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>> + >> + if (!(cap & PCI_DVSEC_CXL_CACHE_CAPABLE) || >> + !(cap & PCI_DVSEC_CXL_MEM_CAPABLE)) > Why do we need them both? Sure that's type 2, but a non > class code matching type3 would I think need the same infrastructure > you are building here. That would have cxl.mem but not cxl.cache > - I think some of the CXL SSD prototypes fit in this category. Not sure if this reset path requires only Type2, but see my related comment below. >> + return -ENOTTY; >> + >> + if (!(cap & PCI_DVSEC_CXL_RST_CAPABLE)) >> + return -ENOTTY; >> + if (!(cap & PCI_DVSEC_CXL_RST_MEM_CLR_CAPABLE)) >> + return -ENOTTY; >> + >> + rc = pci_read_config_word(pdev, dvsec + PCI_DVSEC_CXL_CTRL, &ctrl); >> + if (rc) >> + return pcibios_err_to_errno(rc); >> + >> + if (!(ctrl & PCI_DVSEC_CXL_CACHE_ENABLE) || >> + !(ctrl & PCI_DVSEC_CXL_MEM_ENABLE)) >> + return -ENOTTY; Type2 cache support is coming and it could be CXL.cache forced to disable if IOMMU enabled and the device not supporting ATS nor belonging to IOMMU identity mapping (Benjamin Cheatham will send this support soon). In that case, I can not see a reason for not allowing a reset assuming CXL.mem would be still usable independently of CXL.cache functionality.