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Diffstat (limited to 'doc/opal-api/opal-get-msi-39-40.txt')
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1 files changed, 46 insertions, 0 deletions
diff --git a/doc/opal-api/opal-get-msi-39-40.txt b/doc/opal-api/opal-get-msi-39-40.txt new file mode 100644 index 0000000..dbc809f --- /dev/null +++ b/doc/opal-api/opal-get-msi-39-40.txt @@ -0,0 +1,46 @@ +OPAL_GET_MSI_32 and OPAL_GET_MSI_64 +----------------------------------- + +#define OPAL_GET_MSI_32 39 +#define OPAL_GET_MSI_64 40 + +WARNING: following documentation is from old sources, and is possibly +not representative of OPALv3 as implemented by skiboot. This should be +used as a starting point for full documentation. + +OPAL PHBs encode MVE and XIVE specifiers in MSI DMA and message data values. +The host calls these functions to determine the PHB MSI DMA address and message +data to program into a PE PCIE function for a particular MVE and XIVE. The +msi_address parameter returns the MSI DMA address and the msi_data parameter +returns the MSI DMA message data value the PE uses to signal that interrupt. + + The phb_id parameter is the value from the PHB node ibm,opal-phbid + property. + + The mve_number is the index of an MVE used to authorize this PE to this + MSI. For ibm,opal-ioda2 PHBs, the MVE number argument is ignored. + + The xive_number is the index of an XIVE that corresponds to a particular + DMA address and message data value this PE will signal as an MSI ro MSI-X. + + The msi_range parameter specifies the number of MSIs associated with the + in put MVE and XIVE, primarily for MSI-conventional Multiple Message + Enable > 1 MSI. MSI requires consecutive MSIs per MSI address, and each + MSI DMA address must be unique for any given consecutive power of 2 set + of 32 message data values,. which in turn select particular PHB XIVEs. + This value must be a power of 2 value in the range of 0 to 32. OPAL + returns opal_parameter for values outside of this range. + +For MSI conventional, the MSI address and message data returned apply to a +power of 2 sequential set of XIVRs starting from the xive_number for the +power of 2 msi_range input argument. The message data returned represents the +power of 2 aligned starting message data value of the first interrupt number +in that sequential range. Valid msi_range input values are from 1 to 32. +Non-power of 2 values result in a return code of opal_PARAMETER . + +An msi_range value of 0 or 1 signifies that OPAL should return the message +data and message address for exactly one MSI specified by the input XIVE +number. For MSI conventional, the host should specify either a value of 0 or 1, +for an MSI Capability MME value of 1 MSI. For MSI-X XIVRs, the host should +specify a value of '1' for the msi_range argument and call this function for +each MSI-X uniquely. |