From: Ben Widawsky <ben.widawsky@xxxxxxxxx>
The PCIe device DVSEC, defined in the CXL 2.0 spec, 8.1.3 is required to
be implemented by CXL 2.0 endpoint devices. In preparation for consuming
this information in a new cxl_mem driver, retrieve the CXL DVSEC
position and warn about the implications of not finding it. Allow for
mailbox operation even if the CXL DVSEC is missing.
Signed-off-by: Ben Widawsky <ben.widawsky@xxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
Changes since v3:
- Move the s/device_dvsec/cxl_dvsec/ rename one patch sooner (Jonathan)
- Warn, don't fail, when CXL DVSEC not found
drivers/cxl/cxlmem.h | 2 ++
drivers/cxl/pci.c | 6 ++++++
2 files changed, 8 insertions(+)
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 90d67fff5bed..5cf5329e13a9 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -98,6 +98,7 @@ struct cxl_mbox_cmd {
*
* @dev: The device associated with this CXL state
* @regs: Parsed register blocks
+ * @cxl_dvsec: Offset to the PCIe device DVSEC
* @payload_size: Size of space for payload
* (CXL 2.0 8.2.8.4.3 Mailbox Capabilities Register)
* @lsa_size: Size of Label Storage Area
@@ -126,6 +127,7 @@ struct cxl_dev_state {
struct device *dev;
struct cxl_regs regs;
+ int cxl_dvsec;
size_t payload_size;
size_t lsa_size;
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index bf14c365ea33..c94002166084 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -408,6 +408,12 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
if (IS_ERR(cxlds))
return PTR_ERR(cxlds);
+ cxlds->cxl_dvsec = pci_find_dvsec_capability(
+ pdev, PCI_DVSEC_VENDOR_ID_CXL, CXL_DVSEC_PCIE_DEVICE);
+ if (!cxlds->cxl_dvsec)
+ dev_warn(&pdev->dev,
+ "Device DVSEC not present, skip CXL.mem init\n");
+
rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map);
if (rc)
return rc;
