[Skiboot] [PATCH v5 4/9] nest unit parser and nest mcs unit support functions

[Madhavan Srinivasan]

Add catalog parser function to detect Nest units. Add
support functions for nest memory control subsystem (mcs) unit.
Support function will add device tree node for each
event supported by mcs unit and corresponding reg, id, unit and scale
entries to pass on information about the event.

Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
---
 hw/nest.c | 160 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 160 insertions(+)

diff --git a/hw/nest.c b/hw/nest.c
index 142780845d3f..a7b5ae742eff 100644
--- a/hw/nest.c
+++ b/hw/nest.c
@@ -27,6 +27,8 @@
 #include <io.h>
 #include <platform.h>
 
+#define MAX_NAME_SIZE	64
+
 /*
  * Pointer holding the Catalog file in memory
  */
@@ -40,6 +42,157 @@ struct nest_catalog_desc *catalog_desc;
  */
 struct nest_catalog_page_0 *page0_desc;
 
+static u32 get_chip_event_offset(int idx, int domain)
+{
+	char *marker;
+	struct nest_catalog_events_data *ev;
+	int i;
+
+	if (domain == DOMAIN_CHIP)
+		marker = CHIP_EVENT_ENTRY(catalog_desc);
+	else
+		marker = CORE_EVENT_ENTRY(catalog_desc);
+
+	ev = (struct nest_catalog_events_data *)marker;
+	for (i = 0; i < idx ; i++) {
+		marker += ev->length;
+		ev = (struct nest_catalog_events_data *)marker;
+	}
+
+	return (ev->event_group_record_offs + ev->event_counter_offs);
+}
+
+static int dt_create_nest_unit_events(struct dt_node *pt, int index, u32 offset,
+					const char *name, const char *scale,
+					const char *unit)
+{
+	struct dt_node *type;
+
+	/*
+	 * Create an event node to pass event information.
+	 * "reg" property is must for event and rest of the properties
+	 * such as id, scale, unit are optional.
+	 */
+	type = dt_new_addr(pt, name, offset);
+	if (!type)
+		return -1;
+
+	/*
+	 * "reg" property:
+	 *
+	 * event offset where counter data gets accumulated
+	 */
+	dt_add_property_cells(type, "reg", offset, sizeof(u64));
+
+	/*
+	 * "id" property:
+	 *
+	 * event id to be appended to the event name. In some units like abus,
+	 * we have events such as abus0, abus1 and abus2. Since having numbers
+	 * in the dt node name are not suggested, we pass these numbers as
+	 * id peroperty.
+	 */
+	if (index >= 0)
+		 dt_add_property_cells(type, "id", index);
+
+	/*
+	 * "unit" and "scale" property:
+	 *
+	 * unit and scale properties, when used on raw counter value,
+	 * provide metric information.
+	 */
+	if (unit)
+		dt_add_property_string(type, "unit", unit);
+
+	if (scale)
+		dt_add_property_string(type, "scale", scale);
+
+	return 0;
+}
+
+static int dt_create_nest_mcs_node(struct dt_node *pt,
+		struct nest_catalog_group_data *gptr, const char *name)
+{
+	struct dt_node *type;
+	int idx;
+	u32 offset;
+	const char *unit = "MiB", *scale = "1.2207e-4";
+
+	type = dt_new(pt, name);
+	if (!type) {
+		prlog(PR_ERR, "nest_counters: %s type creation failed\n", name);
+		return -1;
+	}
+
+	dt_add_property_cells(type, "#address-cells", 1);
+	dt_add_property_cells(type, "#size-cells", 1);
+	dt_add_property(type, "ranges", NULL, 0);
+
+	for (idx = 0; idx < (gptr->event_count / 2); idx++) {
+		offset = get_chip_event_offset(gptr->event_index[idx],
+								DOMAIN_CHIP);
+		if (dt_create_nest_unit_events(type, idx, offset, "mcs", scale, unit))
+			return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Wrapper function to call corresponding nest unit functions
+ * for event dt creation. Not all the chip groups in the catalog are
+ * supported at this point.
+ */
+static int dt_create_nest_unit(struct dt_node *ima,
+				struct nest_catalog_group_data *gptr)
+{
+	char *name;
+
+	/*
+	 * Names provided in the catalog for each nest group/unit are
+	 * not valid device tree node names.
+	 */
+	const char mcs_read[] = "mcs_read", mcs_write[] = "mcs_write";
+
+	name = malloc(gptr->group_name_len);
+	if (!name)
+		return OPAL_NO_MEM;
+
+	memcpy((void *)name, (void *)gptr->remainder, gptr->group_name_len);
+	if (strstr(name, "MCS_Read_BW")) {
+		if (dt_create_nest_mcs_node(ima, gptr, mcs_read))
+			goto out;
+	} else if (strstr(name, "MCS_Write_BW")) {
+		if (dt_create_nest_mcs_node(ima, gptr, mcs_write))
+			goto out;
+	} else
+		free(name);
+
+	return OPAL_SUCCESS;
+out:
+	free(name);
+	return OPAL_RESOURCE;
+}
+
+static int detect_nest_units(struct dt_node *ima)
+{
+	struct nest_catalog_group_data *group_ptr;
+	char *marker;
+	int rc = CHIP_EVENTS_NOT_SUPPORTED;
+
+	marker = CHIP_GROUP_ENTRY(catalog_desc);
+	group_ptr = (struct nest_catalog_group_data *)marker;
+        while(group_ptr->domain == DOMAIN_CHIP) {
+		rc = dt_create_nest_unit(ima, group_ptr);
+		if (rc)
+			break;
+		marker += group_ptr->length;
+		group_ptr = (struct nest_catalog_group_data *)marker;
+	};
+
+	return rc;
+}
+
 int preload_catalog_lid()
 {
 	size_t size = NEST_CATALOG_SIZE;
@@ -173,6 +326,13 @@ void nest_pmu_init(int loaded)
 		dt_add_property_cells(chip_dev, "#size-cells", 1);
 		dt_add_property_cells(chip_dev, "ranges", 0, hi32(addr),
 						lo32(addr), SLW_IMA_SIZE);
+
+		/*
+		 * Now parse catalog and add nest units and their events
+		 * to the device tree.
+		 */
+		if (detect_nest_units(chip_dev))
+			goto fail;
 	}
 
 	return;
-- 
1.9.1