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diff --git a/doc/README.imx31 b/doc/README.imx31 new file mode 100644 index 0000000000..91ef766884 --- /dev/null +++ b/doc/README.imx31 @@ -0,0 +1,29 @@ +U-Boot for Freescale i.MX31 + +This file contains information for the port of U-Boot to the Freescale +i.MX31 SoC. + +1. CONFIGURATION OPTIONS/SETTINGS +--------------------------------- + +1.1 Configuration of MC13783 SPI bus +------------------------------------ + The power management companion chip MC13783 is connected to the + i.MX31 via an SPI bus. Use the following configuration options + to setup the bus and chip select used for a particular board. + + CONFIG_MC13783_SPI_BUS -- defines the SPI bus the MC13783 is connected to. + Note that 0 is CSPI1, 1 is CSPI2 and 2 is CSPI3. + CONFIG_MC13783_SPI_CS -- define the chip select the MC13783 s connected to. + +1.2 Timer precision +------------------- + CONFIG_MX31_TIMER_HIGH_PRECISION + + Enable higher precision timer. The low-precision timer + (default) provides approximately 4% error, whereas the + high-precision timer is about 0.4% accurate. The extra + accuracy is achieved at the cost of higher computational + overhead, which, in places where time is measured, should + not be critical, so, it should be safe to enable this + option. |