SetupDesignGuide.pdf - Firmware Encoding Index

Setup Design Guide
DRAFT
This keyword is used primarily when defining flags settings for certain operations. This keyword will
primarily be used if a particular operation requires additional information from a hardware specific
interface. The intention is that once the data is retrieved successfully, the bit will internally be turned
off and a callback will not be done again. When doing a callback, a key will be passed to the driver
who exported this data. The driver interprets the key and returns the appropriate data in an appropriate
form. The compiler will ensure the key value specified is unique across the entire formset.
A common scenario where this might be used is when a text op-code which prints CPU information is
used and needs to print information like the CPU frequency. This obviously could not have been
determined during the building of the VFR file.
Example: text text = STR_CPU_FREQUENCY_TEXT,
text = STR_CPU_DERIVED_TEXT,
flags = DYNAMIC,
key = CPU_FREQUENCY_KEY;
More information about interacting with hardware is contained in section 2.6.
4.3.4 INTERACTIVE
**Limit to one-of, text, and string, and numeric – any reason for other op-codes to be of this
class?**
This keyword is used primarily when defining flags settings for certain operations. This keyword will
primarily be used if a particular operation requires additional information from a hardware specific
interface. The intention is that once the initial data is retrieved successfully, the DYNAMIC bit will
internally be disabled. This assumes that the infrastructure now has sufficient data to display initial
data to the screen.
The INTERACTIVE flag is not compatible with exporting data to runtime since it assumes callbacks to
a driver which may not exist in the O/S runtime space. The use of this flag should be relegated to preboot
only utilities.
Once a user makes a selection on a tag that is interactive, a callback will be made to retrieve the data
from a driver. A common use for this flag might be the entering of a modem configuration string, and
returning data based on the resulting status from the modem.
Example: string
endstring;
varid = NULL.ModemString,
prompt = STR_MODEM_STRING_PROMPT,
help = STR_MODEM_STRING_HELP,
minsize = 1,
maxsize = 60,
flags = INTERACTIVE,
key = MODEM_STRING_KEY,
In the above example, a user would select the modem string prompt. After typing in the modem string
to send to the modem (i.e. ATE1M0), a callback to the driver would send this packet of data to the
modem. The modem will give some return code to the called driver. The driver will return back to the
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