On Wed, Feb 08, 2023 at 11:13:33AM +0800, zhuyinbo wrote:
[ ... ]
> > > +struct loongson2_thermal_data {
> > > + struct thermal_zone_device *tzd;
> > 'tzd' won't be needed after taking into account the comments
>
> The 'tzd' element is needed, because the thermal_zone_device_update need
> pass a data->tzd element.
>
> static irqreturn_t loongson2_thermal_irq_thread(int irq, void *dev)
> {
> struct loongson2_thermal_data *data = dev;
>
> thermal_zone_device_update(data->tzd,
> THERMAL_EVENT_UNSPECIFIED);
> enable_irq(data->irq);
>
> return IRQ_HANDLED;
> }
After taking into account all the comments, enabled_irq() won't be
called, so 'data' won't be needed. 'tzd' will be passed to
devm_request_threaded_irq() instead of 'data'.
As loongson2_thermal_irq_thread() is the only place where 'tzd' is
needed and 'tzd' being local to the call site of
thermal_zone_device_register() and devm_request_threaded_irq(), there
is no need to store the pointer in the 'data' structure.
> >
> > > + int irq;
> > 'irq' won't be needed after taking into account the comments
> I will drop it.
> > > + int id;
> > > + void __iomem *regs;
> > > + struct platform_device *pdev;
> > 'pdev' is not needed
> I will drop it.
> >
> > > + u16 ctrl_low_val;
> > > + u16 ctrl_hi_val;
> > Those fields won't be needed after taking into account the comments
> I will drop it.
> > > +};
> > > +
> > > +static int loongson2_thermal_set(struct loongson2_thermal_data *data,
> > > + int low, int high, bool enable)
> > > +{
> > > + u64 reg_ctrl = 0;
> > > + int reg_off = data->id * 2;
> > > +
> > > + if (low > high)
> > > + return -EINVAL;
> > > +
> > > + low = max(low, -100);
> > > + high = min(high, 155);
Documentation says -40, 125
> > > + low += 100;
> > > + high += 100;
> > Why are those values added to the low and high ? Did you mean low += 0x100 ?
> >
> > Mind to describe a bit the register layout?
>
> node(cpu) temp = Thens0_out -100,
>
> low and high is record node temp, so low and high need add '100' as
> Thens0_out.
If I refer to the documentation it is a raw value converted from
centigrade. The function has degree.
So it should be:
temp_deci = temp_milli / 10
raw = temp_to_raw(temp_deci);
-> temp_to_raw to be determined from temp = (raw * 731) / 0x4000 - 273
[ ... ]
> > > +static int loongson2_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
> > > +{
> > > + u32 reg_val;
> > > + struct loongson2_thermal_data *data = tz->devdata;
> > > +
> > > + reg_val = readl(data->regs + LOONGSON2_TSENSOR_OUT);
> > > + *temp = ((reg_val & 0xff) - 100) * 1000;
> > Why '-100' ?
> >
> > Is the unit returned 'degrees' ?
>
> node(cpu) temp = Thens0_out -100,
>
> Here we need to get a node temp.
If I refer to the Loongson-3A5000 manual and assuming it is the right
one, the documentation says:
Temperature = Thens0_out * 731 / 0x4000 - 273
The unit is centigrade.
[ ... ]
> > > + writeb(0xff, data->regs + LOONGSON2_TSENSOR_STATUS);
> > > +
> > > + loongson2_thermal_set(data, 0, 0, false);
> > It would be nicer to use a reset line if it is available
> sorry, I don't get your meaning. Please describe more details about 'reset
> line'.
After a reset, the thermal controller should be in default state and the interrupt
flag cleared.
One example:
[1] https://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux.git/tree/arch/arm64/boot/dts/nvidia/tegra210.dtsi#n1560
[2] https://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux.git/tree/drivers/thermal/tegra/soctherm.c#n2169
Then search in the driver for:
reset_control_assert(reset);
reset_control_deassert(reset);
[ ... ]
Thanks
-- Daniel
--
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