linux-kernel - Re: [PATCH] firmware: qcom_scm: modify qcom_scm_set_download

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Date:   Thu, 2 Feb 2023 16:08:00 +0530
From:   Mukesh Ojha <quic_mojha@...cinc.com>
To:     Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
CC:     <agross@...nel.org>, <andersson@...nel.org>,
        <konrad.dybcio@...aro.org>, <linux-arm-msm@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] firmware: qcom_scm: modify qcom_scm_set_download_mode()



On 2/2/2023 3:42 PM, Dmitry Baryshkov wrote:
> On Tue, 24 Jan 2023 at 14:19, Mukesh Ojha <quic_mojha@...cinc.com> wrote:
>>
>> Modify qcom_scm_set_download_mode() such that it can support
>> multiple modes. There is no functional change with this change.
> 
> Please describe usecases for such a change. Without them it's just an
> unused complication.

I already mentioned the change is to support more download modes and i 
am working on the patches to add some other download modes, for which 
this may be needed as a preparation and since this change could be 
independent. so, sent it.

-Mukesh
> 
>>
>> Signed-off-by: Mukesh Ojha <quic_mojha@...cinc.com>
>> ---
>>   drivers/firmware/qcom_scm.c | 17 ++++++++---------
>>   include/linux/qcom_scm.h    |  5 +++++
>>   2 files changed, 13 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
>> index cdbfe54..712bb03 100644
>> --- a/drivers/firmware/qcom_scm.c
>> +++ b/drivers/firmware/qcom_scm.c
>> @@ -400,22 +400,22 @@ int qcom_scm_set_remote_state(u32 state, u32 id)
>>   }
>>   EXPORT_SYMBOL(qcom_scm_set_remote_state);
>>
>> -static int __qcom_scm_set_dload_mode(struct device *dev, bool enable)
>> +static int __qcom_scm_set_dload_mode(struct device *dev, enum qcom_download_mode mode)
>>   {
>>          struct qcom_scm_desc desc = {
>>                  .svc = QCOM_SCM_SVC_BOOT,
>>                  .cmd = QCOM_SCM_BOOT_SET_DLOAD_MODE,
>>                  .arginfo = QCOM_SCM_ARGS(2),
>> -               .args[0] = QCOM_SCM_BOOT_SET_DLOAD_MODE,
>> +               .args[0] = mode,
>>                  .owner = ARM_SMCCC_OWNER_SIP,
>>          };
>>
>> -       desc.args[1] = enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0;
>> +       desc.args[1] = mode;
>>
>>          return qcom_scm_call_atomic(__scm->dev, &desc, NULL);
>>   }
>>
>> -static void qcom_scm_set_download_mode(bool enable)
>> +static void qcom_scm_set_download_mode(enum qcom_download_mode mode)
>>   {
>>          bool avail;
>>          int ret = 0;
>> @@ -424,10 +424,9 @@ static void qcom_scm_set_download_mode(bool enable)
>>                                               QCOM_SCM_SVC_BOOT,
>>                                               QCOM_SCM_BOOT_SET_DLOAD_MODE);
>>          if (avail) {
>> -               ret = __qcom_scm_set_dload_mode(__scm->dev, enable);
>> +               ret = __qcom_scm_set_dload_mode(__scm->dev, mode);
>>          } else if (__scm->dload_mode_addr) {
>> -               ret = qcom_scm_io_writel(__scm->dload_mode_addr,
>> -                               enable ? QCOM_SCM_BOOT_SET_DLOAD_MODE : 0);
>> +               ret = qcom_scm_io_writel(__scm->dload_mode_addr, mode);
>>          } else {
>>                  dev_err(__scm->dev,
>>                          "No available mechanism for setting download mode\n");
>> @@ -1410,7 +1409,7 @@ static int qcom_scm_probe(struct platform_device *pdev)
>>           * disabled below by a clean shutdown/reboot.
>>           */
>>          if (download_mode)
>> -               qcom_scm_set_download_mode(true);
>> +               qcom_scm_set_download_mode(QCOM_DOWNLOAD_FULLDUMP);
>>
>>          return 0;
>>   }
>> @@ -1419,7 +1418,7 @@ static void qcom_scm_shutdown(struct platform_device *pdev)
>>   {
>>          /* Clean shutdown, disable download mode to allow normal restart */
>>          if (download_mode)
>> -               qcom_scm_set_download_mode(false);
>> +               qcom_scm_set_download_mode(QCOM_DOWNLOAD_NODUMP);
>>   }
>>
>>   static const struct of_device_id qcom_scm_dt_match[] = {
>> diff --git a/include/linux/qcom_scm.h b/include/linux/qcom_scm.h
>> index f833564..f9bc84e 100644
>> --- a/include/linux/qcom_scm.h
>> +++ b/include/linux/qcom_scm.h
>> @@ -14,6 +14,11 @@
>>   #define QCOM_SCM_CPU_PWR_DOWN_L2_OFF   0x1
>>   #define QCOM_SCM_HDCP_MAX_REQ_CNT      5
>>
>> +enum qcom_download_mode {
>> +       QCOM_DOWNLOAD_NODUMP    = 0x00,
>> +       QCOM_DOWNLOAD_FULLDUMP  = 0x10,
>> +};
>> +
>>   struct qcom_scm_hdcp_req {
>>          u32 addr;
>>          u32 val;
>> --
>> 2.7.4
>>
> 
>