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authorJakub Kicinski <jakub.kicinski@netronome.com>2019-10-21 20:16:12 -0700
committerJakub Kicinski <jakub.kicinski@netronome.com>2019-10-21 20:16:12 -0700
commit39438490c9714378148f3b603f635362c8780b51 (patch)
tree6d826c30f12de986b4ecb29f5e5ae39551623921 /drivers/net/ethernet/intel/igc/igc_mac.c
parent985fd98ab5cc04994a38f928942048c8743a1f04 (diff)
parent70332577e4d9ee343a7d57a7721c858172e5925c (diff)
Merge branch '1GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue
Jeff Kirsher says: ==================== 1GbE Intel Wired LAN Driver Updates 2019-10-21 This series contains updates to e1000e and igc only. Sasha adds stream control transmission protocol (SCTP) CRC checksum support for igc. Also added S0ix support to the e1000e driver. Then added multicast support by adding the address list to the MTA table and providing the option for IPv6 address for igc. In addition, added receive checksum support to igc as well. Lastly, cleaned up some code that was not fully implemented yet for the VLAN filter table array. v2: Dropped patch 1 & 2 from the original series. Patch 1 is being sent to 'net' tree as a fix and patch 2 implementation needs to be re-worked. Updated the patch to add support for S0ix to fix the reverse Xmas tree issues and made the entry/exit functions void since they constantly returned success. All based on community feedback. v3: Cleaned up patch 4 of the series based on feedback from the community. Cleaned up a stray comma in a code comment and removed the 'inline' of a function that would be inlined by the compiler anyways. ==================== Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Diffstat (limited to 'drivers/net/ethernet/intel/igc/igc_mac.c')
-rw-r--r--drivers/net/ethernet/intel/igc/igc_mac.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/drivers/net/ethernet/intel/igc/igc_mac.c b/drivers/net/ethernet/intel/igc/igc_mac.c
index 5eeb4c8caf4a..12aa6b5fcb5d 100644
--- a/drivers/net/ethernet/intel/igc/igc_mac.c
+++ b/drivers/net/ethernet/intel/igc/igc_mac.c
@@ -784,3 +784,107 @@ bool igc_enable_mng_pass_thru(struct igc_hw *hw)
out:
return ret_val;
}
+
+/**
+ * igc_hash_mc_addr - Generate a multicast hash value
+ * @hw: pointer to the HW structure
+ * @mc_addr: pointer to a multicast address
+ *
+ * Generates a multicast address hash value which is used to determine
+ * the multicast filter table array address and new table value. See
+ * igc_mta_set()
+ **/
+static u32 igc_hash_mc_addr(struct igc_hw *hw, u8 *mc_addr)
+{
+ u32 hash_value, hash_mask;
+ u8 bit_shift = 0;
+
+ /* Register count multiplied by bits per register */
+ hash_mask = (hw->mac.mta_reg_count * 32) - 1;
+
+ /* For a mc_filter_type of 0, bit_shift is the number of left-shifts
+ * where 0xFF would still fall within the hash mask.
+ */
+ while (hash_mask >> bit_shift != 0xFF)
+ bit_shift++;
+
+ /* The portion of the address that is used for the hash table
+ * is determined by the mc_filter_type setting.
+ * The algorithm is such that there is a total of 8 bits of shifting.
+ * The bit_shift for a mc_filter_type of 0 represents the number of
+ * left-shifts where the MSB of mc_addr[5] would still fall within
+ * the hash_mask. Case 0 does this exactly. Since there are a total
+ * of 8 bits of shifting, then mc_addr[4] will shift right the
+ * remaining number of bits. Thus 8 - bit_shift. The rest of the
+ * cases are a variation of this algorithm...essentially raising the
+ * number of bits to shift mc_addr[5] left, while still keeping the
+ * 8-bit shifting total.
+ *
+ * For example, given the following Destination MAC Address and an
+ * MTA register count of 128 (thus a 4096-bit vector and 0xFFF mask),
+ * we can see that the bit_shift for case 0 is 4. These are the hash
+ * values resulting from each mc_filter_type...
+ * [0] [1] [2] [3] [4] [5]
+ * 01 AA 00 12 34 56
+ * LSB MSB
+ *
+ * case 0: hash_value = ((0x34 >> 4) | (0x56 << 4)) & 0xFFF = 0x563
+ * case 1: hash_value = ((0x34 >> 3) | (0x56 << 5)) & 0xFFF = 0xAC6
+ * case 2: hash_value = ((0x34 >> 2) | (0x56 << 6)) & 0xFFF = 0x163
+ * case 3: hash_value = ((0x34 >> 0) | (0x56 << 8)) & 0xFFF = 0x634
+ */
+ switch (hw->mac.mc_filter_type) {
+ default:
+ case 0:
+ break;
+ case 1:
+ bit_shift += 1;
+ break;
+ case 2:
+ bit_shift += 2;
+ break;
+ case 3:
+ bit_shift += 4;
+ break;
+ }
+
+ hash_value = hash_mask & (((mc_addr[4] >> (8 - bit_shift)) |
+ (((u16)mc_addr[5]) << bit_shift)));
+
+ return hash_value;
+}
+
+/**
+ * igc_update_mc_addr_list - Update Multicast addresses
+ * @hw: pointer to the HW structure
+ * @mc_addr_list: array of multicast addresses to program
+ * @mc_addr_count: number of multicast addresses to program
+ *
+ * Updates entire Multicast Table Array.
+ * The caller must have a packed mc_addr_list of multicast addresses.
+ **/
+void igc_update_mc_addr_list(struct igc_hw *hw,
+ u8 *mc_addr_list, u32 mc_addr_count)
+{
+ u32 hash_value, hash_bit, hash_reg;
+ int i;
+
+ /* clear mta_shadow */
+ memset(&hw->mac.mta_shadow, 0, sizeof(hw->mac.mta_shadow));
+
+ /* update mta_shadow from mc_addr_list */
+ for (i = 0; (u32)i < mc_addr_count; i++) {
+ hash_value = igc_hash_mc_addr(hw, mc_addr_list);
+
+ hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
+ hash_bit = hash_value & 0x1F;
+
+ hw->mac.mta_shadow[hash_reg] |= BIT(hash_bit);
+ mc_addr_list += ETH_ALEN;
+ }
+
+ /* replace the entire MTA table */
+ for (i = hw->mac.mta_reg_count - 1; i >= 0; i--)
+ array_wr32(IGC_MTA, i, hw->mac.mta_shadow[i]);
+ wrfl();
+}