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authorSascha Hauer <s.hauer@pengutronix.de>2016-06-07 22:16:48 +0200
committerSascha Hauer <s.hauer@pengutronix.de>2016-07-06 10:09:29 +0200
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Introduce non volatile device variables
Non volatile device variables are used to make device parameters persistent. They are like normal non volatile variables, but set the values of the device parameters with the corresponding name. Every nv variable beginning with nv.dev is a non volatile device variable. They have the form nv.dev.<devname>.<paramname> and act on the parameter <paramname> of the device named <devname>. The non volatile device variables are designated for example for video modes, ethernet device ip addresses or mtd partitioning. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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@@ -66,6 +66,24 @@ examples:
model: myboard
barebox@yourboard:/
+Non volatile device variables
+-----------------------------
+
+Non volatile device variables are used to make device parameters persistent. They
+are regular nv variables but are linked with other devices instead of the global
+device. Every nv variable in the form nv.dev.<devname>.<paramname> will be mirrored
+to the corresponding <devname>.<paramname> variable.
+
+This example changes the partitioning of the nand0 device:
+
+.. code-block:: sh
+ barebox@Phytec phyCARD-i.MX27:/ nv dev.nand0.partitions: 4M(barebox),1M(barebox-environment),-(root)
+ barebox@Phytec phyCARD-i.MX27:/ devinfo nand0
+ Parameters:
+ [...]
+ partitions: 4M(barebox),1M(barebox-environment),8M(kernel),1011M(root)
+ [...]
+
.. _magicvars:
Magic variables