Re: [PATCH v3 1/4] firmware: qcom: scm: Add support for tsens reinit workaround

[Bjorn Andersson <andersson@kernel.org>]

On Thu, Aug 04, 2022 at 11:16:35AM +0530, Bhupesh Sharma wrote:
> Some versions of Qualcomm tsens controller might enter a
> 'bad state' while running stability tests causing sensor
> temperatures/interrupts status to be in an 'invalid' state.
> 
> It is recommended to re-initialize the tsens controller
> via trustzone (secure registers) using scm call(s) when that
> happens.
> 
> Add support for the same in the qcom_scm driver.
> 
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Amit Kucheria <amitk@kernel.org>
> Cc: Thara Gopinath <thara.gopinath@gmail.com>
> Cc: linux-pm@vger.kernel.org
> Cc: linux-arm-msm@vger.kernel.org
> Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
> ---
>  drivers/firmware/qcom_scm.c | 15 +++++++++++++++
>  drivers/firmware/qcom_scm.h |  4 ++++
>  include/linux/qcom_scm.h    |  2 ++
>  3 files changed, 21 insertions(+)
> 
> diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
> index cdbfe54c8146..93adcc046a62 100644
> --- a/drivers/firmware/qcom_scm.c
> +++ b/drivers/firmware/qcom_scm.c
> @@ -858,6 +858,21 @@ int qcom_scm_mem_protect_video_var(u32 cp_start, u32 cp_size,
>  }
>  EXPORT_SYMBOL(qcom_scm_mem_protect_video_var);
>  
> +int qcom_scm_tsens_reinit(void)
> +{
> +	int ret;
> +	const struct qcom_scm_desc desc = {
> +		.svc = QCOM_SCM_SVC_TSENS,
> +		.cmd = QCOM_SCM_TSENS_INIT_ID,
> +	};
> +	struct qcom_scm_res res;
> +
> +	ret = qcom_scm_call(__scm->dev, &desc, &res);
> +
> +	return ret ? : res.result[0];
> +}
> +EXPORT_SYMBOL(qcom_scm_tsens_reinit);
> +
>  static int __qcom_scm_assign_mem(struct device *dev, phys_addr_t mem_region,
>  				 size_t mem_sz, phys_addr_t src, size_t src_sz,
>  				 phys_addr_t dest, size_t dest_sz)
> diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h
> index 0d51eef2472f..495fa00230c7 100644
> --- a/drivers/firmware/qcom_scm.h
> +++ b/drivers/firmware/qcom_scm.h
> @@ -94,6 +94,10 @@ extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
>  #define QCOM_SCM_PIL_PAS_IS_SUPPORTED	0x07
>  #define QCOM_SCM_PIL_PAS_MSS_RESET	0x0a
>  
> +/* TSENS Services and Function IDs */
> +#define QCOM_SCM_SVC_TSENS		0x1E

It would be nice if this 'E' was lowercase.

Reviewed-by: Bjorn Andersson <andersson@kernel.org>

Thanks,
Bjorn

> +#define QCOM_SCM_TSENS_INIT_ID		0x5
> +
>  #define QCOM_SCM_SVC_IO			0x05
>  #define QCOM_SCM_IO_READ		0x01
>  #define QCOM_SCM_IO_WRITE		0x02
> diff --git a/include/linux/qcom_scm.h b/include/linux/qcom_scm.h
> index f8335644a01a..5c37e1658cef 100644
> --- a/include/linux/qcom_scm.h
> +++ b/include/linux/qcom_scm.h
> @@ -124,4 +124,6 @@ extern int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
>  extern int qcom_scm_lmh_profile_change(u32 profile_id);
>  extern bool qcom_scm_lmh_dcvsh_available(void);
>  
> +extern int qcom_scm_tsens_reinit(void);
> +
>  #endif
> -- 
> 2.35.3
>