Merge tag 'cxl-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull CXL updates from Dave Jiang:
 "This includes the remaining patches to complete the basic support for
  CXL type2 (accelerators) drivers by the CXL core. A set of unit
  testing support to catch regressions for the CXL core type2 exported
  functions has also been added. The actual CXL type 2 driver support
  for the AMD Solarflare NIC driver has been picked up by net-dev.

  A set of preparatory patches has been picked up from the CXL port
  error handling series in order to reduce the number of patches in that
  series for review. The rest of that series is getting close to be
  merged but was not ready for the 7.3 merge window.

  There are also a number of misc patches and a large number of bug
  fixes against pre-existing issues flagged by sashiko reviews as
  contributors post new patches on the mailing list. We will continue to
  work through the sashiko raised issues as they show up."

* tag 'cxl-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (35 commits)
  cxl/Documentation: Spell out globbed sysfs attribute names
  cxl: Rename find_cxl_port() to find_cxl_port_by_dport()
  cxl: Tighten CPER kfifo registration API and symbol visibility
  acpi/apei/ghes: Use raw_spinlock_t for CXL CPER work locks
  cxl/ras: Fix cxl_rch_get_aer_severity() wrong severity register
  cxl/ras: Fix cxl_rch_get_aer_info() out-of-bounds AER register read
  cxl/test: Assign one mock memdev a full-width serial number
  cxl/core: Format the memdev serial number as unsigned in TP_printk
  cxl/pmem: Format the nvdimm serial number as unsigned decimal
  cxl: Use %pe to print error pointers
  cxl/region: Use __free(put_device) in find_pos_and_ways()
  cxl/region: Fix use-after-free in find_pos_and_ways() error path
  cxl: Deny Features commands on the RAW mailbox path
  cxl/features: Clamp Get Feature output size to the remaining buffer
  cxl/features: Reject Set Features output buffer smaller than the header
  cxl/features: Reject Get Feature count larger than the output buffer
  cxl/port: Restart port enumeration when a sibling adds the dport first
  cxl/features: Serialize multi-part Get/Set Feature transfers
  cxl/pci: Honor -EPROBE_DEFER from component register setup
  cxl/mbox: Break poison list loop on an empty payload
  ...

6 files changed, 692 insertions, 173 deletions

diff --git a/tools/testing/cxl/test/Kbuild b/tools/testing/cxl/test/Kbuild
index c168e3c998a7..9a24ddc28488 100644
--- a/tools/testing/cxl/test/Kbuild
+++ b/tools/testing/cxl/test/Kbuild
@@ -5,10 +5,12 @@ obj-m += cxl_test.o
 obj-m += cxl_mock.o
 obj-m += cxl_mock_mem.o
 obj-m += cxl_translate.o
+obj-m += cxl_mock_accel.o
 
 cxl_test-y := cxl.o
 cxl_test-y += hmem_test.o
 cxl_mock-y := mock.o
 cxl_mock_mem-y := mem.o
+cxl_mock_accel-y := accel.o
 
 KBUILD_CFLAGS := $(filter-out -Wmissing-prototypes -Wmissing-declarations, $(KBUILD_CFLAGS))
diff --git a/tools/testing/cxl/test/accel.c b/tools/testing/cxl/test/accel.c
new file mode 100644
index 000000000000..8e6f4687ca02
--- /dev/null
+++ b/tools/testing/cxl/test/accel.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright(c) 2026 Intel Corporation. All rights reserved.
+
+#include <linux/platform_device.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/sizes.h>
+#include <cxl/mailbox.h>
+#include <cxlmem.h>
+
+struct mock_cxl_accel {
+	struct cxl_dev_state cxlds;
+	struct cxl_memdev *cxlmd;
+};
+
+static int cxl_mock_accel_probe(struct platform_device *pdev)
+{
+	struct mock_cxl_accel *cxl_accel;
+	struct device *dev = &pdev->dev;
+	struct cxl_dev_state *cxlds;
+	struct cxl_memdev *cxlmd;
+	struct range mock_range;
+	int rc;
+
+	cxl_accel = devm_cxl_dev_state_create(&pdev->dev, CXL_DEVTYPE_DEVMEM,
+					      pdev->id + 1, 0,
+					      struct mock_cxl_accel, cxlds,
+					      false);
+	if (!cxl_accel)
+		return -ENOMEM;
+
+	cxlds = &cxl_accel->cxlds;
+	cxlds->media_ready = true;
+	rc = cxl_set_capacity(cxlds, SZ_512M);
+	if (rc)
+		return rc;
+
+	cxlmd = devm_cxl_probe_mem(cxlds, &mock_range);
+	if (IS_ERR(cxlmd))
+		return PTR_ERR(cxlmd);
+	cxl_accel->cxlmd = cxlmd;
+
+	dev_dbg(dev, "Probed mock accelerator with range %pra\n", &mock_range);
+
+	return 0;
+}
+
+static const struct platform_device_id cxl_mock_accel_ids[] = {
+	{ .name = "cxl_type2_accel" },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, cxl_mock_accel_ids);
+
+static struct platform_driver cxl_mock_accel_driver = {
+	.probe = cxl_mock_accel_probe,
+	.id_table = cxl_mock_accel_ids,
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
+};
+
+module_platform_driver(cxl_mock_accel_driver);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("cxl_test: accelerator device mock module");
+MODULE_IMPORT_NS("CXL");
diff --git a/tools/testing/cxl/test/cxl.c b/tools/testing/cxl/test/cxl.c
index ef92dd35e030..62bd92b3be45 100644
--- a/tools/testing/cxl/test/cxl.c
+++ b/tools/testing/cxl/test/cxl.c
@@ -17,6 +17,7 @@
 static int interleave_arithmetic;
 static bool extended_linear_cache;
 static bool fail_autoassemble;
+static bool type2_test;
 
 #define FAKE_QTG_ID	42
 
@@ -27,6 +28,7 @@ static bool fail_autoassemble;
 #define NR_CXL_SWITCH_PORTS 2
 #define NR_CXL_PORT_DECODERS 8
 #define NR_BRIDGES (NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST + NR_CXL_RCH)
+#define NR_CXL_TYPE2_ACCEL 1
 
 #define MOCK_AUTO_REGION_SIZE_DEFAULT SZ_512M
 static int mock_auto_region_size = MOCK_AUTO_REGION_SIZE_DEFAULT;
@@ -384,6 +386,19 @@ static struct {
 	},
 };
 
+static struct acpi_cedt_cfmws type2_cfmws0 = {
+	.header = {
+		.type = ACPI_CEDT_TYPE_CFMWS,
+		.length = sizeof(mock_cedt.cfmws0),
+	},
+	.interleave_ways = 0,
+	.granularity = 4,
+	.restrictions = ACPI_CEDT_CFMWS_RESTRICT_DEVMEM |
+			ACPI_CEDT_CFMWS_RESTRICT_VOLATILE,
+	.qtg_id = FAKE_QTG_ID,
+	.window_size = SZ_256M * 4,
+};
+
 struct acpi_cedt_cfmws *mock_cfmws[] = {
 	[0] = &mock_cedt.cfmws0.cfmws,
 	[1] = &mock_cedt.cfmws1.cfmws,
@@ -476,6 +491,11 @@ static void cfmws_elc_update(struct acpi_cedt_cfmws *window, int index)
 	window->window_size = mock_auto_region_size * 2;
 }
 
+static void update_type2_cfmws(void)
+{
+	memcpy(&mock_cedt.cfmws0.cfmws, &type2_cfmws0, sizeof(type2_cfmws0));
+}
+
 static int populate_cedt(void)
 {
 	struct cxl_mock_res *res;
@@ -497,11 +517,15 @@ static int populate_cedt(void)
 		chbs->length = size;
 	}
 
+	if (type2_test)
+		update_type2_cfmws();
+
 	for (i = cfmws_start; i <= cfmws_end; i++) {
 		struct acpi_cedt_cfmws *window = mock_cfmws[i];
 		int align = SZ_256M;
 
-		cfmws_elc_update(window, i);
+		if (i == 0 && !type2_test)
+			cfmws_elc_update(window, i);
 		if (window->restrictions & ACPI_CEDT_CFMWS_RESTRICT_VOLATILE)
 			align = max_t(int, SZ_256M, PMD_SIZE);
 		res = alloc_mock_res(window->window_size, align);
@@ -1060,74 +1084,26 @@ static int first_decoder(struct device *dev, const void *data)
 	return 0;
 }
 
-/*
- * Initialize a decoder during HDM enumeration.
- *
- * If a saved registry entry exists:
- *   - enabled decoders are restored from the saved programming
- *   - disabled decoders are initialized in a clean disabled state
- *
- * If no registry entry exists the decoder follows the normal mock
- * initialization path, including the special auto-region setup for
- * the first endpoints under host-bridge0.
- *
- * Returns true if decoder state was restored from the registry. In
- * that case the saved decode configuration (including target mapping)
- * has already been applied and the map_targets() is skipped.
- */
-static bool mock_init_hdm_decoder(struct cxl_decoder *cxld)
-{
-	struct acpi_cedt_cfmws *window = mock_cfmws[0];
-	struct platform_device *pdev = NULL;
-	struct cxl_endpoint_decoder *cxled;
-	struct cxl_switch_decoder *cxlsd;
-	struct cxl_port *port, *iter;
-	struct cxl_test_decoder *td;
-	struct cxl_memdev *cxlmd;
-	struct cxl_dport *dport;
-	struct device *dev;
-	bool hb0 = false;
-	u64 base;
-	int i;
+enum cxld_init_type {
+	MOCK_DECODER_INIT_DEFAULT,
+	MOCK_DECODER_INIT_SAVED,
+	MOCK_DECODER_INIT_TYPE3_AUTO,
+	MOCK_DECODER_INIT_TYPE2_AUTO,
+};
 
-	if (is_endpoint_decoder(&cxld->dev)) {
-		cxled = to_cxl_endpoint_decoder(&cxld->dev);
-		cxlmd = cxled_to_memdev(cxled);
-		WARN_ON(!dev_is_platform(cxlmd->dev.parent));
-		pdev = to_platform_device(cxlmd->dev.parent);
+static enum cxld_init_type get_decoder_init_type(struct cxl_decoder *cxld,
+						 struct platform_device *pdev,
+						 bool hb0,
+						 struct cxl_test_decoder **td)
+{
+	struct cxl_test_decoder *found_td = cxld_registry_find(cxld);
 
-		/* check is endpoint is attach to host-bridge0 */
-		port = cxled_to_port(cxled);
-		do {
-			if (port->uport_dev == &cxl_host_bridge[0]->dev) {
-				hb0 = true;
-				break;
-			}
-			if (is_cxl_port(port->dev.parent))
-				port = to_cxl_port(port->dev.parent);
-			else
-				port = NULL;
-		} while (port);
-		port = cxled_to_port(cxled);
-	} else {
-		port = to_cxl_port(cxld->dev.parent);
+	if (found_td) {
+		*td = found_td;
+		return MOCK_DECODER_INIT_SAVED;
 	}
 
-	td = cxld_registry_find(cxld);
-	if (td) {
-		bool enabled;
-
-		if (is_switch_decoder(&cxld->dev))
-			enabled = td->cxlsd.cxld.flags & CXL_DECODER_F_ENABLE;
-		else
-			enabled = td->cxled.cxld.flags & CXL_DECODER_F_ENABLE;
-
-		if (enabled)
-			return !cxld_registry_restore(cxld, td);
-
-		init_disabled_mock_decoder(cxld);
-		return false;
-	}
+	*td = NULL;
 
 	/*
 	 * The first decoder on the first 2 devices on the first switch
@@ -1138,15 +1114,119 @@ static bool mock_init_hdm_decoder(struct cxl_decoder *cxld)
 	 * See 'cxl list -BMPu -m cxl_mem.0,cxl_mem.4'
 	 */
 	if (!is_endpoint_decoder(&cxld->dev) || !hb0 || pdev->id % 4 ||
-	    pdev->id > 4 || cxld->id > 0) {
-		default_mock_decoder(cxld);
-		return false;
-	}
+	    pdev->id > 4 || cxld->id > 0)
+		return MOCK_DECODER_INIT_DEFAULT;
+
+	return type2_test ? MOCK_DECODER_INIT_TYPE2_AUTO :
+			    MOCK_DECODER_INIT_TYPE3_AUTO;
+}
+
+static bool mock_decoder_handle_saved(struct cxl_decoder *cxld, struct cxl_test_decoder *td)
+{
+	bool enabled;
+
+	if (is_switch_decoder(&cxld->dev))
+		enabled = td->cxlsd.cxld.flags & CXL_DECODER_F_ENABLE;
+	else
+		enabled = td->cxled.cxld.flags & CXL_DECODER_F_ENABLE;
+
+	if (enabled)
+		return !cxld_registry_restore(cxld, td);
+
+	init_disabled_mock_decoder(cxld);
+	return false;
+}
+
+static void mock_init_hdm_type2_cxled(struct cxl_endpoint_decoder *cxled,
+				      struct cxl_port *port)
+{
+	struct acpi_cedt_cfmws *window = mock_cfmws[0];
+	struct cxl_decoder *cxld = &cxled->cxld;
+	struct cxl_switch_decoder *cxlsd;
+	struct cxl_dport *dport;
+	struct cxl_port *root_port;
+	struct device *dev;
+	u64 base;
+
+	base = window->base_hpa;
+	cxld->hpa_range = (struct range) {
+		.start = base,
+		.end = base + mock_auto_region_size - 1,
+	};
+
+	cxld->interleave_ways = 1;
+	eig_to_granularity(window->granularity, &cxld->interleave_granularity);
+	cxld->target_type = CXL_DECODER_DEVMEM;
+	cxld->flags = CXL_DECODER_F_ENABLE;
+	cxled->state = CXL_DECODER_STATE_AUTO;
+	port->commit_end = cxld->id;
+	devm_cxl_dpa_reserve(cxled, 0,
+			     mock_auto_region_size / cxld->interleave_ways, 0);
+	cxld->commit = mock_decoder_commit;
+	cxld->reset = mock_decoder_reset;
+
+	WARN_ON_ONCE(!cxld_registry_new(cxld));
+	/*
+	 * Now that endpoint decoder is set up, walk up the hierarchy
+	 * and setup the root port decoder targeting @cxlmd.
+	 */
+	dport = port->parent_dport;
+	root_port = dport->port;
+	dev = device_find_child(&root_port->dev, NULL, first_decoder);
+	/*
+	 * Ancestor ports are guaranteed to be enumerated before
+	 * @port, and all ports have at least one decoder.
+	 */
+	if (WARN_ON(!dev))
+		return;
+
+	cxlsd = to_cxl_switch_decoder(dev);
+	cxld = &cxlsd->cxld;
+	cxld->target_type = CXL_DECODER_DEVMEM;
+	cxld->flags = CXL_DECODER_F_ENABLE;
+	root_port->commit_end = 0;
+	cxld->interleave_ways = 1;
+	cxld->interleave_granularity = 4096;
+	cxld->target_map[0] = dport->port_id;
+	cxld->hpa_range = (struct range) {
+		.start = base,
+		.end = base + mock_auto_region_size - 1,
+	};
+	cxld->commit = mock_decoder_commit;
+	cxld->reset = mock_decoder_reset;
+
+	/*
+	 * Only target_map[] is programmed above, mimicking
+	 * firmware. On real hardware target[] is populated as
+	 * dports enumerate, via update_decoder_targets(). The
+	 * mock's dports are already bound by now, so fire that
+	 * resolution explicitly here rather than stamping
+	 * target[] directly.
+	 */
+	cxl_port_update_decoder_targets(root_port, dport);
+
+	cxld_registry_update(cxld);
+	put_device(dev);
+}
+
+static void mock_init_hdm_type3_cxled(struct cxl_endpoint_decoder *cxled,
+				      struct cxl_port *port,
+				      struct platform_device *pdev,
+				      bool hb0)
+{
+	struct acpi_cedt_cfmws *window = mock_cfmws[0];
+	struct cxl_decoder *cxld = &cxled->cxld;
+	struct cxl_switch_decoder *cxlsd;
+	struct cxl_dport *dport;
+	struct cxl_port *iter;
+	struct device *dev;
+	u64 base;
+	int i;
 
 	/* Simulate missing cxl_mem.4 configuration */
 	if (hb0 && pdev->id == 4 && cxld->id == 0 && fail_autoassemble) {
 		default_mock_decoder(cxld);
-		return false;
+		return;
 	}
 
 	base = window->base_hpa;
@@ -1228,7 +1308,76 @@ static bool mock_init_hdm_decoder(struct cxl_decoder *cxld)
 		cxld_registry_update(cxld);
 		put_device(dev);
 	}
+}
 
+/*
+ * Initialize a decoder during HDM enumeration.
+ *
+ * If a saved registry entry exists:
+ *   - enabled decoders are restored from the saved programming
+ *   - disabled decoders are initialized in a clean disabled state
+ *
+ * If no registry entry exists the decoder follows the normal mock
+ * initialization path, including the special auto-region setup for
+ * the first endpoints under host-bridge0.
+ *
+ * Returns true if decoder state was restored from the registry. In
+ * that case the saved decode configuration (including target mapping)
+ * has already been applied and the map_targets() is skipped.
+ */
+static bool mock_init_hdm_decoder(struct cxl_decoder *cxld)
+{
+	struct cxl_endpoint_decoder *cxled = NULL;
+	struct platform_device *pdev = NULL;
+	struct cxl_test_decoder *td;
+	struct cxl_memdev *cxlmd;
+	struct cxl_port *port;
+	bool hb0 = false;
+
+	if (is_endpoint_decoder(&cxld->dev)) {
+		cxled = to_cxl_endpoint_decoder(&cxld->dev);
+		cxlmd = cxled_to_memdev(cxled);
+		WARN_ON(!dev_is_platform(cxlmd->dev.parent));
+		pdev = to_platform_device(cxlmd->dev.parent);
+
+		/* check is endpoint is attach to host-bridge0 */
+		port = cxled_to_port(cxled);
+		do {
+			if (port->uport_dev == &cxl_host_bridge[0]->dev) {
+				hb0 = true;
+				break;
+			}
+			if (is_cxl_port(port->dev.parent))
+				port = to_cxl_port(port->dev.parent);
+			else
+				port = NULL;
+		} while (port);
+		port = cxled_to_port(cxled);
+	} else {
+		port = to_cxl_port(cxld->dev.parent);
+	}
+
+	switch (get_decoder_init_type(cxld, pdev, hb0, &td)) {
+	case MOCK_DECODER_INIT_SAVED:
+		if (WARN_ON(!td))
+			return false;
+		return mock_decoder_handle_saved(cxld, td);
+	case MOCK_DECODER_INIT_DEFAULT:
+		/*
+		 * The default path picks up all the decoders that are not
+		 * endpoint.
+		 */
+		default_mock_decoder(cxld);
+		return false;
+	case MOCK_DECODER_INIT_TYPE3_AUTO:
+		mock_init_hdm_type3_cxled(cxled, port, pdev, hb0);
+		return false;
+	case MOCK_DECODER_INIT_TYPE2_AUTO:
+		mock_init_hdm_type2_cxled(cxled, port);
+		return false;
+	default:
+		return false;
+	}
 	return false;
 }
 
@@ -1563,8 +1712,10 @@ static __init int cxl_rch_topo_init(void)
 		struct platform_device *pdev;
 
 		pdev = platform_device_alloc("cxl_host_bridge", idx);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_bridge;
+		}
 
 		mock_companion(adev, &pdev->dev);
 		rc = cxl_mock_platform_device_add(pdev, &cxl_rch[i]);
@@ -1618,8 +1769,10 @@ static __init int cxl_single_topo_init(void)
 
 		pdev = platform_device_alloc("cxl_host_bridge",
 					     NR_CXL_HOST_BRIDGES + i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_bridge;
+		}
 
 		mock_companion(adev, &pdev->dev);
 		rc = cxl_mock_platform_device_add(pdev, &cxl_hb_single[i]);
@@ -1640,8 +1793,10 @@ static __init int cxl_single_topo_init(void)
 
 		pdev = platform_device_alloc("cxl_root_port",
 					     NR_MULTI_ROOT + i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_port;
+		}
 		pdev->dev.parent = &bridge->dev;
 
 		rc = cxl_mock_platform_device_add(pdev, &cxl_root_single[i]);
@@ -1655,8 +1810,10 @@ static __init int cxl_single_topo_init(void)
 
 		pdev = platform_device_alloc("cxl_switch_uport",
 					     NR_MULTI_ROOT + i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_uport;
+		}
 		pdev->dev.parent = &root_port->dev;
 
 		rc = cxl_mock_platform_device_add(pdev, &cxl_swu_single[i]);
@@ -1671,8 +1828,10 @@ static __init int cxl_single_topo_init(void)
 
 		pdev = platform_device_alloc("cxl_switch_dport",
 					     i + NR_MEM_MULTI);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_dport;
+		}
 		pdev->dev.parent = &uport->dev;
 
 		rc = cxl_mock_platform_device_add(pdev, &cxl_swd_single[i]);
@@ -1724,19 +1883,84 @@ static void cxl_single_topo_exit(void)
 	}
 }
 
-static void cxl_mem_exit(void)
+static void cxl_type3_mem_exit(void)
 {
+	struct platform_device *pdev;
 	int i;
 
-	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
+	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--) {
+		pdev = cxl_rcd[i];
+		if (!pdev)
+			continue;
 		platform_device_unregister(cxl_rcd[i]);
-	for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--)
+	}
+
+	for (i = ARRAY_SIZE(cxl_mem_single) - 1; i >= 0; i--) {
+		pdev = cxl_mem_single[i];
+		if (!pdev)
+			continue;
 		platform_device_unregister(cxl_mem_single[i]);
-	for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
+	}
+
+	for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--) {
+		pdev = cxl_mem[i];
+		if (!pdev)
+			continue;
+		platform_device_unregister(pdev);
+	}
+}
+
+static void cxl_type2_mem_exit(void)
+{
+	for (int i = NR_CXL_TYPE2_ACCEL - 1; i >= 0; i--) {
+		struct platform_device *pdev = cxl_mem[i];
+
+		if (!pdev)
+			continue;
+		platform_device_unregister(pdev);
+	}
+}
+
+static void cxl_mem_exit(void)
+{
+	if (type2_test) {
+		cxl_type2_mem_exit();
+		return;
+	}
+
+	cxl_type3_mem_exit();
+}
+
+static int cxl_type2_mem_init(void)
+{
+	int i, rc;
+
+	for (i = 0; i < NR_CXL_TYPE2_ACCEL; i++) {
+		struct platform_device *dport = cxl_root_port[i];
+		struct platform_device *pdev;
+
+		pdev = platform_device_alloc("cxl_type2_accel", i);
+		if (!pdev) {
+			rc = -ENOMEM;
+			goto err_mem;
+		}
+		pdev->dev.parent = &dport->dev;
+		set_dev_node(&pdev->dev, i % 2);
+
+		rc = cxl_mock_platform_device_add(pdev, &cxl_mem[i]);
+		if (rc)
+			goto err_mem;
+	}
+
+	return 0;
+
+err_mem:
+	for (i = NR_CXL_TYPE2_ACCEL - 1; i >= 0; i--)
 		platform_device_unregister(cxl_mem[i]);
+	return rc;
 }
 
-static int cxl_mem_init(void)
+static int cxl_type3_mem_init(void)
 {
 	int i, rc;
 
@@ -1745,8 +1969,10 @@ static int cxl_mem_init(void)
 		struct platform_device *pdev;
 
 		pdev = platform_device_alloc("cxl_mem", i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_mem;
+		}
 		pdev->dev.parent = &dport->dev;
 		set_dev_node(&pdev->dev, i % 2);
 
@@ -1760,8 +1986,10 @@ static int cxl_mem_init(void)
 		struct platform_device *pdev;
 
 		pdev = platform_device_alloc("cxl_mem", NR_MEM_MULTI + i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_single;
+		}
 		pdev->dev.parent = &dport->dev;
 		set_dev_node(&pdev->dev, i % 2);
 
@@ -1776,8 +2004,10 @@ static int cxl_mem_init(void)
 		struct platform_device *pdev;
 
 		pdev = platform_device_alloc("cxl_rcd", idx);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_rcd;
+		}
 		pdev->dev.parent = &rch->dev;
 		set_dev_node(&pdev->dev, i % 2);
 
@@ -1800,6 +2030,13 @@ err_mem:
 	return rc;
 }
 
+static int cxl_mem_init(void)
+{
+	if (type2_test)
+		return cxl_type2_mem_init();
+	return cxl_type3_mem_init();
+}
+
 static ssize_t
 decoder_reset_preserve_registry_show(struct device *dev,
 				     struct device_attribute *attr, char *buf)
@@ -1827,58 +2064,50 @@ static struct attribute *cxl_acpi_attrs[] = {
 };
 ATTRIBUTE_GROUPS(cxl_acpi);
 
-static __init int cxl_test_init(void)
+static bool __init have_multiple_modparms(void)
 {
-	int rc, i;
-	struct range mappable;
+	int count = 0;
 
-	if (!IS_ALIGNED(mock_auto_region_size, PMD_SIZE)) {
-		pr_err_once("mock_auto_region_size %d must be PMD-aligned\n",
-			    mock_auto_region_size);
-		return -EINVAL;
-	}
+	if (interleave_arithmetic)
+		count++;
+	if (extended_linear_cache)
+		count++;
+	if (hmem_test)
+		count++;
+	if (type2_test)
+		count++;
 
-	cxl_acpi_test();
-	cxl_core_test();
-	cxl_mem_test();
-	cxl_pmem_test();
-	cxl_port_test();
+	return count > 1;
+}
 
-	register_cxl_mock_ops(&cxl_mock_ops);
+static void host_bridges_remove(void)
+{
+	int i;
 
-	cxl_mock_pool = gen_pool_create(ilog2(SZ_2M), NUMA_NO_NODE);
-	if (!cxl_mock_pool) {
-		rc = -ENOMEM;
-		goto err_gen_pool_create;
-	}
-	mappable = mhp_get_pluggable_range(true);
+	for (i = ARRAY_SIZE(cxl_host_bridge) - 1; i >= 0; i--) {
+		struct platform_device *pdev = cxl_host_bridge[i];
 
-	rc = gen_pool_add(cxl_mock_pool,
-			  min(iomem_resource.end + 1 - SZ_64G,
-			      mappable.end + 1 - SZ_64G),
-			  SZ_64G, NUMA_NO_NODE);
-	if (rc)
-		goto err_gen_pool_add;
+		if (!pdev)
+			continue;
 
-	if (interleave_arithmetic == 1) {
-		cfmws_start = CFMWS_XOR_ARRAY_START;
-		cfmws_end = CFMWS_XOR_ARRAY_END;
-	} else {
-		cfmws_start = CFMWS_MOD_ARRAY_START;
-		cfmws_end = CFMWS_MOD_ARRAY_END;
+		sysfs_remove_link(&pdev->dev.kobj, "physical_node");
+		platform_device_unregister(cxl_host_bridge[i]);
 	}
+}
 
-	rc = populate_cedt();
-	if (rc)
-		goto err_populate;
+static int host_bridges_populate(void)
+{
+	int rc = 0;
 
-	for (i = 0; i < ARRAY_SIZE(cxl_host_bridge); i++) {
+	for (int i = 0; i < ARRAY_SIZE(cxl_host_bridge); i++) {
 		struct acpi_device *adev = &host_bridge[i];
 		struct platform_device *pdev;
 
 		pdev = platform_device_alloc("cxl_host_bridge", i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_bridge;
+		}
 
 		mock_companion(adev, &pdev->dev);
 		rc = cxl_mock_platform_device_add(pdev, &cxl_host_bridge[i]);
@@ -1892,14 +2121,40 @@ static __init int cxl_test_init(void)
 			goto err_bridge;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(cxl_root_port); i++) {
+	return 0;
+
+err_bridge:
+	host_bridges_remove();
+	return rc;
+}
+
+static void cxl_rootports_remove(void)
+{
+	for (int i = ARRAY_SIZE(cxl_root_port) - 1; i >= 0; i--) {
+		struct platform_device *pdev = cxl_root_port[i];
+
+		if (!pdev)
+			continue;
+
+		platform_device_unregister(pdev);
+	}
+}
+
+static int cxl_rootports_populate(void)
+{
+	int rc = 0;
+
+	for (int i = 0; i < ARRAY_SIZE(cxl_root_port); i++) {
 		struct platform_device *bridge =
 			cxl_host_bridge[i % ARRAY_SIZE(cxl_host_bridge)];
 		struct platform_device *pdev;
 
 		pdev = platform_device_alloc("cxl_root_port", i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_port;
+		}
+
 		pdev->dev.parent = &bridge->dev;
 
 		rc = cxl_mock_platform_device_add(pdev, &cxl_root_port[i]);
@@ -1907,14 +2162,39 @@ static __init int cxl_test_init(void)
 			goto err_port;
 	}
 
-	BUILD_BUG_ON(ARRAY_SIZE(cxl_switch_uport) != ARRAY_SIZE(cxl_root_port));
-	for (i = 0; i < ARRAY_SIZE(cxl_switch_uport); i++) {
+	return 0;
+
+err_port:
+	cxl_rootports_remove();
+	return rc;
+}
+
+static void cxl_usps_remove(void)
+{
+	for (int i = ARRAY_SIZE(cxl_switch_uport) - 1; i >= 0; i--) {
+		struct platform_device *pdev = cxl_switch_uport[i];
+
+		if (!pdev)
+			continue;
+
+		platform_device_unregister(cxl_switch_uport[i]);
+	}
+}
+
+static int cxl_usps_populate(void)
+{
+	int rc = 0;
+
+	for (int i = 0; i < ARRAY_SIZE(cxl_switch_uport); i++) {
 		struct platform_device *root_port = cxl_root_port[i];
 		struct platform_device *pdev;
 
 		pdev = platform_device_alloc("cxl_switch_uport", i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_uport;
+		}
+
 		pdev->dev.parent = &root_port->dev;
 
 		rc = cxl_mock_platform_device_add(pdev, &cxl_switch_uport[i]);
@@ -1922,14 +2202,40 @@ static __init int cxl_test_init(void)
 			goto err_uport;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(cxl_switch_dport); i++) {
+	return 0;
+
+err_uport:
+	cxl_usps_remove();
+	return rc;
+}
+
+static void cxl_dsps_remove(void)
+{
+	for (int i = ARRAY_SIZE(cxl_switch_dport) - 1; i >= 0; i--) {
+		struct platform_device *pdev = cxl_switch_dport[i];
+
+		if (!pdev)
+			continue;
+
+		platform_device_unregister(cxl_switch_dport[i]);
+	}
+}
+
+
+static int cxl_dsps_populate(void)
+{
+	int rc = 0;
+
+	for (int i = 0; i < ARRAY_SIZE(cxl_switch_dport); i++) {
 		struct platform_device *uport =
 			cxl_switch_uport[i % ARRAY_SIZE(cxl_switch_uport)];
 		struct platform_device *pdev;
 
 		pdev = platform_device_alloc("cxl_switch_dport", i);
-		if (!pdev)
+		if (!pdev) {
+			rc = -ENOMEM;
 			goto err_dport;
+		}
 		pdev->dev.parent = &uport->dev;
 
 		rc = cxl_mock_platform_device_add(pdev, &cxl_switch_dport[i]);
@@ -1937,17 +2243,181 @@ static __init int cxl_test_init(void)
 			goto err_dport;
 	}
 
+	return 0;
+
+err_dport:
+	cxl_dsps_remove();
+	return rc;
+}
+
+static void cxl_switches_remove(void)
+{
+	cxl_dsps_remove();
+	cxl_usps_remove();
+}
+
+static int cxl_switches_populate(void)
+{
+	int rc;
+
+	BUILD_BUG_ON(ARRAY_SIZE(cxl_switch_uport) != ARRAY_SIZE(cxl_root_port));
+	rc = cxl_usps_populate();
+	if (rc)
+		return rc;
+
+	rc = cxl_dsps_populate();
+	if (rc) {
+		cxl_usps_remove();
+		return rc;
+	}
+
+	return 0;
+}
+
+static void cxl_type2_topo_exit(void)
+{
+	cxl_rootports_remove();
+	host_bridges_remove();
+}
+
+static int cxl_type2_topo_init(void)
+{
+	int rc;
+
+	rc = host_bridges_populate();
+	if (rc)
+		return rc;
+
+	rc = cxl_rootports_populate();
+	if (rc) {
+		host_bridges_remove();
+		return rc;
+	}
+
+	return 0;
+}
+
+static void cxl_type3_topo_exit(void)
+{
+	cxl_rch_topo_exit();
+	cxl_single_topo_exit();
+	cxl_switches_remove();
+	cxl_rootports_remove();
+	host_bridges_remove();
+}
+
+static int cxl_type3_topo_init(void)
+{
+	int rc;
+
+	rc = host_bridges_populate();
+	if (rc)
+		return rc;
+
+	rc = cxl_rootports_populate();
+	if (rc)
+		goto err_host_bridges;
+
+	rc = cxl_switches_populate();
+	if (rc)
+		goto err_root_ports;
+
 	rc = cxl_single_topo_init();
 	if (rc)
-		goto err_dport;
+		goto err_switches;
 
 	rc = cxl_rch_topo_init();
 	if (rc)
 		goto err_single;
 
+	return 0;
+
+err_single:
+	cxl_single_topo_exit();
+err_switches:
+	cxl_switches_remove();
+err_root_ports:
+	cxl_rootports_remove();
+err_host_bridges:
+	host_bridges_remove();
+	return rc;
+}
+
+static void cxl_topo_exit(void)
+{
+	if (type2_test) {
+		cxl_type2_topo_exit();
+		return;
+	}
+
+	cxl_type3_topo_exit();
+}
+
+static int cxl_topo_init(void)
+{
+	if (type2_test)
+		return cxl_type2_topo_init();
+	return cxl_type3_topo_init();
+}
+
+static __init int cxl_test_init(void)
+{
+	struct range mappable;
+	int rc;
+
+	/* Enforce a single module param active at a time */
+	if (have_multiple_modparms())
+		return -EINVAL;
+
+	if (!IS_ALIGNED(mock_auto_region_size, PMD_SIZE)) {
+		pr_err_once("mock_auto_region_size %d must be PMD-aligned\n",
+			    mock_auto_region_size);
+		return -EINVAL;
+	}
+
+	cxl_acpi_test();
+	cxl_core_test();
+	cxl_mem_test();
+	cxl_pmem_test();
+	cxl_port_test();
+
+	register_cxl_mock_ops(&cxl_mock_ops);
+
+	cxl_mock_pool = gen_pool_create(ilog2(SZ_2M), NUMA_NO_NODE);
+	if (!cxl_mock_pool) {
+		rc = -ENOMEM;
+		goto err_gen_pool_create;
+	}
+	mappable = mhp_get_pluggable_range(true);
+
+	rc = gen_pool_add(cxl_mock_pool,
+			  min(iomem_resource.end + 1 - SZ_64G,
+			      mappable.end + 1 - SZ_64G),
+			  SZ_64G, NUMA_NO_NODE);
+	if (rc)
+		goto err_gen_pool_add;
+
+	if (interleave_arithmetic == 1) {
+		cfmws_start = CFMWS_XOR_ARRAY_START;
+		cfmws_end = CFMWS_XOR_ARRAY_END;
+	} else {
+		cfmws_start = CFMWS_MOD_ARRAY_START;
+		cfmws_end = CFMWS_MOD_ARRAY_END;
+	}
+
+	rc = populate_cedt();
+	if (rc)
+		goto err_populate;
+
+	rc = cxl_topo_init();
+	if (rc)
+		goto err_populate;
+
 	cxl_acpi = platform_device_alloc("cxl_acpi", 0);
-	if (!cxl_acpi)
-		goto err_rch;
+	if (!cxl_acpi) {
+		rc = -ENOMEM;
+		goto err_topo;
+	}
 
 	mock_companion(&acpi0017_mock, &cxl_acpi->dev);
 	acpi0017_mock.dev.bus = &platform_bus_type;
@@ -1955,7 +2425,7 @@ static __init int cxl_test_init(void)
 
 	rc = cxl_mock_platform_device_add(cxl_acpi, NULL);
 	if (rc)
-		goto err_rch;
+		goto err_topo;
 
 	rc = cxl_mem_init();
 	if (rc)
@@ -1971,28 +2441,8 @@ err_mem:
 	cxl_mem_exit();
 err_root:
 	platform_device_unregister(cxl_acpi);
-err_rch:
-	cxl_rch_topo_exit();
-err_single:
-	cxl_single_topo_exit();
-err_dport:
-	for (i = ARRAY_SIZE(cxl_switch_dport) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_switch_dport[i]);
-err_uport:
-	for (i = ARRAY_SIZE(cxl_switch_uport) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_switch_uport[i]);
-err_port:
-	for (i = ARRAY_SIZE(cxl_root_port) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_root_port[i]);
-err_bridge:
-	for (i = ARRAY_SIZE(cxl_host_bridge) - 1; i >= 0; i--) {
-		struct platform_device *pdev = cxl_host_bridge[i];
-
-		if (!pdev)
-			continue;
-		sysfs_remove_link(&pdev->dev.kobj, "physical_node");
-		platform_device_unregister(cxl_host_bridge[i]);
-	}
+err_topo:
+	cxl_topo_exit();
 err_populate:
 	depopulate_all_mock_resources();
 err_gen_pool_add:
@@ -2015,27 +2465,10 @@ static void free_decoder_registry(void)
 
 static __exit void cxl_test_exit(void)
 {
-	int i;
-
 	hmem_test_exit();
 	cxl_mem_exit();
 	platform_device_unregister(cxl_acpi);
-	cxl_rch_topo_exit();
-	cxl_single_topo_exit();
-	for (i = ARRAY_SIZE(cxl_switch_dport) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_switch_dport[i]);
-	for (i = ARRAY_SIZE(cxl_switch_uport) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_switch_uport[i]);
-	for (i = ARRAY_SIZE(cxl_root_port) - 1; i >= 0; i--)
-		platform_device_unregister(cxl_root_port[i]);
-	for (i = ARRAY_SIZE(cxl_host_bridge) - 1; i >= 0; i--) {
-		struct platform_device *pdev = cxl_host_bridge[i];
-
-		if (!pdev)
-			continue;
-		sysfs_remove_link(&pdev->dev.kobj, "physical_node");
-		platform_device_unregister(cxl_host_bridge[i]);
-	}
+	cxl_topo_exit();
 	depopulate_all_mock_resources();
 	gen_pool_destroy(cxl_mock_pool);
 	unregister_cxl_mock_ops(&cxl_mock_ops);
@@ -2049,6 +2482,8 @@ module_param(extended_linear_cache, bool, 0444);
 MODULE_PARM_DESC(extended_linear_cache, "Enable extended linear cache support");
 module_param(fail_autoassemble, bool, 0444);
 MODULE_PARM_DESC(fail_autoassemble, "Simulate missing member of an auto-region");
+module_param(type2_test, bool, 0444);
+MODULE_PARM_DESC(type2_test, "Enable type 2 support testing");
 module_init(cxl_test_init);
 module_exit(cxl_test_exit);
 MODULE_LICENSE("GPL v2");
diff --git a/tools/testing/cxl/test/hmem_test.c b/tools/testing/cxl/test/hmem_test.c
index 3a1a089e1721..0fa00f7e16db 100644
--- a/tools/testing/cxl/test/hmem_test.c
+++ b/tools/testing/cxl/test/hmem_test.c
@@ -3,8 +3,9 @@
 #include <linux/moduleparam.h>
 #include <linux/workqueue.h>
 #include "../../../drivers/dax/bus.h"
+#include "mock.h"
 
-static bool hmem_test;
+bool hmem_test;
 
 static void hmem_test_work(struct work_struct *work)
 {
diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
index a7da279aa3ef..7b756000a1a6 100644
--- a/tools/testing/cxl/test/mem.c
+++ b/tools/testing/cxl/test/mem.c
@@ -1713,6 +1713,7 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
 	struct cxl_mockmem_data *mdata;
 	struct cxl_mailbox *cxl_mbox;
 	struct cxl_dpa_info range_info = { 0 };
+	u64 serial;
 	int rc;
 
 	/* Increase async probe race window */
@@ -1739,7 +1740,19 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
 	if (rc)
 		return rc;
 
-	mds = cxl_memdev_state_create(dev, pdev->id + 1, 0);
+	/*
+	 * Mock serials have historically been derived from pdev->id and stayed
+	 * single-digit, so they never exercised either decimal-vs-hex key
+	 * lookup or unsigned formatting. Give one mock device a full-width
+	 * serial with bit 63 set, matching real hardware such as Montage CXL
+	 * devices. pdev->id 7 is unused by the auto-region topology.
+	 */
+	if (pdev->id == 7)
+		serial = 0x8a34567890abcdef;
+	else
+		serial = pdev->id + 1;
+
+	mds = cxl_memdev_state_create(dev, serial, 0);
 	if (IS_ERR(mds))
 		return PTR_ERR(mds);
 
diff --git a/tools/testing/cxl/test/mock.h b/tools/testing/cxl/test/mock.h
index 4f57dc80ae7d..846d7c5d6eaa 100644
--- a/tools/testing/cxl/test/mock.h
+++ b/tools/testing/cxl/test/mock.h
@@ -5,6 +5,8 @@
 #include <linux/dax.h>
 #include <cxl.h>
 
+extern bool hmem_test;
+
 struct cxl_mock_ops {
 	struct list_head list;
 	bool (*is_mock_adev)(struct acpi_device *dev);