On Thu, 2013-05-16 at 07:11 +0800, Stephen Warren wrote: > On 05/15/2013 04:27 AM, Joseph Lo wrote: > > The Tegra114 is a quad cores SoC. Each core can be hotplugged including > > CPU0. The hotplug sequence can be controlled by setting event trigger in > > flow controller. Then the flow controller will take care all the power > > sequence that include CPU up and down. > > > diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile > > > +obj-$(CONFIG_ARCH_TEGRA_114_SOC) += sleep-tegra30.o > > CONFIG_ARCH_TEGRA_3x_SOC also adds that to obj-y. Will including it > twice cause problems? > Looks the compiler can take care of this. I didn't see any problem here.
> > diff --git a/arch/arm/mach-tegra/reset-handler.S > > b/arch/arm/mach-tegra/reset-handler.S > > > * CPU boot vector when restarting the a CPU following > > * an LP2 transition. Also branched to by LP0 and LP1 resume after > > * re-enabling sdram. > > + * > > + * r6: SoC ID << 8 > > I meant to ask in patch 1: Perhaps the macro could do a >>8 so that code > can compare directly against the SoC IDs instead of having to compare > against shifted values. > That's more easy to read the code indeed. Will do. > > + tegra_check_soc_id TEGRA114, TEGRA_APB_MISC_BASE, r6, r7 > > + beq no_cpu0_chk > > Does that need a THUMB(it ...) added? Same elsewhere. > Will double confirm again later. > > + cmp r6, #(TEGRA114 <<8) > > Needs a space after <<. > > > diff --git a/arch/arm/mach-tegra/sleep-tegra30.S > > b/arch/arm/mach-tegra/sleep-tegra30.S > > > @@ -45,12 +46,17 @@ ENDPROC(tegra30_hotplug_shutdown) > > * and powergates it -- flags (in R0) indicate the request type. > > * Must never be called for CPU 0. > > That comment is wrong now, I think. Only true for Tegra30 now. Will fix. > > > tst r0, #TEGRA30_POWER_HOTPLUG_SHUTDOWN > > + beq flow_ctrl_setting_for_lp2 > > + > > + /* flow controller set up for hotplug */ > > + mov r3, #FLOW_CTRL_WAITEVENT @ For hotplug > > + b flow_ctrl_done > > +flow_ctrl_setting_for_lp2: > > + /* flow controller set up for LP2 */ > > + cmp r10, #(TEGRA30 << 8) > > moveq r3, #FLOW_CTRL_WAIT_FOR_INTERRUPT @ For LP2 > > Do you need e.g. "movne r3, #0" or similar here? Otherwise, I think r3 > ends up not being initialized. Yes, I will add the code when I add LP2 support for Tegra114 later. Currently the LP2 code flow only for Tegra30, so it's OK. > > > - movne r3, #FLOW_CTRL_WAITEVENT @ For hotplug > > +flow_ctrl_done: > > + cmp r10, #(TEGRA30 << 8) > > str r3, [r2] > > I wonder whether creating a separate tegra114_cpu_shutdown() wouldn't be > better, to avoid all the runtime conditional code. I personally think the conditional code is OK. And the ARM CPU also had hardware for branch detection also. I had finished some further features for both Tegra30 and Tegra114. And most of the code here can be shared each other at least until now I could see. Once I see if there is a significant difference, then I would prepare maintain the code separately too. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
