Hi Lorenzo, Thank you for your review.
> -----Original Message----- > From: Lorenzo Pieralisi [mailto:lorenzo.pieral...@arm.com] > Sent: Wednesday, January 28, 2015 7:26 PM > To: Yang, Wenyou > Cc: Ferre, Nicolas; li...@arm.linux.org.uk; > linux-arm-ker...@lists.infradead.org; > linux-kernel@vger.kernel.org; alexandre.bell...@free-electrons.com; > sylvain.roc...@finsecur.com; p...@axentia.se; Vilchez, Patrice > Subject: Re: [PATCH 2/7] pm: at91: pm_suspend: add the WFI support for ARMv7 > > On Mon, Jan 26, 2015 at 10:06:01AM +0000, Wenyou Yang wrote: > > Commit log please. Added in the v2.0 > > > Signed-off-by: Wenyou Yang <wenyou.y...@atmel.com> > > --- > > arch/arm/mach-at91/pm_suspend.S | 54 > ++++++++++++++++++++++++++++++++++++++- > > 1 file changed, 53 insertions(+), 1 deletion(-) > > > > diff --git a/arch/arm/mach-at91/pm_suspend.S > > b/arch/arm/mach-at91/pm_suspend.S index 122a3f1..e796722 100644 > > --- a/arch/arm/mach-at91/pm_suspend.S > > +++ b/arch/arm/mach-at91/pm_suspend.S > > @@ -53,6 +53,58 @@ mode .req r6 > > beq 1b > > .endm > > > > +/* > > + * Put the processor to enter the WFI state */ > > + .macro _do_wfi > > You will have to explain why you need this, really. I don't understand your meaning. > > > + > > +#if defined(CONFIG_CPU_V7) > > + /* > > + * Execute an ISB instruction to flush the pipeline to ensure > > + * that all of operations have beem completed. > > s/beem/been Thanks. > > > + */ > > + isb > > + > > + /* > > + * Execute an ISB instruction to ensure that all of the > > + * CP15 register changes have been committed. > > + */ > > + dsb > > This is a dsb not an isb. Changed in the v2.0 > > > + dmb > > You have to explain why you need every single one of these barriers, > otherwise I > am NAKing this patch. No need this one? > > > + > > + /* Disable the processor's clock */ > > + mov tmp1, #AT91_PMC_PCK > > + str tmp1, [pmc, #AT91_PMC_SCDR] > > + > > + /* Execute a WFI instruction */ > > + wfi @ Wait For Interrupt > > This one looks ok :) > > > + > > + /* > > + * CPU can specualatively prefetch the instructions > > + * so add NOPs after WFI. Sixteen NOPs as Cortex-A5 pipeline. > > So what ? I suspect your issue is related to wfi completion on pending IRQ. I > would like to know the details that describe the issue you are trying to > solve here > please. Honestly, I referred to others, I will dig more, and test it. > > > + */ > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > + nop > > +#else > > + mcr p15, 0, tmp1, c7, c0, 4 > > +#endif > > Tell us what's the problem you have to solve, first, then we will see how to > fix it. > > Thanks, > Lorenzo > > > + > > + .endm > > + > > .text > > > > /* > > @@ -181,7 +233,7 @@ sdr_sr_done: > > > > skip_disable_main_clock: > > /* Wait for interrupt */ > > - mcr p15, 0, tmp1, c7, c0, 4 > > + _do_wfi > > > > tst mode, #AT91_PM_SLOW_CLOCK > > beq skip_enable_main_clock > > -- > > 1.7.9.5 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe > > linux-kernel" in the body of a message to majord...@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ > > Best Regards, Wenyou Yang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
