Hi, On OMAP4, the PRCM recommended sequence for enabling a module after power-on-reset is -1- Force clkdm to SW_WKUP -2- Configure desired module mode to "enable" or "auto" -3- Wait for the desired module idle status to be FUNC -4- Program clkdm in HW_AUTO(if supported) This sequence applies to all older OMAPs' as well, however since they use 'autodeps', it makes sure that no clkdm is in IDLE, and hence not requiring a force SW_WKUP when a module is being enabled. OMAP4 does not need to support autodeps, because of the dynamic dependency feature, wherein the HW takes care of waking up a clockdomain from idle and hence the module, whenever an interconnect access happens to the given module. Implementing the sequence for OMAP4 requires some of the clockdomain handling that is currently done in clock framework to be done as part of hwmod framework since the step -3- above to "Wait for the desired module idle status to be FUNC" is done as part of hwmod framework. This series moves the clockdomain handling into hwmod framework and implements the above sequence for OMAP4. The above sequence is expected to be followed even for optional clocks (steps -1-, -2- and -4- only) and that makes handling it difficult as optional clocks are enabled by drivers using direct clock framework calls and hence do not go through the hwmod framework. Hence this series also adds the handling of the sequence *only for optional clocks* in clock framework. Lastly, with this series drivers which are yet to be adapted to PM runtime and still rely on clock calls to enable/disable the respective *main* clocks are expected to be broken. MMC is one such which even breaks boot, and hence the series has a TEMP workaround patch added which keeps l3init clockdomain always force-enabled. This TEMP patch will gate all CORE low power transitions but should atleast allow MPU low power transitions to work. The series is tested for low power state transitions (RET/OFF) on OMAP3sdp and boot tested on OMAP4sdp. Applies on 3.0-rc2 Rajendra Nayak (8): OMAP2+: clockdomain: Add an api to read idle mode OMAP2+: clockdomain: Add SoC support for clkdm_is_idle OMAP2+: PM: Initialise sleep_switch to a non-valid value OMAP2+: PM: idle clkdms only if already in idle OMAP4: PM: TEMP: Prevent l3init from idling/force sleep OMAP2+: hwmod: Follow the recomended PRCM clock enable sequence OMAP: clock: Add flags to identify optional clock nodes OMAP: clock: Enable clockdomain only for optional clocks arch/arm/mach-omap2/clock.c | 30 ++++++++++++------------ arch/arm/mach-omap2/clock44xx_data.c | 34 +++++++++++++++++++++++++++ arch/arm/mach-omap2/clockdomain.c | 28 +++++++++++++++++++++- arch/arm/mach-omap2/clockdomain.h | 3 ++ arch/arm/mach-omap2/clockdomain2xxx_3xxx.c | 12 +++++++++ arch/arm/mach-omap2/clockdomain44xx.c | 16 ++++++------ arch/arm/mach-omap2/clockdomains44xx_data.c | 2 +- arch/arm/mach-omap2/omap_hwmod.c | 20 +++++++++++++++- arch/arm/mach-omap2/pm.c | 6 +++- arch/arm/plat-omap/include/plat/clock.h | 1 + 10 files changed, 124 insertions(+), 28 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
