Hi Santosh, Benoit, On 05/10/2012 01:54 AM, Santosh Shilimkar wrote: > On Thursday 10 May 2012 03:06 AM, Jon Hunter wrote: >> From: Jon Hunter <[email protected]> >> >> 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. 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 > Not sure if this can be entirely correct for OMAP4. > Because HW_AUTO = "Sleep and wakeup transition are > based upon hardware conditions" > Where as SW_SLEEP = "Start a software forced sleep > transition on the domain." > > I will reply on the the thread where this is being discussed.
Given that feedback we received that the only difference between HW_AUTO and SW_SLEEP 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". Are you ok with this change? If so can you sign-off on this? I can update the series with all the comments and re-post this week. Cheers Jon -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
