From 1cbf19c575ddbec27eec99396329810b1a5f7976 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:23 +0200 Subject: [PATCH 01/12] net: enetc: set next_to_clean/next_to_use just from enetc_setup_txbdr() enetc_alloc_txbdr() deals with allocating resources necessary for a TX ring to work (the array of software BDs and the array of TSO headers). The next_to_clean and next_to_use pointers are overwritten with proper values which are read from hardware here: enetc_open -> enetc_alloc_tx_resources -> enetc_alloc_txbdr -> set to zero -> enetc_setup_bdrs -> enetc_setup_txbdr -> read from hardware So their initialization with zeroes is pointless and confusing. Delete it. Consequently, since enetc_setup_txbdr() has no opposite cleanup function, also delete the resetting of these indices from enetc_free_tx_ring(). Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 5ad0b259e6235..911686df16e4e 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1753,9 +1753,6 @@ static int enetc_alloc_txbdr(struct enetc_bdr *txr) goto err_alloc_tso; } - txr->next_to_clean = 0; - txr->next_to_use = 0; - return 0; err_alloc_tso: @@ -1897,9 +1894,6 @@ static void enetc_free_tx_ring(struct enetc_bdr *tx_ring) enetc_free_tx_frame(tx_ring, tx_swbd); } - - tx_ring->next_to_clean = 0; - tx_ring->next_to_use = 0; } static void enetc_free_rx_ring(struct enetc_bdr *rx_ring) From fbf1cff98c9591bd60deb56e3ea5aa0efdc15843 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:24 +0200 Subject: [PATCH 02/12] net: enetc: set up RX ring indices from enetc_setup_rxbdr() There is only one place which needs to set up indices in the RX ring. Be consistent with what was done in the TX path and do this in enetc_setup_rxbdr(). Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 911686df16e4e..4f8c94957a8e2 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1832,9 +1832,6 @@ static int enetc_alloc_rxbdr(struct enetc_bdr *rxr, bool extended) return err; } - rxr->next_to_clean = 0; - rxr->next_to_use = 0; - rxr->next_to_alloc = 0; rxr->ext_en = extended; return 0; @@ -1914,10 +1911,6 @@ static void enetc_free_rx_ring(struct enetc_bdr *rx_ring) __free_page(rx_swbd->page); rx_swbd->page = NULL; } - - rx_ring->next_to_clean = 0; - rx_ring->next_to_use = 0; - rx_ring->next_to_alloc = 0; } static void enetc_free_rxtx_rings(struct enetc_ndev_priv *priv) @@ -2084,6 +2077,10 @@ static void enetc_setup_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) rx_ring->rcir = hw->reg + ENETC_BDR(RX, idx, ENETC_RBCIR); rx_ring->idr = hw->reg + ENETC_SIRXIDR; + rx_ring->next_to_clean = 0; + rx_ring->next_to_use = 0; + rx_ring->next_to_alloc = 0; + enetc_lock_mdio(); enetc_refill_rx_ring(rx_ring, enetc_bd_unused(rx_ring)); enetc_unlock_mdio(); From 0d6cfd0f5e4d7a2f7254f62a16bec30cd92b6d5d Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:25 +0200 Subject: [PATCH 03/12] net: enetc: create enetc_dma_free_bdr() This is a refactoring change which introduces the opposite function of enetc_dma_alloc_bdr(). Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 25 +++++++++----------- 1 file changed, 11 insertions(+), 14 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 4f8c94957a8e2..ca1dacccf9fe6 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1732,6 +1732,13 @@ static int enetc_dma_alloc_bdr(struct enetc_bdr *r, size_t bd_size) return 0; } +static void enetc_dma_free_bdr(struct enetc_bdr *r, size_t bd_size) +{ + dma_free_coherent(r->dev, r->bd_count * bd_size, r->bd_base, + r->bd_dma_base); + r->bd_base = NULL; +} + static int enetc_alloc_txbdr(struct enetc_bdr *txr) { int err; @@ -1756,9 +1763,7 @@ static int enetc_alloc_txbdr(struct enetc_bdr *txr) return 0; err_alloc_tso: - dma_free_coherent(txr->dev, txr->bd_count * sizeof(union enetc_tx_bd), - txr->bd_base, txr->bd_dma_base); - txr->bd_base = NULL; + enetc_dma_free_bdr(txr, sizeof(union enetc_tx_bd)); err_alloc_bdr: vfree(txr->tx_swbd); txr->tx_swbd = NULL; @@ -1768,19 +1773,16 @@ static int enetc_alloc_txbdr(struct enetc_bdr *txr) static void enetc_free_txbdr(struct enetc_bdr *txr) { - int size, i; + int i; for (i = 0; i < txr->bd_count; i++) enetc_free_tx_frame(txr, &txr->tx_swbd[i]); - size = txr->bd_count * sizeof(union enetc_tx_bd); - dma_free_coherent(txr->dev, txr->bd_count * TSO_HEADER_SIZE, txr->tso_headers, txr->tso_headers_dma); txr->tso_headers = NULL; - dma_free_coherent(txr->dev, size, txr->bd_base, txr->bd_dma_base); - txr->bd_base = NULL; + enetc_dma_free_bdr(txr, sizeof(union enetc_tx_bd)); vfree(txr->tx_swbd); txr->tx_swbd = NULL; @@ -1839,12 +1841,7 @@ static int enetc_alloc_rxbdr(struct enetc_bdr *rxr, bool extended) static void enetc_free_rxbdr(struct enetc_bdr *rxr) { - int size; - - size = rxr->bd_count * sizeof(union enetc_rx_bd); - - dma_free_coherent(rxr->dev, size, rxr->bd_base, rxr->bd_dma_base); - rxr->bd_base = NULL; + enetc_dma_free_bdr(rxr, sizeof(union enetc_rx_bd)); vfree(rxr->rx_swbd); rxr->rx_swbd = NULL; From 2c3387109d11690dd7dd91c9c8e497f918f988da Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:26 +0200 Subject: [PATCH 04/12] net: enetc: rx_swbd and tx_swbd are never NULL in enetc_free_rxtx_rings() The call path in enetc_close() is: enetc_close() -> enetc_free_rxtx_rings() -> enetc_free_rx_ring() -> tests whether rx_ring->rx_swbd is NULL -> enetc_free_tx_ring() -> tests whether tx_ring->tx_swbd is NULL -> enetc_free_rx_resources() -> enetc_free_rxbdr() -> sets rxr->rx_swbd to NULL -> enetc_free_tx_resources() -> enetc_free_txbdr() -> setx txr->tx_swbd to NULL From the above, it is clear that due to the function ordering, the checks for NULL are redundant, since the software buffer descriptor arrays have not yet been set to NULL. Drop these checks. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index ca1dacccf9fe6..f41a02c2213ee 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1880,9 +1880,6 @@ static void enetc_free_tx_ring(struct enetc_bdr *tx_ring) { int i; - if (!tx_ring->tx_swbd) - return; - for (i = 0; i < tx_ring->bd_count; i++) { struct enetc_tx_swbd *tx_swbd = &tx_ring->tx_swbd[i]; @@ -1894,9 +1891,6 @@ static void enetc_free_rx_ring(struct enetc_bdr *rx_ring) { int i; - if (!rx_ring->rx_swbd) - return; - for (i = 0; i < rx_ring->bd_count; i++) { struct enetc_rx_swbd *rx_swbd = &rx_ring->rx_swbd[i]; From bbd6043f74e139a58052b34df3a4b87da7df00bb Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:27 +0200 Subject: [PATCH 05/12] net: enetc: drop redundant enetc_free_tx_frame() call from enetc_free_txbdr() The call path in enetc_close() is: enetc_close() -> enetc_free_rxtx_rings() -> enetc_free_tx_ring() -> enetc_free_tx_frame() -> enetc_free_tx_resources() -> enetc_free_txbdr() -> enetc_free_tx_frame() The enetc_free_tx_frame() function is written such that the second call exits without doing anything, but nonetheless, it is completely redundant. Delete it. This makes the TX teardown path more similar to the RX one, where rx_swbd freeing is done in enetc_free_rx_ring(), not in enetc_free_rxbdr(). Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index f41a02c2213ee..94580496ef64d 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1773,11 +1773,6 @@ static int enetc_alloc_txbdr(struct enetc_bdr *txr) static void enetc_free_txbdr(struct enetc_bdr *txr) { - int i; - - for (i = 0; i < txr->bd_count; i++) - enetc_free_tx_frame(txr, &txr->tx_swbd[i]); - dma_free_coherent(txr->dev, txr->bd_count * TSO_HEADER_SIZE, txr->tso_headers, txr->tso_headers_dma); txr->tso_headers = NULL; From d075db51e013a7a6bea189c7f6824f458b621626 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:28 +0200 Subject: [PATCH 06/12] net: enetc: bring "bool extended" to top-level in enetc_open() Extended RX buffer descriptors are necessary if they carry RX timestamps, which will be true when PTP timestamping is enabled. Right now, the rx_ring->ext_en is set from the function that allocates ring resources (enetc_alloc_rx_resources() -> enetc_alloc_rxbdr()), and also used later, in enetc_setup_rxbdr(). It is also used in the enetc_rxbd() and enetc_rxbd_next() fast path helpers. We want to decouple resource allocation from BD ring setup, but both procedures depend on BD size (extended or not). Move the "extended" boolean to enetc_open() and pass it both to the RX allocation procedure as well as to the RX ring setup procedure. The latter will set rx_ring->ext_en from now on. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 94580496ef64d..67471c8ea447a 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1829,8 +1829,6 @@ static int enetc_alloc_rxbdr(struct enetc_bdr *rxr, bool extended) return err; } - rxr->ext_en = extended; - return 0; } @@ -1842,9 +1840,8 @@ static void enetc_free_rxbdr(struct enetc_bdr *rxr) rxr->rx_swbd = NULL; } -static int enetc_alloc_rx_resources(struct enetc_ndev_priv *priv) +static int enetc_alloc_rx_resources(struct enetc_ndev_priv *priv, bool extended) { - bool extended = !!(priv->active_offloads & ENETC_F_RX_TSTAMP); int i, err; for (i = 0; i < priv->num_rx_rings; i++) { @@ -2022,7 +2019,8 @@ static void enetc_setup_txbdr(struct enetc_hw *hw, struct enetc_bdr *tx_ring) tx_ring->idr = hw->reg + ENETC_SITXIDR; } -static void enetc_setup_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) +static void enetc_setup_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring, + bool extended) { int idx = rx_ring->index; u32 rbmr; @@ -2054,6 +2052,7 @@ static void enetc_setup_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) rbmr = ENETC_RBMR_EN; + rx_ring->ext_en = extended; if (rx_ring->ext_en) rbmr |= ENETC_RBMR_BDS; @@ -2075,7 +2074,7 @@ static void enetc_setup_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) enetc_rxbdr_wr(hw, idx, ENETC_RBMR, rbmr); } -static void enetc_setup_bdrs(struct enetc_ndev_priv *priv) +static void enetc_setup_bdrs(struct enetc_ndev_priv *priv, bool extended) { struct enetc_hw *hw = &priv->si->hw; int i; @@ -2084,7 +2083,7 @@ static void enetc_setup_bdrs(struct enetc_ndev_priv *priv) enetc_setup_txbdr(hw, priv->tx_ring[i]); for (i = 0; i < priv->num_rx_rings; i++) - enetc_setup_rxbdr(hw, priv->rx_ring[i]); + enetc_setup_rxbdr(hw, priv->rx_ring[i], extended); } static void enetc_clear_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) @@ -2308,8 +2307,11 @@ int enetc_open(struct net_device *ndev) { struct enetc_ndev_priv *priv = netdev_priv(ndev); int num_stack_tx_queues; + bool extended; int err; + extended = !!(priv->active_offloads & ENETC_F_RX_TSTAMP); + err = enetc_setup_irqs(priv); if (err) return err; @@ -2322,7 +2324,7 @@ int enetc_open(struct net_device *ndev) if (err) goto err_alloc_tx; - err = enetc_alloc_rx_resources(priv); + err = enetc_alloc_rx_resources(priv, extended); if (err) goto err_alloc_rx; @@ -2337,7 +2339,7 @@ int enetc_open(struct net_device *ndev) goto err_set_queues; enetc_tx_onestep_tstamp_init(priv); - enetc_setup_bdrs(priv); + enetc_setup_bdrs(priv, extended); enetc_start(ndev); return 0; From f3ce29e169d0b88dcb4909265eff517587f21be1 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:29 +0200 Subject: [PATCH 07/12] net: enetc: split ring resource allocation from assignment We have a few instances in the enetc driver where the ring resources (BD ring iomem, software BD ring, software TSO headers, basically everything except RX buffers) need to be reallocated. For example, when RX timestamping is enabled, the RX BD format changes to an extended one (twice as large). Currently, this is done using a simplistic enetc_close() -> enetc_open() procedure. But this is quite crude, since it also invokes phylink_stop() -> phylink_start(), the link is lost, and a few seconds need to pass for autoneg to complete again. In fact it's bad also due to the improper (yolo) error checking. In case we fail to allocate new resources, we've already freed the old ones, so the interface is more or less stuck. To avoid that, we need a system where reconfiguration is possible in a way in which resources are allocated upfront. This means that there will be a higher memory usage temporarily, but the assignment of resources to rings can be done when both the old and new resources are still available. Introduce a struct enetc_bdr_resource which holds the resources for a ring, be it RX or TX. This structure duplicates a lot of fields from struct enetc_bdr (and access to the same fields in the ring structure was left duplicated, to not change cache characteristics in the fast path). When enetc_alloc_tx_resources() runs, it returns an array of resource elements (one per TX ring), in addition to the existing priv->tx_res. To populate priv->tx_res with that array, one must call enetc_assign_tx_resources(), and this also frees the old resources. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 231 +++++++++++++------ drivers/net/ethernet/freescale/enetc/enetc.h | 19 ++ 2 files changed, 180 insertions(+), 70 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 67471c8ea447a..543ae8875bc9f 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -1715,47 +1715,54 @@ void enetc_get_si_caps(struct enetc_si *si) si->hw_features |= ENETC_SI_F_PSFP; } -static int enetc_dma_alloc_bdr(struct enetc_bdr *r, size_t bd_size) +static int enetc_dma_alloc_bdr(struct enetc_bdr_resource *res) { - r->bd_base = dma_alloc_coherent(r->dev, r->bd_count * bd_size, - &r->bd_dma_base, GFP_KERNEL); - if (!r->bd_base) + size_t bd_base_size = res->bd_count * res->bd_size; + + res->bd_base = dma_alloc_coherent(res->dev, bd_base_size, + &res->bd_dma_base, GFP_KERNEL); + if (!res->bd_base) return -ENOMEM; /* h/w requires 128B alignment */ - if (!IS_ALIGNED(r->bd_dma_base, 128)) { - dma_free_coherent(r->dev, r->bd_count * bd_size, r->bd_base, - r->bd_dma_base); + if (!IS_ALIGNED(res->bd_dma_base, 128)) { + dma_free_coherent(res->dev, bd_base_size, res->bd_base, + res->bd_dma_base); return -EINVAL; } return 0; } -static void enetc_dma_free_bdr(struct enetc_bdr *r, size_t bd_size) +static void enetc_dma_free_bdr(const struct enetc_bdr_resource *res) { - dma_free_coherent(r->dev, r->bd_count * bd_size, r->bd_base, - r->bd_dma_base); - r->bd_base = NULL; + size_t bd_base_size = res->bd_count * res->bd_size; + + dma_free_coherent(res->dev, bd_base_size, res->bd_base, + res->bd_dma_base); } -static int enetc_alloc_txbdr(struct enetc_bdr *txr) +static int enetc_alloc_tx_resource(struct enetc_bdr_resource *res, + struct device *dev, size_t bd_count) { int err; - txr->tx_swbd = vzalloc(txr->bd_count * sizeof(struct enetc_tx_swbd)); - if (!txr->tx_swbd) + res->dev = dev; + res->bd_count = bd_count; + res->bd_size = sizeof(union enetc_tx_bd); + + res->tx_swbd = vzalloc(bd_count * sizeof(*res->tx_swbd)); + if (!res->tx_swbd) return -ENOMEM; - err = enetc_dma_alloc_bdr(txr, sizeof(union enetc_tx_bd)); + err = enetc_dma_alloc_bdr(res); if (err) goto err_alloc_bdr; - txr->tso_headers = dma_alloc_coherent(txr->dev, - txr->bd_count * TSO_HEADER_SIZE, - &txr->tso_headers_dma, + res->tso_headers = dma_alloc_coherent(dev, bd_count * TSO_HEADER_SIZE, + &res->tso_headers_dma, GFP_KERNEL); - if (!txr->tso_headers) { + if (!res->tso_headers) { err = -ENOMEM; goto err_alloc_tso; } @@ -1763,109 +1770,183 @@ static int enetc_alloc_txbdr(struct enetc_bdr *txr) return 0; err_alloc_tso: - enetc_dma_free_bdr(txr, sizeof(union enetc_tx_bd)); + enetc_dma_free_bdr(res); err_alloc_bdr: - vfree(txr->tx_swbd); - txr->tx_swbd = NULL; + vfree(res->tx_swbd); + res->tx_swbd = NULL; return err; } -static void enetc_free_txbdr(struct enetc_bdr *txr) +static void enetc_free_tx_resource(const struct enetc_bdr_resource *res) { - dma_free_coherent(txr->dev, txr->bd_count * TSO_HEADER_SIZE, - txr->tso_headers, txr->tso_headers_dma); - txr->tso_headers = NULL; - - enetc_dma_free_bdr(txr, sizeof(union enetc_tx_bd)); - - vfree(txr->tx_swbd); - txr->tx_swbd = NULL; + dma_free_coherent(res->dev, res->bd_count * TSO_HEADER_SIZE, + res->tso_headers, res->tso_headers_dma); + enetc_dma_free_bdr(res); + vfree(res->tx_swbd); } -static int enetc_alloc_tx_resources(struct enetc_ndev_priv *priv) +static struct enetc_bdr_resource * +enetc_alloc_tx_resources(struct enetc_ndev_priv *priv) { + struct enetc_bdr_resource *tx_res; int i, err; + tx_res = kcalloc(priv->num_tx_rings, sizeof(*tx_res), GFP_KERNEL); + if (!tx_res) + return ERR_PTR(-ENOMEM); + for (i = 0; i < priv->num_tx_rings; i++) { - err = enetc_alloc_txbdr(priv->tx_ring[i]); + struct enetc_bdr *tx_ring = priv->tx_ring[i]; + err = enetc_alloc_tx_resource(&tx_res[i], tx_ring->dev, + tx_ring->bd_count); if (err) goto fail; } - return 0; + return tx_res; fail: while (i-- > 0) - enetc_free_txbdr(priv->tx_ring[i]); + enetc_free_tx_resource(&tx_res[i]); - return err; + kfree(tx_res); + + return ERR_PTR(err); } -static void enetc_free_tx_resources(struct enetc_ndev_priv *priv) +static void enetc_free_tx_resources(const struct enetc_bdr_resource *tx_res, + size_t num_resources) { - int i; + size_t i; - for (i = 0; i < priv->num_tx_rings; i++) - enetc_free_txbdr(priv->tx_ring[i]); + for (i = 0; i < num_resources; i++) + enetc_free_tx_resource(&tx_res[i]); + + kfree(tx_res); } -static int enetc_alloc_rxbdr(struct enetc_bdr *rxr, bool extended) +static int enetc_alloc_rx_resource(struct enetc_bdr_resource *res, + struct device *dev, size_t bd_count, + bool extended) { - size_t size = sizeof(union enetc_rx_bd); int err; - rxr->rx_swbd = vzalloc(rxr->bd_count * sizeof(struct enetc_rx_swbd)); - if (!rxr->rx_swbd) - return -ENOMEM; - + res->dev = dev; + res->bd_count = bd_count; + res->bd_size = sizeof(union enetc_rx_bd); if (extended) - size *= 2; + res->bd_size *= 2; - err = enetc_dma_alloc_bdr(rxr, size); + res->rx_swbd = vzalloc(bd_count * sizeof(struct enetc_rx_swbd)); + if (!res->rx_swbd) + return -ENOMEM; + + err = enetc_dma_alloc_bdr(res); if (err) { - vfree(rxr->rx_swbd); + vfree(res->rx_swbd); return err; } return 0; } -static void enetc_free_rxbdr(struct enetc_bdr *rxr) +static void enetc_free_rx_resource(const struct enetc_bdr_resource *res) { - enetc_dma_free_bdr(rxr, sizeof(union enetc_rx_bd)); - - vfree(rxr->rx_swbd); - rxr->rx_swbd = NULL; + enetc_dma_free_bdr(res); + vfree(res->rx_swbd); } -static int enetc_alloc_rx_resources(struct enetc_ndev_priv *priv, bool extended) +static struct enetc_bdr_resource * +enetc_alloc_rx_resources(struct enetc_ndev_priv *priv, bool extended) { + struct enetc_bdr_resource *rx_res; int i, err; + rx_res = kcalloc(priv->num_rx_rings, sizeof(*rx_res), GFP_KERNEL); + if (!rx_res) + return ERR_PTR(-ENOMEM); + for (i = 0; i < priv->num_rx_rings; i++) { - err = enetc_alloc_rxbdr(priv->rx_ring[i], extended); + struct enetc_bdr *rx_ring = priv->rx_ring[i]; + err = enetc_alloc_rx_resource(&rx_res[i], rx_ring->dev, + rx_ring->bd_count, extended); if (err) goto fail; } - return 0; + return rx_res; fail: while (i-- > 0) - enetc_free_rxbdr(priv->rx_ring[i]); + enetc_free_rx_resource(&rx_res[i]); - return err; + kfree(rx_res); + + return ERR_PTR(err); +} + +static void enetc_free_rx_resources(const struct enetc_bdr_resource *rx_res, + size_t num_resources) +{ + size_t i; + + for (i = 0; i < num_resources; i++) + enetc_free_rx_resource(&rx_res[i]); + + kfree(rx_res); } -static void enetc_free_rx_resources(struct enetc_ndev_priv *priv) +static void enetc_assign_tx_resource(struct enetc_bdr *tx_ring, + const struct enetc_bdr_resource *res) +{ + tx_ring->bd_base = res ? res->bd_base : NULL; + tx_ring->bd_dma_base = res ? res->bd_dma_base : 0; + tx_ring->tx_swbd = res ? res->tx_swbd : NULL; + tx_ring->tso_headers = res ? res->tso_headers : NULL; + tx_ring->tso_headers_dma = res ? res->tso_headers_dma : 0; +} + +static void enetc_assign_rx_resource(struct enetc_bdr *rx_ring, + const struct enetc_bdr_resource *res) +{ + rx_ring->bd_base = res ? res->bd_base : NULL; + rx_ring->bd_dma_base = res ? res->bd_dma_base : 0; + rx_ring->rx_swbd = res ? res->rx_swbd : NULL; +} + +static void enetc_assign_tx_resources(struct enetc_ndev_priv *priv, + const struct enetc_bdr_resource *res) { int i; - for (i = 0; i < priv->num_rx_rings; i++) - enetc_free_rxbdr(priv->rx_ring[i]); + if (priv->tx_res) + enetc_free_tx_resources(priv->tx_res, priv->num_tx_rings); + + for (i = 0; i < priv->num_tx_rings; i++) { + enetc_assign_tx_resource(priv->tx_ring[i], + res ? &res[i] : NULL); + } + + priv->tx_res = res; +} + +static void enetc_assign_rx_resources(struct enetc_ndev_priv *priv, + const struct enetc_bdr_resource *res) +{ + int i; + + if (priv->rx_res) + enetc_free_rx_resources(priv->rx_res, priv->num_rx_rings); + + for (i = 0; i < priv->num_rx_rings; i++) { + enetc_assign_rx_resource(priv->rx_ring[i], + res ? &res[i] : NULL); + } + + priv->rx_res = res; } static void enetc_free_tx_ring(struct enetc_bdr *tx_ring) @@ -2306,6 +2387,7 @@ void enetc_start(struct net_device *ndev) int enetc_open(struct net_device *ndev) { struct enetc_ndev_priv *priv = netdev_priv(ndev); + struct enetc_bdr_resource *tx_res, *rx_res; int num_stack_tx_queues; bool extended; int err; @@ -2320,13 +2402,17 @@ int enetc_open(struct net_device *ndev) if (err) goto err_phy_connect; - err = enetc_alloc_tx_resources(priv); - if (err) + tx_res = enetc_alloc_tx_resources(priv); + if (IS_ERR(tx_res)) { + err = PTR_ERR(tx_res); goto err_alloc_tx; + } - err = enetc_alloc_rx_resources(priv, extended); - if (err) + rx_res = enetc_alloc_rx_resources(priv, extended); + if (IS_ERR(rx_res)) { + err = PTR_ERR(rx_res); goto err_alloc_rx; + } num_stack_tx_queues = enetc_num_stack_tx_queues(priv); @@ -2339,15 +2425,17 @@ int enetc_open(struct net_device *ndev) goto err_set_queues; enetc_tx_onestep_tstamp_init(priv); + enetc_assign_tx_resources(priv, tx_res); + enetc_assign_rx_resources(priv, rx_res); enetc_setup_bdrs(priv, extended); enetc_start(ndev); return 0; err_set_queues: - enetc_free_rx_resources(priv); + enetc_free_rx_resources(rx_res, priv->num_rx_rings); err_alloc_rx: - enetc_free_tx_resources(priv); + enetc_free_tx_resources(tx_res, priv->num_tx_rings); err_alloc_tx: if (priv->phylink) phylink_disconnect_phy(priv->phylink); @@ -2391,8 +2479,11 @@ int enetc_close(struct net_device *ndev) if (priv->phylink) phylink_disconnect_phy(priv->phylink); enetc_free_rxtx_rings(priv); - enetc_free_rx_resources(priv); - enetc_free_tx_resources(priv); + + /* Avoids dangling pointers and also frees old resources */ + enetc_assign_rx_resources(priv, NULL); + enetc_assign_tx_resources(priv, NULL); + enetc_free_irqs(priv); return 0; diff --git a/drivers/net/ethernet/freescale/enetc/enetc.h b/drivers/net/ethernet/freescale/enetc/enetc.h index 416e4138dbaf3..fd161a60a7975 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.h +++ b/drivers/net/ethernet/freescale/enetc/enetc.h @@ -85,6 +85,23 @@ struct enetc_xdp_data { #define ENETC_TX_RING_DEFAULT_SIZE 2048 #define ENETC_DEFAULT_TX_WORK (ENETC_TX_RING_DEFAULT_SIZE / 2) +struct enetc_bdr_resource { + /* Input arguments saved for teardown */ + struct device *dev; /* for DMA mapping */ + size_t bd_count; + size_t bd_size; + + /* Resource proper */ + void *bd_base; /* points to Rx or Tx BD ring */ + dma_addr_t bd_dma_base; + union { + struct enetc_tx_swbd *tx_swbd; + struct enetc_rx_swbd *rx_swbd; + }; + char *tso_headers; + dma_addr_t tso_headers_dma; +}; + struct enetc_bdr { struct device *dev; /* for DMA mapping */ struct net_device *ndev; @@ -344,6 +361,8 @@ struct enetc_ndev_priv { struct enetc_bdr **xdp_tx_ring; struct enetc_bdr *tx_ring[16]; struct enetc_bdr *rx_ring[16]; + const struct enetc_bdr_resource *tx_res; + const struct enetc_bdr_resource *rx_res; struct enetc_cls_rule *cls_rules; From 598ca0d0905608755c86b10c3836499b051571d9 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:30 +0200 Subject: [PATCH 08/12] net: enetc: move phylink_start/stop out of enetc_start/stop We want to introduce a fast interface reconfiguration procedure, which involves temporarily stopping the rings. But we want enetc_start() and enetc_stop() to not restart PHY autoneg, because that can take a few seconds until it completes again. So we need part of enetc_start() and enetc_stop(), but not all of them. Move phylink_start() right next to phylink_of_phy_connect(), and phylink_stop() right next to phylink_disconnect_phy(), both still in ndo_open() and ndo_stop(). Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 26 ++++++++++---------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 543ae8875bc9f..014de5425b811 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -2322,8 +2322,11 @@ static int enetc_phylink_connect(struct net_device *ndev) struct ethtool_eee edata; int err; - if (!priv->phylink) - return 0; /* phy-less mode */ + if (!priv->phylink) { + /* phy-less mode */ + netif_carrier_on(ndev); + return 0; + } err = phylink_of_phy_connect(priv->phylink, priv->dev->of_node, 0); if (err) { @@ -2335,6 +2338,8 @@ static int enetc_phylink_connect(struct net_device *ndev) memset(&edata, 0, sizeof(struct ethtool_eee)); phylink_ethtool_set_eee(priv->phylink, &edata); + phylink_start(priv->phylink); + return 0; } @@ -2376,11 +2381,6 @@ void enetc_start(struct net_device *ndev) enable_irq(irq); } - if (priv->phylink) - phylink_start(priv->phylink); - else - netif_carrier_on(ndev); - netif_tx_start_all_queues(ndev); } @@ -2461,11 +2461,6 @@ void enetc_stop(struct net_device *ndev) napi_disable(&priv->int_vector[i]->napi); } - if (priv->phylink) - phylink_stop(priv->phylink); - else - netif_carrier_off(ndev); - enetc_clear_interrupts(priv); } @@ -2476,8 +2471,13 @@ int enetc_close(struct net_device *ndev) enetc_stop(ndev); enetc_clear_bdrs(priv); - if (priv->phylink) + if (priv->phylink) { + phylink_stop(priv->phylink); phylink_disconnect_phy(priv->phylink); + } else { + netif_carrier_off(ndev); + } + enetc_free_rxtx_rings(priv); /* Avoids dangling pointers and also frees old resources */ From 5093406c784f83f7fc6cc1f1bd49c2b062275954 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:31 +0200 Subject: [PATCH 09/12] net: enetc: implement ring reconfiguration procedure for PTP RX timestamping The crude enetc_stop() -> enetc_open() mechanism suffers from 2 problems: 1. improper error checking 2. it involves phylink_stop() -> phylink_start() which loses the link Right now, the driver is prepared to offer a better alternative: a ring reconfiguration procedure which takes the RX BD size (normal or extended) as argument. It allocates new resources (failing if that fails), stops the traffic, and assigns the new resources to the rings. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 68 ++++++++++++++++---- 1 file changed, 56 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index 014de5425b811..dc54fe7b4e863 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -2489,6 +2489,46 @@ int enetc_close(struct net_device *ndev) return 0; } +static int enetc_reconfigure(struct enetc_ndev_priv *priv, bool extended) +{ + struct enetc_bdr_resource *tx_res, *rx_res; + int err; + + ASSERT_RTNL(); + + /* If the interface is down, do nothing. */ + if (!netif_running(priv->ndev)) + return 0; + + tx_res = enetc_alloc_tx_resources(priv); + if (IS_ERR(tx_res)) { + err = PTR_ERR(tx_res); + goto out; + } + + rx_res = enetc_alloc_rx_resources(priv, extended); + if (IS_ERR(rx_res)) { + err = PTR_ERR(rx_res); + goto out_free_tx_res; + } + + enetc_stop(priv->ndev); + enetc_clear_bdrs(priv); + enetc_free_rxtx_rings(priv); + + enetc_assign_tx_resources(priv, tx_res); + enetc_assign_rx_resources(priv, rx_res); + enetc_setup_bdrs(priv, extended); + enetc_start(priv->ndev); + + return 0; + +out_free_tx_res: + enetc_free_tx_resources(tx_res, priv->num_tx_rings); +out: + return err; +} + int enetc_setup_tc_mqprio(struct net_device *ndev, void *type_data) { struct enetc_ndev_priv *priv = netdev_priv(ndev); @@ -2681,43 +2721,47 @@ void enetc_set_features(struct net_device *ndev, netdev_features_t features) static int enetc_hwtstamp_set(struct net_device *ndev, struct ifreq *ifr) { struct enetc_ndev_priv *priv = netdev_priv(ndev); + int err, new_offloads = priv->active_offloads; struct hwtstamp_config config; - int ao; if (copy_from_user(&config, ifr->ifr_data, sizeof(config))) return -EFAULT; switch (config.tx_type) { case HWTSTAMP_TX_OFF: - priv->active_offloads &= ~ENETC_F_TX_TSTAMP_MASK; + new_offloads &= ~ENETC_F_TX_TSTAMP_MASK; break; case HWTSTAMP_TX_ON: - priv->active_offloads &= ~ENETC_F_TX_TSTAMP_MASK; - priv->active_offloads |= ENETC_F_TX_TSTAMP; + new_offloads &= ~ENETC_F_TX_TSTAMP_MASK; + new_offloads |= ENETC_F_TX_TSTAMP; break; case HWTSTAMP_TX_ONESTEP_SYNC: - priv->active_offloads &= ~ENETC_F_TX_TSTAMP_MASK; - priv->active_offloads |= ENETC_F_TX_ONESTEP_SYNC_TSTAMP; + new_offloads &= ~ENETC_F_TX_TSTAMP_MASK; + new_offloads |= ENETC_F_TX_ONESTEP_SYNC_TSTAMP; break; default: return -ERANGE; } - ao = priv->active_offloads; switch (config.rx_filter) { case HWTSTAMP_FILTER_NONE: - priv->active_offloads &= ~ENETC_F_RX_TSTAMP; + new_offloads &= ~ENETC_F_RX_TSTAMP; break; default: - priv->active_offloads |= ENETC_F_RX_TSTAMP; + new_offloads |= ENETC_F_RX_TSTAMP; config.rx_filter = HWTSTAMP_FILTER_ALL; } - if (netif_running(ndev) && ao != priv->active_offloads) { - enetc_close(ndev); - enetc_open(ndev); + if ((new_offloads ^ priv->active_offloads) & ENETC_F_RX_TSTAMP) { + bool extended = !!(new_offloads & ENETC_F_RX_TSTAMP); + + err = enetc_reconfigure(priv, extended); + if (err) + return err; } + priv->active_offloads = new_offloads; + return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ? -EFAULT : 0; } From 766338c79b1045866870b795882c4d42c64c9c53 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:32 +0200 Subject: [PATCH 10/12] net: enetc: rename "xdp" and "dev" in enetc_setup_bpf() Follow the convention from this driver, which is to name "struct net_device *" as "ndev", and the convention from other drivers, to name "struct netdev_bpf *" as "bpf". Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 16 ++++++++-------- drivers/net/ethernet/freescale/enetc/enetc.h | 2 +- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index dc54fe7b4e863..ce3319f55573d 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -2586,10 +2586,10 @@ int enetc_setup_tc_mqprio(struct net_device *ndev, void *type_data) return 0; } -static int enetc_setup_xdp_prog(struct net_device *dev, struct bpf_prog *prog, +static int enetc_setup_xdp_prog(struct net_device *ndev, struct bpf_prog *prog, struct netlink_ext_ack *extack) { - struct enetc_ndev_priv *priv = netdev_priv(dev); + struct enetc_ndev_priv *priv = netdev_priv(ndev); struct bpf_prog *old_prog; bool is_up; int i; @@ -2597,9 +2597,9 @@ static int enetc_setup_xdp_prog(struct net_device *dev, struct bpf_prog *prog, /* The buffer layout is changing, so we need to drain the old * RX buffers and seed new ones. */ - is_up = netif_running(dev); + is_up = netif_running(ndev); if (is_up) - dev_close(dev); + dev_close(ndev); old_prog = xchg(&priv->xdp_prog, prog); if (old_prog) @@ -2617,16 +2617,16 @@ static int enetc_setup_xdp_prog(struct net_device *dev, struct bpf_prog *prog, } if (is_up) - return dev_open(dev, extack); + return dev_open(ndev, extack); return 0; } -int enetc_setup_bpf(struct net_device *dev, struct netdev_bpf *xdp) +int enetc_setup_bpf(struct net_device *ndev, struct netdev_bpf *bpf) { - switch (xdp->command) { + switch (bpf->command) { case XDP_SETUP_PROG: - return enetc_setup_xdp_prog(dev, xdp->prog, xdp->extack); + return enetc_setup_xdp_prog(ndev, bpf->prog, bpf->extack); default: return -EINVAL; } diff --git a/drivers/net/ethernet/freescale/enetc/enetc.h b/drivers/net/ethernet/freescale/enetc/enetc.h index fd161a60a7975..6a87aa972e1ea 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.h +++ b/drivers/net/ethernet/freescale/enetc/enetc.h @@ -415,7 +415,7 @@ struct net_device_stats *enetc_get_stats(struct net_device *ndev); void enetc_set_features(struct net_device *ndev, netdev_features_t features); int enetc_ioctl(struct net_device *ndev, struct ifreq *rq, int cmd); int enetc_setup_tc_mqprio(struct net_device *ndev, void *type_data); -int enetc_setup_bpf(struct net_device *dev, struct netdev_bpf *xdp); +int enetc_setup_bpf(struct net_device *ndev, struct netdev_bpf *bpf); int enetc_xdp_xmit(struct net_device *ndev, int num_frames, struct xdp_frame **frames, u32 flags); From c33bfaf91c4ca6c859b1184396c0be2c1a94e745 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:33 +0200 Subject: [PATCH 11/12] net: enetc: set up XDP program under enetc_reconfigure() Offloading a BPF program to the RX path of the driver suffers from the same problems as the PTP reconfiguration - improper error checking can leave the driver in an invalid state, and the link on the PHY is lost. Reuse the enetc_reconfigure() procedure, but here, we need to run some code in the middle of the ring reconfiguration procedure - while the interface is still down. Introduce a callback which makes that possible. Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 51 ++++++++++++-------- 1 file changed, 32 insertions(+), 19 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index ce3319f55573d..eeff69336a803 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -2489,16 +2489,24 @@ int enetc_close(struct net_device *ndev) return 0; } -static int enetc_reconfigure(struct enetc_ndev_priv *priv, bool extended) +static int enetc_reconfigure(struct enetc_ndev_priv *priv, bool extended, + int (*cb)(struct enetc_ndev_priv *priv, void *ctx), + void *ctx) { struct enetc_bdr_resource *tx_res, *rx_res; int err; ASSERT_RTNL(); - /* If the interface is down, do nothing. */ - if (!netif_running(priv->ndev)) + /* If the interface is down, run the callback right away, + * without reconfiguration. + */ + if (!netif_running(priv->ndev)) { + if (cb) + cb(priv, ctx); + return 0; + } tx_res = enetc_alloc_tx_resources(priv); if (IS_ERR(tx_res)) { @@ -2516,6 +2524,10 @@ static int enetc_reconfigure(struct enetc_ndev_priv *priv, bool extended) enetc_clear_bdrs(priv); enetc_free_rxtx_rings(priv); + /* Interface is down, run optional callback now */ + if (cb) + cb(priv, ctx); + enetc_assign_tx_resources(priv, tx_res); enetc_assign_rx_resources(priv, rx_res); enetc_setup_bdrs(priv, extended); @@ -2586,21 +2598,11 @@ int enetc_setup_tc_mqprio(struct net_device *ndev, void *type_data) return 0; } -static int enetc_setup_xdp_prog(struct net_device *ndev, struct bpf_prog *prog, - struct netlink_ext_ack *extack) +static int enetc_reconfigure_xdp_cb(struct enetc_ndev_priv *priv, void *ctx) { - struct enetc_ndev_priv *priv = netdev_priv(ndev); - struct bpf_prog *old_prog; - bool is_up; + struct bpf_prog *old_prog, *prog = ctx; int i; - /* The buffer layout is changing, so we need to drain the old - * RX buffers and seed new ones. - */ - is_up = netif_running(ndev); - if (is_up) - dev_close(ndev); - old_prog = xchg(&priv->xdp_prog, prog); if (old_prog) bpf_prog_put(old_prog); @@ -2616,12 +2618,23 @@ static int enetc_setup_xdp_prog(struct net_device *ndev, struct bpf_prog *prog, rx_ring->buffer_offset = ENETC_RXB_PAD; } - if (is_up) - return dev_open(ndev, extack); - return 0; } +static int enetc_setup_xdp_prog(struct net_device *ndev, struct bpf_prog *prog, + struct netlink_ext_ack *extack) +{ + struct enetc_ndev_priv *priv = netdev_priv(ndev); + bool extended; + + extended = !!(priv->active_offloads & ENETC_F_RX_TSTAMP); + + /* The buffer layout is changing, so we need to drain the old + * RX buffers and seed new ones. + */ + return enetc_reconfigure(priv, extended, enetc_reconfigure_xdp_cb, prog); +} + int enetc_setup_bpf(struct net_device *ndev, struct netdev_bpf *bpf) { switch (bpf->command) { @@ -2755,7 +2768,7 @@ static int enetc_hwtstamp_set(struct net_device *ndev, struct ifreq *ifr) if ((new_offloads ^ priv->active_offloads) & ENETC_F_RX_TSTAMP) { bool extended = !!(new_offloads & ENETC_F_RX_TSTAMP); - err = enetc_reconfigure(priv, extended); + err = enetc_reconfigure(priv, extended, NULL, NULL); if (err) return err; } From ff58fda0909618389f40647cba28a354a609e052 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 18 Jan 2023 01:02:34 +0200 Subject: [PATCH 12/12] net: enetc: prioritize ability to go down over packet processing napi_synchronize() from enetc_stop() waits until the softirq has finished execution and no longer wants to be rescheduled. However under high traffic load, this will never happen, and the interface can never be closed. The problem is the fact that the NAPI poll routine is written to update the consumer index which makes the device want to put more buffers in the RX ring, which restarts the madness again. Browsing around, it seems that some drivers like i40e keep a bit (__I40E_VSI_DOWN) which they use as communication between the control path and the data path. But that isn't my first choice, because complications ensue - since the enetc hardirq may trigger while we are in a theoretical ENETC_DOWN state, it may happen that enetc_msix() masks it, but enetc_poll() never unmasks it. To prevent a stall in that case, one would need to schedule all NAPI instances when ENETC_DOWN gets cleared, to process what's pending. I find it more desirable for the control path - enetc_stop() - to just quiesce the RX ring and let the softirq finish what remains there, without any explicit communication, just by making hardware not provide any more packets. This seems possible with the Enable bit of the RX BD ring (RBaMR[EN]). I can't seem to find an exact definition of what this bit does, but when the RX ring is disabled, the port seems to no longer update the producer index, and not react to software updates of the consumer index. In fact, the RBaMR[EN] bit is already toggled by the driver, but too late for what we want: enetc_close() -> enetc_stop() -> napi_synchronize() -> enetc_clear_bdrs() -> enetc_clear_rxbdr() The enetc_clear_bdrs() function contains not only logic to disable the RX and TX rings, but also logic to wait for the TX ring stop being busy. We split enetc_clear_bdrs() into enetc_disable_bdrs() and enetc_wait_bdrs(). One needs to run before napi_synchronize() and the other after (NAPI also processes TX completions, so we maximize our chances of not waiting for the ENETC_TBSR_BUSY bit - unless a packet is stuck for some reason, ofc). We also split off enetc_enable_bdrs() from enetc_setup_bdrs(), and call this from the mirror position in enetc_start() compared to enetc_stop(), i.e. right before netif_tx_start_all_queues(). Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/freescale/enetc/enetc.c | 81 +++++++++++++++----- 1 file changed, 63 insertions(+), 18 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c index eeff69336a803..6e54d49176ad8 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc.c +++ b/drivers/net/ethernet/freescale/enetc/enetc.c @@ -2088,7 +2088,7 @@ static void enetc_setup_txbdr(struct enetc_hw *hw, struct enetc_bdr *tx_ring) /* enable Tx ints by setting pkt thr to 1 */ enetc_txbdr_wr(hw, idx, ENETC_TBICR0, ENETC_TBICR0_ICEN | 0x1); - tbmr = ENETC_TBMR_EN | ENETC_TBMR_SET_PRIO(tx_ring->prio); + tbmr = ENETC_TBMR_SET_PRIO(tx_ring->prio); if (tx_ring->ndev->features & NETIF_F_HW_VLAN_CTAG_TX) tbmr |= ENETC_TBMR_VIH; @@ -2104,7 +2104,7 @@ static void enetc_setup_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring, bool extended) { int idx = rx_ring->index; - u32 rbmr; + u32 rbmr = 0; enetc_rxbdr_wr(hw, idx, ENETC_RBBAR0, lower_32_bits(rx_ring->bd_dma_base)); @@ -2131,8 +2131,6 @@ static void enetc_setup_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring, /* enable Rx ints by setting pkt thr to 1 */ enetc_rxbdr_wr(hw, idx, ENETC_RBICR0, ENETC_RBICR0_ICEN | 0x1); - rbmr = ENETC_RBMR_EN; - rx_ring->ext_en = extended; if (rx_ring->ext_en) rbmr |= ENETC_RBMR_BDS; @@ -2151,7 +2149,6 @@ static void enetc_setup_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring, enetc_refill_rx_ring(rx_ring, enetc_bd_unused(rx_ring)); enetc_unlock_mdio(); - /* enable ring */ enetc_rxbdr_wr(hw, idx, ENETC_RBMR, rbmr); } @@ -2167,7 +2164,39 @@ static void enetc_setup_bdrs(struct enetc_ndev_priv *priv, bool extended) enetc_setup_rxbdr(hw, priv->rx_ring[i], extended); } -static void enetc_clear_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) +static void enetc_enable_txbdr(struct enetc_hw *hw, struct enetc_bdr *tx_ring) +{ + int idx = tx_ring->index; + u32 tbmr; + + tbmr = enetc_txbdr_rd(hw, idx, ENETC_TBMR); + tbmr |= ENETC_TBMR_EN; + enetc_txbdr_wr(hw, idx, ENETC_TBMR, tbmr); +} + +static void enetc_enable_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) +{ + int idx = rx_ring->index; + u32 rbmr; + + rbmr = enetc_rxbdr_rd(hw, idx, ENETC_RBMR); + rbmr |= ENETC_RBMR_EN; + enetc_rxbdr_wr(hw, idx, ENETC_RBMR, rbmr); +} + +static void enetc_enable_bdrs(struct enetc_ndev_priv *priv) +{ + struct enetc_hw *hw = &priv->si->hw; + int i; + + for (i = 0; i < priv->num_tx_rings; i++) + enetc_enable_txbdr(hw, priv->tx_ring[i]); + + for (i = 0; i < priv->num_rx_rings; i++) + enetc_enable_rxbdr(hw, priv->rx_ring[i]); +} + +static void enetc_disable_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) { int idx = rx_ring->index; @@ -2175,13 +2204,30 @@ static void enetc_clear_rxbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) enetc_rxbdr_wr(hw, idx, ENETC_RBMR, 0); } -static void enetc_clear_txbdr(struct enetc_hw *hw, struct enetc_bdr *tx_ring) +static void enetc_disable_txbdr(struct enetc_hw *hw, struct enetc_bdr *rx_ring) { - int delay = 8, timeout = 100; - int idx = tx_ring->index; + int idx = rx_ring->index; /* disable EN bit on ring */ enetc_txbdr_wr(hw, idx, ENETC_TBMR, 0); +} + +static void enetc_disable_bdrs(struct enetc_ndev_priv *priv) +{ + struct enetc_hw *hw = &priv->si->hw; + int i; + + for (i = 0; i < priv->num_tx_rings; i++) + enetc_disable_txbdr(hw, priv->tx_ring[i]); + + for (i = 0; i < priv->num_rx_rings; i++) + enetc_disable_rxbdr(hw, priv->rx_ring[i]); +} + +static void enetc_wait_txbdr(struct enetc_hw *hw, struct enetc_bdr *tx_ring) +{ + int delay = 8, timeout = 100; + int idx = tx_ring->index; /* wait for busy to clear */ while (delay < timeout && @@ -2195,18 +2241,13 @@ static void enetc_clear_txbdr(struct enetc_hw *hw, struct enetc_bdr *tx_ring) idx); } -static void enetc_clear_bdrs(struct enetc_ndev_priv *priv) +static void enetc_wait_bdrs(struct enetc_ndev_priv *priv) { struct enetc_hw *hw = &priv->si->hw; int i; for (i = 0; i < priv->num_tx_rings; i++) - enetc_clear_txbdr(hw, priv->tx_ring[i]); - - for (i = 0; i < priv->num_rx_rings; i++) - enetc_clear_rxbdr(hw, priv->rx_ring[i]); - - udelay(1); + enetc_wait_txbdr(hw, priv->tx_ring[i]); } static int enetc_setup_irqs(struct enetc_ndev_priv *priv) @@ -2381,6 +2422,8 @@ void enetc_start(struct net_device *ndev) enable_irq(irq); } + enetc_enable_bdrs(priv); + netif_tx_start_all_queues(ndev); } @@ -2452,6 +2495,8 @@ void enetc_stop(struct net_device *ndev) netif_tx_stop_all_queues(ndev); + enetc_disable_bdrs(priv); + for (i = 0; i < priv->bdr_int_num; i++) { int irq = pci_irq_vector(priv->si->pdev, ENETC_BDR_INT_BASE_IDX + i); @@ -2461,6 +2506,8 @@ void enetc_stop(struct net_device *ndev) napi_disable(&priv->int_vector[i]->napi); } + enetc_wait_bdrs(priv); + enetc_clear_interrupts(priv); } @@ -2469,7 +2516,6 @@ int enetc_close(struct net_device *ndev) struct enetc_ndev_priv *priv = netdev_priv(ndev); enetc_stop(ndev); - enetc_clear_bdrs(priv); if (priv->phylink) { phylink_stop(priv->phylink); @@ -2521,7 +2567,6 @@ static int enetc_reconfigure(struct enetc_ndev_priv *priv, bool extended, } enetc_stop(priv->ndev); - enetc_clear_bdrs(priv); enetc_free_rxtx_rings(priv); /* Interface is down, run optional callback now */