imx: fec: add MAC reading from eFuses to README

Extend the documentation of the fec_mxc configuration by describing its
ability to read the ethaddr MAC address from the SoC eFuses.

Also add an example how to program the fuses for an imx5 to clarify the
byte order.

Cc: Stefano Babic <sbabic at denx.de>
Cc: Marek Vasut <marex at denx.de>
Signed-off-by: Olaf Mandel <o.mandel at menlosystems.com>

diff --git a/doc/README.fec_mxc b/doc/README.fec_mxc
index 72a1d595f5fe520bc252f5a71e0afd00a732f606..30e05da57455ba606e03a1b05fb36c7b151b08e0 100644 (file)
--- a/doc/README.fec_mxc
+++ b/doc/README.fec_mxc
@@ -1,7 +1,8 @@
 U-boot config options used in fec_mxc.c
 
 CONFIG_FEC_MXC
-       Selects fec_mxc.c to be compiled into u-boot.
+       Selects fec_mxc.c to be compiled into u-boot. Can read out the
+       ethaddr from the SoC eFuses (see below).
 
 CONFIG_MII
        Must be defined if CONFIG_FEC_MXC is defined.
@@ -25,3 +26,9 @@ CONFIG_FEC_MXC_NO_ANEG
 CONFIG_FEC_MXC_PHYADDR
        Optional, selects the exact phy address that should be connected
        and function fecmxc_initialize will try to initialize it.
+
+
+Reading the ethaddr from the SoC eFuses:
+if CONFIG_FEC_MXC is defined and the U-Boot environment does not contain the
+ethaddr variable, then its value gets read from the corresponding eFuses in
+the SoC. See the README files of the specific SoC for details.

diff --git a/doc/README.imx5 b/doc/README.imx5
index c5312b69d3598907d803b2dae71157094389da83..ea0e144cedcf2074a4752e8d1f03a7b9681ae78b 100644 (file)
--- a/doc/README.imx5
+++ b/doc/README.imx5
@@ -26,3 +26,15 @@ i.MX5x SoCs.
 
 2.1 MAC Address: It is stored in the words 9 to 14 of fuse bank 1, using the
     natural MAC byte order (i.e. MSB first).
+
+    This is an example how to program an example MAC address 01:23:45:67:89:ab
+    into the eFuses. Assure that the programming voltage is available and then
+    execute:
+
+    => fuse prog -y 1 9 01 23 45 67 89 ab
+
+    After programming a MAC address, consider locking the MAC fuses. This is
+    done by programming the MAC_ADDR_LOCK fuse, which is bit 4 of word 0 in
+    bank 1:
+
+    => fuse prog -y 1 0 10