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.poir...@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.anders...@linaro.org>
> ---
> 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
>
