From 237577e603cedc8910fc61c774b47eb1fc18eef9 Mon Sep 17 00:00:00 2001 From: Nicolai Buchwitz Date: Wed, 4 Mar 2026 11:54:28 +0100 Subject: net: cadence: macb: add EEE LPI statistics counters MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The GEM MAC provides four read-only, clear-on-read LPI statistics registers at offsets 0x270-0x27c: GEM_RXLPI (0x270): RX LPI transition count (16-bit) GEM_RXLPITIME (0x274): cumulative RX LPI time (24-bit) GEM_TXLPI (0x278): TX LPI transition count (16-bit) GEM_TXLPITIME (0x27c): cumulative TX LPI time (24-bit) Add register offset definitions, extend struct gem_stats with corresponding u64 software accumulators, and register the four counters in gem_statistics[] so they appear in ethtool -S output. Because the hardware counters clear on read, the existing macb_update_stats() path accumulates them into the u64 fields on every stats poll, preventing loss between userspace reads. These registers are present on SAMA5D2, SAME70, PIC32CZ, and RP1 variants of the Cadence GEM IP and have been confirmed on RP1 via devmem reads. Reviewed-by: Claudiu Beznea Reviewed-by: Théo Lebrun Signed-off-by: Nicolai Buchwitz Link: https://patch.msgid.link/20260304105432.631186-2-nb@tipi-net.de Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/cadence/macb.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h index 87414a2ddf6e..19aa98d01c8c 100644 --- a/drivers/net/ethernet/cadence/macb.h +++ b/drivers/net/ethernet/cadence/macb.h @@ -170,6 +170,10 @@ #define GEM_PCSANNPTX 0x021c /* PCS AN Next Page TX */ #define GEM_PCSANNPLP 0x0220 /* PCS AN Next Page LP */ #define GEM_PCSANEXTSTS 0x023c /* PCS AN Extended Status */ +#define GEM_RXLPI 0x0270 /* RX LPI Transitions */ +#define GEM_RXLPITIME 0x0274 /* RX LPI Time */ +#define GEM_TXLPI 0x0278 /* TX LPI Transitions */ +#define GEM_TXLPITIME 0x027c /* TX LPI Time */ #define GEM_DCFG1 0x0280 /* Design Config 1 */ #define GEM_DCFG2 0x0284 /* Design Config 2 */ #define GEM_DCFG3 0x0288 /* Design Config 3 */ @@ -1043,6 +1047,10 @@ struct gem_stats { u64 rx_ip_header_checksum_errors; u64 rx_tcp_checksum_errors; u64 rx_udp_checksum_errors; + u64 rx_lpi_transitions; + u64 rx_lpi_time; + u64 tx_lpi_transitions; + u64 tx_lpi_time; }; /* Describes the name and offset of an individual statistic register, as @@ -1142,6 +1150,10 @@ static const struct gem_statistic gem_statistics[] = { GEM_BIT(NDS_RXERR)), GEM_STAT_TITLE_BITS(RXUDPCCNT, "rx_udp_checksum_errors", GEM_BIT(NDS_RXERR)), + GEM_STAT_TITLE(RXLPI, "rx_lpi_transitions"), + GEM_STAT_TITLE(RXLPITIME, "rx_lpi_time"), + GEM_STAT_TITLE(TXLPI, "tx_lpi_transitions"), + GEM_STAT_TITLE(TXLPITIME, "tx_lpi_time"), }; #define GEM_STATS_LEN ARRAY_SIZE(gem_statistics) -- cgit v1.2.3 From 0cc425f18f59f992c61c1802331d25ce689ff5d1 Mon Sep 17 00:00:00 2001 From: Nicolai Buchwitz Date: Wed, 4 Mar 2026 11:54:29 +0100 Subject: net: cadence: macb: implement EEE TX LPI support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The GEM MAC has hardware LPI registers (NCR bit 19: TXLPIEN) but no built-in idle timer, so asserting TXLPIEN blocks all TX immediately with no automatic wake. A software idle timer is required, as noted in Microchip documentation (section 40.6.19): "It is best to use firmware to control LPI." Implement phylink managed EEE using the mac_enable_tx_lpi and mac_disable_tx_lpi callbacks: - macb_tx_lpi_set(): sets or clears TXLPIEN; requires bp->lock to be held by the caller (asserted with lockdep_assert_held). Returns bool indicating whether the register actually changed, avoiding redundant writes and unnecessary udelay on the xmit fast path. - macb_tx_lpi_work_fn(): delayed_work handler that enters LPI if all TX queues are idle and EEE is still active. Takes bp->lock with irqsave before calling macb_tx_lpi_set(). - macb_tx_lpi_schedule(): arms the work timer using the LPI timer value provided by phylink (default 250 ms). Called from macb_tx_complete() after each TX drain so the idle countdown restarts whenever the ring goes quiet. - macb_tx_lpi_wake(): called from macb_start_xmit() under bp->lock, immediately before TSTART. Returns early if eee_active is false to avoid a register read on the common path when EEE is disabled. Clears TXLPIEN and applies a 50 us udelay for PHY wake (IEEE 802.3az Tw_sys_tx is 16.5 us for 1000BASE-T / 30 us for 100BASE-TX; GEM has no hardware enforcement). Only delays when TXLPIEN was actually set. The delay is placed after tx_head is advanced so the work_fn's queue-idle check sees a non-empty ring and cannot race back into LPI before the frame is transmitted. - mac_enable_tx_lpi: stores the timer and sets eee_active under bp->lock, then defers the first LPI entry by 1 second per IEEE 802.3az section 22.7a. - mac_disable_tx_lpi: cancels the work (sync, without the lock to avoid deadlock with the work_fn), then takes bp->lock to clear eee_active and deassert TXLPIEN. Populate phylink_config lpi_interfaces (MII, GMII, RGMII variants) and lpi_capabilities (MAC_100FD | MAC_1000FD) so phylink can negotiate EEE with the PHY and call the callbacks appropriately. Set lpi_timer_default to 250000 us and eee_enabled_default to true. Reviewed-by: Claudiu Beznea Reviewed-by: Théo Lebrun Signed-off-by: Nicolai Buchwitz Link: https://patch.msgid.link/20260304105432.631186-3-nb@tipi-net.de Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/cadence/macb.h | 8 ++ drivers/net/ethernet/cadence/macb_main.c | 124 +++++++++++++++++++++++++++++++ 2 files changed, 132 insertions(+) diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h index 19aa98d01c8c..c69828b27dae 100644 --- a/drivers/net/ethernet/cadence/macb.h +++ b/drivers/net/ethernet/cadence/macb.h @@ -309,6 +309,8 @@ #define MACB_IRXFCS_SIZE 1 /* GEM specific NCR bitfields. */ +#define GEM_TXLPIEN_OFFSET 19 +#define GEM_TXLPIEN_SIZE 1 #define GEM_ENABLE_HS_MAC_OFFSET 31 #define GEM_ENABLE_HS_MAC_SIZE 1 @@ -783,6 +785,7 @@ #define MACB_CAPS_DMA_PTP BIT(22) #define MACB_CAPS_RSC BIT(23) #define MACB_CAPS_NO_LSO BIT(24) +#define MACB_CAPS_EEE BIT(25) /* LSO settings */ #define MACB_LSO_UFO_ENABLE 0x01 @@ -1369,6 +1372,11 @@ struct macb { struct work_struct hresp_err_bh_work; + /* EEE / LPI state */ + bool eee_active; + struct delayed_work tx_lpi_work; + u32 tx_lpi_timer; + int rx_bd_rd_prefetch; int tx_bd_rd_prefetch; diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 17f0ad3d7a09..4e776c67f408 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -621,6 +622,107 @@ static const struct phylink_pcs_ops macb_phylink_pcs_ops = { .pcs_config = macb_pcs_config, }; +static bool macb_tx_lpi_set(struct macb *bp, bool enable) +{ + u32 old, ncr; + + lockdep_assert_held(&bp->lock); + + ncr = macb_readl(bp, NCR); + old = ncr; + if (enable) + ncr |= GEM_BIT(TXLPIEN); + else + ncr &= ~GEM_BIT(TXLPIEN); + if (old != ncr) + macb_writel(bp, NCR, ncr); + + return old != ncr; +} + +static bool macb_tx_all_queues_idle(struct macb *bp) +{ + struct macb_queue *queue; + unsigned int q; + + for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) { + if (READ_ONCE(queue->tx_head) != READ_ONCE(queue->tx_tail)) + return false; + } + return true; +} + +static void macb_tx_lpi_work_fn(struct work_struct *work) +{ + struct macb *bp = container_of(work, struct macb, tx_lpi_work.work); + unsigned long flags; + + spin_lock_irqsave(&bp->lock, flags); + if (bp->eee_active && macb_tx_all_queues_idle(bp)) + macb_tx_lpi_set(bp, true); + spin_unlock_irqrestore(&bp->lock, flags); +} + +static void macb_tx_lpi_schedule(struct macb *bp) +{ + if (bp->eee_active) + mod_delayed_work(system_wq, &bp->tx_lpi_work, + usecs_to_jiffies(bp->tx_lpi_timer)); +} + +/* Wake from LPI before transmitting. The MAC must deassert TXLPIEN + * and wait for the PHY to exit LPI before any frame can be sent. + * IEEE 802.3az Tw_sys is ~17us for 1000BASE-T, ~30us for 100BASE-TX; + * we use a conservative 50us. + */ +static void macb_tx_lpi_wake(struct macb *bp) +{ + lockdep_assert_held(&bp->lock); + + if (!bp->eee_active) + return; + + if (!macb_tx_lpi_set(bp, false)) + return; + + cancel_delayed_work(&bp->tx_lpi_work); + udelay(50); +} + +static void macb_mac_disable_tx_lpi(struct phylink_config *config) +{ + struct net_device *ndev = to_net_dev(config->dev); + struct macb *bp = netdev_priv(ndev); + unsigned long flags; + + cancel_delayed_work_sync(&bp->tx_lpi_work); + + spin_lock_irqsave(&bp->lock, flags); + bp->eee_active = false; + macb_tx_lpi_set(bp, false); + spin_unlock_irqrestore(&bp->lock, flags); +} + +static int macb_mac_enable_tx_lpi(struct phylink_config *config, u32 timer, + bool tx_clk_stop) +{ + struct net_device *ndev = to_net_dev(config->dev); + struct macb *bp = netdev_priv(ndev); + unsigned long flags; + + spin_lock_irqsave(&bp->lock, flags); + bp->tx_lpi_timer = timer; + bp->eee_active = true; + spin_unlock_irqrestore(&bp->lock, flags); + + /* Defer initial LPI entry by 1 second after link-up per + * IEEE 802.3az section 22.7a. + */ + mod_delayed_work(system_wq, &bp->tx_lpi_work, msecs_to_jiffies(1000)); + + return 0; +} + static void macb_mac_config(struct phylink_config *config, unsigned int mode, const struct phylink_link_state *state) { @@ -769,6 +871,8 @@ static const struct phylink_mac_ops macb_phylink_ops = { .mac_config = macb_mac_config, .mac_link_down = macb_mac_link_down, .mac_link_up = macb_mac_link_up, + .mac_disable_tx_lpi = macb_mac_disable_tx_lpi, + .mac_enable_tx_lpi = macb_mac_enable_tx_lpi, }; static bool macb_phy_handle_exists(struct device_node *dn) @@ -864,6 +968,18 @@ static int macb_mii_probe(struct net_device *dev) } } + /* Configure EEE LPI if supported */ + if (bp->caps & MACB_CAPS_EEE) { + __set_bit(PHY_INTERFACE_MODE_MII, + bp->phylink_config.lpi_interfaces); + __set_bit(PHY_INTERFACE_MODE_GMII, + bp->phylink_config.lpi_interfaces); + phy_interface_set_rgmii(bp->phylink_config.lpi_interfaces); + bp->phylink_config.lpi_capabilities = MAC_100FD | MAC_1000FD; + bp->phylink_config.lpi_timer_default = 250000; + bp->phylink_config.eee_enabled_default = true; + } + bp->phylink = phylink_create(&bp->phylink_config, bp->pdev->dev.fwnode, bp->phy_interface, &macb_phylink_ops); if (IS_ERR(bp->phylink)) { @@ -1260,6 +1376,9 @@ static int macb_tx_complete(struct macb_queue *queue, int budget) netif_wake_subqueue(bp->dev, queue_index); spin_unlock_irqrestore(&queue->tx_ptr_lock, flags); + if (packets) + macb_tx_lpi_schedule(bp); + return packets; } @@ -2366,6 +2485,7 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev) skb->len); spin_lock(&bp->lock); + macb_tx_lpi_wake(bp); macb_writel(bp, NCR, macb_readl(bp, NCR) | MACB_BIT(TSTART)); spin_unlock(&bp->lock); @@ -3026,6 +3146,8 @@ static int macb_close(struct net_device *dev) netdev_tx_reset_queue(netdev_get_tx_queue(dev, q)); } + cancel_delayed_work_sync(&bp->tx_lpi_work); + phylink_stop(bp->phylink); phylink_disconnect_phy(bp->phylink); @@ -5629,6 +5751,7 @@ static int macb_probe(struct platform_device *pdev) } INIT_WORK(&bp->hresp_err_bh_work, macb_hresp_error_task); + INIT_DELAYED_WORK(&bp->tx_lpi_work, macb_tx_lpi_work_fn); netdev_info(dev, "Cadence %s rev 0x%08x at 0x%08lx irq %d (%pM)\n", macb_is_gem(bp) ? "GEM" : "MACB", macb_readl(bp, MID), @@ -5672,6 +5795,7 @@ static void macb_remove(struct platform_device *pdev) mdiobus_free(bp->mii_bus); device_set_wakeup_enable(&bp->pdev->dev, 0); + cancel_delayed_work_sync(&bp->tx_lpi_work); cancel_work_sync(&bp->hresp_err_bh_work); pm_runtime_disable(&pdev->dev); pm_runtime_dont_use_autosuspend(&pdev->dev); -- cgit v1.2.3 From 61332b78761cb1638e2bf29273050cf009fbbc0e Mon Sep 17 00:00:00 2001 From: Nicolai Buchwitz Date: Wed, 4 Mar 2026 11:54:30 +0100 Subject: net: cadence: macb: add ethtool EEE support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Implement get_eee and set_eee ethtool ops for GEM as simple passthroughs to phylink_ethtool_get_eee() and phylink_ethtool_set_eee(). No MACB_CAPS_EEE guard is needed: phylink returns -EOPNOTSUPP from both ops when mac_supports_eee is false, which is the case when lpi_capabilities and lpi_interfaces are not populated. Those fields are only set when MACB_CAPS_EEE is present (previous patch), so phylink already handles the unsupported case correctly. Reviewed-by: Claudiu Beznea Reviewed-by: Théo Lebrun Signed-off-by: Nicolai Buchwitz Link: https://patch.msgid.link/20260304105432.631186-4-nb@tipi-net.de Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/cadence/macb_main.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 4e776c67f408..f01366394cff 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -4058,6 +4058,20 @@ static const struct ethtool_ops macb_ethtool_ops = { .set_ringparam = macb_set_ringparam, }; +static int macb_get_eee(struct net_device *dev, struct ethtool_keee *eee) +{ + struct macb *bp = netdev_priv(dev); + + return phylink_ethtool_get_eee(bp->phylink, eee); +} + +static int macb_set_eee(struct net_device *dev, struct ethtool_keee *eee) +{ + struct macb *bp = netdev_priv(dev); + + return phylink_ethtool_set_eee(bp->phylink, eee); +} + static const struct ethtool_ops gem_ethtool_ops = { .get_regs_len = macb_get_regs_len, .get_regs = macb_get_regs, @@ -4080,6 +4094,8 @@ static const struct ethtool_ops gem_ethtool_ops = { .set_rxnfc = gem_set_rxnfc, .get_rx_ring_count = gem_get_rx_ring_count, .nway_reset = phy_ethtool_nway_reset, + .get_eee = macb_get_eee, + .set_eee = macb_set_eee, }; static int macb_ioctl(struct net_device *dev, struct ifreq *rq, int cmd) -- cgit v1.2.3 From 92ba3307431a1756a3c8094787527a38ce19623d Mon Sep 17 00:00:00 2001 From: Nicolai Buchwitz Date: Wed, 4 Mar 2026 11:54:31 +0100 Subject: net: cadence: macb: enable EEE for Raspberry Pi RP1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Set MACB_CAPS_EEE for the Raspberry Pi 5 RP1 southbridge (Cadence GEM_GXL rev 0x00070109 paired with BCM54213PE PHY). EEE has been verified on RP1 hardware: the LPI counter registers at 0x270-0x27c return valid data, the TXLPIEN bit in NCR (bit 19) controls LPI transmission correctly, and ethtool --show-eee reports the negotiated state after link-up. Other GEM variants that share the same LPI register layout (SAMA5D2, SAME70, PIC32CZ) can be enabled by adding MACB_CAPS_EEE to their respective config entries once tested. Reviewed-by: Claudiu Beznea Reviewed-by: Théo Lebrun Signed-off-by: Nicolai Buchwitz Link: https://patch.msgid.link/20260304105432.631186-5-nb@tipi-net.de Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/cadence/macb_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index f01366394cff..5933a5042bc8 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -5537,7 +5537,8 @@ static const struct macb_config eyeq5_config = { static const struct macb_config raspberrypi_rp1_config = { .caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_CLK_HW_CHG | MACB_CAPS_JUMBO | - MACB_CAPS_GEM_HAS_PTP, + MACB_CAPS_GEM_HAS_PTP | + MACB_CAPS_EEE, .dma_burst_length = 16, .clk_init = macb_clk_init, .init = macb_init, -- cgit v1.2.3 From 48575b6e16d12365d6a69de13d061d9df2b775ec Mon Sep 17 00:00:00 2001 From: Nicolai Buchwitz Date: Wed, 4 Mar 2026 11:54:32 +0100 Subject: net: cadence: macb: enable EEE for Mobileye EyeQ5 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Set MACB_CAPS_EEE for the Mobileye EyeQ5 GEM instance. EEE has been verified on EyeQ5 hardware using a loopback setup with ethtool --show-eee confirming EEE active on both ends at 100baseT/Full and 1000baseT/Full. Tested-by: Théo Lebrun Signed-off-by: Nicolai Buchwitz Link: https://patch.msgid.link/20260304105432.631186-6-nb@tipi-net.de Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/cadence/macb_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 5933a5042bc8..3dcae4d5f74c 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -5526,7 +5526,7 @@ static const struct macb_config versal_config = { static const struct macb_config eyeq5_config = { .caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_JUMBO | MACB_CAPS_GEM_HAS_PTP | MACB_CAPS_QUEUE_DISABLE | - MACB_CAPS_NO_LSO, + MACB_CAPS_NO_LSO | MACB_CAPS_EEE, .dma_burst_length = 16, .clk_init = macb_clk_init, .init = eyeq5_init, -- cgit v1.2.3