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SAMA5D4-EK: NSH should run at 528MHz

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This commit is contained in:
Gregory Nutt 2014-07-02 15:31:52 -06:00
parent 6c3f159e5f
commit c42a44be72
2 changed files with 6 additions and 28 deletions
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30
configs/sama5d4-ek/README.txt
View File

@ -1760,11 +1760,6 @@ USB High-Speed Host
Application Configuration -> NSH Library
CONFIG_NSH_ARCHINIT=y : NSH board-initialization
NOTE: When OHCI is selected, the SAMA5 will operate at 384MHz instead of
396MHz. This is so that the PLL generates a frequency which is a multiple
of the 48MHz needed for OHCI. The delay loop calibration values that are
used will be off slightly because of this.
EHCI
----
@ -3023,29 +3018,12 @@ Configurations
create a very corrupt configuration that may not be easy to recover
from.
4. The SAMA5Dx is running at 396MHz by default in these configurations.
This is because the original timing for the PLLs, NOR FLASH, and SDRAM
came from the Atmel NoOS sample code which runs at that rate.
The SAMA5Dx is capable of running at 528MHz, however, and is easily
re-configured:
4. The SAMA5Dx is running at 528MHz by default in these configurations.
Board Selection -> CPU Frequency
CONFIG_SAMA5D4EK_396MHZ=n # Disable 396MHz operation
CONFIG_SAMA5D4EK_528MHZ=y # Enable 528MHz operation
If you switch to 528MHz, you should also check the loop calibration
value in your .config file. Of course, it would be best to re-calibrate
the timing loop, but these values should get you in the ballpark:
CONFIG_BOARD_LOOPSPERMSEC=49341 # Calibrated on SAMA5D3-EK at 396MHz
# running from ISRAM
CONFIG_BOARD_LOOPSPERMSEC=65775 # Calibrated on SAMA5D3-Xplained at
# 528MHz running from SDRAM
Operation at 528MHz has been verified but is not the default in these
configurations because most testing was done at 396MHz. NAND has not
been verified at these rates.
CONFIG_SAMA5D4EK_528MHZ=y : Enable 528MHz operation
CONFIG_BOARD_LOOPSPERMSEC=65775 : Calibrated on SAMA5D3-Xplained at
: 528MHz running from SDRAM
Configuration Sub-directories
-----------------------------

4
configs/sama5d4-ek/nsh/defconfig
View File

@ -351,8 +351,8 @@ CONFIG_NSH_MMCSDSLOTNO=0
# Board-Specific Options
#
# CONFIG_SAMA5D4EK_384MHZ is not set
CONFIG_SAMA5D4EK_396MHZ=y
# CONFIG_SAMA5D4EK_528MHZ is not set
# CONFIG_SAMA5D4EK_396MHZ is not set
CONFIG_SAMA5D4EK_528MHZ=y
CONFIG_SAMA5D4EK_DRAM_BOOT=y
#