[PATCH v10 06/11] remoteproc: mediatek: Probe multi-core SCP

[Tinghan Shen]

The difference of single-core SCP and multi-core SCP device tree is
the presence of child device nodes described SCP cores. The SCP
driver populates the platform device and checks the child nodes
to identify whether it's a single-core SCP or a multi-core SCP.

Add the remoteproc instances for single-core SCP and multi-core SCP to
the new added SCP cluster list. When the SCP driver is removed, it
cleanup resources by walking through the cluster list.

Signed-off-by: Tinghan Shen <tinghan.shen@xxxxxxxxxxxx>
---
 drivers/remoteproc/mtk_common.h |   3 +
 drivers/remoteproc/mtk_scp.c    | 188 ++++++++++++++++++++++++++++----
 2 files changed, 172 insertions(+), 19 deletions(-)

diff --git a/drivers/remoteproc/mtk_common.h b/drivers/remoteproc/mtk_common.h
index c0905aec3b4b..b73b60c22ea1 100644
--- a/drivers/remoteproc/mtk_common.h
+++ b/drivers/remoteproc/mtk_common.h
@@ -128,6 +128,9 @@ struct mtk_scp {
 	size_t dram_size;
 
 	struct rproc_subdev *rpmsg_subdev;
+
+	struct list_head elem;
+	struct list_head *cluster;
 };
 
 /**
diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
index 5e4982f4d5dc..0b052b0acf2e 100644
--- a/drivers/remoteproc/mtk_scp.c
+++ b/drivers/remoteproc/mtk_scp.c
@@ -28,6 +28,7 @@ struct mtk_scp_of_cluster {
 	void __iomem *l1tcm_base;
 	size_t l1tcm_size;
 	phys_addr_t l1tcm_phys;
+	struct list_head mtk_scp_cluster;
 };
 
 /**
@@ -862,21 +863,31 @@ static void scp_remove_rpmsg_subdev(struct mtk_scp *scp)
 	}
 }
 
-static int scp_rproc_init(struct platform_device *pdev)
+static int scp_rproc_init(struct platform_device *cluster_pdev,
+			  struct platform_device *core_pdev,
+			  const struct mtk_scp_of_data *of_data)
 {
-	struct device *dev = &pdev->dev;
-	struct device_node *np = dev->of_node;
-	struct mtk_scp_of_cluster *of_cluster = platform_get_drvdata(pdev);
+	struct platform_device *pdev;
+	struct device *dev;
+	struct device_node *np;
+	struct mtk_scp_of_cluster *of_cluster = platform_get_drvdata(cluster_pdev);
 	struct mtk_scp *scp;
 	struct rproc *rproc;
 	struct resource *res;
 	const char *fw_name = "scp.img";
 	int ret, i;
 
+	if (core_pdev)
+		pdev = core_pdev;
+	else
+		pdev = cluster_pdev;
+
+	dev = &pdev->dev;
 	ret = rproc_of_parse_firmware(dev, 0, &fw_name);
 	if (ret < 0 && ret != -EINVAL)
 		return ret;
 
+	np = dev->of_node;
 	rproc = devm_rproc_alloc(dev, np->name, &scp_ops, fw_name, sizeof(*scp));
 	if (!rproc)
 		return dev_err_probe(dev, -ENOMEM, "unable to allocate remoteproc\n");
@@ -884,7 +895,7 @@ static int scp_rproc_init(struct platform_device *pdev)
 	scp = rproc->priv;
 	scp->rproc = rproc;
 	scp->dev = dev;
-	scp->data = of_device_get_match_data(dev);
+	scp->data = of_data;
 	platform_set_drvdata(pdev, scp);
 
 	scp->reg_base = of_cluster->reg_base;
@@ -934,10 +945,6 @@ static int scp_rproc_init(struct platform_device *pdev)
 		goto remove_subdev;
 	}
 
-	ret = rproc_add(rproc);
-	if (ret)
-		goto remove_subdev;
-
 	return 0;
 
 remove_subdev:
@@ -952,6 +959,121 @@ static int scp_rproc_init(struct platform_device *pdev)
 	return ret;
 }
 
+static void scp_rproc_free(struct mtk_scp *scp)
+{
+	int i;
+
+	scp_remove_rpmsg_subdev(scp);
+	scp_ipi_unregister(scp, SCP_IPI_INIT);
+	scp_unmap_memory_region(scp);
+	for (i = 0; i < SCP_IPI_MAX; i++)
+		mutex_destroy(&scp->ipi_desc[i].lock);
+	mutex_destroy(&scp->send_lock);
+}
+
+static int scp_is_single_core(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev_of_node(dev);
+	struct device_node *child;
+
+	child = of_get_next_available_child(np, NULL);
+	if (!child)
+		return dev_err_probe(dev, -ENODEV, "No child node\n");
+
+	of_node_put(child);
+	return of_node_name_eq(child, "cros-ec-rpmsg");
+}
+
+static int scp_cluster_init(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev_of_node(dev);
+	struct platform_device *cpdev;
+	struct device_node *child;
+	struct mtk_scp_of_cluster *of_cluster = platform_get_drvdata(pdev);
+	const struct mtk_scp_of_data **cluster_of_data;
+	struct list_head *cluster = &of_cluster->mtk_scp_cluster;
+	struct mtk_scp *scp, *temp;
+	int core_id = 0;
+	int ret;
+
+	ret = scp_is_single_core(pdev);
+	if (ret < 0)
+		return ret;
+
+	if (ret) {
+		dev_dbg(dev, "single-core scp\n");
+
+		/* When using the SCP node phandle on exported SCP APIs, the drvdata
+		 * is expected to be the mtk_scp object, and as a result, it is intended
+		 * to be overwritten for single-core SCP usage.
+		 */
+		ret = scp_rproc_init(pdev, NULL, of_device_get_match_data(dev));
+		if (ret)
+			return dev_err_probe(dev, ret, "Failed to initialize single-core scp\n");
+
+		scp = platform_get_drvdata(pdev);
+		list_add_tail(&scp->elem, cluster);
+		scp->cluster = cluster;
+	} else {
+		dev_dbg(dev, "multi-core scp\n");
+
+		cluster_of_data = (const struct mtk_scp_of_data **)of_device_get_match_data(dev);
+
+		for_each_available_child_of_node(np, child) {
+			if (!cluster_of_data[core_id]) {
+				ret = -EINVAL;
+				dev_err(dev, "Not support core %d\n", core_id);
+				of_node_put(child);
+				goto init_fail;
+			}
+
+			cpdev = of_find_device_by_node(child);
+			if (!cpdev) {
+				ret = -ENODEV;
+				dev_err(dev, "Not found platform device for core %d\n", core_id);
+				of_node_put(child);
+				goto init_fail;
+			}
+
+			ret = scp_rproc_init(pdev, cpdev, cluster_of_data[core_id]);
+			if (ret) {
+				dev_err(dev, "Failed to initialize core %d rproc\n", core_id);
+				put_device(&cpdev->dev);
+				of_node_put(child);
+				goto init_fail;
+			}
+			scp = platform_get_drvdata(cpdev);
+			list_add_tail(&scp->elem, cluster);
+			scp->cluster = cluster;
+			put_device(&cpdev->dev);
+
+			core_id++;
+		}
+	}
+
+	list_for_each_entry_safe_reverse(scp, temp, cluster, elem) {
+		ret = rproc_add(scp->rproc);
+		if (ret)
+			goto add_fail;
+	}
+
+	return 0;
+
+add_fail:
+	list_for_each_entry_continue(scp, cluster, elem) {
+		rproc_del(scp->rproc);
+	}
+init_fail:
+	list_for_each_entry_safe_reverse(scp, temp, cluster, elem) {
+		list_del(&scp->elem);
+		scp_rproc_free(scp);
+	}
+
+	return ret;
+}
+
 static int scp_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -983,23 +1105,44 @@ static int scp_probe(struct platform_device *pdev)
 		of_cluster->l1tcm_phys = res->start;
 	}
 
+	INIT_LIST_HEAD(&of_cluster->mtk_scp_cluster);
 	platform_set_drvdata(pdev, of_cluster);
 
-	return scp_rproc_init(pdev);
+	ret = devm_of_platform_populate(dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to populate platform devices\n");
+
+	ret = scp_cluster_init(pdev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to initialize scp cluster\n");
+
+	return 0;
 }
 
 static int scp_remove(struct platform_device *pdev)
 {
-	struct mtk_scp *scp = platform_get_drvdata(pdev);
-	int i;
+	struct mtk_scp *scp, *temp;
+	struct mtk_scp_of_cluster *of_cluster;
+	struct list_head *cluster;
+	int ret;
 
-	rproc_del(scp->rproc);
-	scp_remove_rpmsg_subdev(scp);
-	scp_ipi_unregister(scp, SCP_IPI_INIT);
-	scp_unmap_memory_region(scp);
-	for (i = 0; i < SCP_IPI_MAX; i++)
-		mutex_destroy(&scp->ipi_desc[i].lock);
-	mutex_destroy(&scp->send_lock);
+	ret = scp_is_single_core(pdev);
+	if (ret < 0)
+		return ret;
+
+	if (ret) {
+		scp = platform_get_drvdata(pdev);
+		cluster = scp->cluster;
+	} else {
+		of_cluster = platform_get_drvdata(pdev);
+		cluster = &of_cluster->mtk_scp_cluster;
+	}
+
+	list_for_each_entry_safe_reverse(scp, temp, cluster, elem) {
+		list_del(&scp->elem);
+		rproc_del(scp->rproc);
+		scp_rproc_free(scp);
+	}
 
 	return 0;
 }
@@ -1078,12 +1221,19 @@ static const struct mtk_scp_of_data mt8195_of_data_c1 = {
 	.host_to_scp_int_bit = MT8195_CORE1_HOST_IPC_INT_BIT,
 };
 
+static const struct mtk_scp_of_data *mt8195_of_data_cores[] = {
+	&mt8195_of_data,
+	&mt8195_of_data_c1,
+	NULL
+};
+
 static const struct of_device_id mtk_scp_of_match[] = {
 	{ .compatible = "mediatek,mt8183-scp", .data = &mt8183_of_data },
 	{ .compatible = "mediatek,mt8186-scp", .data = &mt8186_of_data },
 	{ .compatible = "mediatek,mt8188-scp", .data = &mt8188_of_data },
 	{ .compatible = "mediatek,mt8192-scp", .data = &mt8192_of_data },
 	{ .compatible = "mediatek,mt8195-scp", .data = &mt8195_of_data },
+	{ .compatible = "mediatek,mt8195-scp-dual", .data = &mt8195_of_data_cores },
 	{},
 };
 MODULE_DEVICE_TABLE(of, mtk_scp_of_match);
-- 
2.18.0