| 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. |
