generic: 5.15: backport stmmac patches to change MTU

Backport stmmac patches to change MTU while the interface is up.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>

target/linux/generic/backport-5.15/775-v6.0-01-net-ethernet-stmicro-stmmac-move-queue-reset-to-dedi.patch

@@ -0,0 +1,142 @@
+From f9ec5723c3dbfcede9c7b0dcdf85e401ce16316c Mon Sep 17 00:00:00 2001
+From: Christian Marangi <ansuelsmth@gmail.com>
+Date: Sat, 23 Jul 2022 16:29:29 +0200
+Subject: [PATCH 1/5] net: ethernet: stmicro: stmmac: move queue reset to
+ dedicated functions
+
+Move queue reset to dedicated functions. This aside from a simple
+cleanup is also required to allocate a dma conf without resetting the tx
+queue while the device is temporarily detached as now the reset is not
+part of the dma init function and can be done later in the code flow.
+
+Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+---
+ .../net/ethernet/stmicro/stmmac/stmmac_main.c | 59 ++++++++++---------
+ 1 file changed, 31 insertions(+), 28 deletions(-)
+
+--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
++++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+@@ -130,6 +130,9 @@ static irqreturn_t stmmac_mac_interrupt(
+ static irqreturn_t stmmac_safety_interrupt(int irq, void *dev_id);
+ static irqreturn_t stmmac_msi_intr_tx(int irq, void *data);
+ static irqreturn_t stmmac_msi_intr_rx(int irq, void *data);
++static void stmmac_reset_rx_queue(struct stmmac_priv *priv, u32 queue);
++static void stmmac_reset_tx_queue(struct stmmac_priv *priv, u32 queue);
++static void stmmac_reset_queues_param(struct stmmac_priv *priv);
+ static void stmmac_tx_timer_arm(struct stmmac_priv *priv, u32 queue);
+ static void stmmac_flush_tx_descriptors(struct stmmac_priv *priv, int queue);
+ 
+@@ -1696,9 +1699,6 @@ static int __init_dma_rx_desc_rings(stru
+ 			return -ENOMEM;
+ 	}
+ 
+-	rx_q->cur_rx = 0;
+-	rx_q->dirty_rx = 0;
+-
+ 	/* Setup the chained descriptor addresses */
+ 	if (priv->mode == STMMAC_CHAIN_MODE) {
+ 		if (priv->extend_desc)
+@@ -1804,12 +1804,6 @@ static int __init_dma_tx_desc_rings(stru
+ 		tx_q->tx_skbuff[i] = NULL;
+ 	}
+ 
+-	tx_q->dirty_tx = 0;
+-	tx_q->cur_tx = 0;
+-	tx_q->mss = 0;
+-
+-	netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, queue));
+-
+ 	return 0;
+ }
+ 
+@@ -2678,10 +2672,7 @@ static void stmmac_tx_err(struct stmmac_
+ 	stmmac_stop_tx_dma(priv, chan);
+ 	dma_free_tx_skbufs(priv, chan);
+ 	stmmac_clear_tx_descriptors(priv, chan);
+-	tx_q->dirty_tx = 0;
+-	tx_q->cur_tx = 0;
+-	tx_q->mss = 0;
+-	netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, chan));
++	stmmac_reset_tx_queue(priv, chan);
+ 	stmmac_init_tx_chan(priv, priv->ioaddr, priv->plat->dma_cfg,
+ 			    tx_q->dma_tx_phy, chan);
+ 	stmmac_start_tx_dma(priv, chan);
+@@ -3756,6 +3747,8 @@ static int stmmac_open(struct net_device
+ 		goto init_error;
+ 	}
+ 
++	stmmac_reset_queues_param(priv);
++
+ 	ret = stmmac_hw_setup(dev, true);
+ 	if (ret < 0) {
+ 		netdev_err(priv->dev, "%s: Hw setup failed\n", __func__);
+@@ -6395,6 +6388,7 @@ void stmmac_enable_rx_queue(struct stmma
+ 		return;
+ 	}
+ 
++	stmmac_reset_rx_queue(priv, queue);
+ 	stmmac_clear_rx_descriptors(priv, queue);
+ 
+ 	stmmac_init_rx_chan(priv, priv->ioaddr, priv->plat->dma_cfg,
+@@ -6456,6 +6450,7 @@ void stmmac_enable_tx_queue(struct stmma
+ 		return;
+ 	}
+ 
++	stmmac_reset_tx_queue(priv, queue);
+ 	stmmac_clear_tx_descriptors(priv, queue);
+ 
+ 	stmmac_init_tx_chan(priv, priv->ioaddr, priv->plat->dma_cfg,
+@@ -7383,6 +7378,25 @@ int stmmac_suspend(struct device *dev)
+ }
+ EXPORT_SYMBOL_GPL(stmmac_suspend);
+ 
++static void stmmac_reset_rx_queue(struct stmmac_priv *priv, u32 queue)
++{
++	struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
++
++	rx_q->cur_rx = 0;
++	rx_q->dirty_rx = 0;
++}
++
++static void stmmac_reset_tx_queue(struct stmmac_priv *priv, u32 queue)
++{
++	struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];
++
++	tx_q->cur_tx = 0;
++	tx_q->dirty_tx = 0;
++	tx_q->mss = 0;
++
++	netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, queue));
++}
++
+ /**
+  * stmmac_reset_queues_param - reset queue parameters
+  * @priv: device pointer
+@@ -7393,22 +7407,11 @@ static void stmmac_reset_queues_param(st
+ 	u32 tx_cnt = priv->plat->tx_queues_to_use;
+ 	u32 queue;
+ 
+-	for (queue = 0; queue < rx_cnt; queue++) {
+-		struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
++	for (queue = 0; queue < rx_cnt; queue++)
++		stmmac_reset_rx_queue(priv, queue);
+ 
+-		rx_q->cur_rx = 0;
+-		rx_q->dirty_rx = 0;
+-	}
+-
+-	for (queue = 0; queue < tx_cnt; queue++) {
+-		struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];
+-
+-		tx_q->cur_tx = 0;
+-		tx_q->dirty_tx = 0;
+-		tx_q->mss = 0;
+-
+-		netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, queue));
+-	}
++	for (queue = 0; queue < tx_cnt; queue++)
++		stmmac_reset_tx_queue(priv, queue);
+ }
+ 
+ /**

target/linux/generic/backport-5.15/775-v6.0-02-net-ethernet-stmicro-stmmac-first-disable-all-queues.patch

@@ -0,0 +1,37 @@
+From 7028471edb646bfc532fec0973e50e784cdcb7c6 Mon Sep 17 00:00:00 2001
+From: Christian Marangi <ansuelsmth@gmail.com>
+Date: Sat, 23 Jul 2022 16:29:30 +0200
+Subject: [PATCH 2/5] net: ethernet: stmicro: stmmac: first disable all queues
+ and disconnect in release
+
+Disable all queues and disconnect before tx_disable in stmmac_release to
+prevent a corner case where packet may be still queued at the same time
+tx_disable is called resulting in kernel panic if some packet still has
+to be processed.
+
+Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+---
+ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
++++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+@@ -3808,8 +3808,6 @@ static int stmmac_release(struct net_dev
+ 	struct stmmac_priv *priv = netdev_priv(dev);
+ 	u32 chan;
+ 
+-	netif_tx_disable(dev);
+-
+ 	if (device_may_wakeup(priv->device))
+ 		phylink_speed_down(priv->phylink, false);
+ 	/* Stop and disconnect the PHY */
+@@ -3821,6 +3819,8 @@ static int stmmac_release(struct net_dev
+ 	for (chan = 0; chan < priv->plat->tx_queues_to_use; chan++)
+ 		hrtimer_cancel(&priv->tx_queue[chan].txtimer);
+ 
++	netif_tx_disable(dev);
++
+ 	/* Free the IRQ lines */
+ 	stmmac_free_irq(dev, REQ_IRQ_ERR_ALL, 0);
+ 

target/linux/generic/backport-5.15/775-v6.0-05-net-ethernet-stmicro-stmmac-permit-MTU-change-with-i.patch

@@ -0,0 +1,73 @@
+From 3470079687448abac42deb62774253be1d6bdef3 Mon Sep 17 00:00:00 2001
+From: Christian Marangi <ansuelsmth@gmail.com>
+Date: Sat, 23 Jul 2022 16:29:33 +0200
+Subject: [PATCH 5/5] net: ethernet: stmicro: stmmac: permit MTU change with
+ interface up
+
+Remove the limitation where the interface needs to be down to change
+MTU by releasing and opening the stmmac driver to set the new MTU.
+Also call the set_filter function to correctly init the port.
+This permits to remove the EBUSY error while the ethernet port is
+running permitting a correct MTU change if for example a DSA request
+a MTU change for a switch CPU port.
+
+Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+---
+ .../net/ethernet/stmicro/stmmac/stmmac_main.c | 30 +++++++++++++++----
+ 1 file changed, 24 insertions(+), 6 deletions(-)
+
+--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
++++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+@@ -5597,18 +5597,15 @@ static int stmmac_change_mtu(struct net_
+ {
+ 	struct stmmac_priv *priv = netdev_priv(dev);
+ 	int txfifosz = priv->plat->tx_fifo_size;
++	struct stmmac_dma_conf *dma_conf;
+ 	const int mtu = new_mtu;
++	int ret;
+ 
+ 	if (txfifosz == 0)
+ 		txfifosz = priv->dma_cap.tx_fifo_size;
+ 
+ 	txfifosz /= priv->plat->tx_queues_to_use;
+ 
+-	if (netif_running(dev)) {
+-		netdev_err(priv->dev, "must be stopped to change its MTU\n");
+-		return -EBUSY;
+-	}
+-
+ 	if (stmmac_xdp_is_enabled(priv) && new_mtu > ETH_DATA_LEN) {
+ 		netdev_dbg(priv->dev, "Jumbo frames not supported for XDP\n");
+ 		return -EINVAL;
+@@ -5620,8 +5617,29 @@ static int stmmac_change_mtu(struct net_
+ 	if ((txfifosz < new_mtu) || (new_mtu > BUF_SIZE_16KiB))
+ 		return -EINVAL;
+ 
+-	dev->mtu = mtu;
++	if (netif_running(dev)) {
++		netdev_dbg(priv->dev, "restarting interface to change its MTU\n");
++		/* Try to allocate the new DMA conf with the new mtu */
++		dma_conf = stmmac_setup_dma_desc(priv, mtu);
++		if (IS_ERR(dma_conf)) {
++			netdev_err(priv->dev, "failed allocating new dma conf for new MTU %d\n",
++				   mtu);
++			return PTR_ERR(dma_conf);
++		}
++
++		stmmac_release(dev);
++
++		ret = __stmmac_open(dev, dma_conf);
++		kfree(dma_conf);
++		if (ret) {
++			netdev_err(priv->dev, "failed reopening the interface after MTU change\n");
++			return ret;
++		}
++
++		stmmac_set_rx_mode(dev);
++	}
+ 
++	dev->mtu = mtu;
+ 	netdev_update_features(dev);
+ 
+ 	return 0;