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Jean-Christophe PLAGNIOL-VILLARD77a03552008-09-30 20:08:36 +02001U-Boot for Freescale i.MX31
2
3This file contains information for the port of U-Boot to the Freescale
4i.MX31 SoC.
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61. CONFIGURATION OPTIONS/SETTINGS
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8
91.1 Configuration of MC13783 SPI bus
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11 The power management companion chip MC13783 is connected to the
12 i.MX31 via an SPI bus. Use the following configuration options
13 to setup the bus and chip select used for a particular board.
14
15 CONFIG_MC13783_SPI_BUS -- defines the SPI bus the MC13783 is connected to.
16 Note that 0 is CSPI1, 1 is CSPI2 and 2 is CSPI3.
17 CONFIG_MC13783_SPI_CS -- define the chip select the MC13783 s connected to.
18
191.2 Timer precision
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21 CONFIG_MX31_TIMER_HIGH_PRECISION
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23 Enable higher precision timer. The low-precision timer
24 (default) provides approximately 4% error, whereas the
25 high-precision timer is about 0.4% accurate. The extra
26 accuracy is achieved at the cost of higher computational
27 overhead, which, in places where time is measured, should
28 not be critical, so, it should be safe to enable this
29 option.