From 06e279e5ebe4f32ffe544ec96a199870319a7315 Mon Sep 17 00:00:00 2001 From: Ben Widawsky Date: Tue, 1 Feb 2022 14:06:32 -0800 Subject: cxl/pci: Cache device DVSEC offset 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 Reviewed-by: Jonathan Cameron Link: https://lore.kernel.org/r/164375309615.513620.7874131241128599893.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams --- drivers/cxl/cxlmem.h | 2 ++ drivers/cxl/pci.c | 6 ++++++ 2 files changed, 8 insertions(+) (limited to 'drivers/cxl') 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; -- cgit v1.2.3-59-g8ed1b