* [PATCH] net: stmmac: disable/enable ptp_ref_clk in suspend/resume flow
@ 2019-10-09 8:56 Biao Huang
2019-10-10 23:01 ` Jakub Kicinski
0 siblings, 1 reply; 3+ messages in thread
From: Biao Huang @ 2019-10-09 8:56 UTC (permalink / raw)
To: davem, Jose Abreu, andrew
Cc: Giuseppe Cavallaro, Alexandre Torgue, Maxime Coquelin,
Matthias Brugger, netdev, linux-stm32, linux-arm-kernel,
linux-kernel, linux-mediatek, yt.shen, biao.huang, jianguo.zhang,
boon.leong.ong
disable ptp_ref_clk in suspend flow, and enable it in resume flow.
Signed-off-by: Biao Huang <biao.huang@mediatek.com>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index c7c9e5f162e6..b592aeecc3dd 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -4469,6 +4469,8 @@ int stmmac_suspend(struct device *dev)
stmmac_mac_set(priv, priv->ioaddr, false);
pinctrl_pm_select_sleep_state(priv->device);
/* Disable clock in case of PWM is off */
+ if (priv->plat->clk_ptp_ref)
+ clk_disable_unprepare(priv->plat->clk_ptp_ref);
clk_disable(priv->plat->pclk);
clk_disable(priv->plat->stmmac_clk);
}
@@ -4535,6 +4537,8 @@ int stmmac_resume(struct device *dev)
/* enable the clk previously disabled */
clk_enable(priv->plat->stmmac_clk);
clk_enable(priv->plat->pclk);
+ if (priv->plat->clk_ptp_ref)
+ clk_prepare_enable(priv->plat->clk_ptp_ref);
/* reset the phy so that it's ready */
if (priv->mii)
stmmac_mdio_reset(priv->mii);
--
2.18.0
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] net: stmmac: disable/enable ptp_ref_clk in suspend/resume flow
2019-10-09 8:56 [PATCH] net: stmmac: disable/enable ptp_ref_clk in suspend/resume flow Biao Huang
@ 2019-10-10 23:01 ` Jakub Kicinski
2019-10-11 8:21 ` biao huang
0 siblings, 1 reply; 3+ messages in thread
From: Jakub Kicinski @ 2019-10-10 23:01 UTC (permalink / raw)
To: Biao Huang
Cc: davem, Jose Abreu, andrew, Giuseppe Cavallaro, Alexandre Torgue,
Maxime Coquelin, Matthias Brugger, netdev, linux-stm32,
linux-arm-kernel, linux-kernel, linux-mediatek, yt.shen,
jianguo.zhang, boon.leong.ong
On Wed, 9 Oct 2019 16:56:49 +0800, Biao Huang wrote:
> disable ptp_ref_clk in suspend flow, and enable it in resume flow.
>
> Signed-off-by: Biao Huang <biao.huang@mediatek.com>
> ---
> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index c7c9e5f162e6..b592aeecc3dd 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -4469,6 +4469,8 @@ int stmmac_suspend(struct device *dev)
> stmmac_mac_set(priv, priv->ioaddr, false);
> pinctrl_pm_select_sleep_state(priv->device);
> /* Disable clock in case of PWM is off */
> + if (priv->plat->clk_ptp_ref)
> + clk_disable_unprepare(priv->plat->clk_ptp_ref);
I don't know much embedded, but it seems like this should perhaps just
be clk_disable() without the unprepare? stmmac_hw_teardown() is called
when driver is removed so it needs to unprepare as well.
Please feel free to explain to me why this needs to be
clk_disable_unprepare(), as I said - not an expert.
Also - if this is a bug fix and you'd like to have it backported to
older releases you need to add a Fixes tag.
Thanks!
> clk_disable(priv->plat->pclk);
> clk_disable(priv->plat->stmmac_clk);
> }
> @@ -4535,6 +4537,8 @@ int stmmac_resume(struct device *dev)
> /* enable the clk previously disabled */
> clk_enable(priv->plat->stmmac_clk);
> clk_enable(priv->plat->pclk);
> + if (priv->plat->clk_ptp_ref)
> + clk_prepare_enable(priv->plat->clk_ptp_ref);
> /* reset the phy so that it's ready */
> if (priv->mii)
> stmmac_mdio_reset(priv->mii);
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] net: stmmac: disable/enable ptp_ref_clk in suspend/resume flow
2019-10-10 23:01 ` Jakub Kicinski
@ 2019-10-11 8:21 ` biao huang
0 siblings, 0 replies; 3+ messages in thread
From: biao huang @ 2019-10-11 8:21 UTC (permalink / raw)
To: Jakub Kicinski
Cc: davem, Jose Abreu, andrew, Giuseppe Cavallaro, Alexandre Torgue,
Maxime Coquelin, Matthias Brugger, netdev, linux-stm32,
linux-arm-kernel, linux-kernel, linux-mediatek, yt.shen,
jianguo.zhang, boon.leong.ong, yong.wu
Appreciate your comments!
On Thu, 2019-10-10 at 16:01 -0700, Jakub Kicinski wrote:
> On Wed, 9 Oct 2019 16:56:49 +0800, Biao Huang wrote:
> > disable ptp_ref_clk in suspend flow, and enable it in resume flow.
> >
> > Signed-off-by: Biao Huang <biao.huang@mediatek.com>
> > ---
> > drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > index c7c9e5f162e6..b592aeecc3dd 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > @@ -4469,6 +4469,8 @@ int stmmac_suspend(struct device *dev)
> > stmmac_mac_set(priv, priv->ioaddr, false);
> > pinctrl_pm_select_sleep_state(priv->device);
> > /* Disable clock in case of PWM is off */
> > + if (priv->plat->clk_ptp_ref)
> > + clk_disable_unprepare(priv->plat->clk_ptp_ref);
>
> I don't know much embedded, but it seems like this should perhaps just
> be clk_disable() without the unprepare? stmmac_hw_teardown() is called
> when driver is removed so it needs to unprepare as well.
>
> Please feel free to explain to me why this needs to be
> clk_disable_unprepare(), as I said - not an expert.
>
As our clock owner's advice, there are prepare/unprepare clk_ops for
pll, but no enable/disable clk_ops for it, and pll will be off only when
the prepare reference count decrease to 0.
so for the sake of power saving, we'd better call clk_disable_unprepare
to turn the parent pll off.
> Also - if this is a bug fix and you'd like to have it backported to
> older releases you need to add a Fixes tag.
>
Thanks for the reminder, I'll add the fixes tag in the next version.
> Thanks!
>
> > clk_disable(priv->plat->pclk);
> > clk_disable(priv->plat->stmmac_clk);
maybe it should be clk_disable_unprepare(priv->plat->pclk);
clk_disable_unprepare(priv->plat->stmmac_clk);
> > }
> > @@ -4535,6 +4537,8 @@ int stmmac_resume(struct device *dev)
> > /* enable the clk previously disabled */
> > clk_enable(priv->plat->stmmac_clk);
> > clk_enable(priv->plat->pclk);
> > + if (priv->plat->clk_ptp_ref)
> > + clk_prepare_enable(priv->plat->clk_ptp_ref);
> > /* reset the phy so that it's ready */
> > if (priv->mii)
> > stmmac_mdio_reset(priv->mii);
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-10-11 8:21 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2019-10-09 8:56 [PATCH] net: stmmac: disable/enable ptp_ref_clk in suspend/resume flow Biao Huang
2019-10-10 23:01 ` Jakub Kicinski
2019-10-11 8:21 ` biao huang
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