Re: [PATCH 3/6] thermal: exynos: Provide initial setting for TMU's test MUX address at Exynos4412

Lukasz Majewski
2013-10-04T10:20:31Z

Hi Eduardo,

> On 24-09-2013 04:08, Lukasz Majewski wrote:
> > The commit d0a0ce3e77c795258d47f9163e92d5031d0c5221 ("thermal:
> > exynos: Add missing definations and code cleanup") has removed
> > setting of test MUX address value at TMU configuration setting.
> >
> > This field is not present on Exynos4210 and Exynos5 SoCs. However
> > on Exynos4412 SoC it is required to set this field after reset
> > because without it TMU shows maximal available temperature, which
> > causes immediate platform shutdown.
> >
> > Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
> > Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
> > Reviewed-by: Tomasz Figa <t.figa@samsung.com>
> > ---
> > drivers/thermal/samsung/exynos_tmu.c | 3 +++
> > drivers/thermal/samsung/exynos_tmu_data.h | 4 ++++
> > 2 files changed, 7 insertions(+)
> >
> > diff --git a/drivers/thermal/samsung/exynos_tmu.c
> > b/drivers/thermal/samsung/exynos_tmu.c index a858cc4..21b89e4 100644
> > --- a/drivers/thermal/samsung/exynos_tmu.c
> > +++ b/drivers/thermal/samsung/exynos_tmu.c
> > @@ -317,6 +317,9 @@ static void exynos_tmu_control(struct
> > platform_device *pdev, bool on)
> > con = readl(data->base + reg->tmu_ctrl);
> >
> > + if (pdata->type == SOC_ARCH_EXYNOS4412)
> > + con |= (EXYNOS4412_MUX_ADDR_VALUE <<
> > EXYNOS4412_MUX_ADDR_SHIFT);
>
> Amit has introduced a way to describe features instead of checking
> features per type. It would be interesting to have a reasoning why not
> to use it.

Problem with Exynos4412 and Exynos4212 is that _only_ those SoCs export
this MUX_ADDR field at TMU_CONTROL register. Also I _must_ setup it
correctly after reset (reset value causes board emergency shutdown).

The Exynos5250 defines it as a "reserved".

> Think what if new Exynos TMU versions come, are you guys
> going to steadily increase the above check for type?

As the alternative I can define the TMU_SUPPORT_MUX_ADDR at .features
field for EXYNOS4412_TMU_DATA.

Then I can test for this feature at exynos_tmu_control function.
Proper shift and mask can be defined at struct exynos_tmu_registers.

Eduardo, Amit, will we manage to review/pull those patches with new
approach before -rcX ends?

>
> > +
> > if (pdata->reference_voltage) {
> > con &= ~(reg->buf_vref_sel_mask <<
> > reg->buf_vref_sel_shift); con |= pdata->reference_voltage <<
> > reg->buf_vref_sel_shift; diff --git
> > a/drivers/thermal/samsung/exynos_tmu_data.h
> > b/drivers/thermal/samsung/exynos_tmu_data.h index b130b1e..a1ea19d
> > 100644 --- a/drivers/thermal/samsung/exynos_tmu_data.h +++
> > b/drivers/thermal/samsung/exynos_tmu_data.h @@ -95,6 +95,10 @@
> >
> > #define EXYNOS_MAX_TRIGGER_PER_REG 4
> >
> > +/* Exynos4412 specific */
> > +#define EXYNOS4412_MUX_ADDR_VALUE 6
> > +#define EXYNOS4412_MUX_ADDR_SHIFT 20
> > +
> > /*exynos5440 specific registers*/
> > #define EXYNOS5440_TMU_S0_7_TRIM 0x000
> > #define EXYNOS5440_TMU_S0_7_CTRL 0x020
> >
>
>

--
Best regards,

Lukasz Majewski

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