[PATCH v9 3/3] remoteproc: zynqmp: parse TCM from device tree

[Tanmay Shah]

ZynqMP TCM information was fixed in driver. Now ZynqMP TCM information
is available in device-tree. Parse TCM information in driver
as per new bindings.

Signed-off-by: Tanmay Shah <tanmay.shah@xxxxxxx>
---

Changes in v9:
  - Introduce new API to request and release core1 TCM power-domains in
    lockstep mode. This will be used during prepare -> add_tcm_banks
    callback to enable TCM in lockstep mode.
  - Parse TCM from device-tree in lockstep mode and split mode in
    uniform way.
  - Fix TCM representation in device-tree in lockstep mode.

Changes in v8:
  - Remove pm_domains framework
  - Remove checking of pm_domain_id validation to power on/off tcm
  - Remove spurious change
  - parse power-domains property from device-tree and use EEMI calls
    to power on/off TCM instead of using pm domains framework

Changes in v7:
  - move checking of pm_domain_id from previous patch
  - fix mem_bank_data memory allocation

 drivers/remoteproc/xlnx_r5_remoteproc.c | 245 +++++++++++++++++++++++-
 1 file changed, 239 insertions(+), 6 deletions(-)

diff --git a/drivers/remoteproc/xlnx_r5_remoteproc.c b/drivers/remoteproc/xlnx_r5_remoteproc.c
index 4395edea9a64..0f87b984850b 100644
--- a/drivers/remoteproc/xlnx_r5_remoteproc.c
+++ b/drivers/remoteproc/xlnx_r5_remoteproc.c
@@ -74,8 +74,8 @@ struct mbox_info {
 };
 
 /*
- * Hardcoded TCM bank values. This will be removed once TCM bindings are
- * accepted for system-dt specifications and upstreamed in linux kernel
+ * Hardcoded TCM bank values. This will stay in driver to maintain backward
+ * compatibility with device-tree that does not have TCM information.
  */
 static const struct mem_bank_data zynqmp_tcm_banks_split[] = {
 	{0xffe00000UL, 0x0, 0x10000UL, PD_R5_0_ATCM, "atcm0"}, /* TCM 64KB each */
@@ -102,6 +102,7 @@ static const struct mem_bank_data zynqmp_tcm_banks_lockstep[] = {
  * @rproc: rproc handle
  * @pm_domain_id: RPU CPU power domain id
  * @ipi: pointer to mailbox information
+ * @lockstep_core1_np: second core's device_node to use in lockstep mode
  */
 struct zynqmp_r5_core {
 	struct device *dev;
@@ -111,6 +112,7 @@ struct zynqmp_r5_core {
 	struct rproc *rproc;
 	u32 pm_domain_id;
 	struct mbox_info *ipi;
+	struct device_node *lockstep_core1_np;
 };
 
 /**
@@ -539,6 +541,110 @@ static int tcm_mem_map(struct rproc *rproc,
 	return 0;
 }
 
+int request_core1_tcm_lockstep(struct rproc *rproc)
+{
+	struct zynqmp_r5_core *r5_core = rproc->priv;
+	struct of_phandle_args out_args = {0};
+	int ret, i, num_pd, pd_id, ret_err;
+	struct device_node *np;
+
+	np = r5_core->lockstep_core1_np;
+
+	/* Get number of power-domains */
+	num_pd = of_count_phandle_with_args(np, "power-domains",
+					    "#power-domain-cells");
+	if (num_pd <= 0)
+		return -EINVAL;
+
+	/* Get individual power-domain id and enable TCM */
+	for (i = 1; i < num_pd; i++) {
+		ret = of_parse_phandle_with_args(np, "power-domains",
+						 "#power-domain-cells",
+						 i, &out_args);
+		if (ret) {
+			dev_warn(r5_core->dev,
+				 "failed to get tcm %d in power-domains list, ret %d\n",
+				 i, ret);
+			goto fail_request_core1_tcm;
+		}
+
+		pd_id = out_args.args[0];
+		of_node_put(out_args.np);
+
+		ret = zynqmp_pm_request_node(pd_id, ZYNQMP_PM_CAPABILITY_ACCESS, 0,
+					     ZYNQMP_PM_REQUEST_ACK_BLOCKING);
+		if (ret) {
+			dev_err(r5_core->dev, "failed to request TCM node 0x%x\n",
+				pd_id);
+			goto fail_request_core1_tcm;
+		}
+	}
+
+	return 0;
+
+fail_request_core1_tcm:
+
+	/* Cache actual error to return later */
+	ret_err = ret;
+
+	/* Release previously requested TCM in case of failure */
+	while (--i > 0) {
+		ret = of_parse_phandle_with_args(np, "power-domains",
+						 "#power-domain-cells",
+						 i, &out_args);
+		if (ret)
+			return ret;
+		pd_id = out_args.args[0];
+		of_node_put(out_args.np);
+		zynqmp_pm_release_node(pd_id);
+	}
+
+	return ret_err;
+}
+
+void release_core1_tcm_lockstep(struct rproc *rproc)
+{
+	struct zynqmp_r5_core *r5_core = rproc->priv;
+	struct of_phandle_args out_args = {0};
+	struct zynqmp_r5_cluster *cluster;
+	int ret, i, num_pd, pd_id;
+	struct device_node *np;
+
+	/* Get R5 core1 node */
+	cluster = dev_get_drvdata(r5_core->dev->parent);
+
+	if (cluster->mode != LOCKSTEP_MODE)
+		return;
+
+	np = r5_core->lockstep_core1_np;
+
+	/* Get number of power-domains */
+	num_pd = of_count_phandle_with_args(np, "power-domains",
+					    "#power-domain-cells");
+	if (num_pd <= 0)
+		return;
+
+	/* Get individual power-domain id and turn off each TCM */
+	for (i = 1; i < num_pd; i++) {
+		ret = of_parse_phandle_with_args(np, "power-domains",
+						 "#power-domain-cells",
+						 i, &out_args);
+		if (ret) {
+			dev_warn(r5_core->dev,
+				 "failed to get pd of core1 tcm %d in list, ret %d\n",
+				 i, ret);
+			continue;
+		}
+
+		pd_id = out_args.args[0];
+		of_node_put(out_args.np);
+
+		if (zynqmp_pm_release_node(pd_id))
+			dev_warn(r5_core->dev,
+				 "failed to release core1 tcm pd 0x%x\n", pd_id);
+	}
+}
+
 /*
  * add_tcm_carveout_split_mode()
  * @rproc: single R5 core's corresponding rproc instance
@@ -633,6 +739,21 @@ static int add_tcm_carveout_lockstep_mode(struct rproc *rproc)
 	r5_core = rproc->priv;
 	dev = r5_core->dev;
 
+	/*
+	 * In lockstep mode, R5 core0 uses TCM of R5 core1 via aliased addresses.
+	 * Aliased addresses are contiguous with core0 TCM and embedded in "reg"
+	 * property. However, R5 core1 TCM power-domains needs to be requested
+	 * from firmware to use R5 core1 TCM. Request core1 TCM power-domains
+	 * if TCM is parsed from device-tree.
+	 */
+	if (of_find_property(r5_core->np, "reg", NULL)) {
+		ret = request_core1_tcm_lockstep(rproc);
+		if (ret) {
+			dev_err(r5_core->dev, "failed to request core1 TCM power-domains\n");
+			return ret;
+		}
+	}
+
 	/* Go through zynqmp banks for r5 node */
 	num_banks = r5_core->tcm_bank_count;
 
@@ -689,6 +810,9 @@ static int add_tcm_carveout_lockstep_mode(struct rproc *rproc)
 		pm_domain_id = r5_core->tcm_banks[i]->pm_domain_id;
 		zynqmp_pm_release_node(pm_domain_id);
 	}
+
+	release_core1_tcm_lockstep(rproc);
+
 	return ret;
 }
 
@@ -808,6 +932,8 @@ static int zynqmp_r5_rproc_unprepare(struct rproc *rproc)
 				 "can't turn off TCM bank 0x%x", pm_domain_id);
 	}
 
+	release_core1_tcm_lockstep(rproc);
+
 	return 0;
 }
 
@@ -878,6 +1004,95 @@ static struct zynqmp_r5_core *zynqmp_r5_add_rproc_core(struct device *cdev)
 	return ERR_PTR(ret);
 }
 
+static int zynqmp_r5_get_tcm_node_from_dt(struct zynqmp_r5_cluster *cluster)
+{
+	int i, j, tcm_bank_count, ret, tcm_pd_idx;
+	struct of_phandle_args out_args = {0};
+	struct zynqmp_r5_core *r5_core;
+	struct platform_device *cpdev;
+	struct mem_bank_data *tcm;
+	struct device_node *np;
+	struct resource *res;
+	u64 abs_addr, size;
+	struct device *dev;
+
+	for (i = 0; i < cluster->core_count; i++) {
+		r5_core = cluster->r5_cores[i];
+		dev = r5_core->dev;
+		np = r5_core->np;
+
+		/* we have address cell 2 and size cell as 2 */
+		tcm_bank_count = of_property_count_elems_of_size(np, "reg",
+								 4 * sizeof(u32));
+		if (tcm_bank_count <= 0) {
+			dev_err(dev, "can't get reg property err %d\n", tcm_bank_count);
+			return -EINVAL;
+		}
+
+		r5_core->tcm_banks = devm_kcalloc(dev, tcm_bank_count,
+						  sizeof(struct mem_bank_data *),
+						  GFP_KERNEL);
+		if (!r5_core->tcm_banks)
+			ret = -ENOMEM;
+
+		r5_core->tcm_bank_count = tcm_bank_count;
+		for (j = 0, tcm_pd_idx = 1; j < tcm_bank_count; j++, tcm_pd_idx++) {
+			tcm = devm_kzalloc(dev, sizeof(struct mem_bank_data),
+					   GFP_KERNEL);
+			if (!tcm)
+				return -ENOMEM;
+
+			r5_core->tcm_banks[j] = tcm;
+
+			/* Get power-domains id of TCM. */
+			ret = of_parse_phandle_with_args(np, "power-domains",
+							 "#power-domain-cells",
+							 tcm_pd_idx, &out_args);
+			if (ret) {
+				dev_err(r5_core->dev,
+					"failed to get tcm %d pm domain, ret %d\n",
+					tcm_pd_idx, ret);
+				return ret;
+			}
+			tcm->pm_domain_id = out_args.args[0];
+			of_node_put(out_args.np);
+
+			/* Get TCM address without translation. */
+			ret = of_property_read_reg(np, j, &abs_addr, &size);
+			if (ret) {
+				dev_err(dev, "failed to get reg property\n");
+				return ret;
+			}
+
+			/*
+			 * Remote processor can address only 32 bits
+			 * so convert 64-bits into 32-bits. This will discard
+			 * any unwanted upper 32-bits.
+			 */
+			tcm->da = (u32)abs_addr;
+			tcm->size = (u32)size;
+
+			cpdev = to_platform_device(dev);
+			res = platform_get_resource(cpdev, IORESOURCE_MEM, j);
+			if (!res) {
+				dev_err(dev, "failed to get tcm resource\n");
+				return -EINVAL;
+			}
+
+			tcm->addr = (u32)res->start;
+			tcm->bank_name = (char *)res->name;
+			res = devm_request_mem_region(dev, tcm->addr, tcm->size,
+						      tcm->bank_name);
+			if (!res) {
+				dev_err(dev, "failed to request tcm resource\n");
+				return -EINVAL;
+			}
+		}
+	}
+
+	return 0;
+}
+
 /**
  * zynqmp_r5_get_tcm_node()
  * Ideally this function should parse tcm node and store information
@@ -956,9 +1171,14 @@ static int zynqmp_r5_core_init(struct zynqmp_r5_cluster *cluster,
 	struct zynqmp_r5_core *r5_core;
 	int ret, i;
 
-	ret = zynqmp_r5_get_tcm_node(cluster);
-	if (ret < 0) {
-		dev_err(dev, "can't get tcm node, err %d\n", ret);
+	r5_core = cluster->r5_cores[0];
+	if (of_find_property(r5_core->np, "reg", NULL))
+		ret = zynqmp_r5_get_tcm_node_from_dt(cluster);
+	else
+		ret = zynqmp_r5_get_tcm_node(cluster);
+
+	if (ret) {
+		dev_err(dev, "can't get tcm, err %d\n", ret);
 		return ret;
 	}
 
@@ -1099,7 +1319,19 @@ static int zynqmp_r5_cluster_init(struct zynqmp_r5_cluster *cluster)
 		 * then ignore second child node.
 		 */
 		if (cluster_mode == LOCKSTEP_MODE) {
-			of_node_put(child);
+			/*
+			 * Get second core's device node only to use its power-domains.
+			 * Also, no need to use of_node_put on first core's device_node
+			 * as it is taken care by of_get_next_available_child.
+			 */
+			r5_cores[i]->lockstep_core1_np =
+				of_get_next_available_child(dev_node, child);
+
+			if (!r5_cores[i]->lockstep_core1_np) {
+				ret = -EINVAL;
+				goto release_r5_cores;
+			}
+
 			break;
 		}
 
@@ -1158,6 +1390,7 @@ static void zynqmp_r5_cluster_exit(void *data)
 		r5_core = cluster->r5_cores[i];
 		zynqmp_r5_free_mbox(r5_core->ipi);
 		of_reserved_mem_device_release(r5_core->dev);
+		of_node_put(r5_core->lockstep_core1_np);
 		put_device(r5_core->dev);
 		rproc_del(r5_core->rproc);
 		rproc_free(r5_core->rproc);
-- 
2.25.1