Bandgap Temperature read Dtemp can be corrupted
DESCRIPTION
Read accesses to registers listed below can be corrupted due to
incorrect resynchronization between clock domains.
Read access to registers below can be corrupted :
• CTRL_CORE_DTEMP_MPU/GPU/CORE/DSPEVE/IVA_n (n = 0 to 4)
• CTRL_CORE_TEMP_SENSOR_MPU/GPU/CORE/DSPEVE/IVA_n
WORKAROUND
Multiple reads to CTRL_CORE_TEMP_SENSOR_MPU/GPU/CORE/DSPEVE/IVA[9:0]:
BGAP_DTEMPMPU/GPU/CORE/DSPEVE/IVA is needed to discard false value and
read right value:
1. Perform two successive reads to BGAP_DTEMP bit field.
(a) If read1 returns Val1 and read2 returns Val1, then
right value is Val1.
(b) If read1 returns Val1, read 2 returns Val2, a third
read is needed.
2. Perform third read
(a) If read3 returns Val2 then right value is Val2.
(b) If read3 returns Val3, then right value is Val3.
The above in gist means if val1 and val2 are the same then we can go
ahead with that value else we need a third read which will be right
since synchronization will be complete by then.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Fix following build warning if CONFIG_PM_SLEEP is not set:
drivers/thermal/ti-soc-thermal/ti-bandgap.c:1478:12: warning: 'ti_bandgap_suspend' defined but not used [-Wunused-function]
static int ti_bandgap_suspend(struct device *dev)
^
drivers/thermal/ti-soc-thermal/ti-bandgap.c:1492:12: warning: 'ti_bandgap_resume' defined but not used [-Wunused-function]
static int ti_bandgap_resume(struct device *dev)
^
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Grygorii Strashko <Grygorii.Strashko@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Treat both negative and zero return values from clk_round_rate() as
errors. This is needed since subsequent patches will convert
clk_round_rate()'s return value to be an unsigned type, rather than a
signed type, since some clock sources can generate rates higher than
(2^31)-1 Hz.
Eventually, when calling clk_round_rate(), only a return value of zero
will be considered a error. All other values will be considered valid
rates. The comparison against values less than 0 is kept to preserve
the correct behavior in the meantime.
This patch also gets rid of a comparison between unsigned and signed
values; a side-benefit.
Signed-off-by: Paul Walmsley <pwalmsley@nvidia.com>
Cc: Eduardo Valentin <eduardo.valentin@ti.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Use SIMPLE_DEV_PM_OPS macro in order to make the code simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Workaround to compute thermal trend even when update interval
is not set. This patch will ensure to compute the thermal trend
when bandgap counter delay is not set.
Signed-off-by: Ranganath Krishnan <ranganath@ti.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
This change updates the ti-soc-thermal driver to use
standard GPIO DT bindings to read the GPIO number associated
to thermal shutdown IRQ, in case the device features it.
Previously, the code was using a specific DT bindings.
As now OMAP supports the standard way to model GPIOs,
there is no point in having a ti specific binding.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
This patch changes the driver to avoid the usage of IS_ERR_OR_NULL()
macro. This macro can lead to dangerous results, like returning
success (0) during a failure scenario (NULL pointer handling).
For this reason this patch is changing the driver after
revisiting the code. These are the cases:
i. For cases in which IS_ERR_OR_NULL() is used for checking
return values of functions that returns either PTR_ERR()
or a valid pointer, it has been translated to IS_ERR() check only.
ii. For cases that a NULL check is still needed, it has been
translated to if (!ptr || IS_ERR(ptr)).
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
In order to read the history buffer, it is required to
freeze BG FSM. This patch adds the missing piece of code
to freeze the FSM and also a contention area to avoid
other parts of the code to access the DTEMPs.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
