On 9/4/24 14:52, Bjorn Helgaas wrote: >> -#define PCI_TPH_CAP_ST_MASK 0x07FF0000 /* ST table mask */ >> -#define PCI_TPH_CAP_ST_SHIFT 16 /* ST table shift */ >> -#define PCI_TPH_BASE_SIZEOF 0xc /* size with no ST table */ >> +#define PCI_TPH_CAP_NO_ST 0x00000001 /* No ST Mode Supported */ >> +#define PCI_TPH_CAP_INT_VEC 0x00000002 /* Interrupt Vector Mode Supported */ >> +#define PCI_TPH_CAP_DEV_SPEC 0x00000004 /* Device Specific Mode Supported */ > > I think these modes should all include "ST" to clearly delineate > Steering Tags from the Processing Hints. E.g., > > PCI_TPH_CAP_ST_NO_ST or maybe PCI_TPH_CAP_ST_NONE Can I keep "NO_ST" instead of switching over to "ST_NONE"? First, it matches with PCIe spec. Secondly, IMO "ST_NONE" implies no ST support at all. > PCI_TPH_CAP_ST_INT_VEC > PCI_TPH_CAP_ST_DEV_SPEC Will change > >> +#define PCI_TPH_CAP_EXT_TPH 0x00000100 /* Ext TPH Requester Supported */ >> +#define PCI_TPH_CAP_LOC_MASK 0x00000600 /* ST Table Location */ >> +#define PCI_TPH_LOC_NONE 0x00000000 /* Not present */ >> +#define PCI_TPH_LOC_CAP 0x00000200 /* In capability */ >> +#define PCI_TPH_LOC_MSIX 0x00000400 /* In MSI-X */ > > These are existing symbols just being tidied, so can't really add "ST" > here unless we just add aliases. Since they're just used internally, > not by drivers, I think they're fine as-is. > Yes. In V1 review, Alex Williamson and Jonathan Cameron asked not to change these definitions as they might be used by existing software. >> +#define PCI_TPH_CAP_ST_MASK 0x07FF0000 /* ST Table Size */ >> +#define PCI_TPH_CAP_ST_SHIFT 16 /* ST Table Size shift */ >> +#define PCI_TPH_BASE_SIZEOF 0xc /* Size with no ST table */ >> + >> +#define PCI_TPH_CTRL 8 /* control register */ >> +#define PCI_TPH_CTRL_MODE_SEL_MASK 0x00000007 /* ST Mode Select */ >> +#define PCI_TPH_NO_ST_MODE 0x0 /* No ST Mode */ >> +#define PCI_TPH_INT_VEC_MODE 0x1 /* Interrupt Vector Mode */ >> +#define PCI_TPH_DEV_SPEC_MODE 0x2 /* Device Specific Mode */ > > These are also internal, but they're new and I think they should also > include "ST" to match the CAP #defines. > > Even better, maybe we only add these and use them for both CAP and > CTRL since they're defined with identical values. Can you elaborate here? In CTRL register, "ST Mode Select" is defined as a 2-bit field. The possible values are 0, 1, 2. But in CAP register, the modes are individual bit masked. So I cannot use CTRL definitions in CAP register directly unless I do shifting.
