5 files changed, 58 insertions, 6 deletions

diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
index 0df09bd79408..8567dd11eaac 100644
--- a/drivers/cxl/core/pci.c
+++ b/drivers/cxl/core/pci.c
@@ -525,7 +525,7 @@ static int cxl_cdat_get_length(struct device *dev,
 	__le32 response[2];
 	int rc;
 
-	rc = pci_doe(doe_mb, PCI_DVSEC_VENDOR_ID_CXL,
+	rc = pci_doe(doe_mb, PCI_VENDOR_ID_CXL,
 		     CXL_DOE_PROTOCOL_TABLE_ACCESS,
 		     &request, sizeof(request),
 		     &response, sizeof(response));
@@ -555,7 +555,7 @@ static int cxl_cdat_read_table(struct device *dev,
 		__le32 request = CDAT_DOE_REQ(entry_handle);
 		int rc;
 
-		rc = pci_doe(doe_mb, PCI_DVSEC_VENDOR_ID_CXL,
+		rc = pci_doe(doe_mb, PCI_VENDOR_ID_CXL,
 			     CXL_DOE_PROTOCOL_TABLE_ACCESS,
 			     &request, sizeof(request),
 			     rsp, sizeof(*rsp) + remaining);
@@ -640,7 +640,7 @@ void read_cdat_data(struct cxl_port *port)
 	if (!pdev)
 		return;
 
-	doe_mb = pci_find_doe_mailbox(pdev, PCI_DVSEC_VENDOR_ID_CXL,
+	doe_mb = pci_find_doe_mailbox(pdev, PCI_VENDOR_ID_CXL,
 				      CXL_DOE_PROTOCOL_TABLE_ACCESS);
 	if (!doe_mb) {
 		dev_dbg(dev, "No CDAT mailbox\n");
@@ -1045,3 +1045,32 @@ long cxl_pci_get_latency(struct pci_dev *pdev)
 
 	return cxl_flit_size(pdev) * MEGA / bw;
 }
+
+static int __cxl_endpoint_decoder_reset_detected(struct device *dev, void *data)
+{
+	struct cxl_port *port = data;
+	struct cxl_decoder *cxld;
+	struct cxl_hdm *cxlhdm;
+	void __iomem *hdm;
+	u32 ctrl;
+
+	if (!is_endpoint_decoder(dev))
+		return 0;
+
+	cxld = to_cxl_decoder(dev);
+	if ((cxld->flags & CXL_DECODER_F_ENABLE) == 0)
+		return 0;
+
+	cxlhdm = dev_get_drvdata(&port->dev);
+	hdm = cxlhdm->regs.hdm_decoder;
+	ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id));
+
+	return !FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl);
+}
+
+bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port)
+{
+	return device_for_each_child(&port->dev, port,
+				     __cxl_endpoint_decoder_reset_detected);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_endpoint_decoder_reset_detected, CXL);
diff --git a/drivers/cxl/core/regs.c b/drivers/cxl/core/regs.c
index 3c42f984eeaf..e1082e749c69 100644
--- a/drivers/cxl/core/regs.c
+++ b/drivers/cxl/core/regs.c
@@ -314,7 +314,7 @@ int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type,
 		.resource = CXL_RESOURCE_NONE,
 	};
 
-	regloc = pci_find_dvsec_capability(pdev, PCI_DVSEC_VENDOR_ID_CXL,
+	regloc = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL,
 					   CXL_DVSEC_REG_LOCATOR);
 	if (!regloc)
 		return -ENXIO;
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 80f58b96dc1c..603c0120cff8 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -898,6 +898,8 @@ void cxl_coordinates_combine(struct access_coordinate *out,
 			     struct access_coordinate *c1,
 			     struct access_coordinate *c2);
 
+bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
+
 /*
  * Unit test builds overrides this to __weak, find the 'strong' version
  * of these symbols in tools/testing/cxl/.
diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h
index 93992a1c8eec..4da07727ab9c 100644
--- a/drivers/cxl/cxlpci.h
+++ b/drivers/cxl/cxlpci.h
@@ -13,7 +13,6 @@
  * "DVSEC" redundancies removed. When obvious, abbreviations may be used.
  */
 #define PCI_DVSEC_HEADER1_LENGTH_MASK	GENMASK(31, 20)
-#define PCI_DVSEC_VENDOR_ID_CXL		0x1E98
 
 /* CXL 2.0 8.1.3: PCIe DVSEC for CXL Device */
 #define CXL_DVSEC_PCIE_DEVICE					0
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index 74876c9835e8..e53646e9f2fb 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -817,7 +817,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	cxlds->rcd = is_cxl_restricted(pdev);
 	cxlds->serial = pci_get_dsn(pdev);
 	cxlds->cxl_dvsec = pci_find_dvsec_capability(
-		pdev, PCI_DVSEC_VENDOR_ID_CXL, CXL_DVSEC_PCIE_DEVICE);
+		pdev, PCI_VENDOR_ID_CXL, CXL_DVSEC_PCIE_DEVICE);
 	if (!cxlds->cxl_dvsec)
 		dev_warn(&pdev->dev,
 			 "Device DVSEC not present, skip CXL.mem init\n");
@@ -957,11 +957,33 @@ static void cxl_error_resume(struct pci_dev *pdev)
 		 dev->driver ? "successful" : "failed");
 }
 
+static void cxl_reset_done(struct pci_dev *pdev)
+{
+	struct cxl_dev_state *cxlds = pci_get_drvdata(pdev);
+	struct cxl_memdev *cxlmd = cxlds->cxlmd;
+	struct device *dev = &pdev->dev;
+
+	/*
+	 * FLR does not expect to touch the HDM decoders and related
+	 * registers.  SBR, however, will wipe all device configurations.
+	 * Issue a warning if there was an active decoder before the reset
+	 * that no longer exists.
+	 */
+	guard(device)(&cxlmd->dev);
+	if (cxlmd->endpoint &&
+	    cxl_endpoint_decoder_reset_detected(cxlmd->endpoint)) {
+		dev_crit(dev, "SBR happened without memory regions removal.\n");
+		dev_crit(dev, "System may be unstable if regions hosted system memory.\n");
+		add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+	}
+}
+
 static const struct pci_error_handlers cxl_error_handlers = {
 	.error_detected	= cxl_error_detected,
 	.slot_reset	= cxl_slot_reset,
 	.resume		= cxl_error_resume,
 	.cor_error_detected	= cxl_cor_error_detected,
+	.reset_done	= cxl_reset_done,
 };
 
 static struct pci_driver cxl_pci_driver = {