amd-xgbe: Add support for VLAN filtering

This patch adds support for (imperfect) filtering of
VLAN tag ids using a 16-bit filter hash table.  When
VLANs are added, a 4-bit hash is calculated with the
result indicating the bit in the hash table to set.
This table is used by the hardware to drop packets with
a VLAN id that does not hash to a set bit in the table.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Lendacky, Thomas
2014-06-24 16:19:24 -05:00
committed by David S. Miller
parent c52e9c6385
commit 801c62d945
6 changed files with 165 additions and 14 deletions
+95
View File
@@ -116,6 +116,7 @@
#include <linux/phy.h>
#include <linux/clk.h>
#include <linux/bitrev.h>
#include "xgbe.h"
#include "xgbe-common.h"
@@ -738,6 +739,89 @@ static int xgbe_disable_rx_vlan_stripping(struct xgbe_prv_data *pdata)
return 0;
}
static int xgbe_enable_rx_vlan_filtering(struct xgbe_prv_data *pdata)
{
/* Enable VLAN filtering */
XGMAC_IOWRITE_BITS(pdata, MAC_PFR, VTFE, 1);
/* Enable VLAN Hash Table filtering */
XGMAC_IOWRITE_BITS(pdata, MAC_VLANTR, VTHM, 1);
/* Disable VLAN tag inverse matching */
XGMAC_IOWRITE_BITS(pdata, MAC_VLANTR, VTIM, 0);
/* Only filter on the lower 12-bits of the VLAN tag */
XGMAC_IOWRITE_BITS(pdata, MAC_VLANTR, ETV, 1);
/* In order for the VLAN Hash Table filtering to be effective,
* the VLAN tag identifier in the VLAN Tag Register must not
* be zero. Set the VLAN tag identifier to "1" to enable the
* VLAN Hash Table filtering. This implies that a VLAN tag of
* 1 will always pass filtering.
*/
XGMAC_IOWRITE_BITS(pdata, MAC_VLANTR, VL, 1);
return 0;
}
static int xgbe_disable_rx_vlan_filtering(struct xgbe_prv_data *pdata)
{
/* Disable VLAN filtering */
XGMAC_IOWRITE_BITS(pdata, MAC_PFR, VTFE, 0);
return 0;
}
#ifndef CRCPOLY_LE
#define CRCPOLY_LE 0xedb88320
#endif
static u32 xgbe_vid_crc32_le(__le16 vid_le)
{
u32 poly = CRCPOLY_LE;
u32 crc = ~0;
u32 temp = 0;
unsigned char *data = (unsigned char *)&vid_le;
unsigned char data_byte = 0;
int i, bits;
bits = get_bitmask_order(VLAN_VID_MASK);
for (i = 0; i < bits; i++) {
if ((i % 8) == 0)
data_byte = data[i / 8];
temp = ((crc & 1) ^ data_byte) & 1;
crc >>= 1;
data_byte >>= 1;
if (temp)
crc ^= poly;
}
return crc;
}
static int xgbe_update_vlan_hash_table(struct xgbe_prv_data *pdata)
{
u32 crc;
u16 vid;
__le16 vid_le;
u16 vlan_hash_table = 0;
/* Generate the VLAN Hash Table value */
for_each_set_bit(vid, pdata->active_vlans, VLAN_N_VID) {
/* Get the CRC32 value of the VLAN ID */
vid_le = cpu_to_le16(vid);
crc = bitrev32(~xgbe_vid_crc32_le(vid_le)) >> 28;
vlan_hash_table |= (1 << crc);
}
/* Set the VLAN Hash Table filtering register */
XGMAC_IOWRITE_BITS(pdata, MAC_VLANHTR, VLHT, vlan_hash_table);
return 0;
}
static void xgbe_tx_desc_reset(struct xgbe_ring_data *rdata)
{
struct xgbe_ring_desc *rdesc = rdata->rdesc;
@@ -1547,6 +1631,14 @@ static void xgbe_config_vlan_support(struct xgbe_prv_data *pdata)
XGMAC_IOWRITE_BITS(pdata, MAC_VLANIR, CSVL, 0);
XGMAC_IOWRITE_BITS(pdata, MAC_VLANIR, VLTI, 1);
/* Set the current VLAN Hash Table register value */
xgbe_update_vlan_hash_table(pdata);
if (pdata->netdev->features & NETIF_F_HW_VLAN_CTAG_FILTER)
xgbe_enable_rx_vlan_filtering(pdata);
else
xgbe_disable_rx_vlan_filtering(pdata);
if (pdata->netdev->features & NETIF_F_HW_VLAN_CTAG_RX)
xgbe_enable_rx_vlan_stripping(pdata);
else
@@ -2118,6 +2210,9 @@ void xgbe_init_function_ptrs_dev(struct xgbe_hw_if *hw_if)
hw_if->enable_rx_vlan_stripping = xgbe_enable_rx_vlan_stripping;
hw_if->disable_rx_vlan_stripping = xgbe_disable_rx_vlan_stripping;
hw_if->enable_rx_vlan_filtering = xgbe_enable_rx_vlan_filtering;
hw_if->disable_rx_vlan_filtering = xgbe_disable_rx_vlan_filtering;
hw_if->update_vlan_hash_table = xgbe_update_vlan_hash_table;
hw_if->read_mmd_regs = xgbe_read_mmd_regs;
hw_if->write_mmd_regs = xgbe_write_mmd_regs;