linux-kernel - Re: [PATCH v11 3/4] firmware: qcom: scm: Rework dload mode availability check

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Date: Mon, 8 Jan 2024 17:02:13 -0800
From: Elliot Berman <quic_eberman@...cinc.com>
To: Mukesh Ojha <quic_mojha@...cinc.com>, <andersson@...nel.org>,
        <konrad.dybcio@...aro.org>, <linus.walleij@...aro.org>
CC: <linux-arm-msm@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <linux-gpio@...r.kernel.org>
Subject: Re: [PATCH v11 3/4] firmware: qcom: scm: Rework dload mode
 availability check



On 1/8/2024 7:27 AM, Mukesh Ojha wrote:
> QCOM_SCM_BOOT_SET_DLOAD_MODE was only valid for very older
> target and firmware and for recent targets there is dload
> mode tcsr registers is available to set the download mode.
> 
> So, it is better to keep it as fallback check instead of
> checking its availability and failing it always.
> 
> Signed-off-by: Mukesh Ojha <quic_mojha@...cinc.com>

Reviewed-by: Elliot Berman <quic_eberman@...cinc.com>

> ---
>  drivers/firmware/qcom/qcom_scm.c | 12 +++++-------
>  1 file changed, 5 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
> index 4421f219fe9a..87bcd5c02f2b 100644
> --- a/drivers/firmware/qcom/qcom_scm.c
> +++ b/drivers/firmware/qcom/qcom_scm.c
> @@ -532,18 +532,16 @@ static int __qcom_scm_set_dload_mode(struct device *dev, bool enable)
>  static void qcom_scm_set_download_mode(bool enable)
>  {
>  	u32 val = enable ? QCOM_DLOAD_FULLDUMP : QCOM_DLOAD_NODUMP;
> -	bool avail;
>  	int ret = 0;
>  
> -	avail = __qcom_scm_is_call_available(__scm->dev,
> -					     QCOM_SCM_SVC_BOOT,
> -					     QCOM_SCM_BOOT_SET_DLOAD_MODE);
> -	if (avail) {
> -		ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
> -	} else if (__scm->dload_mode_addr) {
> +	if (__scm->dload_mode_addr) {
>  		ret = qcom_scm_io_rmw(__scm->dload_mode_addr,
>  				      QCOM_DLOAD_MASK,
>  				      FIELD_PREP(QCOM_DLOAD_MASK, val));
> +	} else if (__qcom_scm_is_call_available(__scm->dev,
> +						QCOM_SCM_SVC_BOOT,
> +						QCOM_SCM_BOOT_SET_DLOAD_MODE)) {
> +		ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
>  	} else {
>  		dev_err(__scm->dev,
>  			"No available mechanism for setting download mode\n");