From cedca4180127e097e4823018e748b1635c0667f0 Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Wed, 11 Jul 2018 21:32:41 +0200 Subject: net: gemini: Look up L3 maxlen from table MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: David S. Miller --- drivers/net/ethernet/cortina/gemini.c | 61 ++++++++++++++++++++++++++--------- 1 file changed, 46 insertions(+), 15 deletions(-) (limited to 'drivers/net/ethernet/cortina/gemini.c') diff --git a/drivers/net/ethernet/cortina/gemini.c b/drivers/net/ethernet/cortina/gemini.c index ce1f04fdbf70..2f502c42a653 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 = &gmac_maxlens[i]; + if (maxtot <= maxlen->max_l3_len) + return maxlen->val; } - return n; + return -1; } static int gmac_init(struct net_device *netdev) -- cgit v1.2.3-59-g8ed1b