xref: /rk3399_rockchip-uboot/doc/README.imx5 (revision 98a48c5de545e5a5eedba0a868024ef0d4ae5347)
1U-Boot for Freescale i.MX5x
2
3This file contains information for the port of U-Boot to the Freescale
4i.MX5x SoCs.
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61. CONFIGURATION OPTIONS/SETTINGS
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91.1 CONFIG_MX51_PLL_ERRATA: Workaround for i.MX51 PLL errata.
10    This option should be enabled by all boards using the i.MX51 silicon
11    version up until (including) 3.0 running at 800MHz.
12    The PLL's in the i.MX51 processor can go out of lock due to a metastable
13    condition in an analog flip-flop when used at high frequencies.
14    This workaround implements an undocumented feature in the PLL (dither
15    mode), which causes the effect of this failure to be much lower (in terms
16    of frequency deviation), avoiding system failure, or at least decreasing
17    the likelihood of system failure.
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