ARM: OMAP4: clockdomain/CM code: Update supported transition modes
For OMAP3+ devices, the clock domains (CLKDMs) support one or more of the
following transition modes ...
NO_SLEEP (0x0) - A clock domain sleep transition is never initiated,
irrespective of the hardware conditions.
SW_SLEEP (0x1) - A software-forced sleep transition. The transition is initiated
when the associated hardware conditions are satisfied
SW_WKUP (0x2) - A software-forced clock domain wake-up transition is initiated,
irrespective of the hardware conditions.
HW_AUTO (0x3) - Hardware-controlled automatic sleep and wake-up transition is
initiated by the PRCM module when the associated hardware
conditions are satisfied.
For OMAP4 devices, SW_SLEEP is equivalent to HW_AUTO and NO_SLEEP is equivalent
to SW_WKUP. The only difference between HW_AUTO and SW_SLEEP for OMAP4 devices
is that the PRM_IRQSTATUS_MPU.TRANSITION_ST interrupt status is set in case of
SW_SLEEP transition, and not set in case of HW_AUTO transition.
For OMAP4 devices, all CLKDMs support HW_AUTO and therefore we can place the
CLKDMs in the HW_AUTO state instead of the SW_SLEEP mode. Hence, we do not
need to use the SW_SLEEP mode. With regard to NO_SLEEP and SW_WKUP it is
preferred to use SW_WKUP mode if the CLKDM supports it and so use this mode
instead of NO_SLEEP where possible.
For a software perspective the above 4 modes are represented by the following
flags to indicate what modes are supported by each of the CLKDMs.
CLKDM_CAN_DISABLE_AUTO --> NO_SLEEP
CLKDM_CAN_ENABLE_AUTO --> HW_AUTO
CLKDM_CAN_FORCE_SLEEP --> SW_SLEEP
CLKDM_CAN_FORCE_WAKEUP --> SW_WKUP
By eliminating the SW_SLEEP mode the the mapping of the flags for OMAP4 devices
can becomes ...
CLKDM_CAN_DISABLE_AUTO --> NO_SLEEP
CLKDM_CAN_ENABLE_AUTO --> HW_AUTO
CLKDM_CAN_FORCE_SLEEP --> HW_AUTO
CLKDM_CAN_FORCE_WAKEUP --> SW_WKUP
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
2 files changed