netdev - [PATCH net-next 11/13] net: mscc: ocelot: rename variable 'cnt' in vcap_data_offset

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Date:   Wed, 30 Sep 2020 01:27:31 +0300
From:   Vladimir Oltean <vladimir.oltean@....com>
To:     davem@...emloft.net
Cc:     alexandre.belloni@...tlin.com, andrew@...n.ch,
        f.fainelli@...il.com, vivien.didelot@...il.com,
        horatiu.vultur@...rochip.com, joergen.andreasen@...rochip.com,
        allan.nielsen@...rochip.com, alexandru.marginean@....com,
        claudiu.manoil@....com, xiaoliang.yang_1@....com,
        hongbo.wang@....com, netdev@...r.kernel.org, kuba@...nel.org,
        UNGLinuxDriver@...rochip.com
Subject: [PATCH net-next 11/13] net: mscc: ocelot: rename variable 'cnt' in vcap_data_offset_get()

The 'cnt' variable is actually used for 2 purposes, to hold the number
of sub-words per VCAP entry, and the number of sub-words per VCAP
action.

In fact, I'm pretty sure these 2 numbers can never be different from one
another. By hardware definition, the entry (key) TCAM rows are divided
into the same number of sub-words as its associated action RAM rows.
But nonetheless, let's at least rename the variables such that
observations like this one are easier to make in the future.

Signed-off-by: Vladimir Oltean <vladimir.oltean@....com>
---
Changes since RFC v2:
Patch is new.

 drivers/net/ethernet/mscc/ocelot_vcap.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/mscc/ocelot_vcap.c b/drivers/net/ethernet/mscc/ocelot_vcap.c
index 1c732e3687d8..9e1b023f2d00 100644
--- a/drivers/net/ethernet/mscc/ocelot_vcap.c
+++ b/drivers/net/ethernet/mscc/ocelot_vcap.c
@@ -174,7 +174,8 @@ static void vcap_cache2action(struct ocelot *ocelot,
 static void vcap_data_offset_get(const struct vcap_props *vcap,
 				 struct vcap_data *data, int ix)
 {
-	int i, col, offset, num_entries_per_row, cnt, base;
+	int num_subwords_per_entry, num_subwords_per_action;
+	int i, col, offset, num_entries_per_row, base;
 	u32 width = vcap->tg_width;
 
 	switch (data->tg_sw) {
@@ -192,11 +193,12 @@ static void vcap_data_offset_get(const struct vcap_props *vcap,
 	}
 
 	col = (ix % num_entries_per_row);
-	cnt = (vcap->sw_count / num_entries_per_row);
-	base = (vcap->sw_count - col * cnt - cnt);
+	num_subwords_per_entry = (vcap->sw_count / num_entries_per_row);
+	base = (vcap->sw_count - col * num_subwords_per_entry -
+		num_subwords_per_entry);
 	data->tg_value = 0;
 	data->tg_mask = 0;
-	for (i = 0; i < cnt; i++) {
+	for (i = 0; i < num_subwords_per_entry; i++) {
 		offset = ((base + i) * width);
 		data->tg_value |= (data->tg_sw << offset);
 		data->tg_mask |= GENMASK(offset + width - 1, offset);
@@ -205,12 +207,14 @@ static void vcap_data_offset_get(const struct vcap_props *vcap,
 	/* Calculate key/action/counter offsets */
 	col = (num_entries_per_row - col - 1);
 	data->key_offset = (base * vcap->entry_width) / vcap->sw_count;
-	data->counter_offset = (cnt * col * vcap->counter_width);
+	data->counter_offset = (num_subwords_per_entry * col *
+				vcap->counter_width);
 	i = data->type;
 	width = vcap->action_table[i].width;
-	cnt = vcap->action_table[i].count;
-	data->action_offset = (((cnt * col * width) / num_entries_per_row) +
-			      vcap->action_type_width);
+	num_subwords_per_action = vcap->action_table[i].count;
+	data->action_offset = ((num_subwords_per_action * col * width) /
+				num_entries_per_row);
+	data->action_offset += vcap->action_type_width;
 }
 
 static void vcap_data_set(u32 *data, u32 offset, u32 len, u32 value)
-- 
2.25.1