From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gregory CLEMENT Subject: Re: [PATCH v3 09/11] thermal: armada: Wait sensors validity before exiting the init callback Date: Thu, 14 Dec 2017 12:23:11 +0100 Message-ID: <87ind9o8o0.fsf@free-electrons.com> References: <20171214103011.24713-1-miquel.raynal@free-electrons.com> <20171214103011.24713-10-miquel.raynal@free-electrons.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Return-path: Received: from mail.free-electrons.com ([62.4.15.54]:59404 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751198AbdLNLXX (ORCPT ); Thu, 14 Dec 2017 06:23:23 -0500 In-Reply-To: <20171214103011.24713-10-miquel.raynal@free-electrons.com> (Miquel Raynal's message of "Thu, 14 Dec 2017 11:30:09 +0100") Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Miquel Raynal Cc: Zhang Rui , Eduardo Valentin , Rob Herring , Mark Rutland , Jason Cooper , Andrew Lunn , Sebastian Hesselbarth , Catalin Marinas , Will Deacon , Thomas Petazzoni , devicetree@vger.kernel.org, Baruch Siach , linux-pm@vger.kernel.org, Antoine Tenart , Nadav Haklai , David Sniatkiwicz , linux-arm-kernel@lists.infradead.org Hi Miquel, On jeu., déc. 14 2017, Miquel Raynal wrote: > The thermal core will check for sensors validity right after the > initialization callback has returned. As the initialization routine make > a reset, the sensors are not ready immediately and the core spawns an > error in the dmesg. Avoid this annoying situation by polling on the > validity bit before exiting from these routines. This also avoid the use > of blind sleeps. You only modified the armada 380 and ap806 init function. Does it means that this feature is not supported on the other variant? Gregory > > Suggested-by: David Sniatkiwicz > Signed-off-by: Miquel Raynal > --- > drivers/thermal/armada_thermal.c | 23 ++++++++++++++++++++--- > 1 file changed, 20 insertions(+), 3 deletions(-) > > diff --git a/drivers/thermal/armada_thermal.c b/drivers/thermal/armada_thermal.c > index be141ca53e83..1c4122f7377c 100644 > --- a/drivers/thermal/armada_thermal.c > +++ b/drivers/thermal/armada_thermal.c > @@ -23,6 +23,7 @@ > #include > #include > #include > +#include > > /* Thermal Manager Control and Status Register */ > #define PMU_TDC0_SW_RST_MASK (0x1 << 1) > @@ -59,6 +60,9 @@ > #define CONTROL1_EXT_TSEN_SW_RESET BIT(7) > #define CONTROL1_EXT_TSEN_HW_RESETn BIT(8) > > +#define STATUS_POLL_PERIOD_US 1000 > +#define STATUS_POLL_TIMEOUT_US 100000 > + > struct armada_thermal_data; > > /* Marvell EBU Thermal Sensor Dev Structure */ > @@ -154,6 +158,16 @@ static void armada375_init_sensor(struct platform_device *pdev, > msleep(50); > } > > +static void armada_wait_sensor_validity(struct armada_thermal_priv *priv) > +{ > + u32 reg; > + > + readl_relaxed_poll_timeout(priv->status, reg, > + reg & priv->data->is_valid_bit, > + STATUS_POLL_PERIOD_US, > + STATUS_POLL_TIMEOUT_US); > +} > + > static void armada380_init_sensor(struct platform_device *pdev, > struct armada_thermal_priv *priv) > { > @@ -163,7 +177,6 @@ static void armada380_init_sensor(struct platform_device *pdev, > reg |= CONTROL1_EXT_TSEN_HW_RESETn; > reg &= ~CONTROL1_EXT_TSEN_SW_RESET; > writel(reg, priv->control1); > - msleep(10); > > /* Set Tsen Tc Trim to correct default value (errata #132698) */ > if (priv->control0) { > @@ -171,8 +184,10 @@ static void armada380_init_sensor(struct platform_device *pdev, > reg &= ~CONTROL0_TSEN_TC_TRIM_MASK; > reg |= CONTROL0_TSEN_TC_TRIM_VAL; > writel(reg, priv->control0); > - msleep(10); > } > + > + /* Wait the sensors to be valid or the core will warn the user */ > + armada_wait_sensor_validity(priv); > } > > static void armada_ap806_init_sensor(struct platform_device *pdev, > @@ -190,7 +205,9 @@ static void armada_ap806_init_sensor(struct platform_device *pdev, > reg &= ~CONTROL0_TSEN_RESET; > reg |= CONTROL0_TSEN_START | CONTROL0_TSEN_ENABLE; > writel(reg, priv->control0); > - msleep(10); > + > + /* Wait the sensors to be valid or the core will warn the user */ > + armada_wait_sensor_validity(priv); > } > > static bool armada_is_valid(struct armada_thermal_priv *priv) > -- > 2.11.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- Gregory Clement, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com