Re: [PATCH v3 04/11] thermal: armada: Rationalize register accesses

Miquel RAYNAL
2017-12-18T13:48:28Z

On Fri, 15 Dec 2017 10:56:22 +0200
Baruch Siach <baruch-NswTu9S1W3P6gbPvEgmw2w@public.gmane.org> wrote:

> Hi Miquèl,
>
> On Thu, Dec 14, 2017 at 11:30:04AM +0100, Miquel Raynal wrote:
> > Bindings were incomplete for a long time by only exposing one of
> > the two available control registers. To ease the migration to the
> > full bindings (already in use for the Armada 375 SoC), rename the
> > pointers for clarification. This way, it will only be needed to add
> > another pointer to access the other control register when the time
> > comes.
> >
> > This avoids dangerous situations where the offset 0 of the control
> > area can be either one register or the other depending on the
> > bindings used. After this change, device trees of other SoCs could
> > be migrated to the "full" bindings if they may benefit from
> > features from the unaccessible register, without any change in the
> > driver.
> >
> > Signed-off-by: Miquel Raynal <miquel.raynal-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
> > ---
> > drivers/thermal/armada_thermal.c | 86
> > +++++++++++++++++++++++++--------------- 1 file changed, 55
> > insertions(+), 31 deletions(-)
> >
> > diff --git a/drivers/thermal/armada_thermal.c
> > b/drivers/thermal/armada_thermal.c index 26698f2d3ca7..e5b184cee79b
> > 100644 --- a/drivers/thermal/armada_thermal.c
> > +++ b/drivers/thermal/armada_thermal.c
> > @@ -39,12 +39,21 @@
> > #define A375_HW_RESETn BIT(8)
> > #define A380_HW_RESET BIT(8)
> >
> > +/* Legacy bindings */
> > +#define LEGACY_CONTROL_MEM_LEN 0x4
> > +
> > +/* Current bindings with the 2 control registers under the same
> > memory area */ +#define LEGACY_CONTROL1_OFFSET 0x0
> > +#define CONTROL0_OFFSET 0x0
> > +#define CONTROL1_OFFSET 0x4
> > +
> > struct armada_thermal_data;
> >
> > /* Marvell EBU Thermal Sensor Dev Structure */
> > struct armada_thermal_priv {
> > - void __iomem *sensor;
> > - void __iomem *control;
> > + void __iomem *status;
> > + void __iomem *control0;
> > + void __iomem *control1;
>
> The 'status' -> 'sensor' rename is not mentioned in the commit log.
> I'd say it is a matter for a separate patch.

Sure, I'll split.

>
> Otherwise, good cleanup.

Thanks!

Miquèl

>
> baruch
>
> > struct armada_thermal_data *data;
> > };
> >
> > @@ -71,45 +80,45 @@ struct armada_thermal_data {
> > static void armadaxp_init_sensor(struct platform_device *pdev,
> > struct armada_thermal_priv *priv)
> > {
> > - unsigned long reg;
> > + u32 reg;
> >
> > - reg = readl_relaxed(priv->control);
> > + reg = readl_relaxed(priv->control1);
> > reg |= PMU_TDC0_OTF_CAL_MASK;
> > - writel(reg, priv->control);
> > + writel(reg, priv->control1);
> >
> > /* Reference calibration value */
> > reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
> > reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
> > - writel(reg, priv->control);
> > + writel(reg, priv->control1);
> >
> > /* Reset the sensor */
> > - reg = readl_relaxed(priv->control);
> > - writel((reg | PMU_TDC0_SW_RST_MASK), priv->control);
> > + reg = readl_relaxed(priv->control1);
> > + writel((reg | PMU_TDC0_SW_RST_MASK), priv->control1);
> >
> > - writel(reg, priv->control);
> > + writel(reg, priv->control1);
> >
> > /* Enable the sensor */
> > - reg = readl_relaxed(priv->sensor);
> > + reg = readl_relaxed(priv->status);
> > reg &= ~PMU_TM_DISABLE_MASK;
> > - writel(reg, priv->sensor);
> > + writel(reg, priv->status);
> > }
> >
> > static void armada370_init_sensor(struct platform_device *pdev,
> > struct armada_thermal_priv *priv)
> > {
> > - unsigned long reg;
> > + u32 reg;
> >
> > - reg = readl_relaxed(priv->control);
> > + reg = readl_relaxed(priv->control1);
> > reg |= PMU_TDC0_OTF_CAL_MASK;
> > - writel(reg, priv->control);
> > + writel(reg, priv->control1);
> >
> > /* Reference calibration value */
> > reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
> > reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
> > - writel(reg, priv->control);
> > + writel(reg, priv->control1);
> >
> > reg &= ~PMU_TDC0_START_CAL_MASK;
> > - writel(reg, priv->control);
> > + writel(reg, priv->control1);
> >
> > msleep(10);
> > }
> > @@ -117,37 +126,37 @@ static void armada370_init_sensor(struct
> > platform_device *pdev, static void armada375_init_sensor(struct
> > platform_device *pdev, struct armada_thermal_priv *priv)
> > {
> > - unsigned long reg;
> > + u32 reg;
> >
> > - reg = readl(priv->control + 4);
> > + reg = readl(priv->control1);
> > reg &= ~(A375_UNIT_CONTROL_MASK <<
> > A375_UNIT_CONTROL_SHIFT); reg &= ~A375_READOUT_INVERT;
> > reg &= ~A375_HW_RESETn;
> >
> > - writel(reg, priv->control + 4);
> > + writel(reg, priv->control1);
> > msleep(20);
> >
> > reg |= A375_HW_RESETn;
> > - writel(reg, priv->control + 4);
> > + writel(reg, priv->control1);
> > msleep(50);
> > }
> >
> > static void armada380_init_sensor(struct platform_device *pdev,
> > struct armada_thermal_priv *priv)
> > {
> > - unsigned long reg = readl_relaxed(priv->control);
> > + u32 reg = readl_relaxed(priv->control1);
> >
> > /* Reset hardware once */
> > if (!(reg & A380_HW_RESET)) {
> > reg |= A380_HW_RESET;
> > - writel(reg, priv->control);
> > + writel(reg, priv->control1);
> > msleep(10);
> > }
> > }
> >
> > static bool armada_is_valid(struct armada_thermal_priv *priv)
> > {
> > - unsigned long reg = readl_relaxed(priv->sensor);
> > + u32 reg = readl_relaxed(priv->status);
> >
> > return reg & priv->data->is_valid_bit;
> > }
> > @@ -156,7 +165,7 @@ static int armada_get_temp(struct
> > thermal_zone_device *thermal, int *temp)
> > {
> > struct armada_thermal_priv *priv = thermal->devdata;
> > - unsigned long reg;
> > + u32 reg;
> > unsigned long m, b, div;
> >
> > /* Valid check */
> > @@ -166,7 +175,7 @@ static int armada_get_temp(struct
> > thermal_zone_device *thermal, return -EIO;
> > }
> >
> > - reg = readl_relaxed(priv->sensor);
> > + reg = readl_relaxed(priv->status);
> > reg = (reg >> priv->data->temp_shift) &
> > priv->data->temp_mask;
> > /* Get formula coeficients */
> > @@ -253,6 +262,7 @@ MODULE_DEVICE_TABLE(of,
> > armada_thermal_id_table);
> > static int armada_thermal_probe(struct platform_device *pdev)
> > {
> > + void __iomem *control = NULL;
> > struct thermal_zone_device *thermal;
> > const struct of_device_id *match;
> > struct armada_thermal_priv *priv;
> > @@ -267,14 +277,28 @@ static int armada_thermal_probe(struct
> > platform_device *pdev) return -ENOMEM;
> >
> > res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > - priv->sensor = devm_ioremap_resource(&pdev->dev, res);
> > - if (IS_ERR(priv->sensor))
> > - return PTR_ERR(priv->sensor);
> > + priv->status = devm_ioremap_resource(&pdev->dev, res);
> > + if (IS_ERR(priv->status))
> > + return PTR_ERR(priv->status);
> >
> > res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > - priv->control = devm_ioremap_resource(&pdev->dev, res);
> > - if (IS_ERR(priv->control))
> > - return PTR_ERR(priv->control);
> > + control = devm_ioremap_resource(&pdev->dev, res);
> > + if (IS_ERR(control))
> > + return PTR_ERR(control);
> > +
> > + /*
> > + * Legacy DT bindings only described "control1" register
> > (also referred
> > + * as "control MSB" on old documentation). New bindings
> > cover
> > + * "control0/control LSB" and "control1/control MSB"
> > registers within
> > + * the same resource, which is then of size 8 instead of 4.
> > + */
> > + if ((res->end - res->start) == LEGACY_CONTROL_MEM_LEN) {
> > + /* ->control0 unavailable in this configuration */
> > + priv->control1 = control + LEGACY_CONTROL1_OFFSET;
> > + } else {
> > + priv->control0 = control + CONTROL0_OFFSET;
> > + priv->control1 = control + CONTROL1_OFFSET;
> > + }
> >
> > priv->data = (struct armada_thermal_data *)match->data;
> > priv->data->init_sensor(pdev, priv);
>

--
Miquel Raynal, Free Electrons
Embedded Linux and Kernel engineering