net: stmmac: fix LPI transitioning for dwmac4

The LPI transitioning logic in stmmac_main uses
priv->tx_path_in_lpi_mode to enter/exit LPI.

However, priv->tx_path_in_lpi_mode is assigned
using the return value from host_irq_status().

So for dwmac4, priv->tx_path_in_lpi_mode was always false,
so stmmac_tx_clean() would always try to put us in eee mode,
and stmmac_xmit() would never take us out of eee mode.

To fix this, make host_irq_status() read and return the LPI
irq status also for dwmac4.

This also increments the existing LPI counters, so that
ethtool --statistics shows LPI transitions also for dwmac4.

For dwmac1000, irqs are enabled/disabled using the register
named "Interrupt Mask Register", and thus setting a bit disables
that specific irq.

For dwmac4 the matching register is named "MAC_Interrupt_Enable",
and thus setting a bit enables that specific irq.

Looking at dwmac1000_core.c, the irqs that are always enabled are:
LPI and PMT.

Looking at dwmac4_core.c, the irqs that are always enabled are:
PMT.

To be able to read the LPI irq status, we need to enable the LPI
irq also for dwmac4.

Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
index aeda3ab2d761c3e689b2661fa6118b61e271098f..789dad8a07b5ccfa1f2cd03993ef67eb21a720a3 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h
@@ -98,7 +98,7 @@
 #define        GMAC_PCS_IRQ_DEFAULT    (GMAC_INT_RGSMIIS | GMAC_INT_PCS_LINK | \
                                 GMAC_INT_PCS_ANE)
 
-#define        GMAC_INT_DEFAULT_MASK   GMAC_INT_PMT_EN
+#define        GMAC_INT_DEFAULT_MASK   (GMAC_INT_PMT_EN | GMAC_INT_LPI_EN)
 
 enum dwmac4_irq_status {
        time_stamp_irq = 0x00001000,
@@ -106,6 +106,7 @@ enum dwmac4_irq_status {
        mmc_tx_irq = 0x00000400,
        mmc_rx_irq = 0x00000200,
        mmc_irq = 0x00000100,
+       lpi_irq = 0x00000020,
        pmt_irq = 0x00000010,
 };
 
@@ -132,6 +133,10 @@ enum power_event {
 #define GMAC4_LPI_CTRL_STATUS_LPITXA   BIT(19) /* Enable LPI TX Automate */
 #define GMAC4_LPI_CTRL_STATUS_PLS      BIT(17) /* PHY Link Status */
 #define GMAC4_LPI_CTRL_STATUS_LPIEN    BIT(16) /* LPI Enable */
+#define GMAC4_LPI_CTRL_STATUS_RLPIEX   BIT(3) /* Receive LPI Exit */
+#define GMAC4_LPI_CTRL_STATUS_RLPIEN   BIT(2) /* Receive LPI Entry */
+#define GMAC4_LPI_CTRL_STATUS_TLPIEX   BIT(1) /* Transmit LPI Exit */
+#define GMAC4_LPI_CTRL_STATUS_TLPIEN   BIT(0) /* Transmit LPI Entry */
 
 /* MAC Debug bitmap */
 #define GMAC_DEBUG_TFCSTS_MASK         GENMASK(18, 17)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index 2f7d7ec59962a7050a278d53e2241024566bb66d..f3ed8f7853eb4f0908718dd03eca2f9dc7dad350 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -580,6 +580,25 @@ static int dwmac4_irq_status(struct mac_device_info *hw,
                x->irq_receive_pmt_irq_n++;
        }
 
+       /* MAC tx/rx EEE LPI entry/exit interrupts */
+       if (intr_status & lpi_irq) {
+               /* Clear LPI interrupt by reading MAC_LPI_Control_Status */
+               u32 status = readl(ioaddr + GMAC4_LPI_CTRL_STATUS);
+
+               if (status & GMAC4_LPI_CTRL_STATUS_TLPIEN) {
+                       ret |= CORE_IRQ_TX_PATH_IN_LPI_MODE;
+                       x->irq_tx_path_in_lpi_mode_n++;
+               }
+               if (status & GMAC4_LPI_CTRL_STATUS_TLPIEX) {
+                       ret |= CORE_IRQ_TX_PATH_EXIT_LPI_MODE;
+                       x->irq_tx_path_exit_lpi_mode_n++;
+               }
+               if (status & GMAC4_LPI_CTRL_STATUS_RLPIEN)
+                       x->irq_rx_path_in_lpi_mode_n++;
+               if (status & GMAC4_LPI_CTRL_STATUS_RLPIEX)
+                       x->irq_rx_path_exit_lpi_mode_n++;
+       }
+
        dwmac_pcs_isr(ioaddr, GMAC_PCS_BASE, intr_status, x);
        if (intr_status & PCS_RGSMIIIS_IRQ)
                dwmac4_phystatus(ioaddr, x);