From 2111cb9379c94fc22fa70b469325e895c497aa24 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Thu, 2 May 2019 02:38:00 +0300 Subject: [PATCH] PM / devfreq: tegra: Fix kHz to Hz conversion BugLink: https://bugs.launchpad.net/bugs/1848039 commit 62bacb06b9f08965c4ef10e17875450490c948c0 upstream. The kHz to Hz is incorrectly converted in a few places in the code, this results in a wrong frequency being calculated because devfreq core uses OPP frequencies that are given in Hz to clamp the rate, while tegra-devfreq gives to the core value in kHz and then it also expects to receive value in kHz from the core. In a result memory freq is always set to a value which is close to ULONG_MAX because of the bug. Hence the EMC frequency is always capped to the maximum and the driver doesn't do anything useful. This patch was tested on Tegra30 and Tegra124 SoC's, EMC frequency scaling works properly now. Cc: # 4.14+ Tested-by: Steev Klimaszewski Reviewed-by: Chanwoo Choi Signed-off-by: Dmitry Osipenko Acked-by: Thierry Reding Signed-off-by: MyungJoo Ham Signed-off-by: Greg Kroah-Hartman Signed-off-by: Paolo Pisati Signed-off-by: Kleber Sacilotto de Souza --- drivers/devfreq/tegra-devfreq.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c index 35c38aad8b4f..cd15c96dd27f 100644 --- a/drivers/devfreq/tegra-devfreq.c +++ b/drivers/devfreq/tegra-devfreq.c @@ -474,11 +474,11 @@ static int tegra_devfreq_target(struct device *dev, unsigned long *freq, { struct tegra_devfreq *tegra = dev_get_drvdata(dev); struct dev_pm_opp *opp; - unsigned long rate = *freq * KHZ; + unsigned long rate; - opp = devfreq_recommended_opp(dev, &rate, flags); + opp = devfreq_recommended_opp(dev, freq, flags); if (IS_ERR(opp)) { - dev_err(dev, "Failed to find opp for %lu KHz\n", *freq); + dev_err(dev, "Failed to find opp for %lu Hz\n", *freq); return PTR_ERR(opp); } rate = dev_pm_opp_get_freq(opp); @@ -487,8 +487,6 @@ static int tegra_devfreq_target(struct device *dev, unsigned long *freq, clk_set_min_rate(tegra->emc_clock, rate); clk_set_rate(tegra->emc_clock, 0); - *freq = rate; - return 0; } @@ -498,7 +496,7 @@ static int tegra_devfreq_get_dev_status(struct device *dev, struct tegra_devfreq *tegra = dev_get_drvdata(dev); struct tegra_devfreq_device *actmon_dev; - stat->current_frequency = tegra->cur_freq; + stat->current_frequency = tegra->cur_freq * KHZ; /* To be used by the tegra governor */ stat->private_data = tegra; @@ -553,7 +551,7 @@ static int tegra_governor_get_target(struct devfreq *devfreq, target_freq = max(target_freq, dev->target_freq); } - *freq = target_freq; + *freq = target_freq * KHZ; return 0; } -- 2.39.5