bcm4908: backport recent bcm4908_enet changes

This includes 5.12 fix and 5.13 improvements.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
(cherry picked from commit 7091e312307f4563d4a7afb5946140120cfa87fa)

4 files changed, 431 insertions, 0 deletions

diff --git a/target/linux/bcm4908/patches-5.4/073-v5.12-0013-net-broadcom-BCM4908_ENET-should-not-default-to-y-un.patch b/target/linux/bcm4908/patches-5.4/073-v5.12-0013-net-broadcom-BCM4908_ENET-should-not-default-to-y-un.patch
new file mode 100644
index 0000000000..43e5ee01bf
--- /dev/null
+++ b/target/linux/bcm4908/patches-5.4/073-v5.12-0013-net-broadcom-BCM4908_ENET-should-not-default-to-y-un.patch
@@ -0,0 +1,33 @@
+From a3bc483216650a7232559bf0a1debfbabff3e12c Mon Sep 17 00:00:00 2001
+From: Geert Uytterhoeven <geert+renesas@glider.be>
+Date: Tue, 16 Mar 2021 15:03:41 +0100
+Subject: [PATCH] net: broadcom: BCM4908_ENET should not default to y,
+ unconditionally
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Merely enabling compile-testing should not enable additional code.
+To fix this, restrict the automatic enabling of BCM4908_ENET to
+ARCH_BCM4908.
+
+Fixes: 4feffeadbcb2e5b1 ("net: broadcom: bcm4908enet: add BCM4908 controller driver")
+Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
+Acked-by: Florian Fainelli <f.fainelli@gmail.com>
+Acked-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/broadcom/Kconfig | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/net/ethernet/broadcom/Kconfig
++++ b/drivers/net/ethernet/broadcom/Kconfig
+@@ -54,7 +54,7 @@ config B44_PCI
+ config BCM4908_ENET
+ 	tristate "Broadcom BCM4908 internal mac support"
+ 	depends on ARCH_BCM4908 || COMPILE_TEST
+-	default y
++	default y if ARCH_BCM4908
+ 	help
+ 	  This driver supports Ethernet controller integrated into Broadcom
+ 	  BCM4908 family SoCs.
diff --git a/target/linux/bcm4908/patches-5.4/074-v5.13-0001-net-broadcom-bcm4908_enet-read-MAC-from-OF.patch b/target/linux/bcm4908/patches-5.4/074-v5.13-0001-net-broadcom-bcm4908_enet-read-MAC-from-OF.patch
new file mode 100644
index 0000000000..4b8e1f83b8
--- /dev/null
+++ b/target/linux/bcm4908/patches-5.4/074-v5.13-0001-net-broadcom-bcm4908_enet-read-MAC-from-OF.patch
@@ -0,0 +1,48 @@
+From 3559c1ea4336636c886002996d50805365d3055c Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Wed, 10 Mar 2021 09:48:13 +0100
+Subject: [PATCH] net: broadcom: bcm4908_enet: read MAC from OF
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+BCM4908 devices have MAC address accessible using NVMEM so it's needed
+to use OF helper for reading it.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/broadcom/bcm4908_enet.c | 8 +++++++-
+ 1 file changed, 7 insertions(+), 1 deletion(-)
+
+--- a/drivers/net/ethernet/broadcom/bcm4908_enet.c
++++ b/drivers/net/ethernet/broadcom/bcm4908_enet.c
+@@ -9,6 +9,7 @@
+ #include <linux/interrupt.h>
+ #include <linux/module.h>
+ #include <linux/of.h>
++#include <linux/of_net.h>
+ #include <linux/platform_device.h>
+ #include <linux/slab.h>
+ #include <linux/string.h>
+@@ -620,6 +621,7 @@ static int bcm4908_enet_probe(struct pla
+ 	struct device *dev = &pdev->dev;
+ 	struct net_device *netdev;
+ 	struct bcm4908_enet *enet;
++	const u8 *mac;
+ 	int err;
+ 
+ 	netdev = devm_alloc_etherdev(dev, sizeof(*enet));
+@@ -647,7 +649,11 @@ static int bcm4908_enet_probe(struct pla
+ 		return err;
+ 
+ 	SET_NETDEV_DEV(netdev, &pdev->dev);
+-	eth_hw_addr_random(netdev);
++	mac = of_get_mac_address(dev->of_node);
++	if (!IS_ERR(mac))
++		ether_addr_copy(netdev->dev_addr, mac);
++	else
++		eth_hw_addr_random(netdev);
+ 	netdev->netdev_ops = &bcm4908_enet_netdev_ops;
+ 	netdev->min_mtu = ETH_ZLEN;
+ 	netdev->mtu = ETH_DATA_LEN;
diff --git a/target/linux/bcm4908/patches-5.4/074-v5.13-0002-dt-bindings-net-bcm4908-enet-add-optional-TX-interru.patch b/target/linux/bcm4908/patches-5.4/074-v5.13-0002-dt-bindings-net-bcm4908-enet-add-optional-TX-interru.patch
new file mode 100644
index 0000000000..b61437a2de
--- /dev/null
+++ b/target/linux/bcm4908/patches-5.4/074-v5.13-0002-dt-bindings-net-bcm4908-enet-add-optional-TX-interru.patch
@@ -0,0 +1,50 @@
+From ab4dda7a8cb7e55ea3d92fd5e249cf6f5396028c Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Thu, 11 Mar 2021 13:35:20 +0100
+Subject: [PATCH] dt-bindings: net: bcm4908-enet: add optional TX interrupt
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+I discovered that hardware actually supports two interrupts, one per DMA
+channel (RX and TX).
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ .../bindings/net/brcm,bcm4908-enet.yaml         | 17 +++++++++++++----
+ 1 file changed, 13 insertions(+), 4 deletions(-)
+
+--- a/Documentation/devicetree/bindings/net/brcm,bcm4908-enet.yaml
++++ b/Documentation/devicetree/bindings/net/brcm,bcm4908-enet.yaml
+@@ -22,10 +22,18 @@ properties:
+     maxItems: 1
+ 
+   interrupts:
+-    description: RX interrupt
++    minItems: 1
++    maxItems: 2
++    items:
++      - description: RX interrupt
++      - description: TX interrupt
+ 
+   interrupt-names:
+-    const: rx
++    minItems: 1
++    maxItems: 2
++    items:
++      - const: rx
++      - const: tx
+ 
+ required:
+   - reg
+@@ -43,6 +51,7 @@ examples:
+         compatible = "brcm,bcm4908-enet";
+         reg = <0x80002000 0x1000>;
+ 
+-        interrupts = <GIC_SPI 86 IRQ_TYPE_LEVEL_HIGH>;
+-        interrupt-names = "rx";
++        interrupts = <GIC_SPI 86 IRQ_TYPE_LEVEL_HIGH>,
++                     <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>;
++        interrupt-names = "rx", "tx";
+     };
diff --git a/target/linux/bcm4908/patches-5.4/074-v5.13-0003-net-broadcom-bcm4908_enet-support-TX-interrupt.patch b/target/linux/bcm4908/patches-5.4/074-v5.13-0003-net-broadcom-bcm4908_enet-support-TX-interrupt.patch
new file mode 100644
index 0000000000..a20be2ae8b
--- /dev/null
+++ b/target/linux/bcm4908/patches-5.4/074-v5.13-0003-net-broadcom-bcm4908_enet-support-TX-interrupt.patch
@@ -0,0 +1,300 @@
+From 12bb508bfe5a564c36864b12253db23cac83bfa1 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
+Date: Thu, 11 Mar 2021 13:35:21 +0100
+Subject: [PATCH] net: broadcom: bcm4908_enet: support TX interrupt
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+It appears that each DMA channel has its own interrupt and both rings
+can be configured (the same way) to handle interrupts.
+
+1. Make ring interrupts code generic (make it operate on given ring)
+2. Move napi to ring (so each has its own)
+3. Make IRQ handler generic (match ring against received IRQ number)
+4. Add (optional) support for TX interrupt
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/broadcom/bcm4908_enet.c | 138 ++++++++++++++-----
+ 1 file changed, 103 insertions(+), 35 deletions(-)
+
+--- a/drivers/net/ethernet/broadcom/bcm4908_enet.c
++++ b/drivers/net/ethernet/broadcom/bcm4908_enet.c
+@@ -54,6 +54,7 @@ struct bcm4908_enet_dma_ring {
+ 	int length;
+ 	u16 cfg_block;
+ 	u16 st_ram_block;
++	struct napi_struct napi;
+ 
+ 	union {
+ 		void *cpu_addr;
+@@ -67,8 +68,8 @@ struct bcm4908_enet_dma_ring {
+ struct bcm4908_enet {
+ 	struct device *dev;
+ 	struct net_device *netdev;
+-	struct napi_struct napi;
+ 	void __iomem *base;
++	int irq_tx;
+ 
+ 	struct bcm4908_enet_dma_ring tx_ring;
+ 	struct bcm4908_enet_dma_ring rx_ring;
+@@ -123,24 +124,31 @@ static void enet_umac_set(struct bcm4908
+  * Helpers
+  */
+ 
+-static void bcm4908_enet_intrs_on(struct bcm4908_enet *enet)
++static void bcm4908_enet_set_mtu(struct bcm4908_enet *enet, int mtu)
+ {
+-	enet_write(enet, ENET_DMA_CH_RX_CFG + ENET_DMA_CH_CFG_INT_MASK, ENET_DMA_INT_DEFAULTS);
++	enet_umac_write(enet, UMAC_MAX_FRAME_LEN, mtu + ENET_MAX_ETH_OVERHEAD);
+ }
+ 
+-static void bcm4908_enet_intrs_off(struct bcm4908_enet *enet)
++/***
++ * DMA ring ops
++ */
++
++static void bcm4908_enet_dma_ring_intrs_on(struct bcm4908_enet *enet,
++					   struct bcm4908_enet_dma_ring *ring)
+ {
+-	enet_write(enet, ENET_DMA_CH_RX_CFG + ENET_DMA_CH_CFG_INT_MASK, 0);
++	enet_write(enet, ring->cfg_block + ENET_DMA_CH_CFG_INT_MASK, ENET_DMA_INT_DEFAULTS);
+ }
+ 
+-static void bcm4908_enet_intrs_ack(struct bcm4908_enet *enet)
++static void bcm4908_enet_dma_ring_intrs_off(struct bcm4908_enet *enet,
++					    struct bcm4908_enet_dma_ring *ring)
+ {
+-	enet_write(enet, ENET_DMA_CH_RX_CFG + ENET_DMA_CH_CFG_INT_STAT, ENET_DMA_INT_DEFAULTS);
++	enet_write(enet, ring->cfg_block + ENET_DMA_CH_CFG_INT_MASK, 0);
+ }
+ 
+-static void bcm4908_enet_set_mtu(struct bcm4908_enet *enet, int mtu)
++static void bcm4908_enet_dma_ring_intrs_ack(struct bcm4908_enet *enet,
++					    struct bcm4908_enet_dma_ring *ring)
+ {
+-	enet_umac_write(enet, UMAC_MAX_FRAME_LEN, mtu + ENET_MAX_ETH_OVERHEAD);
++	enet_write(enet, ring->cfg_block + ENET_DMA_CH_CFG_INT_STAT, ENET_DMA_INT_DEFAULTS);
+ }
+ 
+ /***
+@@ -414,11 +422,14 @@ static void bcm4908_enet_gmac_init(struc
+ static irqreturn_t bcm4908_enet_irq_handler(int irq, void *dev_id)
+ {
+ 	struct bcm4908_enet *enet = dev_id;
++	struct bcm4908_enet_dma_ring *ring;
+ 
+-	bcm4908_enet_intrs_off(enet);
+-	bcm4908_enet_intrs_ack(enet);
++	ring = (irq == enet->irq_tx) ? &enet->tx_ring : &enet->rx_ring;
+ 
+-	napi_schedule(&enet->napi);
++	bcm4908_enet_dma_ring_intrs_off(enet, ring);
++	bcm4908_enet_dma_ring_intrs_ack(enet, ring);
++
++	napi_schedule(&ring->napi);
+ 
+ 	return IRQ_HANDLED;
+ }
+@@ -426,6 +437,8 @@ static irqreturn_t bcm4908_enet_irq_hand
+ static int bcm4908_enet_open(struct net_device *netdev)
+ {
+ 	struct bcm4908_enet *enet = netdev_priv(netdev);
++	struct bcm4908_enet_dma_ring *tx_ring = &enet->tx_ring;
++	struct bcm4908_enet_dma_ring *rx_ring = &enet->rx_ring;
+ 	struct device *dev = enet->dev;
+ 	int err;
+ 
+@@ -435,6 +448,17 @@ static int bcm4908_enet_open(struct net_
+ 		return err;
+ 	}
+ 
++	if (enet->irq_tx > 0) {
++		err = request_irq(enet->irq_tx, bcm4908_enet_irq_handler, 0,
++				  "tx", enet);
++		if (err) {
++			dev_err(dev, "Failed to request IRQ %d: %d\n",
++				enet->irq_tx, err);
++			free_irq(netdev->irq, enet);
++			return err;
++		}
++	}
++
+ 	bcm4908_enet_gmac_init(enet);
+ 	bcm4908_enet_dma_reset(enet);
+ 	bcm4908_enet_dma_init(enet);
+@@ -443,14 +467,19 @@ static int bcm4908_enet_open(struct net_
+ 
+ 	enet_set(enet, ENET_DMA_CONTROLLER_CFG, ENET_DMA_CTRL_CFG_MASTER_EN);
+ 	enet_maskset(enet, ENET_DMA_CONTROLLER_CFG, ENET_DMA_CTRL_CFG_FLOWC_CH1_EN, 0);
+-	bcm4908_enet_dma_rx_ring_enable(enet, &enet->rx_ring);
+ 
+-	napi_enable(&enet->napi);
++	if (enet->irq_tx > 0) {
++		napi_enable(&tx_ring->napi);
++		bcm4908_enet_dma_ring_intrs_ack(enet, tx_ring);
++		bcm4908_enet_dma_ring_intrs_on(enet, tx_ring);
++	}
++
++	bcm4908_enet_dma_rx_ring_enable(enet, rx_ring);
++	napi_enable(&rx_ring->napi);
+ 	netif_carrier_on(netdev);
+ 	netif_start_queue(netdev);
+-
+-	bcm4908_enet_intrs_ack(enet);
+-	bcm4908_enet_intrs_on(enet);
++	bcm4908_enet_dma_ring_intrs_ack(enet, rx_ring);
++	bcm4908_enet_dma_ring_intrs_on(enet, rx_ring);
+ 
+ 	return 0;
+ }
+@@ -458,16 +487,20 @@ static int bcm4908_enet_open(struct net_
+ static int bcm4908_enet_stop(struct net_device *netdev)
+ {
+ 	struct bcm4908_enet *enet = netdev_priv(netdev);
++	struct bcm4908_enet_dma_ring *tx_ring = &enet->tx_ring;
++	struct bcm4908_enet_dma_ring *rx_ring = &enet->rx_ring;
+ 
+ 	netif_stop_queue(netdev);
+ 	netif_carrier_off(netdev);
+-	napi_disable(&enet->napi);
++	napi_disable(&rx_ring->napi);
++	napi_disable(&tx_ring->napi);
+ 
+ 	bcm4908_enet_dma_rx_ring_disable(enet, &enet->rx_ring);
+ 	bcm4908_enet_dma_tx_ring_disable(enet, &enet->tx_ring);
+ 
+ 	bcm4908_enet_dma_uninit(enet);
+ 
++	free_irq(enet->irq_tx, enet);
+ 	free_irq(enet->netdev->irq, enet);
+ 
+ 	return 0;
+@@ -484,25 +517,19 @@ static int bcm4908_enet_start_xmit(struc
+ 	u32 tmp;
+ 
+ 	/* Free transmitted skbs */
+-	while (ring->read_idx != ring->write_idx) {
+-		buf_desc = &ring->buf_desc[ring->read_idx];
+-		if (le32_to_cpu(buf_desc->ctl) & DMA_CTL_STATUS_OWN)
+-			break;
+-		slot = &ring->slots[ring->read_idx];
+-
+-		dma_unmap_single(dev, slot->dma_addr, slot->len, DMA_TO_DEVICE);
+-		dev_kfree_skb(slot->skb);
+-		if (++ring->read_idx == ring->length)
+-			ring->read_idx = 0;
+-	}
++	if (enet->irq_tx < 0 &&
++	    !(le32_to_cpu(ring->buf_desc[ring->read_idx].ctl) & DMA_CTL_STATUS_OWN))
++		napi_schedule(&enet->tx_ring.napi);
+ 
+ 	/* Don't use the last empty buf descriptor */
+ 	if (ring->read_idx <= ring->write_idx)
+ 		free_buf_descs = ring->read_idx - ring->write_idx + ring->length;
+ 	else
+ 		free_buf_descs = ring->read_idx - ring->write_idx;
+-	if (free_buf_descs < 2)
++	if (free_buf_descs < 2) {
++		netif_stop_queue(netdev);
+ 		return NETDEV_TX_BUSY;
++	}
+ 
+ 	/* Hardware removes OWN bit after sending data */
+ 	buf_desc = &ring->buf_desc[ring->write_idx];
+@@ -539,9 +566,10 @@ static int bcm4908_enet_start_xmit(struc
+ 	return NETDEV_TX_OK;
+ }
+ 
+-static int bcm4908_enet_poll(struct napi_struct *napi, int weight)
++static int bcm4908_enet_poll_rx(struct napi_struct *napi, int weight)
+ {
+-	struct bcm4908_enet *enet = container_of(napi, struct bcm4908_enet, napi);
++	struct bcm4908_enet_dma_ring *rx_ring = container_of(napi, struct bcm4908_enet_dma_ring, napi);
++	struct bcm4908_enet *enet = container_of(rx_ring, struct bcm4908_enet, rx_ring);
+ 	struct device *dev = enet->dev;
+ 	int handled = 0;
+ 
+@@ -590,7 +618,7 @@ static int bcm4908_enet_poll(struct napi
+ 
+ 	if (handled < weight) {
+ 		napi_complete_done(napi, handled);
+-		bcm4908_enet_intrs_on(enet);
++		bcm4908_enet_dma_ring_intrs_on(enet, rx_ring);
+ 	}
+ 
+ 	/* Hardware could disable ring if it run out of descriptors */
+@@ -599,6 +627,42 @@ static int bcm4908_enet_poll(struct napi
+ 	return handled;
+ }
+ 
++static int bcm4908_enet_poll_tx(struct napi_struct *napi, int weight)
++{
++	struct bcm4908_enet_dma_ring *tx_ring = container_of(napi, struct bcm4908_enet_dma_ring, napi);
++	struct bcm4908_enet *enet = container_of(tx_ring, struct bcm4908_enet, tx_ring);
++	struct bcm4908_enet_dma_ring_bd *buf_desc;
++	struct bcm4908_enet_dma_ring_slot *slot;
++	struct device *dev = enet->dev;
++	unsigned int bytes = 0;
++	int handled = 0;
++
++	while (handled < weight && tx_ring->read_idx != tx_ring->write_idx) {
++		buf_desc = &tx_ring->buf_desc[tx_ring->read_idx];
++		if (le32_to_cpu(buf_desc->ctl) & DMA_CTL_STATUS_OWN)
++			break;
++		slot = &tx_ring->slots[tx_ring->read_idx];
++
++		dma_unmap_single(dev, slot->dma_addr, slot->len, DMA_TO_DEVICE);
++		dev_kfree_skb(slot->skb);
++		bytes += slot->len;
++		if (++tx_ring->read_idx == tx_ring->length)
++			tx_ring->read_idx = 0;
++
++		handled++;
++	}
++
++	if (handled < weight) {
++		napi_complete_done(napi, handled);
++		bcm4908_enet_dma_ring_intrs_on(enet, tx_ring);
++	}
++
++	if (netif_queue_stopped(enet->netdev))
++		netif_wake_queue(enet->netdev);
++
++	return handled;
++}
++
+ static int bcm4908_enet_change_mtu(struct net_device *netdev, int new_mtu)
+ {
+ 	struct bcm4908_enet *enet = netdev_priv(netdev);
+@@ -642,6 +706,8 @@ static int bcm4908_enet_probe(struct pla
+ 	if (netdev->irq < 0)
+ 		return netdev->irq;
+ 
++	enet->irq_tx = platform_get_irq_byname(pdev, "tx");
++
+ 	dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
+ 
+ 	err = bcm4908_enet_dma_alloc(enet);
+@@ -658,7 +724,8 @@ static int bcm4908_enet_probe(struct pla
+ 	netdev->min_mtu = ETH_ZLEN;
+ 	netdev->mtu = ETH_DATA_LEN;
+ 	netdev->max_mtu = ENET_MTU_MAX;
+-	netif_napi_add(netdev, &enet->napi, bcm4908_enet_poll, 64);
++	netif_tx_napi_add(netdev, &enet->tx_ring.napi, bcm4908_enet_poll_tx, NAPI_POLL_WEIGHT);
++	netif_napi_add(netdev, &enet->rx_ring.napi, bcm4908_enet_poll_rx, NAPI_POLL_WEIGHT);
+ 
+ 	err = register_netdev(netdev);
+ 	if (err) {
+@@ -676,7 +743,8 @@ static int bcm4908_enet_remove(struct pl
+ 	struct bcm4908_enet *enet = platform_get_drvdata(pdev);
+ 
+ 	unregister_netdev(enet->netdev);
+-	netif_napi_del(&enet->napi);
++	netif_napi_del(&enet->rx_ring.napi);
++	netif_napi_del(&enet->tx_ring.napi);
+ 	bcm4908_enet_dma_free(enet);
+ 
+ 	return 0;