Hi Markus, On 03/09/19 16:04, Markus Armbruster wrote: > The subject "Add QMP 'info fw_cfg' command" misspells query-fw_cfg-items > :) > > Eric Blake <ebl...@redhat.com> writes: > >> On 3/7/19 7:32 PM, Philippe Mathieu-Daudé wrote:
>>> +## >>> +# @FirmwareConfigurationItem: >>> +# >>> +# Firmware Configuration (fw_cfg) item. >>> +# >>> +# @key: The uint16 selector key. >>> +# @keyname: The stringified name if the selector refers to a well-known >>> +# numerically defined item. > > Ignorant questions, I'm afraid... > > What determines the possible values of @key? the text file "docs/specs/fw_cfg.txt" explains this somewhat. - In section "Selector (Control) Register", it lays out the structure of the key space. > What's the difference between a "well-known" and a "not well-known" > value? Examples? - In section "Firmware Configuration Items", it explains the selectors FW_CFG_SIGNATURE, FW_CFG_ID, FW_CFG_FILE_DIR. - Then it "implies" readers should consult "include/standard-headers/linux/qemu_fw_cfg.h". :) All in all, a selector is "well known" if the QEMU source code defines -- perhaps through incorporating a kernel include file -- a macro directly for the numeric value of the selector key. Such a selector is "well known" because guest firmware is allowed / required to refer directly to the numeric value, rather than to look it up in the fw_cfg file directory, by name (such as "etc/table-loader", "bootorder", ...). Thanks! Laszlo
