Hi,
The 'DDR memory controller' allows us to choose the 'power management mode'.
In the 'QorIQ LS1028A Reference Manual', I read the 'dynamic power management mode' can reduce power consomption.
My first question is:
does this mode reduce the DDR refresh rate, and is there an impact about the performances?
My second question is how to active this 'power management mode'? Is there a regsiter to write in it, at which step of the boot (with the PreBoot Loader ?)?
Thanks for your help.
Regards,
Solved! Go to Solution.
1. When dynamic power management mode is enabled, it puts SDRAM devices into power-down mode when there is no ongoing memory activity by negating CKE signal. Details of 'power-down mode' can be found in SDRAM datasheets.
When the memory exits from the power-down mode, it requires some time delay (tXP) before any bus command (like read/write), so yes, this mode slightly affects performance.
2. To enable dynamic power management mode the user should set bit DDR_SDRAM_CFG[DYN_PWR]. This can be done any time, for example before the DDR controller is enabled.
Regards,
Bulat
1. When dynamic power management mode is enabled, it puts SDRAM devices into power-down mode when there is no ongoing memory activity by negating CKE signal. Details of 'power-down mode' can be found in SDRAM datasheets.
When the memory exits from the power-down mode, it requires some time delay (tXP) before any bus command (like read/write), so yes, this mode slightly affects performance.
2. To enable dynamic power management mode the user should set bit DDR_SDRAM_CFG[DYN_PWR]. This can be done any time, for example before the DDR controller is enabled.
Regards,
Bulat