[Skiboot] [PATCH v2 07/11] Nest PowerBus unit support

[Madhavan Srinivasan]

Patch adds support for Nest PowerBus(PB) unit. PowerBus internal
and external bandwidth events are exported for now. Both unit and scale
information for each pb event passed as DT entry to kernel.

Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
---
 hw/nest.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/hw/nest.c b/hw/nest.c
index 01f5a6348f0f..dfebfb6ebf69 100644
--- a/hw/nest.c
+++ b/hw/nest.c
@@ -100,6 +100,56 @@ int dt_create_nest_chip_mcs_type( struct dt_node *ima,
 	return 0;
 }
 
+int dt_create_nest_chip_powerbus_event(struct dt_node *ima,
+                                u32 offset, const char *name)
+{
+	char ev_name[MAX_NAME_SIZE];
+	const char *unit = "MiB", *scale = "4.883e-4";
+
+	/* PowerBus BW DT for Internal/External BW */
+	snprintf(ev_name, MAX_NAME_SIZE, name);
+	dt_add_property_cells(ima, ev_name, offset);
+
+	/* Unit for the Event */
+	snprintf(ev_name, MAX_NAME_SIZE, "unit.%s.unit", name);
+	dt_add_property_string(ima, ev_name, unit);
+
+	/* Scale for the Event */
+	snprintf(ev_name, MAX_NAME_SIZE, "scale.%s.scale", name);
+	dt_add_property_string(ima, ev_name, scale);
+
+	return 0;
+}
+
+int dt_create_nest_chip_powerbus_type( struct dt_node *ima,
+			struct nest_catalogue_group_data *gptr, char *name)
+{
+	struct dt_node *type;
+	u32 offset;
+
+	type = dt_new(ima, name);
+	if (!type) {
+		prlog(PR_DEBUG, "ima %s type creation failed \n", name);
+		return -1;
+	}
+
+	/*
+	 * Incase of PowerBus(PB) Group, only Internal and External
+	 * transfer Bandwidth matters.
+	 */
+	dt_add_property_string(type, "device_type", "nest-ima-unit");
+
+	/* Create DT entry for PB Internal BW */
+	offset = get_chip_event_offset(gptr->event_index[2]);
+	dt_create_nest_chip_powerbus_event(type, offset, "Internal");
+
+	/* Create DT entry for PB External BW */
+	offset = get_chip_event_offset(gptr->event_index[3]);
+	dt_create_nest_chip_powerbus_event(type, offset, "External");
+
+	return 0;
+}
+
 /*
  * Wrapper Function to call Corresponding Nest unit functions
  * for event dt creation. Not all the Chip Groups in the Catalog are
@@ -118,6 +168,9 @@ int dt_create_nest_chip_type (struct dt_node *ima,
 	if (strstr(name, "MCS_")) {
 		if (dt_create_nest_chip_mcs_type(ima, gptr,name))
 			goto out;
+	} else if (strstr(name, "PowerBus_BW")) {
+		if (dt_create_nest_chip_powerbus_type(ima, gptr,name))
+			goto out;
 	} else
 		goto out;
 
-- 
1.9.1