The code to calculate the hardware register enumerator
for the maximum L3 length isn't entirely simple to read.
Use the existing defines and rewrite the function into a
table look-up.
Acked-by: Michał Mirosław
Signed-off-by: Linus Walleij
---
ChangeLog v2->v3:
- Collected Michał's ACK.
ChangeLog v1->v2:
- No changes, just resending with the rest.
---
drivers/net/ethernet/cortina/gemini.c | 61 ---
1 file changed, 46 insertions(+), 15 deletions(-)
diff --git a/drivers/net/ethernet/cortina/gemini.c
b/drivers/net/ethernet/cortina/gemini.c
index 6d7404f66f84..8fc31723f700 100644
--- a/drivers/net/ethernet/cortina/gemini.c
+++ b/drivers/net/ethernet/cortina/gemini.c
@@ -401,26 +401,57 @@ static int gmac_setup_phy(struct net_device *netdev)
return 0;
}
-static int gmac_pick_rx_max_len(int max_l3_len)
-{
- /* index = CONFIG_MAXLEN_XXX values */
- static const int max_len[8] = {
- 1536, 1518, 1522, 1542,
- 9212, 10236, 1518, 1518
- };
- int i, n = 5;
+/* The maximum frame length is not logically enumerated in the
+ * hardware, so we do a table lookup to find the applicable max
+ * frame length.
+ */
+struct gmac_max_framelen {
+ unsigned int max_l3_len;
+ u8 val;
+};
- max_l3_len += ETH_HLEN + VLAN_HLEN;
+static const struct gmac_max_framelen gmac_maxlens[] = {
+ {
+ .max_l3_len = 1518,
+ .val = CONFIG0_MAXLEN_1518,
+ },
+ {
+ .max_l3_len = 1522,
+ .val = CONFIG0_MAXLEN_1522,
+ },
+ {
+ .max_l3_len = 1536,
+ .val = CONFIG0_MAXLEN_1536,
+ },
+ {
+ .max_l3_len = 1542,
+ .val = CONFIG0_MAXLEN_1542,
+ },
+ {
+ .max_l3_len = 9212,
+ .val = CONFIG0_MAXLEN_9k,
+ },
+ {
+ .max_l3_len = 10236,
+ .val = CONFIG0_MAXLEN_10k,
+ },
+};
+
+static int gmac_pick_rx_max_len(unsigned int max_l3_len)
+{
+ const struct gmac_max_framelen *maxlen;
+ int maxtot;
+ int i;
- if (max_l3_len > max_len[n])
- return -1;
+ maxtot = max_l3_len + ETH_HLEN + VLAN_HLEN;
- for (i = 0; i < 5; i++) {
- if (max_len[i] >= max_l3_len && max_len[i] < max_len[n])
- n = i;
+ for (i = 0; i < ARRAY_SIZE(gmac_maxlens); i++) {
+ maxlen = _maxlens[i];
+ if (maxtot <= maxlen->max_l3_len)
+ return maxlen->val;
}
- return n;
+ return -1;
}
static int gmac_init(struct net_device *netdev)
--
2.17.1
