[PATCH v8 07/11] remoteproc: mediatek: Control SCP core 1 by rproc subdevice

From: Tinghan Shen
Date: Fri Mar 03 2023 - 03:35:00 EST


Register SCP core 1 as a subdevice of core 0 for the boot sequence
and watchdog timeout handling. The core 1 has to boot after core 0
because the SCP clock and SRAM power is controlled by SCP core 0.
As for watchdog timeout handling, the remoteproc framework helps to
stop/start subdevices automatically when SCP driver receives watchdog
timeout event.

Signed-off-by: Tinghan Shen <tinghan.shen@xxxxxxxxxxxx>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
---
drivers/remoteproc/mtk_common.h | 9 +++++
drivers/remoteproc/mtk_scp.c | 66 +++++++++++++++++++++++++++++++++
2 files changed, 75 insertions(+)

diff --git a/drivers/remoteproc/mtk_common.h b/drivers/remoteproc/mtk_common.h
index c088149e3dcc..f0c16553c00b 100644
--- a/drivers/remoteproc/mtk_common.h
+++ b/drivers/remoteproc/mtk_common.h
@@ -100,6 +100,13 @@ struct mtk_scp_of_data {
size_t ipi_buf_offset;
};

+struct mtk_scp_core_subdev {
+ struct rproc_subdev subdev;
+ struct mtk_scp *scp;
+};
+
+#define to_core_subdev(d) container_of(d, struct mtk_scp_core_subdev, subdev)
+
struct mtk_scp {
struct device *dev;
struct rproc *rproc;
@@ -132,6 +139,8 @@ struct mtk_scp {
struct list_head elem;
struct list_head cluster_cores;
struct list_head *cluster;
+
+ struct mtk_scp_core_subdev *core_subdev;
};

/**
diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
index 84103a70f426..0ee161c1478c 100644
--- a/drivers/remoteproc/mtk_scp.c
+++ b/drivers/remoteproc/mtk_scp.c
@@ -862,6 +862,60 @@ static void scp_remove_rpmsg_subdev(struct mtk_scp *scp)
}
}

+static int scp_core_subdev_start(struct rproc_subdev *subdev)
+{
+ struct mtk_scp_core_subdev *core_subdev = to_core_subdev(subdev);
+ struct mtk_scp *scp = core_subdev->scp;
+
+ rproc_boot(scp->rproc);
+
+ return 0;
+}
+
+static void scp_core_subdev_stop(struct rproc_subdev *subdev, bool crashed)
+{
+ struct mtk_scp_core_subdev *core_subdev = to_core_subdev(subdev);
+ struct mtk_scp *scp = core_subdev->scp;
+
+ rproc_shutdown(scp->rproc);
+}
+
+static int scp_core_subdev_register(struct mtk_scp *scp)
+{
+ struct device *dev = scp->dev;
+ struct mtk_scp_core_subdev *core_subdev;
+ struct mtk_scp *scp_c0;
+
+ scp_c0 = list_first_entry(scp->cluster, struct mtk_scp, elem);
+ if (!scp_c0)
+ return -ENODATA;
+
+ core_subdev = devm_kzalloc(dev, sizeof(*core_subdev), GFP_KERNEL);
+ if (!core_subdev)
+ return -ENOMEM;
+
+ core_subdev->scp = scp;
+ core_subdev->subdev.start = scp_core_subdev_start;
+ core_subdev->subdev.stop = scp_core_subdev_stop;
+
+ scp->core_subdev = core_subdev;
+ rproc_add_subdev(scp_c0->rproc, &scp->core_subdev->subdev);
+
+ return 0;
+}
+
+static void scp_core_subdev_unregister(struct mtk_scp *scp)
+{
+ struct mtk_scp *scp_c0;
+
+ if (scp->core_subdev) {
+ scp_c0 = list_first_entry(scp->cluster, struct mtk_scp, elem);
+ rproc_remove_subdev(scp_c0->rproc, &scp->core_subdev->subdev);
+ devm_kfree(scp->dev, scp->core_subdev);
+ scp->core_subdev = NULL;
+ }
+}
+
static int scp_rproc_init(struct platform_device *pdev,
struct mtk_scp_of_regs *of_regs,
const struct mtk_scp_of_data *of_data,
@@ -959,6 +1013,7 @@ static void scp_rproc_free(struct mtk_scp *scp)
{
int i;

+ scp_core_subdev_unregister(scp);
scp_remove_rpmsg_subdev(scp);
scp_ipi_unregister(scp, SCP_IPI_INIT);
scp_unmap_memory_region(scp);
@@ -1033,6 +1088,17 @@ static int scp_cluster_init(struct platform_device *pdev,
}

list_for_each_entry_safe_reverse(scp, temp, cluster, elem) {
+ if (!list_is_first(&scp->elem, cluster)) {
+ ret = scp_core_subdev_register(scp);
+ if (ret) {
+ dev_err_probe(scp->dev, ret, "Failed to register as subdev\n");
+ goto add_fail;
+ }
+
+ /* sub cores are booted as subdevices of core 0 */
+ scp->rproc->auto_boot = false;
+ }
+
ret = rproc_add(scp->rproc);
if (ret)
goto add_fail;
--
2.18.0