FMC: add a software carrier driver

[karo-tx-linux.git] / Documentation / fmc / fmc-fakedev.txt

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+fmc-fakedev
+===========
+
+This package includes a software-only device, called fmc-fakedev, which
+is able to register up to 4 mezzanines (by default it registers one).
+Unlike the SPEC driver, which creates an FMC device for each PCI cards
+it manages, this module creates a single instance of its set of
+mezzanines.
+
+It is meant as the simplest possible example of how a driver should be
+written, and it includes a fake EEPROM image (built using the tools
+described in *note FMC Identification::),, which by default is
+replicated for each fake mezzanine.
+
+You can also use this device to verify the match algorithms, by asking
+it to test your own EEPROM image. You can provide the image by means of
+the eeprom= module parameter: the new EEPROM image is loaded, as usual,
+by means of the firmware loader.  This example shows the defaults and a
+custom EEPROM image:
+
+     spusa.root# insmod fmc-fakedev.ko
+     [   99.971247]  fake-fmc-carrier: mezzanine 0
+     [   99.975393]       Manufacturer: fake-vendor
+     [   99.979624]       Product name: fake-design-for-testing
+     spusa.root# rmmod fmc-fakedev
+     spusa.root# insmod fmc-fakedev.ko eeprom=fdelay-eeprom.bin
+     [  121.447464]  fake-fmc-carrier: Mezzanine 0: eeprom "fdelay-eeprom.bin"
+     [  121.462725]  fake-fmc-carrier: mezzanine 0
+     [  121.466858]       Manufacturer: CERN
+     [  121.470477]       Product name: FmcDelay1ns4cha
+     spusa.root# rmmod fmc-fakedev
+
+After loading the device, you can use the write_ee method do modify its
+own internal fake EEPROM: whenever the image is overwritten starting at
+offset 0, the module will unregister and register again the FMC device.
+This is shown in fmc-write-eeprom.txt