From 3f48fab62bb81a7f9d01e9d43c40395fad011dd5 Mon Sep 17 00:00:00 2001 From: Stefan Chulski Date: Thu, 17 Dec 2020 20:30:17 +0200 Subject: net: mvpp2: Add TCAM entry to drop flow control pause frames Issue: Flow control frame used to pause GoP(MAC) was delivered to the CPU and created a load on the CPU. Since XOFF/XON frames are used only by MAC, these frames should be dropped inside MAC. Fix: According to 802.3-2012 - IEEE Standard for Ethernet pause frame has unique destination MAC address 01-80-C2-00-00-01. Add TCAM parser entry to track and drop pause frames by destination MAC. Fixes: 3f518509dedc ("ethernet: Add new driver for Marvell Armada 375 network unit") Signed-off-by: Stefan Chulski Link: https://lore.kernel.org/r/1608229817-21951-1-git-send-email-stefanc@marvell.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/marvell/mvpp2/mvpp2_prs.c | 33 ++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'drivers/net/ethernet/marvell/mvpp2/mvpp2_prs.c') diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_prs.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_prs.c index 5692c6087bbb..f069593d7e50 100644 --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_prs.c +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_prs.c @@ -405,6 +405,38 @@ static int mvpp2_prs_tcam_first_free(struct mvpp2 *priv, unsigned char start, return -EINVAL; } +/* Drop flow control pause frames */ +static void mvpp2_prs_drop_fc(struct mvpp2 *priv) +{ + unsigned char da[ETH_ALEN] = { 0x01, 0x80, 0xC2, 0x00, 0x00, 0x01 }; + struct mvpp2_prs_entry pe; + unsigned int len; + + memset(&pe, 0, sizeof(pe)); + + /* For all ports - drop flow control frames */ + pe.index = MVPP2_PE_FC_DROP; + mvpp2_prs_tcam_lu_set(&pe, MVPP2_PRS_LU_MAC); + + /* Set match on DA */ + len = ETH_ALEN; + while (len--) + mvpp2_prs_tcam_data_byte_set(&pe, len, da[len], 0xff); + + mvpp2_prs_sram_ri_update(&pe, MVPP2_PRS_RI_DROP_MASK, + MVPP2_PRS_RI_DROP_MASK); + + mvpp2_prs_sram_bits_set(&pe, MVPP2_PRS_SRAM_LU_GEN_BIT, 1); + mvpp2_prs_sram_next_lu_set(&pe, MVPP2_PRS_LU_FLOWS); + + /* Mask all ports */ + mvpp2_prs_tcam_port_map_set(&pe, MVPP2_PRS_PORT_MASK); + + /* Update shadow table and hw entry */ + mvpp2_prs_shadow_set(priv, pe.index, MVPP2_PRS_LU_MAC); + mvpp2_prs_hw_write(priv, &pe); +} + /* Enable/disable dropping all mac da's */ static void mvpp2_prs_mac_drop_all_set(struct mvpp2 *priv, int port, bool add) { @@ -1162,6 +1194,7 @@ static void mvpp2_prs_mac_init(struct mvpp2 *priv) mvpp2_prs_hw_write(priv, &pe); /* Create dummy entries for drop all and promiscuous modes */ + mvpp2_prs_drop_fc(priv); mvpp2_prs_mac_drop_all_set(priv, 0, false); mvpp2_prs_mac_promisc_set(priv, 0, MVPP2_PRS_L2_UNI_CAST, false); mvpp2_prs_mac_promisc_set(priv, 0, MVPP2_PRS_L2_MULTI_CAST, false); -- cgit