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702e6014f1
Also drop a few files referring to no longer / not yet supported boards. Signed-off-by: Wolfgang Denk <wd@denx.de> Cc: Prafulla Wadaskar <prafulla@marvell.com> Cc: Stefan Roese <sr@denx.de> Cc: Kim Phillips <kim.phillips@freescale.com> Cc: Andy Fleming <afleming@gmail.com> Cc: Jason Jin <jason.jin@freescale.com> Cc: Stefano Babic <sbabic@denx.de> Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com> Acked-by: Stefano Babic <sbabic@denx.de> Acked-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
22 lines
942 B
Text
22 lines
942 B
Text
Lite5200B wakeup from low-power mode (CONFIG_LITE5200B_PM)
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Low-power mode as described in Lite5200B User's Manual, means that
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with support of MC68HLC908QT1 microcontroller (refered to as QT),
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everything but the SDRAM can be powered down. This brings
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maximum power saving, while one can still restore previous state
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quickly.
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Quick overview where U-Boot comes into the picture:
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- OS saves device states
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- OS saves wakeup handler address to physical 0x0, puts SDRAM into
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self-refresh and signals to QT, it should power down the board
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- / board is sleeping here /
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- someone presses SW4 (connected to QT)
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- U-Boot checks PSC2_4 pin, if QT drives it down, then we woke up,
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so get SDRAM out of self-refresh and transfer control to OS
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wakeup handler
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- OS restores device states
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This was tested on Linux with USB and Ethernet in use. Adding
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support for other devices is an OS issue.
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