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

Mathieu Poirier
2020-04-24T20:25:47Z

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@linaro.org>
Reviewed-by: Loic Pallardy <loic.pallardy@st.com>
---
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);
+}
+
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;
+ }
+
rproc->auto_boot = auto_boot;
rproc->has_iommu = false;
ddata->workqueue = create_workqueue(dev_name(dev));
--
2.20.1