mirror of
https://github.com/AsahiLinux/u-boot
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30 lines
1.1 KiB
Text
30 lines
1.1 KiB
Text
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U-Boot for Freescale i.MX31
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This file contains information for the port of U-Boot to the Freescale
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i.MX31 SoC.
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1. CONFIGURATION OPTIONS/SETTINGS
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---------------------------------
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1.1 Configuration of MC13783 SPI bus
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------------------------------------
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The power management companion chip MC13783 is connected to the
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i.MX31 via an SPI bus. Use the following configuration options
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to setup the bus and chip select used for a particular board.
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CONFIG_MC13783_SPI_BUS -- defines the SPI bus the MC13783 is connected to.
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Note that 0 is CSPI1, 1 is CSPI2 and 2 is CSPI3.
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CONFIG_MC13783_SPI_CS -- define the chip select the MC13783 s connected to.
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1.2 Timer precision
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-------------------
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CONFIG_MX31_TIMER_HIGH_PRECISION
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Enable higher precision timer. The low-precision timer
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(default) provides approximately 4% error, whereas the
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high-precision timer is about 0.4% accurate. The extra
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accuracy is achieved at the cost of higher computational
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overhead, which, in places where time is measured, should
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not be critical, so, it should be safe to enable this
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option.
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