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| author |   Miquel Raynal <miquel.raynal@bootlin.com> | 2018-07-16 16:41:49 +0200 |
|---|---|---|
| committer |   Eduardo Valentin <edubezval@gmail.com> | 2018-07-27 14:43:06 -0700 |
| commit | a9fae794e4c581bbe460106609ce88dec8b00973 (patch) | |
| tree | 274d2c95a9bd9a24dabbd00ea5530c020f893380 /drivers/thermal/armada_thermal.c | |
| parent | thermal: armada: dissociate a380 and cp110 ->init() hooks (diff) | |
| download | linux-dev-a9fae794e4c581bbe460106609ce88dec8b00973.tar.xz linux-dev-a9fae794e4c581bbe460106609ce88dec8b00973.zip | |
thermal: armada: average over samples to avoid glitches
Configure the sample frequency and number of averaged samples.
This is needed for two reasons:
1/ To be bootloader independent.
2/ To prepare the introduction of multi-sensors support by preventing
inconsistencies when reading temperatures that could be a mean of
samples took from different sensors.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Diffstat (limited to 'drivers/thermal/armada_thermal.c')
| -rw-r--r-- | drivers/thermal/armada_thermal.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/thermal/armada_thermal.c b/drivers/thermal/armada_thermal.c index 31ff57a654ba..05214ebf1093 100644 --- a/drivers/thermal/armada_thermal.c +++ b/drivers/thermal/armada_thermal.c @@ -54,7 +54,12 @@ #define CONTROL0_TSEN_START BIT(0) #define CONTROL0_TSEN_RESET BIT(1) #define CONTROL0_TSEN_ENABLE BIT(2) +#define CONTROL0_TSEN_AVG_BYPASS BIT(6) +#define CONTROL0_TSEN_OSR_SHIFT 24 +#define CONTROL0_TSEN_OSR_MAX 0x3 +#define CONTROL1_TSEN_AVG_SHIFT 0 +#define CONTROL1_TSEN_AVG_MASK 0x7 #define CONTROL1_EXT_TSEN_SW_RESET BIT(7) #define CONTROL1_EXT_TSEN_HW_RESETn BIT(8) @@ -194,6 +199,13 @@ static void armada_ap806_init(struct platform_device *pdev, reg = readl_relaxed(priv->control0); reg &= ~CONTROL0_TSEN_RESET; reg |= CONTROL0_TSEN_START | CONTROL0_TSEN_ENABLE; + + /* Sample every ~2ms */ + reg |= CONTROL0_TSEN_OSR_MAX << CONTROL0_TSEN_OSR_SHIFT; + + /* Enable average (2 samples by default) */ + reg &= ~CONTROL0_TSEN_AVG_BYPASS; + writel(reg, priv->control0); /* Wait the sensors to be valid or the core will warn the user */ @@ -203,7 +215,20 @@ static void armada_ap806_init(struct platform_device *pdev, static void armada_cp110_init(struct platform_device *pdev, struct armada_thermal_priv *priv) { + u32 reg; + armada380_init(pdev, priv); + + /* Sample every ~2ms */ + reg = readl_relaxed(priv->control0); + reg |= CONTROL0_TSEN_OSR_MAX << CONTROL0_TSEN_OSR_SHIFT; + writel(reg, priv->control0); + + /* Average the output value over 2^1 = 2 samples */ + reg = readl_relaxed(priv->control1); + reg &= ~CONTROL1_TSEN_AVG_MASK << CONTROL1_TSEN_AVG_SHIFT; + reg |= 1 << CONTROL1_TSEN_AVG_SHIFT; + writel(reg, priv->control1); } static bool armada_is_valid(struct armada_thermal_priv *priv) |