port
  cxl: Remove duplicate included header file core.h
  tools/testing/cxl: Use dev_is_platform()
  ...

1 files changed, 45 insertions, 36 deletions

diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 21ad5f242875..e701e4b04032 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -1983,6 +1983,7 @@ static int cxl_region_attach(struct cxl_region *cxlr,
 		 * then the region is already committed.
 		 */
 		p->state = CXL_CONFIG_COMMIT;
+		cxl_region_shared_upstream_bandwidth_update(cxlr);
 
 		return 0;
 	}
@@ -2004,6 +2005,7 @@ static int cxl_region_attach(struct cxl_region *cxlr,
 		if (rc)
 			return rc;
 		p->state = CXL_CONFIG_ACTIVE;
+		cxl_region_shared_upstream_bandwidth_update(cxlr);
 	}
 
 	cxled->cxld.interleave_ways = p->interleave_ways;
@@ -2313,8 +2315,6 @@ static void unregister_region(void *_cxlr)
 	struct cxl_region_params *p = &cxlr->params;
 	int i;
 
-	unregister_memory_notifier(&cxlr->memory_notifier);
-	unregister_mt_adistance_algorithm(&cxlr->adist_notifier);
 	device_del(&cxlr->dev);
 
 	/*
@@ -2391,18 +2391,6 @@ static bool cxl_region_update_coordinates(struct cxl_region *cxlr, int nid)
 	return true;
 }
 
-static int cxl_region_nid(struct cxl_region *cxlr)
-{
-	struct cxl_region_params *p = &cxlr->params;
-	struct resource *res;
-
-	guard(rwsem_read)(&cxl_region_rwsem);
-	res = p->res;
-	if (!res)
-		return NUMA_NO_NODE;
-	return phys_to_target_node(res->start);
-}
-
 static int cxl_region_perf_attrs_callback(struct notifier_block *nb,
 					  unsigned long action, void *arg)
 {
@@ -2415,7 +2403,11 @@ static int cxl_region_perf_attrs_callback(struct notifier_block *nb,
 	if (nid == NUMA_NO_NODE || action != MEM_ONLINE)
 		return NOTIFY_DONE;
 
-	region_nid = cxl_region_nid(cxlr);
+	/*
+	 * No need to hold cxl_region_rwsem; region parameters are stable
+	 * within the cxl_region driver.
+	 */
+	region_nid = phys_to_target_node(cxlr->params.res->start);
 	if (nid != region_nid)
 		return NOTIFY_DONE;
 
@@ -2434,7 +2426,11 @@ static int cxl_region_calculate_adistance(struct notifier_block *nb,
 	int *adist = data;
 	int region_nid;
 
-	region_nid = cxl_region_nid(cxlr);
+	/*
+	 * No need to hold cxl_region_rwsem; region parameters are stable
+	 * within the cxl_region driver.
+	 */
+	region_nid = phys_to_target_node(cxlr->params.res->start);
 	if (nid != region_nid)
 		return NOTIFY_OK;
 
@@ -2484,14 +2480,6 @@ static struct cxl_region *devm_cxl_add_region(struct cxl_root_decoder *cxlrd,
 	if (rc)
 		goto err;
 
-	cxlr->memory_notifier.notifier_call = cxl_region_perf_attrs_callback;
-	cxlr->memory_notifier.priority = CXL_CALLBACK_PRI;
-	register_memory_notifier(&cxlr->memory_notifier);
-
-	cxlr->adist_notifier.notifier_call = cxl_region_calculate_adistance;
-	cxlr->adist_notifier.priority = 100;
-	register_mt_adistance_algorithm(&cxlr->adist_notifier);
-
 	rc = devm_add_action_or_reset(port->uport_dev, unregister_region, cxlr);
 	if (rc)
 		return ERR_PTR(rc);
@@ -3094,11 +3082,11 @@ static void cxlr_release_nvdimm(void *_cxlr)
 	struct cxl_region *cxlr = _cxlr;
 	struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
 
-	device_lock(&cxl_nvb->dev);
-	if (cxlr->cxlr_pmem)
-		devm_release_action(&cxl_nvb->dev, cxlr_pmem_unregister,
-				    cxlr->cxlr_pmem);
-	device_unlock(&cxl_nvb->dev);
+	scoped_guard(device, &cxl_nvb->dev) {
+		if (cxlr->cxlr_pmem)
+			devm_release_action(&cxl_nvb->dev, cxlr_pmem_unregister,
+					    cxlr->cxlr_pmem);
+	}
 	cxlr->cxl_nvb = NULL;
 	put_device(&cxl_nvb->dev);
 }
@@ -3134,13 +3122,14 @@ static int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
 	dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent),
 		dev_name(dev));
 
-	device_lock(&cxl_nvb->dev);
-	if (cxl_nvb->dev.driver)
-		rc = devm_add_action_or_reset(&cxl_nvb->dev,
-					      cxlr_pmem_unregister, cxlr_pmem);
-	else
-		rc = -ENXIO;
-	device_unlock(&cxl_nvb->dev);
+	scoped_guard(device, &cxl_nvb->dev) {
+		if (cxl_nvb->dev.driver)
+			rc = devm_add_action_or_reset(&cxl_nvb->dev,
+						      cxlr_pmem_unregister,
+						      cxlr_pmem);
+		else
+			rc = -ENXIO;
+	}
 
 	if (rc)
 		goto err_bridge;
@@ -3386,6 +3375,14 @@ static int is_system_ram(struct resource *res, void *arg)
 	return 1;
 }
 
+static void shutdown_notifiers(void *_cxlr)
+{
+	struct cxl_region *cxlr = _cxlr;
+
+	unregister_memory_notifier(&cxlr->memory_notifier);
+	unregister_mt_adistance_algorithm(&cxlr->adist_notifier);
+}
+
 static int cxl_region_probe(struct device *dev)
 {
 	struct cxl_region *cxlr = to_cxl_region(dev);
@@ -3421,6 +3418,18 @@ out:
 	if (rc)
 		return rc;
 
+	cxlr->memory_notifier.notifier_call = cxl_region_perf_attrs_callback;
+	cxlr->memory_notifier.priority = CXL_CALLBACK_PRI;
+	register_memory_notifier(&cxlr->memory_notifier);
+
+	cxlr->adist_notifier.notifier_call = cxl_region_calculate_adistance;
+	cxlr->adist_notifier.priority = 100;
+	register_mt_adistance_algorithm(&cxlr->adist_notifier);
+
+	rc = devm_add_action_or_reset(&cxlr->dev, shutdown_notifiers, cxlr);
+	if (rc)
+		return rc;
+
 	switch (cxlr->mode) {
 	case CXL_DECODER_PMEM:
 		return devm_cxl_add_pmem_region(cxlr);