Re: [PATCH v10 15/33] remoteproc: k3: Refactor rproc_reset() implementation into common driver

[Beleswar Prasad Padhi <b-padhi@ti.com>]

Hi Andrew,

On 21/04/25 20:12, Andrew Davis wrote:
> On 4/17/25 1:19 PM, Beleswar Padhi wrote:
>> The rproc_reset() implementations in TI K3 DSP and M4 remoteproc drivers
>> assert reset in the same way. Refactor the above function into the
>> ti_k3_common.c driver as k3_rproc_reset() and use it throughout DSP and
>> M4 drivers for resetting the remote processor.
>>
>> Signed-off-by: Beleswar Padhi <b-padhi@ti.com>
>> ---
>> v10: Changelog:
>> 1. Split [v9 12/26] into [v10 14/33] and [v10 15/33] patches.
>>
>> Link to v9:
>> https://lore.kernel.org/all/20250317120622.1746415-13-b-padhi@ti.com/
>>
>>   drivers/remoteproc/ti_k3_common.c         | 25 ++++++++++++++++++++
>>   drivers/remoteproc/ti_k3_common.h         |  1 +
>>   drivers/remoteproc/ti_k3_dsp_remoteproc.c | 28 ++---------------------
>>   drivers/remoteproc/ti_k3_m4_remoteproc.c  | 16 +++----------
>>   4 files changed, 31 insertions(+), 39 deletions(-)
>>
>> diff --git a/drivers/remoteproc/ti_k3_common.c b/drivers/remoteproc/ti_k3_common.c
>> index aace308b49b0e..19bb6c337af77 100644
>> --- a/drivers/remoteproc/ti_k3_common.c
>> +++ b/drivers/remoteproc/ti_k3_common.c
>> @@ -105,5 +105,30 @@ void k3_rproc_kick(struct rproc *rproc, int vqid)
>>   }
>>   EXPORT_SYMBOL_GPL(k3_rproc_kick);
>>   +/* Put the remote processor into reset */
>> +int k3_rproc_reset(struct k3_rproc *kproc)
>> +{
>> +    struct device *dev = kproc->dev;
>> +    int ret;
>> +
>> +    if (kproc->data->uses_lreset) {
>> +        ret = reset_control_assert(kproc->reset);
>> +        if (ret)
>> +            dev_err(dev, "local-reset assert failed (%pe)\n", ERR_PTR(ret));
>> +        return ret;
>> +    }
>> +
>> +    ret = kproc->ti_sci->ops.dev_ops.put_device(kproc->ti_sci,
>> +                            kproc->ti_sci_id);
>> +    if (ret) {
>> +        dev_err(dev, "module-reset assert failed (%pe)\n", ERR_PTR(ret));
>> +        if (reset_control_deassert(kproc->reset))
>> +            dev_warn(dev, "local-reset deassert back failed\n");
>> +    }
>> +
>> +    return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(k3_rproc_reset);
>> +
>>   MODULE_LICENSE("GPL");
>>   MODULE_DESCRIPTION("TI K3 common Remoteproc code");
>> diff --git a/drivers/remoteproc/ti_k3_common.h b/drivers/remoteproc/ti_k3_common.h
>> index 6ae7ac4ec5696..f3400fc774766 100644
>> --- a/drivers/remoteproc/ti_k3_common.h
>> +++ b/drivers/remoteproc/ti_k3_common.h
>> @@ -90,4 +90,5 @@ struct k3_rproc {
>>     void k3_rproc_mbox_callback(struct mbox_client *client, void *data);
>>   void k3_rproc_kick(struct rproc *rproc, int vqid);
>> +int k3_rproc_reset(struct k3_rproc *kproc);
>>   #endif /* REMOTEPROC_TI_K3_COMMON_H */
>> diff --git a/drivers/remoteproc/ti_k3_dsp_remoteproc.c b/drivers/remoteproc/ti_k3_dsp_remoteproc.c
>> index 0a8c9e61393d2..f8a5282df5b71 100644
>> --- a/drivers/remoteproc/ti_k3_dsp_remoteproc.c
>> +++ b/drivers/remoteproc/ti_k3_dsp_remoteproc.c
>> @@ -24,30 +24,6 @@
>>     #define KEYSTONE_RPROC_LOCAL_ADDRESS_MASK    (SZ_16M - 1)
>>   -/* Put the DSP processor into reset */
>> -static int k3_dsp_rproc_reset(struct k3_rproc *kproc)
>> -{
>> -    struct device *dev = kproc->dev;
>> -    int ret;
>> -
>> -    if (kproc->data->uses_lreset) {
>> -        ret = reset_control_assert(kproc->reset);
>> -        if (ret)
>> -            dev_err(dev, "local-reset assert failed (%pe)\n", ERR_PTR(ret));
>> -        return ret;
>> -    }
>> -
>> -    ret = kproc->ti_sci->ops.dev_ops.put_device(kproc->ti_sci,
>> -                            kproc->ti_sci_id);
>> -    if (ret) {
>> -        dev_err(dev, "module-reset assert failed (%pe)\n", ERR_PTR(ret));
>> -        if (reset_control_deassert(kproc->reset))
>> -            dev_warn(dev, "local-reset deassert back failed\n");
>> -    }
>> -
>> -    return ret;
>> -}
>> -
>>   /* Release the DSP processor from reset */
>>   static int k3_dsp_rproc_release(struct k3_rproc *kproc)
>>   {
>> @@ -201,7 +177,7 @@ static int k3_dsp_rproc_stop(struct rproc *rproc)
>>   {
>>       struct k3_rproc *kproc = rproc->priv;
>>   -    k3_dsp_rproc_reset(kproc);
>> +    k3_rproc_reset(kproc);
>>         return 0;
>>   }
>> @@ -565,7 +541,7 @@ static int k3_dsp_rproc_probe(struct platform_device *pdev)
>>                   return dev_err_probe(dev, ret, "failed to get reset status\n");
>>               } else if (ret == 0) {
>>                   dev_warn(dev, "local reset is deasserted for device\n");
>> -                k3_dsp_rproc_reset(kproc);
>> +                k3_rproc_reset(kproc);
>>               }
>>           }
>>       }
>> diff --git a/drivers/remoteproc/ti_k3_m4_remoteproc.c b/drivers/remoteproc/ti_k3_m4_remoteproc.c
>> index 8a6917259ce60..7d5b75be2e4f8 100644
>> --- a/drivers/remoteproc/ti_k3_m4_remoteproc.c
>> +++ b/drivers/remoteproc/ti_k3_m4_remoteproc.c
>> @@ -65,11 +65,9 @@ static int k3_m4_rproc_prepare(struct rproc *rproc)
>>        * Ensure the local reset is asserted so the core doesn't
>>        * execute bogus code when the module reset is released.
>>        */
>> -    ret = reset_control_assert(kproc->reset);
>> -    if (ret) {
>> -        dev_err(dev, "could not assert local reset\n");
>> +    ret = k3_rproc_reset(kproc);
>> +    if (ret)
>>           return ret;
>> -    }
>>         ret = reset_control_status(kproc->reset);
>>       if (ret <= 0) {
>> @@ -374,16 +372,8 @@ static int k3_m4_rproc_start(struct rproc *rproc)
>>   static int k3_m4_rproc_stop(struct rproc *rproc)
>>   {
>>       struct k3_rproc *kproc = rproc->priv;
>> -    struct device *dev = kproc->dev;
>> -    int ret;
>>   -    ret = reset_control_assert(kproc->reset);
>> -    if (ret) {
>> -        dev_err(dev, "local-reset assert failed, ret = %d\n", ret);
>> -        return ret;
>> -    }
>> -
>> -    return 0;
>> +    return k3_rproc_reset(kproc);
>
> This doesn't feel right. The new common k3_rproc_reset() function
> matches what ti_k3_dsp_remoteproc.c did for reset, you made it that
> way in the previous patch [14/33]. But it doesn't match what this
> M4 version does (yes I know logically they are the same as `uses_lreset`
> will be always true for M4). Maybe you want to do the same as you
> did for DSP to the M4 driver first, before you make this change so
> it is 100% clear the code is the same (and so bisect lands on the
> right patch should someday this be an issue).


Sure, I can make that change in next revision...

>
> Also, the common k3_rproc_reset() calls put_device() unconditionally.
> Something that wasn't done at all here in the M4 prepare() and stop()
> functions.


There is a 'return ret' in the 'if (kproc->data->uses_lreset)' condition flow in k3_rproc_reset().

put_device() should not be unconditional...

>
> These two changes make this patch not strictly a pure "refactor"
> patch, which IMHO should in no way change the calls being made nor
> the logical flow, only the code structure.


Got it. Will address in revision. Will wait for more reviews (if any) before re-spinning.

Thanks,
Beleswar

>
> Andrew
>
>>   }
>>     /*