Benoit Cousson <[email protected]> writes: > From: Rajendra Nayak <[email protected]> > > On OMAP4, the PRCM recommended sequence for enabling > a module after power-on-reset is: > -1- Force clkdm to SW_WKUP > -2- Enabling the clocks > -3- Configure desired module mode to "enable" or "auto" > -4- Wait for the desired module idle status to be FUNC > -5- 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.
OK, I found the problem that prevents booting on OMAP3... > OMAP4 does not need to support autodeps, because > of the dyanamic 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 > the clockdomain handling that is currently done in > clock framework to be done as part of hwmod framework > since the step -4- above to "Wait for the desired > module idle status to be FUNC" is done as part of > hwmod framework. > > Signed-off-by: Rajendra Nayak <[email protected]> > [[email protected]: Adapt it to the new clkdm hwmod attribute and API] > Signed-off-by: Benoit Cousson <[email protected]> > Cc: Paul Walmsley <[email protected]> > --- > arch/arm/mach-omap2/clock.c | 17 +---------------- > arch/arm/mach-omap2/omap_hwmod.c | 26 +++++++++++++++++++++++++- > 2 files changed, 26 insertions(+), 17 deletions(-) > > diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c > index 180299e..2828d29 100644 > --- a/arch/arm/mach-omap2/clock.c > +++ b/arch/arm/mach-omap2/clock.c > @@ -268,9 +268,6 @@ void omap2_clk_disable(struct clk *clk) > clk->ops->disable(clk); > } > > - if (clk->clkdm) > - clkdm_clk_disable(clk->clkdm, clk); > - > if (clk->parent) > omap2_clk_disable(clk->parent); > } > @@ -308,30 +305,18 @@ int omap2_clk_enable(struct clk *clk) > } > } > > - if (clk->clkdm) { > - ret = clkdm_clk_enable(clk->clkdm, clk); > - if (ret) { > - WARN(1, "clock: %s: could not enable clockdomain %s: " > - "%d\n", clk->name, clk->clkdm->name, ret); > - goto oce_err2; > - } > - } > - > if (clk->ops && clk->ops->enable) { > trace_clock_enable(clk->name, 1, smp_processor_id()); > ret = clk->ops->enable(clk); > if (ret) { > WARN(1, "clock: %s: could not enable: %d\n", > clk->name, ret); > - goto oce_err3; > + goto oce_err2; > } > } The clkdm enable/disable in this part of the patch is still required on OMAP2/3, since the clkdm is still attached to the clock and not to the hwmod. Just backing out the mach-omap2/clock.c changes from this patch allows this series to boot fine on OMAP3. Kevin -- 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
