Hi, Daniel
> Subject: Re: [PATCH 2/3] thermal: imx8mm: Add i.MX8MP support
>
> On 08/03/2020 16:27, Anson Huang wrote:
> > i.MX8MP shares same TMU with i.MX8MM, the only difference is i.MX8MP
> > has two thermal sensors while i.MX8MM ONLY has one, add multiple
> > sensors support for i.MX8MM TMU driver.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> > ---
> > drivers/thermal/imx8mm_thermal.c | 108
> > +++++++++++++++++++++++++++++++++------
> > 1 file changed, 93 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/thermal/imx8mm_thermal.c
> > b/drivers/thermal/imx8mm_thermal.c
> > index d597ceb..8a87ed0 100644
> > --- a/drivers/thermal/imx8mm_thermal.c
> > +++ b/drivers/thermal/imx8mm_thermal.c
> > @@ -10,34 +10,75 @@
> > #include <linux/io.h>
> > #include <linux/module.h>
> > #include <linux/of.h>
> > -#include <linux/of_address.h>
> > +#include <linux/of_device.h>
> > #include <linux/platform_device.h>
> > #include <linux/thermal.h>
> >
> > #include "thermal_core.h"
> >
> > #define TER 0x0 /* TMU enable */
> > +#define TPS 0x4
> > #define TRITSR 0x20 /* TMU immediate temp */
> >
> > #define TER_EN BIT(31)
> > #define TRITSR_VAL_MASK 0xff
> >
> > -#define TEMP_LOW_LIMIT 10
> > +#define PROBE_SEL_ALL GENMASK(31, 30)
> >
> > -struct imx8mm_tmu {
> > +#define PROBE0_STATUS_OFFSET 30
> > +#define PROBE0_VAL_OFFSET 16
> > +#define SIGN_BIT BIT(7)
> > +#define TEMP_VAL_MASK GENMASK(6, 0)
> > +
> > +#define VER1_TEMP_LOW_LIMIT 10
> > +#define VER2_TEMP_LOW_LIMIT -40
> > +#define VER2_TEMP_HIGH_LIMIT 125
> > +
> > +#define TMU_VER1 0x1
> > +#define TMU_VER2 0x2
> > +
> > +struct thermal_soc_data {
> > + u32 num_sensors;
> > + u32 version;
> > +};
> > +
> > +struct tmu_sensor {
> > + struct imx8mm_tmu *priv;
> > + u32 hw_id;
> > struct thermal_zone_device *tzd;
> > +};
> > +
> > +struct imx8mm_tmu {
> > void __iomem *base;
> > struct clk *clk;
> > + const struct thermal_soc_data *socdata;
> > + struct tmu_sensor sensors[0];
> > };
> >
> > static int tmu_get_temp(void *data, int *temp) {
> > - struct imx8mm_tmu *tmu = data;
> > + struct tmu_sensor *sensor = data;
> > + struct imx8mm_tmu *tmu = sensor->priv;
> > + bool ready;
> > u32 val;
> >
> > - val = readl_relaxed(tmu->base + TRITSR) & TRITSR_VAL_MASK;
> > - if (val < TEMP_LOW_LIMIT)
> > - return -EAGAIN;
> > + if (tmu->socdata->version == TMU_VER1) {
>
> Don't do this here, implement a callback to read the temp, store it in the
> socdata and call it directly from here.
>
> So you end up with something simple like:
>
> *temp = tmu->socdata->get_temp(...);
>
Make sense, do it in V2.
> > + val = readl_relaxed(tmu->base + TRITSR) &
> TRITSR_VAL_MASK;
> > + if (val < VER1_TEMP_LOW_LIMIT)
> > + return -EAGAIN;> + } else {
> > + val = readl_relaxed(tmu->base + TRITSR);
> > + ready = val & (1 << (sensor->hw_id +
> PROBE0_STATUS_OFFSET));
>
> test_bit()?
OK.
>
> > + val = (val >> (sensor->hw_id * PROBE0_VAL_OFFSET))
> > + & TRITSR_VAL_MASK;
> > + if (val & SIGN_BIT) /* negative */
> > + val = (~(val & TEMP_VAL_MASK) + 1);
>
> Please have a look at the different bitops available to simplify this decoding.
I can ONLY find the FIELD_GET for getting the temperature value field, for the positive
and negative value check, I can't find any API for it.
>
> > + *temp = val;
> > + if (!ready || *temp < VER2_TEMP_LOW_LIMIT ||
> > + *temp > VER2_TEMP_HIGH_LIMIT)
> > + return -EAGAIN;
> > + }
> >
> > *temp = val * 1000;
> >
> > @@ -50,14 +91,21 @@ static struct thermal_zone_of_device_ops
> > tmu_tz_ops = {
> >
> > static int imx8mm_tmu_probe(struct platform_device *pdev) {
> > + const struct thermal_soc_data *data;
> > struct imx8mm_tmu *tmu;
> > u32 val;
> > int ret;
> > + int i;
> > +
> > + data = of_device_get_match_data(&pdev->dev);
> >
> > - tmu = devm_kzalloc(&pdev->dev, sizeof(struct imx8mm_tmu),
> GFP_KERNEL);
> > + tmu = devm_kzalloc(&pdev->dev, struct_size(tmu, sensors,
> > + data->num_sensors), GFP_KERNEL);
> > if (!tmu)
> > return -ENOMEM;
> >
> > + tmu->socdata = data;
> > +
> > tmu->base = devm_platform_ioremap_resource(pdev, 0);
> > if (IS_ERR(tmu->base))
> > return PTR_ERR(tmu->base);
> > @@ -77,16 +125,35 @@ static int imx8mm_tmu_probe(struct
> platform_device *pdev)
> > return ret;
> > }
> >
> > - tmu->tzd = devm_thermal_zone_of_sensor_register(&pdev->dev, 0,
> > - tmu, &tmu_tz_ops);
> > - if (IS_ERR(tmu->tzd)) {
> > - dev_err(&pdev->dev,
> > - "failed to register thermal zone sensor: %d\n", ret);
> > - return PTR_ERR(tmu->tzd);
> > + /* disable the monitor during initialization */
> > + val = readl_relaxed(tmu->base + TER);
> > + val &= ~TER_EN;
> > + writel_relaxed(val, tmu->base + TER);
>
> Could you wrap those calls inside a small helper function with a self
> described name?
OK.
>
> > +
> > + for (i = 0; i < data->num_sensors; i++) {
> > + tmu->sensors[i].priv = tmu;
> > + tmu->sensors[i].tzd =
> > + devm_thermal_zone_of_sensor_register(&pdev->dev,
> i,
> > + &tmu->sensors[i],
> > + &tmu_tz_ops);
> > + if (IS_ERR(tmu->sensors[i].tzd)) {
> > + dev_err(&pdev->dev,
> > + "failed to register thermal zone
> sensor[%d]: %d\n",
> > + i, ret);
> > + return PTR_ERR(tmu->sensors[i].tzd);
> > + }
> > + tmu->sensors[i].hw_id = i;
>
> May be you can store the offset directly, so it is not computed every time the
> temperature is read?
There are 2 place need to identify the sensor ID, the ready bit and the temperature
value field, so I think the hw_id is necessary, and it also make the logic easy to read.
>
> > }
> >
> > platform_set_drvdata(pdev, tmu);
> >
> > + /* enable all the probes for V2 TMU */
> > + if (tmu->socdata->version == TMU_VER2) {
> > + val = readl_relaxed(tmu->base + TPS);
> > + val |= PROBE_SEL_ALL;
> > + writel_relaxed(val, tmu->base + TPS);
> > + }
>
> Same comment as before about putting these in a helper
OK
Please help review V2 patch.
Thanks,
Anson
