Re: [PATCH v2 06/12] remoteproc: stm32: Get coprocessor state

[Mathieu Poirier]

On Wed, Apr 29, 2020 at 03:38:24PM +0200, Arnaud POULIQUEN wrote:
> 
> 
> On 4/24/20 10:24 PM, Mathieu Poirier wrote:
> > Introduce the required mechanic to get the state of the M4 when the
> > remoteproc core is initialising.
> > 
> > Mainly based on the work published by Arnaud Pouliquen [1].
> > 
> > [1]. https://patchwork.kernel.org/project/linux-remoteproc/list/?series=239877
> > 
> > Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> > Reviewed-by: Loic Pallardy <loic.pallardy@xxxxxx>
> > ---
> >  drivers/remoteproc/stm32_rproc.c | 29 +++++++++++++++++++++++++++++
> >  1 file changed, 29 insertions(+)
> > 
> > diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c
> > index a285f338bed8..89fbd2ffac93 100644
> > --- a/drivers/remoteproc/stm32_rproc.c
> > +++ b/drivers/remoteproc/stm32_rproc.c
> > @@ -38,6 +38,15 @@
> >  #define STM32_MBX_VQ1_ID	1
> >  #define STM32_MBX_SHUTDOWN	"shutdown"
> >  
> > +#define RSC_TBL_SIZE		(1024)
> > +
> > +#define M4_STATE_OFF		0
> > +#define M4_STATE_INI		1
> > +#define M4_STATE_CRUN		2
> > +#define M4_STATE_CSTOP		3
> > +#define M4_STATE_STANDBY	4
> > +#define M4_STATE_CRASH		5
> > +
> >  struct stm32_syscon {
> >  	struct regmap *map;
> >  	u32 reg;
> > @@ -635,12 +644,23 @@ static int stm32_rproc_parse_dt(struct platform_device *pdev,
> >  	return 0;
> >  }
> >  
> > +static int stm32_rproc_get_m4_status(struct stm32_rproc *ddata,
> > +				     unsigned int *state)
> > +{
> > +	/* See stm32_rproc_parse_dt() */
> > +	if (!ddata->m4_state.map)
> > +		return -EINVAL;
> > +
> > +	return regmap_read(ddata->m4_state.map, ddata->m4_state.reg, state);
> > +}
> i would manage here the default state depending on the error types
> if (!ddata->m4_state.map {
> 	/* 
> 	 * We couldn't get the coprocessor's state, assume
> 	 * it is not running.
> 	 */
> 	state = M4_STATE_OFF;
> 
> 	return 0;
> }
> 
> return regmap_read(ddata->m4_state.map, ddata->m4_state.reg, state);
> 
> 
> 
> > +
> >  static int stm32_rproc_probe(struct platform_device *pdev)
> >  {
> >  	struct device *dev = &pdev->dev;
> >  	struct stm32_rproc *ddata;
> >  	struct device_node *np = dev->of_node;
> >  	struct rproc *rproc;
> > +	unsigned int state;
> >  	bool auto_boot = false;
> >  	int ret;
> >  
> > @@ -664,6 +684,15 @@ static int stm32_rproc_probe(struct platform_device *pdev)
> >  	if (ret)
> >  		goto free_rproc;
> >  
> > +	ret = stm32_rproc_get_m4_status(ddata, &state);
> > +	if (ret) {
> > +		/*
> > +		 * We couldn't get the coprocessor's state, assume
> > +		 * it is not running.
> > +		 */
> > +		state = M4_STATE_OFF;
> 
> So here just handle the error;

Ok

> 
> Regards
> Arnaud
> > +	}
> > +
> >  	rproc->auto_boot = auto_boot;
> >  	rproc->has_iommu = false;
> >  	ddata->workqueue = create_workqueue(dev_name(dev));
> >