Re: [PATCH 1/1] nds32: Power management for nds32

From: Nick Hu
Date: Wed Oct 24 2018 - 05:39:55 EST


Hi Pavel,

On Wed, Oct 24, 2018 at 02:51:17PM +0800, Pavel Machek wrote:
> On Wed 2018-10-24 11:40:07, Nickhu wrote:
> > There are three sleep states in nds32:
> > suspend to idle,
> > suspend to standby,
> > suspend to ram
> >
> > In suspend to ram, we use the 'standby' instruction to emulate
> > power management device to hang the system util wakeup source
> > send wakeup events to break the loop.
> >
> > First, we push the general purpose registers and system registers
> > to stack. Second, we translate stack pointer to physical address
> > and store to memory to save the stack pointer. Third, after write
> > back and invalid the cache we hang in 'standby' intruction.
> > When wakeup source trigger wake up events, the loop will be break
> > and resume the system.
> >
> > Signed-off-by: Nickhu <nickhu@xxxxxxxxxxxxx>
>
> Is "Nickhu" complete name?
>
Oh, Nick Hu is my complete name.
I will fix it.
Thanks!

> > diff --git a/arch/nds32/kernel/pm.c b/arch/nds32/kernel/pm.c
> > new file mode 100644
> > index 000000000000..e1eaf3bac709
> > --- /dev/null
> > +++ b/arch/nds32/kernel/pm.c
> > @@ -0,0 +1,91 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +// Copyright (C) 2008-2017 Andes Technology Corporation
> > +
> > +/*
> > + * nds32 Power Management Routines
> > + *
> > + * This program is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU General Public License.
> > + *
> > + * Abstract:
> > + *
> > + * This program is for nds32 power management routines.
> > + *
> > + */
>
> I'd get rid of "abstract" here, repeating GPL twice and "nds32 power
> management routines" twice does not make much sense either.
>
Ok, I will get rid of it.

> > @@ -0,0 +1,129 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/* Copyright (C) 2017 Andes Technology Corporation */
> > +
> > +#include<asm/memory.h>
>
> Missing space.
>
> > +static int nointc_set_wake(struct irq_data *data, unsigned int on)
> > +{
> > + unsigned long int_mask = __nds32__mfsr(NDS32_SR_INT_MASK);
> > + static bool is_bit_1[NR_IRQS] = {false};
> > + u32 bit = 1 << data->hwirq;
> > +
> > + if (on) {
> > + if (int_mask & bit)
> > + is_bit_1[data->hwirq] = true;
> > + else
> > + is_bit_1[data->hwirq] = false;
> > +
> > + int_mask |= bit;
> > + wake_mask |= bit;
> > + } else {
> > + if (!is_bit_1[data->hwirq])
> > + int_mask &= ~bit;
> > +
> > + wake_mask &= ~bit;
> > + is_bit_1[data->hwirq] = false;
> > + }
>
> Can we get rid of "is_bit_1" array here, and use normal bit operations
> on another variable here?
>
Do you mean like this:

static int nointc_set_wake(struct irq_data *data, unsigned int on) {
unsigned long int_mask = __nds32__mfsr(NDS32_SR_INT_MASK);
static unsigned long irq_orig_bit = 0;
u32 bit = 1 << data->hwirq;

if (on) {
if (int_mask & bit)
__assign_bit(data->hwirq, &irq_orig_bit, true);
else
__assign_bit(data->hwirq, &irq_orig_bit, false);

__assign_bit(data->hwirq, &int_mask, true);
__assign_bit(data->hwirq, &wake_mask, true);

} else {
if (!(irq_orig_bit & bit))
__assign_bit(data->hwirq, &int_mask, false);

__assign_bit(data->hwirq, &wake_mask, false);
__assign_bit(data->hwirq, &irq_orig_bit, false);
}

__nds32__mtsr_dsb(int_mask, NDS32_SR_INT_MASK);

return 0;
}

> Thanks,
> Pavel
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Thank your for quick reply,
Nick Hu.