net: mvpp2: debugfs: add entries for classifier flows

The classifier configuration for RSS is quite complex, with several
lookup tables being used. This commit adds useful info in debugfs to
see how the different tables are configured :

Added 2 new entries in the per-port directory :

  - .../eth0/default_rxq : The default rx queue on that port
  - .../eth0/rss_enable : Indicates if RSS is enabled in the C2 entry

Added the 'flows' directory :

  It contains one entry per sub-flow. a 'sub-flow' is a unique path from
  Header Parser to the flow table. Multiple sub-flows can point to the
  same 'flow' (each flow has an id from 8 to 29, which is its index in the
  Lookup Id table) :

  - .../flows/00/...
             /01/...
             ...
             /51/id : The flow id. There are 21 unique flows. There's one
                       flow per combination of the following parameters :
                       - L4 protocol (TCP, UDP, none)
                       - L3 protocol (IPv4, IPv6)
                       - L3 parameters (Fragmented or not)
                       - L2 parameters (Vlan tag presence or not)
              .../type : The flow type. This is an even higher level flow,
                         that we manipulate with ethtool. It can be :
                         "udp4" "tcp4" "udp6" "tcp6" "ipv4" "ipv6" "other".
              .../eth0/...
              .../eth1/engine : The hash generation engine used for this
	                        flow on the given port
                  .../hash_opts : The hash generation options indicating on
                                  what data we base the hash (vlan tag, src
                                  IP, src port, etc.)
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvpp2/mvpp2.h

@@ -132,8 +132,10 @@
 #define MVPP22_CLS_C2_ATTR0			0x1b64
 #define     MVPP22_CLS_C2_ATTR0_QHIGH(qh)	(((qh) & 0x1f) << 24)
 #define     MVPP22_CLS_C2_ATTR0_QHIGH_MASK	0x1f
+#define     MVPP22_CLS_C2_ATTR0_QHIGH_OFFS	24
 #define     MVPP22_CLS_C2_ATTR0_QLOW(ql)	(((ql) & 0x7) << 21)
 #define     MVPP22_CLS_C2_ATTR0_QLOW_MASK	0x7
+#define     MVPP22_CLS_C2_ATTR0_QLOW_OFFS	21
 #define MVPP22_CLS_C2_ATTR1			0x1b68
 #define MVPP22_CLS_C2_ATTR2			0x1b6c
 #define     MVPP22_CLS_C2_ATTR2_RSS_EN		BIT(30)

drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.c

@@ -322,8 +322,8 @@ static struct mvpp2_cls_flow cls_flows[MVPP2_N_FLOWS] = {
 		       0, 0),
 };
 
-static void mvpp2_cls_flow_read(struct mvpp2 *priv, int index,
-				struct mvpp2_cls_flow_entry *fe)
+void mvpp2_cls_flow_read(struct mvpp2 *priv, int index,
+			 struct mvpp2_cls_flow_entry *fe)
 {
 	fe->index = index;
 	mvpp2_write(priv, MVPP2_CLS_FLOW_INDEX_REG, index);
@@ -342,6 +342,18 @@ static void mvpp2_cls_flow_write(struct mvpp2 *priv,
 	mvpp2_write(priv, MVPP2_CLS_FLOW_TBL2_REG,  fe->data[2]);
 }
 
+void mvpp2_cls_lookup_read(struct mvpp2 *priv, int lkpid, int way,
+			   struct mvpp2_cls_lookup_entry *le)
+{
+	u32 val;
+
+	val = (way << MVPP2_CLS_LKP_INDEX_WAY_OFFS) | lkpid;
+	mvpp2_write(priv, MVPP2_CLS_LKP_INDEX_REG, val);
+	le->way = way;
+	le->lkpid = lkpid;
+	le->data = mvpp2_read(priv, MVPP2_CLS_LKP_TBL_REG);
+}
+
 /* Update classification lookup table register */
 static void mvpp2_cls_lookup_write(struct mvpp2 *priv,
 				   struct mvpp2_cls_lookup_entry *le)
@@ -388,6 +400,12 @@ static void mvpp2_cls_flow_eng_set(struct mvpp2_cls_flow_entry *fe,
 	fe->data[0] |= MVPP2_CLS_FLOW_TBL0_ENG(engine);
 }
 
+int mvpp2_cls_flow_eng_get(struct mvpp2_cls_flow_entry *fe)
+{
+	return (fe->data[0] >> MVPP2_CLS_FLOW_TBL0_OFFS) &
+		MVPP2_CLS_FLOW_TBL0_ENG_MASK;
+}
+
 static void mvpp2_cls_flow_port_id_sel(struct mvpp2_cls_flow_entry *fe,
 				       bool from_packet)
 {
@@ -554,7 +572,7 @@ static int mvpp2_flow_set_hek_fields(struct mvpp2_cls_flow_entry *fe,
 	return 0;
 }
 
-static struct mvpp2_cls_flow *mvpp2_cls_flow_get(int flow)
+struct mvpp2_cls_flow *mvpp2_cls_flow_get(int flow)
 {
 	if (flow >= MVPP2_N_FLOWS)
 		return NULL;
@@ -725,8 +743,8 @@ static void mvpp2_cls_c2_write(struct mvpp2 *priv,
 	mvpp2_write(priv, MVPP22_CLS_C2_ATTR3, c2->attr[3]);
 }
 
-static void mvpp2_cls_c2_read(struct mvpp2 *priv, int index,
-			      struct mvpp2_cls_c2_entry *c2)
+void mvpp2_cls_c2_read(struct mvpp2 *priv, int index,
+		       struct mvpp2_cls_c2_entry *c2)
 {
 	mvpp2_write(priv, MVPP22_CLS_C2_TCAM_IDX, index);
 

drivers/net/ethernet/marvell/mvpp2/mvpp2_cls.h

@@ -209,4 +209,19 @@ void mvpp2_cls_port_config(struct mvpp2_port *port);
 
 void mvpp2_cls_oversize_rxq_set(struct mvpp2_port *port);
 
+int mvpp2_cls_flow_eng_get(struct mvpp2_cls_flow_entry *fe);
+
+u16 mvpp2_flow_get_hek_fields(struct mvpp2_cls_flow_entry *fe);
+
+struct mvpp2_cls_flow *mvpp2_cls_flow_get(int flow);
+
+void mvpp2_cls_flow_read(struct mvpp2 *priv, int index,
+			 struct mvpp2_cls_flow_entry *fe);
+
+void mvpp2_cls_lookup_read(struct mvpp2 *priv, int lkpid, int way,
+			   struct mvpp2_cls_lookup_entry *le);
+
+void mvpp2_cls_c2_read(struct mvpp2 *priv, int index,
+		       struct mvpp2_cls_c2_entry *c2);
+
 #endif

drivers/net/ethernet/marvell/mvpp2/mvpp2_debugfs.c

@@ -11,12 +11,207 @@
 
 #include "mvpp2.h"
 #include "mvpp2_prs.h"
+#include "mvpp2_cls.h"
 
 struct mvpp2_dbgfs_prs_entry {
 	int tid;
 	struct mvpp2 *priv;
 };
 
+struct mvpp2_dbgfs_flow_entry {
+	int flow;
+	struct mvpp2 *priv;
+};
+
+struct mvpp2_dbgfs_port_flow_entry {
+	struct mvpp2_port *port;
+	struct mvpp2_dbgfs_flow_entry *dbg_fe;
+};
+
+static int mvpp2_dbgfs_flow_type_show(struct seq_file *s, void *unused)
+{
+	struct mvpp2_dbgfs_flow_entry *entry = s->private;
+	struct mvpp2_cls_flow *f;
+	const char *flow_name;
+
+	f = mvpp2_cls_flow_get(entry->flow);
+	if (!f)
+		return -EINVAL;
+
+	switch (f->flow_type) {
+	case IPV4_FLOW:
+		flow_name = "ipv4";
+		break;
+	case IPV6_FLOW:
+		flow_name = "ipv6";
+		break;
+	case TCP_V4_FLOW:
+		flow_name = "tcp4";
+		break;
+	case TCP_V6_FLOW:
+		flow_name = "tcp6";
+		break;
+	case UDP_V4_FLOW:
+		flow_name = "udp4";
+		break;
+	case UDP_V6_FLOW:
+		flow_name = "udp6";
+		break;
+	default:
+		flow_name = "other";
+	}
+
+	seq_printf(s, "%s\n", flow_name);
+
+	return 0;
+}
+
+static int mvpp2_dbgfs_flow_type_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, mvpp2_dbgfs_flow_type_show, inode->i_private);
+}
+
+static int mvpp2_dbgfs_flow_type_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq = file->private_data;
+	struct mvpp2_dbgfs_flow_entry *flow_entry = seq->private;
+
+	kfree(flow_entry);
+	return single_release(inode, file);
+}
+
+static const struct file_operations mvpp2_dbgfs_flow_type_fops = {
+	.open = mvpp2_dbgfs_flow_type_open,
+	.read = seq_read,
+	.release = mvpp2_dbgfs_flow_type_release,
+};
+
+static int mvpp2_dbgfs_flow_id_show(struct seq_file *s, void *unused)
+{
+	struct mvpp2_dbgfs_flow_entry *entry = s->private;
+	struct mvpp2_cls_flow *f;
+
+	f = mvpp2_cls_flow_get(entry->flow);
+	if (!f)
+		return -EINVAL;
+
+	seq_printf(s, "%d\n", f->flow_id);
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(mvpp2_dbgfs_flow_id);
+
+static int mvpp2_dbgfs_port_flow_hash_opt_show(struct seq_file *s, void *unused)
+{
+	struct mvpp2_dbgfs_port_flow_entry *entry = s->private;
+	struct mvpp2_port *port = entry->port;
+	struct mvpp2_cls_flow_entry fe;
+	struct mvpp2_cls_flow *f;
+	int flow_index;
+	u16 hash_opts;
+
+	f = mvpp2_cls_flow_get(entry->dbg_fe->flow);
+	if (!f)
+		return -EINVAL;
+
+	flow_index = MVPP2_PORT_FLOW_HASH_ENTRY(entry->port->id, f->flow_id);
+
+	mvpp2_cls_flow_read(port->priv, flow_index, &fe);
+
+	hash_opts = mvpp2_flow_get_hek_fields(&fe);
+
+	seq_printf(s, "0x%04x\n", hash_opts);
+
+	return 0;
+}
+
+static int mvpp2_dbgfs_port_flow_hash_opt_open(struct inode *inode,
+					       struct file *file)
+{
+	return single_open(file, mvpp2_dbgfs_port_flow_hash_opt_show,
+			   inode->i_private);
+}
+
+static int mvpp2_dbgfs_port_flow_hash_opt_release(struct inode *inode,
+						  struct file *file)
+{
+	struct seq_file *seq = file->private_data;
+	struct mvpp2_dbgfs_port_flow_entry *flow_entry = seq->private;
+
+	kfree(flow_entry);
+	return single_release(inode, file);
+}
+
+static const struct file_operations mvpp2_dbgfs_port_flow_hash_opt_fops = {
+	.open = mvpp2_dbgfs_port_flow_hash_opt_open,
+	.read = seq_read,
+	.release = mvpp2_dbgfs_port_flow_hash_opt_release,
+};
+
+static int mvpp2_dbgfs_port_flow_engine_show(struct seq_file *s, void *unused)
+{
+	struct mvpp2_dbgfs_port_flow_entry *entry = s->private;
+	struct mvpp2_port *port = entry->port;
+	struct mvpp2_cls_flow_entry fe;
+	struct mvpp2_cls_flow *f;
+	int flow_index, engine;
+
+	f = mvpp2_cls_flow_get(entry->dbg_fe->flow);
+	if (!f)
+		return -EINVAL;
+
+	flow_index = MVPP2_PORT_FLOW_HASH_ENTRY(entry->port->id, f->flow_id);
+
+	mvpp2_cls_flow_read(port->priv, flow_index, &fe);
+
+	engine = mvpp2_cls_flow_eng_get(&fe);
+
+	seq_printf(s, "%d\n", engine);
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(mvpp2_dbgfs_port_flow_engine);
+
+static int mvpp2_dbgfs_flow_c2_rxq_show(struct seq_file *s, void *unused)
+{
+	struct mvpp2_port *port = s->private;
+	struct mvpp2_cls_c2_entry c2;
+	u8 qh, ql;
+
+	mvpp2_cls_c2_read(port->priv, MVPP22_CLS_C2_RSS_ENTRY(port->id), &c2);
+
+	qh = (c2.attr[0] >> MVPP22_CLS_C2_ATTR0_QHIGH_OFFS) &
+	     MVPP22_CLS_C2_ATTR0_QHIGH_MASK;
+
+	ql = (c2.attr[0] >> MVPP22_CLS_C2_ATTR0_QLOW_OFFS) &
+	     MVPP22_CLS_C2_ATTR0_QLOW_MASK;
+
+	seq_printf(s, "%d\n", (qh << 3 | ql));
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(mvpp2_dbgfs_flow_c2_rxq);
+
+static int mvpp2_dbgfs_flow_c2_enable_show(struct seq_file *s, void *unused)
+{
+	struct mvpp2_port *port = s->private;
+	struct mvpp2_cls_c2_entry c2;
+	int enabled;
+
+	mvpp2_cls_c2_read(port->priv, MVPP22_CLS_C2_RSS_ENTRY(port->id), &c2);
+
+	enabled = !!(c2.attr[2] | MVPP22_CLS_C2_ATTR2_RSS_EN);
+
+	seq_printf(s, "%d\n", enabled);
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(mvpp2_dbgfs_flow_c2_enable);
+
 static int mvpp2_dbgfs_port_vid_show(struct seq_file *s, void *unused)
 {
 	struct mvpp2_port *port = s->private;
@@ -239,6 +434,90 @@ static const struct file_operations mvpp2_dbgfs_prs_valid_fops = {
 	.release = mvpp2_dbgfs_prs_valid_release,
 };
 
+static int mvpp2_dbgfs_flow_port_init(struct dentry *parent,
+				      struct mvpp2_port *port,
+				      struct mvpp2_dbgfs_flow_entry *entry)
+{
+	struct mvpp2_dbgfs_port_flow_entry *port_entry;
+	struct dentry *port_dir;
+
+	port_dir = debugfs_create_dir(port->dev->name, parent);
+	if (IS_ERR(port_dir))
+		return PTR_ERR(port_dir);
+
+	/* This will be freed by 'hash_opts' release op */
+	port_entry = kmalloc(sizeof(*port_entry), GFP_KERNEL);
+	if (!port_entry)
+		return -ENOMEM;
+
+	port_entry->port = port;
+	port_entry->dbg_fe = entry;
+
+	debugfs_create_file("hash_opts", 0444, port_dir, port_entry,
+			    &mvpp2_dbgfs_port_flow_hash_opt_fops);
+
+	debugfs_create_file("engine", 0444, port_dir, port_entry,
+			    &mvpp2_dbgfs_port_flow_engine_fops);
+
+	return 0;
+}
+
+static int mvpp2_dbgfs_flow_entry_init(struct dentry *parent,
+				       struct mvpp2 *priv, int flow)
+{
+	struct mvpp2_dbgfs_flow_entry *entry;
+	struct dentry *flow_entry_dir;
+	char flow_entry_name[10];
+	int i, ret;
+
+	sprintf(flow_entry_name, "%02d", flow);
+
+	flow_entry_dir = debugfs_create_dir(flow_entry_name, parent);
+	if (!flow_entry_dir)
+		return -ENOMEM;
+
+	/* This will be freed by 'type' release op */
+	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	entry->flow = flow;
+	entry->priv = priv;
+
+	debugfs_create_file("type", 0444, flow_entry_dir, entry,
+			    &mvpp2_dbgfs_flow_type_fops);
+
+	debugfs_create_file("id", 0444, flow_entry_dir, entry,
+			    &mvpp2_dbgfs_flow_id_fops);
+
+	/* Create entry for each port */
+	for (i = 0; i < priv->port_count; i++) {
+		ret = mvpp2_dbgfs_flow_port_init(flow_entry_dir,
+						 priv->port_list[i], entry);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+static int mvpp2_dbgfs_flow_init(struct dentry *parent, struct mvpp2 *priv)
+{
+	struct dentry *flow_dir;
+	int i, ret;
+
+	flow_dir = debugfs_create_dir("flows", parent);
+	if (!flow_dir)
+		return -ENOMEM;
+
+	for (i = 0; i < MVPP2_N_FLOWS; i++) {
+		ret = mvpp2_dbgfs_flow_entry_init(flow_dir, priv, i);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 static int mvpp2_dbgfs_prs_entry_init(struct dentry *parent,
 				      struct mvpp2 *priv, int tid)
 {
@@ -321,6 +600,12 @@ static int mvpp2_dbgfs_port_init(struct dentry *parent,
 	debugfs_create_file("vid_filter", 0444, port_dir, port,
 			    &mvpp2_dbgfs_port_vid_fops);
 
+	debugfs_create_file("default_rxq", 0444, port_dir, port,
+			    &mvpp2_dbgfs_flow_c2_rxq_fops);
+
+	debugfs_create_file("rss_enable", 0444, port_dir, port,
+			    &mvpp2_dbgfs_flow_c2_enable_fops);
+
 	return 0;
 }
 
@@ -357,6 +642,10 @@ void mvpp2_dbgfs_init(struct mvpp2 *priv, const char *name)
 			goto err;
 	}
 
+	ret = mvpp2_dbgfs_flow_init(mvpp2_dir, priv);
+	if (ret)
+		goto err;
+
 	return;
 err:
 	mvpp2_dbgfs_cleanup(priv);