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+U-Boot for Freescale i.MX5x
+
+This file contains information for the port of U-Boot to the Freescale
+i.MX5x SoCs.
+
+1. CONFIGURATION OPTIONS/SETTINGS
+---------------------------------
+
+1.1 CONFIG_MX51_PLL_ERRATA: Workaround for i.MX51 PLL errata.
+ This option should be enabled by all boards using the i.MX51 silicon
+ version up until (including) 3.0 running at 800MHz.
+ The PLL's in the i.MX51 processor can go out of lock due to a metastable
+ condition in an analog flip-flop when used at high frequencies.
+ This workaround implements an undocumented feature in the PLL (dither
+ mode), which causes the effect of this failure to be much lower (in terms
+ of frequency deviation), avoiding system failure, or at least decreasing
+ the likelihood of system failure.
+
+1.2 CONFIG_SYS_MAIN_PWR_ON: Trigger MAIN_PWR_ON upon startup.
+ This option should be enabled for boards having a SYS_ON_OFF_CTL signal
+ connected to GPIO1[23] and triggering the MAIN_PWR_ON signal like in the
+ reference designs.
+
+2. CONVENTIONS FOR FUSE ASSIGNMENTS
+-----------------------------------
+
+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