openwrt/target/linux/bcm4908/patches-5.4/170-0002-net-broadcom-bcm4908enet-add-BCM4908-controller-driv.patch

843 lines
25 KiB
Diff
Raw Normal View History

From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
Date: Fri, 5 Feb 2021 21:59:51 +0100
Subject: [PATCH 2/2] net: broadcom: bcm4908enet: add BCM4908 controller driver
BCM4908 SoCs family uses Ethernel controller that includes UniMAC but
uses different DMA engine (than other controllers) and requires
different programming.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
MAINTAINERS | 9 +
drivers/net/ethernet/broadcom/Kconfig | 8 +
drivers/net/ethernet/broadcom/Makefile | 1 +
drivers/net/ethernet/broadcom/bcm4908enet.c | 676 ++++++++++++++++++++
drivers/net/ethernet/broadcom/bcm4908enet.h | 96 +++
5 files changed, 790 insertions(+)
create mode 100644 drivers/net/ethernet/broadcom/bcm4908enet.c
create mode 100644 drivers/net/ethernet/broadcom/bcm4908enet.h
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3207,6 +3207,15 @@ F: Documentation/devicetree/bindings/mip
F: arch/mips/bcm47xx/*
F: arch/mips/include/asm/mach-bcm47xx/*
+BROADCOM BCM4908 ETHERNET DRIVER
+M: Rafał Miłecki <rafal@milecki.pl>
+M: bcm-kernel-feedback-list@broadcom.com
+L: netdev@vger.kernel.org
+S: Maintained
+F: Documentation/devicetree/bindings/net/brcm,bcm4908enet.yaml
+F: drivers/net/ethernet/broadcom/bcm4908enet.*
+F: drivers/net/ethernet/broadcom/unimac.h
+
BROADCOM BCM5301X ARM ARCHITECTURE
M: Hauke Mehrtens <hauke@hauke-m.de>
M: Rafał Miłecki <zajec5@gmail.com>
--- a/drivers/net/ethernet/broadcom/Kconfig
+++ b/drivers/net/ethernet/broadcom/Kconfig
@@ -51,6 +51,14 @@ config B44_PCI
depends on B44_PCI_AUTOSELECT && B44_PCICORE_AUTOSELECT
default y
+config BCM4908ENET
+ tristate "Broadcom BCM4908 internal mac support"
+ depends on ARCH_BCM4908 || COMPILE_TEST
+ default y
+ help
+ This driver supports Ethernet controller integrated into Broadcom
+ BCM4908 family SoCs.
+
config BCM63XX_ENET
tristate "Broadcom 63xx internal mac support"
depends on BCM63XX
--- a/drivers/net/ethernet/broadcom/Makefile
+++ b/drivers/net/ethernet/broadcom/Makefile
@@ -4,6 +4,7 @@
#
obj-$(CONFIG_B44) += b44.o
+obj-$(CONFIG_BCM4908ENET) += bcm4908enet.o
obj-$(CONFIG_BCM63XX_ENET) += bcm63xx_enet.o
obj-$(CONFIG_BCMGENET) += genet/
obj-$(CONFIG_BNX2) += bnx2.o
--- /dev/null
+++ b/drivers/net/ethernet/broadcom/bcm4908enet.c
@@ -0,0 +1,676 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2021 Rafał Miłecki <rafal@milecki.pl>
+ */
+
+#include <linux/delay.h>
+#include <linux/etherdevice.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include "bcm4908enet.h"
+#include "unimac.h"
+
+#define ENET_DMA_CH_RX_CFG ENET_DMA_CH0_CFG
+#define ENET_DMA_CH_TX_CFG ENET_DMA_CH1_CFG
+#define ENET_DMA_CH_RX_STATE_RAM ENET_DMA_CH0_STATE_RAM
+#define ENET_DMA_CH_TX_STATE_RAM ENET_DMA_CH1_STATE_RAM
+
+#define ENET_TX_BDS_NUM 200
+#define ENET_RX_BDS_NUM 200
+#define ENET_RX_BDS_NUM_MAX 8192
+
+#define ENET_DMA_INT_DEFAULTS (ENET_DMA_CH_CFG_INT_DONE | \
+ ENET_DMA_CH_CFG_INT_NO_DESC | \
+ ENET_DMA_CH_CFG_INT_BUFF_DONE)
+#define ENET_DMA_MAX_BURST_LEN 8 /* in 64 bit words */
+
+#define ENET_MTU_MIN 60
+#define ENET_MTU_MAX 1500 /* Is it possible to support 2044? */
+#define ENET_MTU_MAX_EXTRA_SIZE 32 /* L2 */
+
+struct bcm4908enet_dma_ring_bd {
+ __le32 ctl;
+ __le32 addr;
+} __packed;
+
+struct bcm4908enet_dma_ring_slot {
+ struct sk_buff *skb;
+ unsigned int len;
+ dma_addr_t dma_addr;
+};
+
+struct bcm4908enet_dma_ring {
+ int is_tx;
+ int read_idx;
+ int write_idx;
+ int length;
+ u16 cfg_block;
+ u16 st_ram_block;
+
+ union {
+ void *cpu_addr;
+ struct bcm4908enet_dma_ring_bd *buf_desc;
+ };
+ dma_addr_t dma_addr;
+
+ struct bcm4908enet_dma_ring_slot *slots;
+};
+
+struct bcm4908enet {
+ struct device *dev;
+ struct net_device *netdev;
+ struct napi_struct napi;
+ void __iomem *base;
+
+ struct bcm4908enet_dma_ring tx_ring;
+ struct bcm4908enet_dma_ring rx_ring;
+};
+
+/***
+ * R/W ops
+ */
+
+static inline u32 enet_read(struct bcm4908enet *enet, u16 offset)
+{
+ return readl(enet->base + offset);
+}
+
+static inline void enet_write(struct bcm4908enet *enet, u16 offset, u32 value)
+{
+ writel(value, enet->base + offset);
+}
+
+static inline void enet_maskset(struct bcm4908enet *enet, u16 offset, u32 mask, u32 set)
+{
+ u32 val;
+
+ WARN_ON(set & ~mask);
+
+ val = enet_read(enet, offset);
+ val = (val & ~mask) | (set & mask);
+ enet_write(enet, offset, val);
+}
+
+static inline void enet_set(struct bcm4908enet *enet, u16 offset, u32 set)
+{
+ enet_maskset(enet, offset, set, set);
+}
+
+static inline u32 enet_umac_read(struct bcm4908enet *enet, u16 offset)
+{
+ return enet_read(enet, ENET_UNIMAC + offset);
+}
+
+static inline void enet_umac_write(struct bcm4908enet *enet, u16 offset, u32 value)
+{
+ enet_write(enet, ENET_UNIMAC + offset, value);
+}
+
+static inline void enet_umac_maskset(struct bcm4908enet *enet, u16 offset, u32 mask, u32 set)
+{
+ enet_maskset(enet, ENET_UNIMAC + offset, mask, set);
+}
+
+static inline void enet_umac_set(struct bcm4908enet *enet, u16 offset, u32 set)
+{
+ enet_set(enet, ENET_UNIMAC + offset, set);
+}
+
+/***
+ * Helpers
+ */
+
+static void bcm4908enet_intrs_on(struct bcm4908enet *enet)
+{
+ enet_write(enet, ENET_DMA_CH_RX_CFG + ENET_DMA_CH_CFG_INT_MASK, ENET_DMA_INT_DEFAULTS);
+}
+
+static void bcm4908enet_intrs_off(struct bcm4908enet *enet)
+{
+ enet_write(enet, ENET_DMA_CH_RX_CFG + ENET_DMA_CH_CFG_INT_MASK, 0);
+}
+
+static void bcm4908enet_intrs_ack(struct bcm4908enet *enet)
+{
+ enet_write(enet, ENET_DMA_CH_RX_CFG + ENET_DMA_CH_CFG_INT_STAT, ENET_DMA_INT_DEFAULTS);
+}
+
+/***
+ * DMA
+ */
+
+static int bcm4908_dma_alloc_buf_descs(struct bcm4908enet *enet, struct bcm4908enet_dma_ring *ring)
+{
+ int size = ring->length * sizeof(struct bcm4908enet_dma_ring_bd);
+ struct device *dev = enet->dev;
+
+ ring->cpu_addr = dma_alloc_coherent(dev, size, &ring->dma_addr, GFP_KERNEL);
+ if (!ring->cpu_addr)
+ return -ENOMEM;
+
+ if (((uintptr_t)ring->cpu_addr) & (0x40 - 1)) {
+ dev_err(dev, "Invalid DMA ring alignment\n");
+ goto err_free_buf_descs;
+ }
+
+ ring->slots = kzalloc(ring->length * sizeof(*ring->slots), GFP_KERNEL);
+ if (!ring->slots)
+ goto err_free_buf_descs;
+
+ memset(ring->cpu_addr, 0, size);
+
+ ring->read_idx = 0;
+ ring->write_idx = 0;
+
+ return 0;
+
+err_free_buf_descs:
+ dma_free_coherent(dev, size, ring->cpu_addr, ring->dma_addr);
+ return -ENOMEM;
+}
+
+static void bcm4908enet_dma_free(struct bcm4908enet *enet)
+{
+ struct bcm4908enet_dma_ring *tx_ring = &enet->tx_ring;
+ struct bcm4908enet_dma_ring *rx_ring = &enet->rx_ring;
+ struct device *dev = enet->dev;
+ int size;
+
+ size = rx_ring->length * sizeof(struct bcm4908enet_dma_ring_bd);
+ if (rx_ring->cpu_addr)
+ dma_free_coherent(dev, size, rx_ring->cpu_addr, rx_ring->dma_addr);
+ kfree(rx_ring->slots);
+
+ size = tx_ring->length * sizeof(struct bcm4908enet_dma_ring_bd);
+ if (tx_ring->cpu_addr)
+ dma_free_coherent(dev, size, tx_ring->cpu_addr, tx_ring->dma_addr);
+ kfree(tx_ring->slots);
+}
+
+static int bcm4908enet_dma_alloc(struct bcm4908enet *enet)
+{
+ struct bcm4908enet_dma_ring *tx_ring = &enet->tx_ring;
+ struct bcm4908enet_dma_ring *rx_ring = &enet->rx_ring;
+ struct device *dev = enet->dev;
+ int err;
+
+ tx_ring->length = ENET_TX_BDS_NUM;
+ tx_ring->is_tx = 1;
+ tx_ring->cfg_block = ENET_DMA_CH_TX_CFG;
+ tx_ring->st_ram_block = ENET_DMA_CH_TX_STATE_RAM;
+ err = bcm4908_dma_alloc_buf_descs(enet, tx_ring);
+ if (err) {
+ dev_err(dev, "Failed to alloc TX buf descriptors: %d\n", err);
+ return err;
+ }
+
+ rx_ring->length = ENET_RX_BDS_NUM;
+ rx_ring->is_tx = 0;
+ rx_ring->cfg_block = ENET_DMA_CH_RX_CFG;
+ rx_ring->st_ram_block = ENET_DMA_CH_RX_STATE_RAM;
+ err = bcm4908_dma_alloc_buf_descs(enet, rx_ring);
+ if (err) {
+ dev_err(dev, "Failed to alloc RX buf descriptors: %d\n", err);
+ bcm4908enet_dma_free(enet);
+ return err;
+ }
+
+ return 0;
+}
+
+static void bcm4908enet_dma_reset(struct bcm4908enet *enet)
+{
+ struct bcm4908enet_dma_ring *rings[] = { &enet->rx_ring, &enet->tx_ring };
+ int i;
+
+ /* Disable the DMA controller and channel */
+ for (i = 0; i < ARRAY_SIZE(rings); i++)
+ enet_write(enet, rings[i]->cfg_block + ENET_DMA_CH_CFG, 0);
+ enet_maskset(enet, ENET_DMA_CONTROLLER_CFG, ENET_DMA_CTRL_CFG_MASTER_EN, 0);
+
+ /* Reset channels state */
+ for (i = 0; i < ARRAY_SIZE(rings); i++) {
+ struct bcm4908enet_dma_ring *ring = rings[i];
+
+ enet_write(enet, ring->st_ram_block + ENET_DMA_CH_STATE_RAM_BASE_DESC_PTR, 0);
+ enet_write(enet, ring->st_ram_block + ENET_DMA_CH_STATE_RAM_STATE_DATA, 0);
+ enet_write(enet, ring->st_ram_block + ENET_DMA_CH_STATE_RAM_DESC_LEN_STATUS, 0);
+ enet_write(enet, ring->st_ram_block + ENET_DMA_CH_STATE_RAM_DESC_BASE_BUFPTR, 0);
+ }
+}
+
+static int bcm4908enet_dma_alloc_rx_buf(struct bcm4908enet *enet, unsigned int idx)
+{
+ struct bcm4908enet_dma_ring_bd *buf_desc = &enet->rx_ring.buf_desc[idx];
+ struct bcm4908enet_dma_ring_slot *slot = &enet->rx_ring.slots[idx];
+ struct device *dev = enet->dev;
+ u32 tmp;
+ int err;
+
+ slot->len = ENET_MTU_MAX + ENET_MTU_MAX_EXTRA_SIZE;
+
+ slot->skb = netdev_alloc_skb(enet->netdev, slot->len);
+ if (!slot->skb)
+ return -ENOMEM;
+
+ slot->dma_addr = dma_map_single(dev, slot->skb->data, slot->len, DMA_FROM_DEVICE);
+ err = dma_mapping_error(dev, slot->dma_addr);
+ if (err) {
+ dev_err(dev, "Failed to map DMA buffer: %d\n", err);
+ kfree_skb(slot->skb);
+ slot->skb = NULL;
+ return err;
+ }
+
+ tmp = slot->len << DMA_CTL_LEN_DESC_BUFLENGTH_SHIFT;
+ tmp |= DMA_CTL_STATUS_OWN;
+ if (idx == enet->rx_ring.length - 1)
+ tmp |= DMA_CTL_STATUS_WRAP;
+ buf_desc->ctl = cpu_to_le32(tmp);
+ buf_desc->addr = cpu_to_le32(slot->dma_addr);
+
+ return 0;
+}
+
+static void bcm4908enet_dma_ring_init(struct bcm4908enet *enet,
+ struct bcm4908enet_dma_ring *ring)
+{
+ int reset_channel = 0; /* We support only 1 main channel (with TX and RX) */
+ int reset_subch = ring->is_tx ? 1 : 0;
+
+ /* Reset the DMA channel */
+ enet_write(enet, ENET_DMA_CTRL_CHANNEL_RESET, BIT(reset_channel * 2 + reset_subch));
+ enet_write(enet, ENET_DMA_CTRL_CHANNEL_RESET, 0);
+
+ enet_write(enet, ring->cfg_block + ENET_DMA_CH_CFG, 0);
+ enet_write(enet, ring->cfg_block + ENET_DMA_CH_CFG_MAX_BURST, ENET_DMA_MAX_BURST_LEN);
+ enet_write(enet, ring->cfg_block + ENET_DMA_CH_CFG_INT_MASK, 0);
+
+ enet_write(enet, ring->st_ram_block + ENET_DMA_CH_STATE_RAM_BASE_DESC_PTR,
+ (uint32_t)ring->dma_addr);
+}
+
+static void bcm4908enet_dma_uninit(struct bcm4908enet *enet)
+{
+ struct bcm4908enet_dma_ring *rx_ring = &enet->rx_ring;
+ struct bcm4908enet_dma_ring_slot *slot;
+ struct device *dev = enet->dev;
+ int i;
+
+ for (i = rx_ring->length - 1; i >= 0; i--) {
+ slot = &rx_ring->slots[i];
+ if (!slot->skb)
+ continue;
+ dma_unmap_single(dev, slot->dma_addr, slot->len, DMA_FROM_DEVICE);
+ kfree_skb(slot->skb);
+ slot->skb = NULL;
+ }
+}
+
+static int bcm4908enet_dma_init(struct bcm4908enet *enet)
+{
+ struct bcm4908enet_dma_ring *rx_ring = &enet->rx_ring;
+ struct device *dev = enet->dev;
+ int err;
+ int i;
+
+ for (i = 0; i < rx_ring->length; i++) {
+ err = bcm4908enet_dma_alloc_rx_buf(enet, i);
+ if (err) {
+ dev_err(dev, "Failed to alloc RX buffer: %d\n", err);
+ bcm4908enet_dma_uninit(enet);
+ return err;
+ }
+ }
+
+ bcm4908enet_dma_ring_init(enet, &enet->tx_ring);
+ bcm4908enet_dma_ring_init(enet, &enet->rx_ring);
+
+ return 0;
+}
+
+static void bcm4908enet_dma_tx_ring_ensable(struct bcm4908enet *enet,
+ struct bcm4908enet_dma_ring *ring)
+{
+ enet_write(enet, ring->cfg_block + ENET_DMA_CH_CFG, ENET_DMA_CH_CFG_ENABLE);
+}
+
+static void bcm4908enet_dma_tx_ring_disable(struct bcm4908enet *enet,
+ struct bcm4908enet_dma_ring *ring)
+{
+ enet_write(enet, ring->cfg_block + ENET_DMA_CH_CFG, 0);
+}
+
+static void bcm4908enet_dma_rx_ring_enable(struct bcm4908enet *enet,
+ struct bcm4908enet_dma_ring *ring)
+{
+ enet_set(enet, ring->cfg_block + ENET_DMA_CH_CFG, ENET_DMA_CH_CFG_ENABLE);
+}
+
+static void bcm4908enet_dma_rx_ring_disable(struct bcm4908enet *enet,
+ struct bcm4908enet_dma_ring *ring)
+{
+ unsigned long deadline;
+ u32 tmp;
+
+ enet_maskset(enet, ring->cfg_block + ENET_DMA_CH_CFG, ENET_DMA_CH_CFG_ENABLE, 0);
+
+ deadline = jiffies + usecs_to_jiffies(2000);
+ do {
+ tmp = enet_read(enet, ring->cfg_block + ENET_DMA_CH_CFG);
+ if (!(tmp & ENET_DMA_CH_CFG_ENABLE))
+ return;
+ enet_maskset(enet, ring->cfg_block + ENET_DMA_CH_CFG, ENET_DMA_CH_CFG_ENABLE, 0);
+ usleep_range(10, 30);
+ } while (!time_after_eq(jiffies, deadline));
+
+ dev_warn(enet->dev, "Timeout waiting for DMA TX stop\n");
+}
+
+/***
+ * Ethernet driver
+ */
+
+static void bcm4908enet_gmac_init(struct bcm4908enet *enet)
+{
+ u32 cmd;
+
+ cmd = enet_umac_read(enet, UMAC_CMD);
+ enet_umac_write(enet, UMAC_CMD, cmd | CMD_SW_RESET);
+ enet_umac_write(enet, UMAC_CMD, cmd & ~CMD_SW_RESET);
+
+ enet_set(enet, ENET_FLUSH, ENET_FLUSH_RXFIFO_FLUSH | ENET_FLUSH_TXFIFO_FLUSH);
+ enet_maskset(enet, ENET_FLUSH, ENET_FLUSH_RXFIFO_FLUSH | ENET_FLUSH_TXFIFO_FLUSH, 0);
+
+ enet_set(enet, ENET_MIB_CTRL, ENET_MIB_CTRL_CLR_MIB);
+ enet_maskset(enet, ENET_MIB_CTRL, ENET_MIB_CTRL_CLR_MIB, 0);
+
+ cmd = enet_umac_read(enet, UMAC_CMD);
+ cmd &= ~(CMD_SPEED_MASK << CMD_SPEED_SHIFT);
+ cmd &= ~CMD_TX_EN;
+ cmd &= ~CMD_RX_EN;
+ cmd |= CMD_SPEED_1000 << CMD_SPEED_SHIFT;
+ enet_umac_write(enet, UMAC_CMD, cmd);
+
+ enet_maskset(enet, ENET_GMAC_STATUS,
+ ENET_GMAC_STATUS_ETH_SPEED_MASK |
+ ENET_GMAC_STATUS_HD |
+ ENET_GMAC_STATUS_AUTO_CFG_EN |
+ ENET_GMAC_STATUS_LINK_UP,
+ ENET_GMAC_STATUS_ETH_SPEED_1000 |
+ ENET_GMAC_STATUS_AUTO_CFG_EN |
+ ENET_GMAC_STATUS_LINK_UP);
+}
+
+static irqreturn_t bcm4908enet_irq_handler(int irq, void *dev_id)
+{
+ struct bcm4908enet *enet = dev_id;
+
+ bcm4908enet_intrs_off(enet);
+ bcm4908enet_intrs_ack(enet);
+
+ napi_schedule(&enet->napi);
+
+ return IRQ_HANDLED;
+}
+
+static int bcm4908enet_open(struct net_device *netdev)
+{
+ struct bcm4908enet *enet = netdev_priv(netdev);
+ struct device *dev = enet->dev;
+ int err;
+
+ err = request_irq(netdev->irq, bcm4908enet_irq_handler, 0, "enet", enet);
+ if (err) {
+ dev_err(dev, "Failed to request IRQ %d: %d\n", netdev->irq, err);
+ return err;
+ }
+
+ bcm4908enet_gmac_init(enet);
+ bcm4908enet_dma_reset(enet);
+ bcm4908enet_dma_init(enet);
+
+ enet_umac_set(enet, UMAC_CMD, CMD_TX_EN | CMD_RX_EN);
+
+ 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);
+ bcm4908enet_dma_rx_ring_enable(enet, &enet->rx_ring);
+
+ napi_enable(&enet->napi);
+ netif_carrier_on(netdev);
+ netif_start_queue(netdev);
+
+ bcm4908enet_intrs_ack(enet);
+ bcm4908enet_intrs_on(enet);
+
+ return 0;
+}
+
+static int bcm4908enet_stop(struct net_device *netdev)
+{
+ struct bcm4908enet *enet = netdev_priv(netdev);
+
+ netif_stop_queue(netdev);
+ netif_carrier_off(netdev);
+ napi_disable(&enet->napi);
+
+ bcm4908enet_dma_rx_ring_disable(enet, &enet->rx_ring);
+ bcm4908enet_dma_tx_ring_disable(enet, &enet->tx_ring);
+
+ bcm4908enet_dma_uninit(enet);
+
+ free_irq(enet->netdev->irq, enet);
+
+ return 0;
+}
+
+static int bcm4908enet_start_xmit(struct sk_buff *skb, struct net_device *netdev)
+{
+ struct bcm4908enet *enet = netdev_priv(netdev);
+ struct bcm4908enet_dma_ring *ring = &enet->tx_ring;
+ struct bcm4908enet_dma_ring_slot *slot;
+ struct device *dev = enet->dev;
+ struct bcm4908enet_dma_ring_bd *buf_desc;
+ int free_buf_descs;
+ u32 tmp;
+
+ /* Free transmitted skbs */
+ while (ring->read_idx != ring->write_idx) {
+ buf_desc = &ring->buf_desc[ring->read_idx];
+ if (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;
+ }
+
+ /* 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)
+ return NETDEV_TX_BUSY;
+
+ /* Hardware removes OWN bit after sending data */
+ buf_desc = &ring->buf_desc[ring->write_idx];
+ if (unlikely(le32_to_cpu(buf_desc->ctl) & DMA_CTL_STATUS_OWN)) {
+ netif_stop_queue(netdev);
+ return NETDEV_TX_BUSY;
+ }
+
+ slot = &ring->slots[ring->write_idx];
+ slot->skb = skb;
+ slot->len = skb->len;
+ slot->dma_addr = dma_map_single(dev, skb->data, skb->len, DMA_TO_DEVICE);
+ if (unlikely(dma_mapping_error(dev, slot->dma_addr)))
+ return NETDEV_TX_BUSY;
+
+ tmp = skb->len << DMA_CTL_LEN_DESC_BUFLENGTH_SHIFT;
+ tmp |= DMA_CTL_STATUS_OWN;
+ tmp |= DMA_CTL_STATUS_SOP;
+ tmp |= DMA_CTL_STATUS_EOP;
+ tmp |= DMA_CTL_STATUS_APPEND_CRC;
+ if (ring->write_idx + 1 == ring->length - 1)
+ tmp |= DMA_CTL_STATUS_WRAP;
+
+ buf_desc->addr = cpu_to_le32((uint32_t)slot->dma_addr);
+ buf_desc->ctl = cpu_to_le32(tmp);
+
+ bcm4908enet_dma_tx_ring_ensable(enet, &enet->tx_ring);
+
+ if (++ring->write_idx == ring->length - 1)
+ ring->write_idx = 0;
+ enet->netdev->stats.tx_bytes += skb->len;
+ enet->netdev->stats.tx_packets++;
+
+ return NETDEV_TX_OK;
+}
+
+static int bcm4908enet_poll(struct napi_struct *napi, int weight)
+{
+ struct bcm4908enet *enet = container_of(napi, struct bcm4908enet, napi);
+ struct device *dev = enet->dev;
+ int handled = 0;
+
+ while (handled < weight) {
+ struct bcm4908enet_dma_ring_bd *buf_desc;
+ struct bcm4908enet_dma_ring_slot slot;
+ u32 ctl;
+ int len;
+ int err;
+
+ buf_desc = &enet->rx_ring.buf_desc[enet->rx_ring.read_idx];
+ ctl = le32_to_cpu(buf_desc->ctl);
+ if (ctl & DMA_CTL_STATUS_OWN)
+ break;
+
+ slot = enet->rx_ring.slots[enet->rx_ring.read_idx];
+
+ /* Provide new buffer before unpinning the old one */
+ err = bcm4908enet_dma_alloc_rx_buf(enet, enet->rx_ring.read_idx);
+ if (err)
+ break;
+
+ if (++enet->rx_ring.read_idx == enet->rx_ring.length)
+ enet->rx_ring.read_idx = 0;
+
+ len = (ctl & DMA_CTL_LEN_DESC_BUFLENGTH) >> DMA_CTL_LEN_DESC_BUFLENGTH_SHIFT;
+
+ if (len < ENET_MTU_MIN ||
+ (ctl & (DMA_CTL_STATUS_SOP | DMA_CTL_STATUS_EOP)) != (DMA_CTL_STATUS_SOP | DMA_CTL_STATUS_EOP)) {
+ enet->netdev->stats.rx_dropped++;
+ break;
+ }
+
+ dma_unmap_single(dev, slot.dma_addr, slot.len, DMA_FROM_DEVICE);
+
+ skb_put(slot.skb, len - 4 + 2);
+ slot.skb->protocol = eth_type_trans(slot.skb, enet->netdev);
+ netif_receive_skb(slot.skb);
+
+ enet->netdev->stats.rx_packets++;
+ enet->netdev->stats.rx_bytes += len;
+ }
+
+ if (handled < weight) {
+ napi_complete_done(napi, handled);
+ bcm4908enet_intrs_on(enet);
+ }
+
+ return handled;
+}
+
+static const struct net_device_ops bcm96xx_netdev_ops = {
+ .ndo_open = bcm4908enet_open,
+ .ndo_stop = bcm4908enet_stop,
+ .ndo_start_xmit = bcm4908enet_start_xmit,
+ .ndo_set_mac_address = eth_mac_addr,
+};
+
+static int bcm4908enet_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct net_device *netdev;
+ struct bcm4908enet *enet;
+ int err;
+
+ netdev = devm_alloc_etherdev(dev, sizeof(*enet));
+ if (!netdev)
+ return -ENOMEM;
+
+ enet = netdev_priv(netdev);
+ enet->dev = dev;
+ enet->netdev = netdev;
+
+ enet->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(enet->base)) {
+ dev_err(dev, "Failed to map registers: %ld\n", PTR_ERR(enet->base));
+ return PTR_ERR(enet->base);
+ }
+
+ netdev->irq = platform_get_irq_byname(pdev, "rx");
+ if (netdev->irq < 0)
+ return netdev->irq;
+
+ dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
+
+ err = bcm4908enet_dma_alloc(enet);
+ if (err)
+ return err;
+
+ SET_NETDEV_DEV(netdev, &pdev->dev);
+ eth_hw_addr_random(netdev);
+ netdev->netdev_ops = &bcm96xx_netdev_ops;
+ netdev->min_mtu = ETH_ZLEN;
+ netdev->mtu = ENET_MTU_MAX;
+ netdev->max_mtu = ENET_MTU_MAX;
+ netif_napi_add(netdev, &enet->napi, bcm4908enet_poll, 64);
+
+ err = register_netdev(netdev);
+ if (err) {
+ bcm4908enet_dma_free(enet);
+ return err;
+ }
+
+ platform_set_drvdata(pdev, enet);
+
+ return 0;
+}
+
+static int bcm4908enet_remove(struct platform_device *pdev)
+{
+ struct bcm4908enet *enet = platform_get_drvdata(pdev);
+
+ unregister_netdev(enet->netdev);
+ netif_napi_del(&enet->napi);
+ bcm4908enet_dma_free(enet);
+
+ return 0;
+}
+
+static const struct of_device_id bcm4908enet_of_match[] = {
+ { .compatible = "brcm,bcm4908enet"},
+ {},
+};
+
+static struct platform_driver bcm4908enet_driver = {
+ .driver = {
+ .name = "bcm4908enet",
+ .of_match_table = bcm4908enet_of_match,
+ },
+ .probe = bcm4908enet_probe,
+ .remove = bcm4908enet_remove,
+};
+module_platform_driver(bcm4908enet_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(of, bcm4908enet_of_match);
--- /dev/null
+++ b/drivers/net/ethernet/broadcom/bcm4908enet.h
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __BCM4908ENET_H
+#define __BCM4908ENET_H
+
+#define ENET_CONTROL 0x000
+#define ENET_MIB_CTRL 0x004
+#define ENET_MIB_CTRL_CLR_MIB 0x00000001
+#define ENET_RX_ERR_MASK 0x008
+#define ENET_MIB_MAX_PKT_SIZE 0x00C
+#define ENET_MIB_MAX_PKT_SIZE_VAL 0x00003fff
+#define ENET_DIAG_OUT 0x01c
+#define ENET_ENABLE_DROP_PKT 0x020
+#define ENET_IRQ_ENABLE 0x024
+#define ENET_IRQ_ENABLE_OVFL 0x00000001
+#define ENET_GMAC_STATUS 0x028
+#define ENET_GMAC_STATUS_ETH_SPEED_MASK 0x00000003
+#define ENET_GMAC_STATUS_ETH_SPEED_10 0x00000000
+#define ENET_GMAC_STATUS_ETH_SPEED_100 0x00000001
+#define ENET_GMAC_STATUS_ETH_SPEED_1000 0x00000002
+#define ENET_GMAC_STATUS_HD 0x00000004
+#define ENET_GMAC_STATUS_AUTO_CFG_EN 0x00000008
+#define ENET_GMAC_STATUS_LINK_UP 0x00000010
+#define ENET_IRQ_STATUS 0x02c
+#define ENET_IRQ_STATUS_OVFL 0x00000001
+#define ENET_OVERFLOW_COUNTER 0x030
+#define ENET_FLUSH 0x034
+#define ENET_FLUSH_RXFIFO_FLUSH 0x00000001
+#define ENET_FLUSH_TXFIFO_FLUSH 0x00000002
+#define ENET_RSV_SELECT 0x038
+#define ENET_BP_FORCE 0x03c
+#define ENET_BP_FORCE_FORCE 0x00000001
+#define ENET_DMA_RX_OK_TO_SEND_COUNT 0x040
+#define ENET_DMA_RX_OK_TO_SEND_COUNT_VAL 0x0000000f
+#define ENET_TX_CRC_CTRL 0x044
+#define ENET_MIB 0x200
+#define ENET_UNIMAC 0x400
+#define ENET_DMA 0x800
+#define ENET_DMA_CONTROLLER_CFG 0x800
+#define ENET_DMA_CTRL_CFG_MASTER_EN 0x00000001
+#define ENET_DMA_CTRL_CFG_FLOWC_CH1_EN 0x00000002
+#define ENET_DMA_CTRL_CFG_FLOWC_CH3_EN 0x00000004
+#define ENET_DMA_FLOWCTL_CH1_THRESH_LO 0x804
+#define ENET_DMA_FLOWCTL_CH1_THRESH_HI 0x808
+#define ENET_DMA_FLOWCTL_CH1_ALLOC 0x80c
+#define ENET_DMA_FLOWCTL_CH1_ALLOC_FORCE 0x80000000
+#define ENET_DMA_FLOWCTL_CH3_THRESH_LO 0x810
+#define ENET_DMA_FLOWCTL_CH3_THRESH_HI 0x814
+#define ENET_DMA_FLOWCTL_CH3_ALLOC 0x818
+#define ENET_DMA_FLOWCTL_CH5_THRESH_LO 0x81C
+#define ENET_DMA_FLOWCTL_CH5_THRESH_HI 0x820
+#define ENET_DMA_FLOWCTL_CH5_ALLOC 0x824
+#define ENET_DMA_FLOWCTL_CH7_THRESH_LO 0x828
+#define ENET_DMA_FLOWCTL_CH7_THRESH_HI 0x82C
+#define ENET_DMA_FLOWCTL_CH7_ALLOC 0x830
+#define ENET_DMA_CTRL_CHANNEL_RESET 0x834
+#define ENET_DMA_CTRL_CHANNEL_DEBUG 0x838
+#define ENET_DMA_CTRL_GLOBAL_INTERRUPT_STATUS 0x840
+#define ENET_DMA_CTRL_GLOBAL_INTERRUPT_MASK 0x844
+#define ENET_DMA_CH0_CFG 0xa00 /* RX */
+#define ENET_DMA_CH1_CFG 0xa10 /* TX */
+#define ENET_DMA_CH0_STATE_RAM 0xc00 /* RX */
+#define ENET_DMA_CH1_STATE_RAM 0xc10 /* TX */
+
+#define ENET_DMA_CH_CFG 0x00 /* assorted configuration */
+#define ENET_DMA_CH_CFG_ENABLE 0x00000001 /* set to enable channel */
+#define ENET_DMA_CH_CFG_PKT_HALT 0x00000002 /* idle after an EOP flag is detected */
+#define ENET_DMA_CH_CFG_BURST_HALT 0x00000004 /* idle after finish current memory burst */
+#define ENET_DMA_CH_CFG_INT_STAT 0x04 /* interrupts control and status */
+#define ENET_DMA_CH_CFG_INT_MASK 0x08 /* interrupts mask */
+#define ENET_DMA_CH_CFG_INT_BUFF_DONE 0x00000001 /* buffer done */
+#define ENET_DMA_CH_CFG_INT_DONE 0x00000002 /* packet xfer complete */
+#define ENET_DMA_CH_CFG_INT_NO_DESC 0x00000004 /* no valid descriptors */
+#define ENET_DMA_CH_CFG_INT_RX_ERROR 0x00000008 /* rxdma detect client protocol error */
+#define ENET_DMA_CH_CFG_MAX_BURST 0x0c /* max burst length permitted */
+#define ENET_DMA_CH_CFG_MAX_BURST_DESCSIZE_SEL 0x00040000 /* DMA Descriptor Size Selection */
+#define ENET_DMA_CH_CFG_SIZE 0x10
+
+#define ENET_DMA_CH_STATE_RAM_BASE_DESC_PTR 0x00 /* descriptor ring start address */
+#define ENET_DMA_CH_STATE_RAM_STATE_DATA 0x04 /* state/bytes done/ring offset */
+#define ENET_DMA_CH_STATE_RAM_DESC_LEN_STATUS 0x08 /* buffer descriptor status and len */
+#define ENET_DMA_CH_STATE_RAM_DESC_BASE_BUFPTR 0x0c /* buffer descrpitor current processing */
+#define ENET_DMA_CH_STATE_RAM_SIZE 0x10
+
+#define DMA_CTL_STATUS_APPEND_CRC 0x00000100
+#define DMA_CTL_STATUS_APPEND_BRCM_TAG 0x00000200
+#define DMA_CTL_STATUS_PRIO 0x00000C00 /* Prio for Tx */
+#define DMA_CTL_STATUS_WRAP 0x00001000 /* */
+#define DMA_CTL_STATUS_SOP 0x00002000 /* first buffer in packet */
+#define DMA_CTL_STATUS_EOP 0x00004000 /* last buffer in packet */
+#define DMA_CTL_STATUS_OWN 0x00008000 /* cleared by DMA, set by SW */
+#define DMA_CTL_LEN_DESC_BUFLENGTH 0x0fff0000
+#define DMA_CTL_LEN_DESC_BUFLENGTH_SHIFT 16
+#define DMA_CTL_LEN_DESC_MULTICAST 0x40000000
+#define DMA_CTL_LEN_DESC_USEFPM 0x80000000
+
+#endif