From: Dmitry Osipenko <digetx@gmail.com>
To: Thierry Reding <thierry.reding@gmail.com>,
MyungJoo Ham <myungjoo.ham@samsung.com>,
Kyungmin Park <kyungmin.park@samsung.com>,
Chanwoo Choi <cw00.choi@samsung.com>,
Jonathan Hunter <jonathanh@nvidia.com>,
Tomeu Vizoso <tomeu.vizoso@collabora.com>,
Peter Geis <pgwipeout@gmail.com>
Cc: linux-pm@vger.kernel.org, linux-tegra@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH v7 04/19] PM / devfreq: tegra30: Drop write-barrier
Date: Wed, 30 Oct 2019 01:00:04 +0300 [thread overview]
Message-ID: <20191029220019.26773-5-digetx@gmail.com> (raw)
In-Reply-To: <20191029220019.26773-1-digetx@gmail.com>
There is no need in a write-barrier now, given that interrupt masking is
handled by CPU's GIC now. Hence we know exactly that interrupt won't fire
after stopping the devfreq's governor. In other cases we don't care about
potential buffering of the writes to hardware and thus there is no need to
stall CPU.
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/devfreq/tegra30-devfreq.c | 14 --------------
1 file changed, 14 deletions(-)
diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c
index bfee9d43de1e..ee14bf534c0d 100644
--- a/drivers/devfreq/tegra30-devfreq.c
+++ b/drivers/devfreq/tegra30-devfreq.c
@@ -230,12 +230,6 @@ static void tegra_devfreq_update_wmark(struct tegra_devfreq *tegra,
ACTMON_DEV_LOWER_WMARK);
}
-static void actmon_write_barrier(struct tegra_devfreq *tegra)
-{
- /* ensure the update has reached the ACTMON */
- readl(tegra->regs + ACTMON_GLB_STATUS);
-}
-
static void actmon_isr_device(struct tegra_devfreq *tegra,
struct tegra_devfreq_device *dev)
{
@@ -287,8 +281,6 @@ static void actmon_isr_device(struct tegra_devfreq *tegra,
device_writel(dev, dev_ctrl, ACTMON_DEV_CTRL);
device_writel(dev, ACTMON_INTR_STATUS_CLEAR, ACTMON_DEV_INTR_STATUS);
-
- actmon_write_barrier(tegra);
}
static unsigned long actmon_cpu_to_emc_rate(struct tegra_devfreq *tegra,
@@ -376,8 +368,6 @@ static int tegra_actmon_rate_notify_cb(struct notifier_block *nb,
tegra_devfreq_update_wmark(tegra, dev);
}
- actmon_write_barrier(tegra);
-
return NOTIFY_OK;
}
@@ -423,8 +413,6 @@ static void tegra_actmon_start(struct tegra_devfreq *tegra)
for (i = 0; i < ARRAY_SIZE(tegra->devices); i++)
tegra_actmon_configure_device(tegra, &tegra->devices[i]);
- actmon_write_barrier(tegra);
-
enable_irq(tegra->irq);
}
@@ -439,8 +427,6 @@ static void tegra_actmon_stop(struct tegra_devfreq *tegra)
device_writel(&tegra->devices[i], ACTMON_INTR_STATUS_CLEAR,
ACTMON_DEV_INTR_STATUS);
}
-
- actmon_write_barrier(tegra);
}
static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
--
2.23.0
next prev parent reply other threads:[~2019-10-29 22:07 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-29 22:00 [PATCH v7 00/19] More improvements for Tegra30 devfreq driver Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 01/19] PM / devfreq: tegra30: Change irq type to unsigned int Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 02/19] PM / devfreq: tegra30: Keep interrupt disabled while governor is stopped Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 03/19] PM / devfreq: tegra30: Handle possible round-rate error Dmitry Osipenko
2019-10-29 22:00 ` Dmitry Osipenko [this message]
2019-10-29 22:00 ` [PATCH v7 05/19] PM / devfreq: tegra30: Fix integer overflow on CPU's freq max out Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 06/19] PM / devfreq: tegra30: Use kHz units uniformly in the code Dmitry Osipenko
2019-10-31 4:44 ` Chanwoo Choi
2019-10-31 23:08 ` Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 07/19] PM / devfreq: tegra30: Use CPUFreq notifier Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 08/19] PM / devfreq: tegra30: Move clk-notifier's registration to governor's start Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 09/19] PM / devfreq: tegra30: Reset boosting on startup Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 10/19] PM / devfreq: tegra30: Don't enable consecutive-down interrupt " Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 11/19] PM / devfreq: tegra30: Constify structs Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 12/19] PM / devfreq: tegra30: Include appropriate header Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 13/19] PM / devfreq: tegra30: Increase sampling period to 16ms Dmitry Osipenko
2019-11-01 21:53 ` Michał Mirosław
2019-10-29 22:00 ` [PATCH v7 14/19] PM / devfreq: tegra30: Don't enable already enabled consecutive interrupts Dmitry Osipenko
2019-11-01 7:00 ` Chanwoo Choi
2019-10-29 22:00 ` [PATCH v7 15/19] PM / devfreq: tegra30: Disable consecutive interrupts when appropriate Dmitry Osipenko
2019-11-01 7:01 ` Chanwoo Choi
2019-10-29 22:00 ` [PATCH v7 16/19] PM / devfreq: Add new interrupt_driven flag for governors Dmitry Osipenko
2019-11-01 7:32 ` Chanwoo Choi
2019-11-01 13:56 ` Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 17/19] PM / devfreq: tegra30: Support variable polling interval Dmitry Osipenko
2019-11-01 7:41 ` Chanwoo Choi
2019-11-01 13:55 ` Dmitry Osipenko
2019-11-01 21:58 ` Michał Mirosław
2019-11-01 22:23 ` Dmitry Osipenko
2019-11-03 15:25 ` Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 18/19] PM / devfreq: tegra30: Tune up MCCPU boost-down coefficient Dmitry Osipenko
2019-11-01 7:45 ` Chanwoo Choi
2019-11-01 14:14 ` Dmitry Osipenko
2019-10-29 22:00 ` [PATCH v7 19/19] PM / devfreq: tegra20/30: Add Dmitry as a maintainer Dmitry Osipenko
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