On Mon 01 Jun 10:55 PDT 2020, Mathieu Poirier wrote: > Introduce the required mechanic to set the state of the M4 in order > to properly deal with scenarios where the co-processor has been > stated by another entity. > > 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: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> > --- > drivers/remoteproc/stm32_rproc.c | 32 ++++++++++++++++++++++++++++++++ > 1 file changed, 32 insertions(+) > > diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c > index 80fd8fd831da..2154c8b90a2a 100644 > --- a/drivers/remoteproc/stm32_rproc.c > +++ b/drivers/remoteproc/stm32_rproc.c > @@ -38,6 +38,13 @@ > #define STM32_MBX_VQ1_ID 1 > #define STM32_MBX_SHUTDOWN "shutdown" > > +#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 +642,30 @@ 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) { > + /* > + * 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; > int ret; > > ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32)); > @@ -663,6 +688,13 @@ static int stm32_rproc_probe(struct platform_device *pdev) > if (ret) > goto free_rproc; > > + ret = stm32_rproc_get_m4_status(ddata, &state); > + if (ret) > + goto free_rproc; > + > + if (state == M4_STATE_CRUN) I presume this won't ever be e.g. M4_STATE_CRASH or M4_STATE_STANDBY? Regards, Bjorn > + rproc->state = RPROC_DETACHED; > + > rproc->has_iommu = false; > ddata->workqueue = create_workqueue(dev_name(dev)); > if (!ddata->workqueue) { > -- > 2.20.1 >
