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Diffstat (limited to 'qemu/roms/u-boot/doc/README.imx5')
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diff --git a/qemu/roms/u-boot/doc/README.imx5 b/qemu/roms/u-boot/doc/README.imx5 new file mode 100644 index 000000000..c5312b69d --- /dev/null +++ b/qemu/roms/u-boot/doc/README.imx5 @@ -0,0 +1,28 @@ +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). |