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path: root/drivers/net/ethernet/intel/igc/igc_mac.c
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Diffstat (limited to 'drivers/net/ethernet/intel/igc/igc_mac.c')
-rw-r--r--drivers/net/ethernet/intel/igc/igc_mac.c555
1 files changed, 310 insertions, 245 deletions
diff --git a/drivers/net/ethernet/intel/igc/igc_mac.c b/drivers/net/ethernet/intel/igc/igc_mac.c
index f7683d3ae47c..7ac6637f8db7 100644
--- a/drivers/net/ethernet/intel/igc/igc_mac.c
+++ b/drivers/net/ethernet/intel/igc/igc_mac.c
@@ -7,10 +7,6 @@
#include "igc_mac.h"
#include "igc_hw.h"
-/* forward declaration */
-static s32 igc_set_default_fc(struct igc_hw *hw);
-static s32 igc_set_fc_watermarks(struct igc_hw *hw);
-
/**
* igc_disable_pcie_master - Disables PCI-express master access
* @hw: pointer to the HW structure
@@ -76,6 +72,41 @@ void igc_init_rx_addrs(struct igc_hw *hw, u16 rar_count)
}
/**
+ * igc_set_fc_watermarks - Set flow control high/low watermarks
+ * @hw: pointer to the HW structure
+ *
+ * Sets the flow control high/low threshold (watermark) registers. If
+ * flow control XON frame transmission is enabled, then set XON frame
+ * transmission as well.
+ */
+static s32 igc_set_fc_watermarks(struct igc_hw *hw)
+{
+ u32 fcrtl = 0, fcrth = 0;
+
+ /* Set the flow control receive threshold registers. Normally,
+ * these registers will be set to a default threshold that may be
+ * adjusted later by the driver's runtime code. However, if the
+ * ability to transmit pause frames is not enabled, then these
+ * registers will be set to 0.
+ */
+ if (hw->fc.current_mode & igc_fc_tx_pause) {
+ /* We need to set up the Receive Threshold high and low water
+ * marks as well as (optionally) enabling the transmission of
+ * XON frames.
+ */
+ fcrtl = hw->fc.low_water;
+ if (hw->fc.send_xon)
+ fcrtl |= IGC_FCRTL_XONE;
+
+ fcrth = hw->fc.high_water;
+ }
+ wr32(IGC_FCRTL, fcrtl);
+ wr32(IGC_FCRTH, fcrth);
+
+ return 0;
+}
+
+/**
* igc_setup_link - Setup flow control and link settings
* @hw: pointer to the HW structure
*
@@ -96,13 +127,10 @@ s32 igc_setup_link(struct igc_hw *hw)
goto out;
/* If requested flow control is set to default, set flow control
- * based on the EEPROM flow control settings.
+ * to both 'rx' and 'tx' pause frames.
*/
- if (hw->fc.requested_mode == igc_fc_default) {
- ret_val = igc_set_default_fc(hw);
- if (ret_val)
- goto out;
- }
+ if (hw->fc.requested_mode == igc_fc_default)
+ hw->fc.requested_mode = igc_fc_full;
/* We want to save off the original Flow Control configuration just
* in case we get disconnected and then reconnected into a different
@@ -136,19 +164,6 @@ out:
}
/**
- * igc_set_default_fc - Set flow control default values
- * @hw: pointer to the HW structure
- *
- * Read the EEPROM for the default values for flow control and store the
- * values.
- */
-static s32 igc_set_default_fc(struct igc_hw *hw)
-{
- hw->fc.requested_mode = igc_fc_full;
- return 0;
-}
-
-/**
* igc_force_mac_fc - Force the MAC's flow control settings
* @hw: pointer to the HW structure
*
@@ -178,7 +193,7 @@ s32 igc_force_mac_fc(struct igc_hw *hw)
* 1: Rx flow control is enabled (we can receive pause
* frames but not send pause frames).
* 2: Tx flow control is enabled (we can send pause frames
- * frames but we do not receive pause frames).
+ * but we do not receive pause frames).
* 3: Both Rx and TX flow control (symmetric) is enabled.
* other: No other values should be possible at this point.
*/
@@ -212,41 +227,6 @@ out:
}
/**
- * igc_set_fc_watermarks - Set flow control high/low watermarks
- * @hw: pointer to the HW structure
- *
- * Sets the flow control high/low threshold (watermark) registers. If
- * flow control XON frame transmission is enabled, then set XON frame
- * transmission as well.
- */
-static s32 igc_set_fc_watermarks(struct igc_hw *hw)
-{
- u32 fcrtl = 0, fcrth = 0;
-
- /* Set the flow control receive threshold registers. Normally,
- * these registers will be set to a default threshold that may be
- * adjusted later by the driver's runtime code. However, if the
- * ability to transmit pause frames is not enabled, then these
- * registers will be set to 0.
- */
- if (hw->fc.current_mode & igc_fc_tx_pause) {
- /* We need to set up the Receive Threshold high and low water
- * marks as well as (optionally) enabling the transmission of
- * XON frames.
- */
- fcrtl = hw->fc.low_water;
- if (hw->fc.send_xon)
- fcrtl |= IGC_FCRTL_XONE;
-
- fcrth = hw->fc.high_water;
- }
- wr32(IGC_FCRTL, fcrtl);
- wr32(IGC_FCRTH, fcrth);
-
- return 0;
-}
-
-/**
* igc_clear_hw_cntrs_base - Clear base hardware counters
* @hw: pointer to the HW structure
*
@@ -255,15 +235,14 @@ static s32 igc_set_fc_watermarks(struct igc_hw *hw)
void igc_clear_hw_cntrs_base(struct igc_hw *hw)
{
rd32(IGC_CRCERRS);
- rd32(IGC_SYMERRS);
rd32(IGC_MPC);
rd32(IGC_SCC);
rd32(IGC_ECOL);
rd32(IGC_MCC);
rd32(IGC_LATECOL);
rd32(IGC_COLC);
+ rd32(IGC_RERC);
rd32(IGC_DC);
- rd32(IGC_SEC);
rd32(IGC_RLEC);
rd32(IGC_XONRXC);
rd32(IGC_XONTXC);
@@ -308,31 +287,20 @@ void igc_clear_hw_cntrs_base(struct igc_hw *hw)
rd32(IGC_ALGNERRC);
rd32(IGC_RXERRC);
rd32(IGC_TNCRS);
- rd32(IGC_CEXTERR);
+ rd32(IGC_HTDPMC);
rd32(IGC_TSCTC);
- rd32(IGC_TSCTFC);
rd32(IGC_MGTPRC);
rd32(IGC_MGTPDC);
rd32(IGC_MGTPTC);
rd32(IGC_IAC);
- rd32(IGC_ICRXOC);
- rd32(IGC_ICRXPTC);
- rd32(IGC_ICRXATC);
- rd32(IGC_ICTXPTC);
- rd32(IGC_ICTXATC);
- rd32(IGC_ICTXQEC);
- rd32(IGC_ICTXQMTC);
- rd32(IGC_ICRXDMTC);
-
- rd32(IGC_CBTMPC);
- rd32(IGC_HTDPMC);
- rd32(IGC_CBRMPC);
rd32(IGC_RPTHC);
+ rd32(IGC_TLPIC);
+ rd32(IGC_RLPIC);
rd32(IGC_HGPTC);
- rd32(IGC_HTCBDPC);
+ rd32(IGC_RXDMTC);
rd32(IGC_HGORCL);
rd32(IGC_HGORCH);
rd32(IGC_HGOTCL);
@@ -387,8 +355,8 @@ void igc_rar_set(struct igc_hw *hw, u8 *addr, u32 index)
s32 igc_check_for_copper_link(struct igc_hw *hw)
{
struct igc_mac_info *mac = &hw->mac;
+ bool link = false;
s32 ret_val;
- bool link;
/* We only want to go out to the PHY registers to see if Auto-Neg
* has completed and/or if our link status has changed. The
@@ -418,14 +386,6 @@ s32 igc_check_for_copper_link(struct igc_hw *hw)
*/
igc_check_downshift(hw);
- /* If we are forcing speed/duplex, then we simply return since
- * we have already determined whether we have link or not.
- */
- if (!mac->autoneg) {
- ret_val = -IGC_ERR_CONFIG;
- goto out;
- }
-
/* Auto-Neg is enabled. Auto Speed Detection takes care
* of MAC speed/duplex configuration. So we only need to
* configure Collision Distance in the MAC.
@@ -442,6 +402,11 @@ s32 igc_check_for_copper_link(struct igc_hw *hw)
hw_dbg("Error configuring flow control\n");
out:
+ /* Now that we are aware of our link settings, we can set the LTR
+ * thresholds.
+ */
+ ret_val = igc_set_ltr_i225(hw, link);
+
return ret_val;
}
@@ -487,187 +452,183 @@ s32 igc_config_fc_after_link_up(struct igc_hw *hw)
* so we had to force link. In this case, we need to force the
* configuration of the MAC to match the "fc" parameter.
*/
- if (mac->autoneg_failed) {
- if (hw->phy.media_type == igc_media_type_copper)
- ret_val = igc_force_mac_fc(hw);
- }
+ if (mac->autoneg_failed)
+ ret_val = igc_force_mac_fc(hw);
if (ret_val) {
hw_dbg("Error forcing flow control settings\n");
goto out;
}
- /* Check for the case where we have copper media and auto-neg is
- * enabled. In this case, we need to check and see if Auto-Neg
- * has completed, and if so, how the PHY and link partner has
- * flow control configured.
+ /* In auto-neg, we need to check and see if Auto-Neg has completed,
+ * and if so, how the PHY and link partner has flow control
+ * configured.
*/
- if (hw->phy.media_type == igc_media_type_copper && mac->autoneg) {
- /* Read the MII Status Register and check to see if AutoNeg
- * has completed. We read this twice because this reg has
- * some "sticky" (latched) bits.
- */
- ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
- &mii_status_reg);
- if (ret_val)
- goto out;
- ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
- &mii_status_reg);
- if (ret_val)
- goto out;
- if (!(mii_status_reg & MII_SR_AUTONEG_COMPLETE)) {
- hw_dbg("Copper PHY and Auto Neg has not completed.\n");
- goto out;
- }
+ /* Read the MII Status Register and check to see if AutoNeg
+ * has completed. We read this twice because this reg has
+ * some "sticky" (latched) bits.
+ */
+ ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
+ &mii_status_reg);
+ if (ret_val)
+ goto out;
+ ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
+ &mii_status_reg);
+ if (ret_val)
+ goto out;
- /* The AutoNeg process has completed, so we now need to
- * read both the Auto Negotiation Advertisement
- * Register (Address 4) and the Auto_Negotiation Base
- * Page Ability Register (Address 5) to determine how
- * flow control was negotiated.
- */
- ret_val = hw->phy.ops.read_reg(hw, PHY_AUTONEG_ADV,
- &mii_nway_adv_reg);
- if (ret_val)
- goto out;
- ret_val = hw->phy.ops.read_reg(hw, PHY_LP_ABILITY,
- &mii_nway_lp_ability_reg);
- if (ret_val)
- goto out;
- /* Two bits in the Auto Negotiation Advertisement Register
- * (Address 4) and two bits in the Auto Negotiation Base
- * Page Ability Register (Address 5) determine flow control
- * for both the PHY and the link partner. The following
- * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
- * 1999, describes these PAUSE resolution bits and how flow
- * control is determined based upon these settings.
- * NOTE: DC = Don't Care
- *
- * LOCAL DEVICE | LINK PARTNER
- * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
- *-------|---------|-------|---------|--------------------
- * 0 | 0 | DC | DC | igc_fc_none
- * 0 | 1 | 0 | DC | igc_fc_none
- * 0 | 1 | 1 | 0 | igc_fc_none
- * 0 | 1 | 1 | 1 | igc_fc_tx_pause
- * 1 | 0 | 0 | DC | igc_fc_none
- * 1 | DC | 1 | DC | igc_fc_full
- * 1 | 1 | 0 | 0 | igc_fc_none
- * 1 | 1 | 0 | 1 | igc_fc_rx_pause
- *
- * Are both PAUSE bits set to 1? If so, this implies
- * Symmetric Flow Control is enabled at both ends. The
- * ASM_DIR bits are irrelevant per the spec.
- *
- * For Symmetric Flow Control:
- *
- * LOCAL DEVICE | LINK PARTNER
- * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
- *-------|---------|-------|---------|--------------------
- * 1 | DC | 1 | DC | IGC_fc_full
- *
- */
- if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
- (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE)) {
- /* Now we need to check if the user selected RX ONLY
- * of pause frames. In this case, we had to advertise
- * FULL flow control because we could not advertise RX
- * ONLY. Hence, we must now check to see if we need to
- * turn OFF the TRANSMISSION of PAUSE frames.
- */
- if (hw->fc.requested_mode == igc_fc_full) {
- hw->fc.current_mode = igc_fc_full;
- hw_dbg("Flow Control = FULL.\n");
- } else {
- hw->fc.current_mode = igc_fc_rx_pause;
- hw_dbg("Flow Control = RX PAUSE frames only.\n");
- }
- }
+ if (!(mii_status_reg & MII_SR_AUTONEG_COMPLETE)) {
+ hw_dbg("Copper PHY and Auto Neg has not completed.\n");
+ goto out;
+ }
- /* For receiving PAUSE frames ONLY.
- *
- * LOCAL DEVICE | LINK PARTNER
- * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
- *-------|---------|-------|---------|--------------------
- * 0 | 1 | 1 | 1 | igc_fc_tx_pause
- */
- else if (!(mii_nway_adv_reg & NWAY_AR_PAUSE) &&
- (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
- (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
- (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
- hw->fc.current_mode = igc_fc_tx_pause;
- hw_dbg("Flow Control = TX PAUSE frames only.\n");
- }
- /* For transmitting PAUSE frames ONLY.
- *
- * LOCAL DEVICE | LINK PARTNER
- * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
- *-------|---------|-------|---------|--------------------
- * 1 | 1 | 0 | 1 | igc_fc_rx_pause
- */
- else if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
- (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
- !(mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
- (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
- hw->fc.current_mode = igc_fc_rx_pause;
- hw_dbg("Flow Control = RX PAUSE frames only.\n");
- }
- /* Per the IEEE spec, at this point flow control should be
- * disabled. However, we want to consider that we could
- * be connected to a legacy switch that doesn't advertise
- * desired flow control, but can be forced on the link
- * partner. So if we advertised no flow control, that is
- * what we will resolve to. If we advertised some kind of
- * receive capability (Rx Pause Only or Full Flow Control)
- * and the link partner advertised none, we will configure
- * ourselves to enable Rx Flow Control only. We can do
- * this safely for two reasons: If the link partner really
- * didn't want flow control enabled, and we enable Rx, no
- * harm done since we won't be receiving any PAUSE frames
- * anyway. If the intent on the link partner was to have
- * flow control enabled, then by us enabling RX only, we
- * can at least receive pause frames and process them.
- * This is a good idea because in most cases, since we are
- * predominantly a server NIC, more times than not we will
- * be asked to delay transmission of packets than asking
- * our link partner to pause transmission of frames.
+ /* The AutoNeg process has completed, so we now need to
+ * read both the Auto Negotiation Advertisement
+ * Register (Address 4) and the Auto_Negotiation Base
+ * Page Ability Register (Address 5) to determine how
+ * flow control was negotiated.
+ */
+ ret_val = hw->phy.ops.read_reg(hw, PHY_AUTONEG_ADV,
+ &mii_nway_adv_reg);
+ if (ret_val)
+ goto out;
+ ret_val = hw->phy.ops.read_reg(hw, PHY_LP_ABILITY,
+ &mii_nway_lp_ability_reg);
+ if (ret_val)
+ goto out;
+ /* Two bits in the Auto Negotiation Advertisement Register
+ * (Address 4) and two bits in the Auto Negotiation Base
+ * Page Ability Register (Address 5) determine flow control
+ * for both the PHY and the link partner. The following
+ * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
+ * 1999, describes these PAUSE resolution bits and how flow
+ * control is determined based upon these settings.
+ * NOTE: DC = Don't Care
+ *
+ * LOCAL DEVICE | LINK PARTNER
+ * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
+ *-------|---------|-------|---------|--------------------
+ * 0 | 0 | DC | DC | igc_fc_none
+ * 0 | 1 | 0 | DC | igc_fc_none
+ * 0 | 1 | 1 | 0 | igc_fc_none
+ * 0 | 1 | 1 | 1 | igc_fc_tx_pause
+ * 1 | 0 | 0 | DC | igc_fc_none
+ * 1 | DC | 1 | DC | igc_fc_full
+ * 1 | 1 | 0 | 0 | igc_fc_none
+ * 1 | 1 | 0 | 1 | igc_fc_rx_pause
+ *
+ * Are both PAUSE bits set to 1? If so, this implies
+ * Symmetric Flow Control is enabled at both ends. The
+ * ASM_DIR bits are irrelevant per the spec.
+ *
+ * For Symmetric Flow Control:
+ *
+ * LOCAL DEVICE | LINK PARTNER
+ * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
+ *-------|---------|-------|---------|--------------------
+ * 1 | DC | 1 | DC | IGC_fc_full
+ *
+ */
+ if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
+ (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE)) {
+ /* Now we need to check if the user selected RX ONLY
+ * of pause frames. In this case, we had to advertise
+ * FULL flow control because we could not advertise RX
+ * ONLY. Hence, we must now check to see if we need to
+ * turn OFF the TRANSMISSION of PAUSE frames.
*/
- else if ((hw->fc.requested_mode == igc_fc_none) ||
- (hw->fc.requested_mode == igc_fc_tx_pause) ||
- (hw->fc.strict_ieee)) {
- hw->fc.current_mode = igc_fc_none;
- hw_dbg("Flow Control = NONE.\n");
+ if (hw->fc.requested_mode == igc_fc_full) {
+ hw->fc.current_mode = igc_fc_full;
+ hw_dbg("Flow Control = FULL.\n");
} else {
hw->fc.current_mode = igc_fc_rx_pause;
hw_dbg("Flow Control = RX PAUSE frames only.\n");
}
+ }
- /* Now we need to do one last check... If we auto-
- * negotiated to HALF DUPLEX, flow control should not be
- * enabled per IEEE 802.3 spec.
- */
- ret_val = hw->mac.ops.get_speed_and_duplex(hw, &speed, &duplex);
- if (ret_val) {
- hw_dbg("Error getting link speed and duplex\n");
- goto out;
- }
+ /* For receiving PAUSE frames ONLY.
+ *
+ * LOCAL DEVICE | LINK PARTNER
+ * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
+ *-------|---------|-------|---------|--------------------
+ * 0 | 1 | 1 | 1 | igc_fc_tx_pause
+ */
+ else if (!(mii_nway_adv_reg & NWAY_AR_PAUSE) &&
+ (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
+ (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
+ (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
+ hw->fc.current_mode = igc_fc_tx_pause;
+ hw_dbg("Flow Control = TX PAUSE frames only.\n");
+ }
+ /* For transmitting PAUSE frames ONLY.
+ *
+ * LOCAL DEVICE | LINK PARTNER
+ * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
+ *-------|---------|-------|---------|--------------------
+ * 1 | 1 | 0 | 1 | igc_fc_rx_pause
+ */
+ else if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
+ (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
+ !(mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
+ (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
+ hw->fc.current_mode = igc_fc_rx_pause;
+ hw_dbg("Flow Control = RX PAUSE frames only.\n");
+ }
+ /* Per the IEEE spec, at this point flow control should be
+ * disabled. However, we want to consider that we could
+ * be connected to a legacy switch that doesn't advertise
+ * desired flow control, but can be forced on the link
+ * partner. So if we advertised no flow control, that is
+ * what we will resolve to. If we advertised some kind of
+ * receive capability (Rx Pause Only or Full Flow Control)
+ * and the link partner advertised none, we will configure
+ * ourselves to enable Rx Flow Control only. We can do
+ * this safely for two reasons: If the link partner really
+ * didn't want flow control enabled, and we enable Rx, no
+ * harm done since we won't be receiving any PAUSE frames
+ * anyway. If the intent on the link partner was to have
+ * flow control enabled, then by us enabling RX only, we
+ * can at least receive pause frames and process them.
+ * This is a good idea because in most cases, since we are
+ * predominantly a server NIC, more times than not we will
+ * be asked to delay transmission of packets than asking
+ * our link partner to pause transmission of frames.
+ */
+ else if ((hw->fc.requested_mode == igc_fc_none) ||
+ (hw->fc.requested_mode == igc_fc_tx_pause) ||
+ (hw->fc.strict_ieee)) {
+ hw->fc.current_mode = igc_fc_none;
+ hw_dbg("Flow Control = NONE.\n");
+ } else {
+ hw->fc.current_mode = igc_fc_rx_pause;
+ hw_dbg("Flow Control = RX PAUSE frames only.\n");
+ }
- if (duplex == HALF_DUPLEX)
- hw->fc.current_mode = igc_fc_none;
+ /* Now we need to do one last check... If we auto-
+ * negotiated to HALF DUPLEX, flow control should not be
+ * enabled per IEEE 802.3 spec.
+ */
+ ret_val = hw->mac.ops.get_speed_and_duplex(hw, &speed, &duplex);
+ if (ret_val) {
+ hw_dbg("Error getting link speed and duplex\n");
+ goto out;
+ }
- /* Now we call a subroutine to actually force the MAC
- * controller to use the correct flow control settings.
- */
- ret_val = igc_force_mac_fc(hw);
- if (ret_val) {
- hw_dbg("Error forcing flow control settings\n");
- goto out;
- }
+ if (duplex == HALF_DUPLEX)
+ hw->fc.current_mode = igc_fc_none;
+
+ /* Now we call a subroutine to actually force the MAC
+ * controller to use the correct flow control settings.
+ */
+ ret_val = igc_force_mac_fc(hw);
+ if (ret_val) {
+ hw_dbg("Error forcing flow control settings\n");
+ goto out;
}
out:
- return 0;
+ return ret_val;
}
/**
@@ -804,3 +765,107 @@ 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();
+}
generated by cgit (git 2.34.1) at 2025-12-24 19:09:30 +0000