blob: 2a13c318048cc6ddc5292bb303ad84997686aa7a [file] [log] [blame]
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/* Copyright (c) 2019-2020 Marvell International Ltd. All rights reserved */
#include <linux/bitfield.h>
#include <linux/dmapool.h>
#include <linux/etherdevice.h>
#include <linux/if_vlan.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include "prestera_dsa.h"
#include "prestera.h"
#include "prestera_hw.h"
#include "prestera_rxtx.h"
#define PRESTERA_SDMA_WAIT_MUL 10
struct prestera_sdma_desc {
__le32 word1;
__le32 word2;
__le32 buff;
__le32 next;
} __packed __aligned(16);
#define PRESTERA_SDMA_BUFF_SIZE_MAX 1544
#define PRESTERA_SDMA_RX_DESC_PKT_LEN(desc) \
((le32_to_cpu((desc)->word2) >> 16) & GENMASK(13, 0))
#define PRESTERA_SDMA_RX_DESC_OWNER(desc) \
((le32_to_cpu((desc)->word1) & BIT(31)) >> 31)
#define PRESTERA_SDMA_RX_DESC_IS_RCVD(desc) \
(PRESTERA_SDMA_RX_DESC_OWNER(desc) == PRESTERA_SDMA_RX_DESC_CPU_OWN)
#define PRESTERA_SDMA_RX_DESC_CPU_OWN 0
#define PRESTERA_SDMA_RX_DESC_DMA_OWN 1
#define PRESTERA_SDMA_RX_QUEUE_NUM 8
#define PRESTERA_SDMA_RX_DESC_PER_Q 1000
#define PRESTERA_SDMA_TX_DESC_PER_Q 1000
#define PRESTERA_SDMA_TX_MAX_BURST 64
#define PRESTERA_SDMA_TX_DESC_OWNER(desc) \
((le32_to_cpu((desc)->word1) & BIT(31)) >> 31)
#define PRESTERA_SDMA_TX_DESC_CPU_OWN 0
#define PRESTERA_SDMA_TX_DESC_DMA_OWN 1U
#define PRESTERA_SDMA_TX_DESC_IS_SENT(desc) \
(PRESTERA_SDMA_TX_DESC_OWNER(desc) == PRESTERA_SDMA_TX_DESC_CPU_OWN)
#define PRESTERA_SDMA_TX_DESC_LAST BIT(20)
#define PRESTERA_SDMA_TX_DESC_FIRST BIT(21)
#define PRESTERA_SDMA_TX_DESC_CALC_CRC BIT(12)
#define PRESTERA_SDMA_TX_DESC_SINGLE \
(PRESTERA_SDMA_TX_DESC_FIRST | PRESTERA_SDMA_TX_DESC_LAST)
#define PRESTERA_SDMA_TX_DESC_INIT \
(PRESTERA_SDMA_TX_DESC_SINGLE | PRESTERA_SDMA_TX_DESC_CALC_CRC)
#define PRESTERA_SDMA_RX_INTR_MASK_REG 0x2814
#define PRESTERA_SDMA_RX_QUEUE_STATUS_REG 0x2680
#define PRESTERA_SDMA_RX_QUEUE_DESC_REG(n) (0x260C + (n) * 16)
#define PRESTERA_SDMA_TX_QUEUE_DESC_REG 0x26C0
#define PRESTERA_SDMA_TX_QUEUE_START_REG 0x2868
struct prestera_sdma_buf {
struct prestera_sdma_desc *desc;
dma_addr_t desc_dma;
struct sk_buff *skb;
dma_addr_t buf_dma;
bool is_used;
};
struct prestera_rx_ring {
struct prestera_sdma_buf *bufs;
int next_rx;
};
struct prestera_tx_ring {
struct prestera_sdma_buf *bufs;
int next_tx;
int max_burst;
int burst;
};
struct prestera_sdma {
struct prestera_rx_ring rx_ring[PRESTERA_SDMA_RX_QUEUE_NUM];
struct prestera_tx_ring tx_ring;
struct prestera_switch *sw;
struct dma_pool *desc_pool;
struct work_struct tx_work;
struct napi_struct rx_napi;
struct net_device napi_dev;
u32 map_addr;
u64 dma_mask;
/* protect SDMA with concurrrent access from multiple CPUs */
spinlock_t tx_lock;
};
struct prestera_rxtx {
struct prestera_sdma sdma;
};
static int prestera_sdma_buf_init(struct prestera_sdma *sdma,
struct prestera_sdma_buf *buf)
{
struct prestera_sdma_desc *desc;
dma_addr_t dma;
desc = dma_pool_alloc(sdma->desc_pool, GFP_DMA | GFP_KERNEL, &dma);
if (!desc)
return -ENOMEM;
buf->buf_dma = DMA_MAPPING_ERROR;
buf->desc_dma = dma;
buf->desc = desc;
buf->skb = NULL;
return 0;
}
static u32 prestera_sdma_map(struct prestera_sdma *sdma, dma_addr_t pa)
{
return sdma->map_addr + pa;
}
static void prestera_sdma_rx_desc_init(struct prestera_sdma *sdma,
struct prestera_sdma_desc *desc,
dma_addr_t buf)
{
u32 word = le32_to_cpu(desc->word2);
u32p_replace_bits(&word, PRESTERA_SDMA_BUFF_SIZE_MAX, GENMASK(15, 0));
desc->word2 = cpu_to_le32(word);
desc->buff = cpu_to_le32(prestera_sdma_map(sdma, buf));
/* make sure buffer is set before reset the descriptor */
wmb();
desc->word1 = cpu_to_le32(0xA0000000);
}
static void prestera_sdma_rx_desc_set_next(struct prestera_sdma *sdma,
struct prestera_sdma_desc *desc,
dma_addr_t next)
{
desc->next = cpu_to_le32(prestera_sdma_map(sdma, next));
}
static int prestera_sdma_rx_skb_alloc(struct prestera_sdma *sdma,
struct prestera_sdma_buf *buf)
{
struct device *dev = sdma->sw->dev->dev;
struct sk_buff *skb;
dma_addr_t dma;
skb = alloc_skb(PRESTERA_SDMA_BUFF_SIZE_MAX, GFP_DMA | GFP_ATOMIC);
if (!skb)
return -ENOMEM;
dma = dma_map_single(dev, skb->data, skb->len, DMA_FROM_DEVICE);
if (dma_mapping_error(dev, dma))
goto err_dma_map;
if (buf->skb)
dma_unmap_single(dev, buf->buf_dma, buf->skb->len,
DMA_FROM_DEVICE);
buf->buf_dma = dma;
buf->skb = skb;
return 0;
err_dma_map:
kfree_skb(skb);
return -ENOMEM;
}
static struct sk_buff *prestera_sdma_rx_skb_get(struct prestera_sdma *sdma,
struct prestera_sdma_buf *buf)
{
dma_addr_t buf_dma = buf->buf_dma;
struct sk_buff *skb = buf->skb;
u32 len = skb->len;
int err;
err = prestera_sdma_rx_skb_alloc(sdma, buf);
if (err) {
buf->buf_dma = buf_dma;
buf->skb = skb;
skb = alloc_skb(skb->len, GFP_ATOMIC);
if (skb) {
skb_put(skb, len);
skb_copy_from_linear_data(buf->skb, skb->data, len);
}
}
prestera_sdma_rx_desc_init(sdma, buf->desc, buf->buf_dma);
return skb;
}
static int prestera_rxtx_process_skb(struct prestera_sdma *sdma,
struct sk_buff *skb)
{
const struct prestera_port *port;
struct prestera_dsa dsa;
u32 hw_port, dev_id;
int err;
skb_pull(skb, ETH_HLEN);
/* ethertype field is part of the dsa header */
err = prestera_dsa_parse(&dsa, skb->data - ETH_TLEN);
if (err)
return err;
dev_id = dsa.hw_dev_num;
hw_port = dsa.port_num;
port = prestera_port_find_by_hwid(sdma->sw, dev_id, hw_port);
if (unlikely(!port)) {
dev_warn_ratelimited(prestera_dev(sdma->sw), "received pkt for non-existent port(%u, %u)\n",
dev_id, hw_port);
return -ENOENT;
}
if (unlikely(!pskb_may_pull(skb, PRESTERA_DSA_HLEN)))
return -EINVAL;
/* remove DSA tag and update checksum */
skb_pull_rcsum(skb, PRESTERA_DSA_HLEN);
memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - PRESTERA_DSA_HLEN,
ETH_ALEN * 2);
skb_push(skb, ETH_HLEN);
skb->protocol = eth_type_trans(skb, port->dev);
if (dsa.vlan.is_tagged) {
u16 tci = dsa.vlan.vid & VLAN_VID_MASK;
tci |= dsa.vlan.vpt << VLAN_PRIO_SHIFT;
if (dsa.vlan.cfi_bit)
tci |= VLAN_CFI_MASK;
__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tci);
}
return 0;
}
static int prestera_sdma_next_rx_buf_idx(int buf_idx)
{
return (buf_idx + 1) % PRESTERA_SDMA_RX_DESC_PER_Q;
}
static int prestera_sdma_rx_poll(struct napi_struct *napi, int budget)
{
int qnum = PRESTERA_SDMA_RX_QUEUE_NUM;
unsigned int rxq_done_map = 0;
struct prestera_sdma *sdma;
struct list_head rx_list;
unsigned int qmask;
int pkts_done = 0;
int q;
qnum = PRESTERA_SDMA_RX_QUEUE_NUM;
qmask = GENMASK(qnum - 1, 0);
INIT_LIST_HEAD(&rx_list);
sdma = container_of(napi, struct prestera_sdma, rx_napi);
while (pkts_done < budget && rxq_done_map != qmask) {
for (q = 0; q < qnum && pkts_done < budget; q++) {
struct prestera_rx_ring *ring = &sdma->rx_ring[q];
struct prestera_sdma_desc *desc;
struct prestera_sdma_buf *buf;
int buf_idx = ring->next_rx;
struct sk_buff *skb;
buf = &ring->bufs[buf_idx];
desc = buf->desc;
if (PRESTERA_SDMA_RX_DESC_IS_RCVD(desc)) {
rxq_done_map &= ~BIT(q);
} else {
rxq_done_map |= BIT(q);
continue;
}
pkts_done++;
__skb_trim(buf->skb, PRESTERA_SDMA_RX_DESC_PKT_LEN(desc));
skb = prestera_sdma_rx_skb_get(sdma, buf);
if (!skb)
goto rx_next_buf;
if (unlikely(prestera_rxtx_process_skb(sdma, skb)))
goto rx_next_buf;
list_add_tail(&skb->list, &rx_list);
rx_next_buf:
ring->next_rx = prestera_sdma_next_rx_buf_idx(buf_idx);
}
}
if (pkts_done < budget && napi_complete_done(napi, pkts_done))
prestera_write(sdma->sw, PRESTERA_SDMA_RX_INTR_MASK_REG,
GENMASK(9, 2));
netif_receive_skb_list(&rx_list);
return pkts_done;
}
static void prestera_sdma_rx_fini(struct prestera_sdma *sdma)
{
int qnum = PRESTERA_SDMA_RX_QUEUE_NUM;
int q, b;
/* disable all rx queues */
prestera_write(sdma->sw, PRESTERA_SDMA_RX_QUEUE_STATUS_REG,
GENMASK(15, 8));
for (q = 0; q < qnum; q++) {
struct prestera_rx_ring *ring = &sdma->rx_ring[q];
if (!ring->bufs)
break;
for (b = 0; b < PRESTERA_SDMA_RX_DESC_PER_Q; b++) {
struct prestera_sdma_buf *buf = &ring->bufs[b];
if (buf->desc_dma)
dma_pool_free(sdma->desc_pool, buf->desc,
buf->desc_dma);
if (!buf->skb)
continue;
if (buf->buf_dma != DMA_MAPPING_ERROR)
dma_unmap_single(sdma->sw->dev->dev,
buf->buf_dma, buf->skb->len,
DMA_FROM_DEVICE);
kfree_skb(buf->skb);
}
}
}
static int prestera_sdma_rx_init(struct prestera_sdma *sdma)
{
int bnum = PRESTERA_SDMA_RX_DESC_PER_Q;
int qnum = PRESTERA_SDMA_RX_QUEUE_NUM;
int err;
int q;
/* disable all rx queues */
prestera_write(sdma->sw, PRESTERA_SDMA_RX_QUEUE_STATUS_REG,
GENMASK(15, 8));
for (q = 0; q < qnum; q++) {
struct prestera_sdma_buf *head, *tail, *next, *prev;
struct prestera_rx_ring *ring = &sdma->rx_ring[q];
ring->bufs = kmalloc_array(bnum, sizeof(*head), GFP_KERNEL);
if (!ring->bufs)
return -ENOMEM;
ring->next_rx = 0;
tail = &ring->bufs[bnum - 1];
head = &ring->bufs[0];
next = head;
prev = next;
do {
err = prestera_sdma_buf_init(sdma, next);
if (err)
return err;
err = prestera_sdma_rx_skb_alloc(sdma, next);
if (err)
return err;
prestera_sdma_rx_desc_init(sdma, next->desc,
next->buf_dma);
prestera_sdma_rx_desc_set_next(sdma, prev->desc,
next->desc_dma);
prev = next;
next++;
} while (prev != tail);
/* join tail with head to make a circular list */
prestera_sdma_rx_desc_set_next(sdma, tail->desc, head->desc_dma);
prestera_write(sdma->sw, PRESTERA_SDMA_RX_QUEUE_DESC_REG(q),
prestera_sdma_map(sdma, head->desc_dma));
}
/* make sure all rx descs are filled before enabling all rx queues */
wmb();
prestera_write(sdma->sw, PRESTERA_SDMA_RX_QUEUE_STATUS_REG,
GENMASK(7, 0));
return 0;
}
static void prestera_sdma_tx_desc_init(struct prestera_sdma *sdma,
struct prestera_sdma_desc *desc)
{
desc->word1 = cpu_to_le32(PRESTERA_SDMA_TX_DESC_INIT);
desc->word2 = 0;
}
static void prestera_sdma_tx_desc_set_next(struct prestera_sdma *sdma,
struct prestera_sdma_desc *desc,
dma_addr_t next)
{
desc->next = cpu_to_le32(prestera_sdma_map(sdma, next));
}
static void prestera_sdma_tx_desc_set_buf(struct prestera_sdma *sdma,
struct prestera_sdma_desc *desc,
dma_addr_t buf, size_t len)
{
u32 word = le32_to_cpu(desc->word2);
u32p_replace_bits(&word, len + ETH_FCS_LEN, GENMASK(30, 16));
desc->buff = cpu_to_le32(prestera_sdma_map(sdma, buf));
desc->word2 = cpu_to_le32(word);
}
static void prestera_sdma_tx_desc_xmit(struct prestera_sdma_desc *desc)
{
u32 word = le32_to_cpu(desc->word1);
word |= PRESTERA_SDMA_TX_DESC_DMA_OWN << 31;
/* make sure everything is written before enable xmit */
wmb();
desc->word1 = cpu_to_le32(word);
}
static int prestera_sdma_tx_buf_map(struct prestera_sdma *sdma,
struct prestera_sdma_buf *buf,
struct sk_buff *skb)
{
struct device *dma_dev = sdma->sw->dev->dev;
dma_addr_t dma;
dma = dma_map_single(dma_dev, skb->data, skb->len, DMA_TO_DEVICE);
if (dma_mapping_error(dma_dev, dma))
return -ENOMEM;
buf->buf_dma = dma;
buf->skb = skb;
return 0;
}
static void prestera_sdma_tx_buf_unmap(struct prestera_sdma *sdma,
struct prestera_sdma_buf *buf)
{
struct device *dma_dev = sdma->sw->dev->dev;
dma_unmap_single(dma_dev, buf->buf_dma, buf->skb->len, DMA_TO_DEVICE);
}
static void prestera_sdma_tx_recycle_work_fn(struct work_struct *work)
{
int bnum = PRESTERA_SDMA_TX_DESC_PER_Q;
struct prestera_tx_ring *tx_ring;
struct prestera_sdma *sdma;
int b;
sdma = container_of(work, struct prestera_sdma, tx_work);
tx_ring = &sdma->tx_ring;
for (b = 0; b < bnum; b++) {
struct prestera_sdma_buf *buf = &tx_ring->bufs[b];
if (!buf->is_used)
continue;
if (!PRESTERA_SDMA_TX_DESC_IS_SENT(buf->desc))
continue;
prestera_sdma_tx_buf_unmap(sdma, buf);
dev_consume_skb_any(buf->skb);
buf->skb = NULL;
/* make sure everything is cleaned up */
wmb();
buf->is_used = false;
}
}
static int prestera_sdma_tx_init(struct prestera_sdma *sdma)
{
struct prestera_sdma_buf *head, *tail, *next, *prev;
struct prestera_tx_ring *tx_ring = &sdma->tx_ring;
int bnum = PRESTERA_SDMA_TX_DESC_PER_Q;
int err;
INIT_WORK(&sdma->tx_work, prestera_sdma_tx_recycle_work_fn);
spin_lock_init(&sdma->tx_lock);
tx_ring->bufs = kmalloc_array(bnum, sizeof(*head), GFP_KERNEL);
if (!tx_ring->bufs)
return -ENOMEM;
tail = &tx_ring->bufs[bnum - 1];
head = &tx_ring->bufs[0];
next = head;
prev = next;
tx_ring->max_burst = PRESTERA_SDMA_TX_MAX_BURST;
tx_ring->burst = tx_ring->max_burst;
tx_ring->next_tx = 0;
do {
err = prestera_sdma_buf_init(sdma, next);
if (err)
return err;
next->is_used = false;
prestera_sdma_tx_desc_init(sdma, next->desc);
prestera_sdma_tx_desc_set_next(sdma, prev->desc,
next->desc_dma);
prev = next;
next++;
} while (prev != tail);
/* join tail with head to make a circular list */
prestera_sdma_tx_desc_set_next(sdma, tail->desc, head->desc_dma);
/* make sure descriptors are written */
wmb();
prestera_write(sdma->sw, PRESTERA_SDMA_TX_QUEUE_DESC_REG,
prestera_sdma_map(sdma, head->desc_dma));
return 0;
}
static void prestera_sdma_tx_fini(struct prestera_sdma *sdma)
{
struct prestera_tx_ring *ring = &sdma->tx_ring;
int bnum = PRESTERA_SDMA_TX_DESC_PER_Q;
int b;
cancel_work_sync(&sdma->tx_work);
if (!ring->bufs)
return;
for (b = 0; b < bnum; b++) {
struct prestera_sdma_buf *buf = &ring->bufs[b];
if (buf->desc)
dma_pool_free(sdma->desc_pool, buf->desc,
buf->desc_dma);
if (!buf->skb)
continue;
dma_unmap_single(sdma->sw->dev->dev, buf->buf_dma,
buf->skb->len, DMA_TO_DEVICE);
dev_consume_skb_any(buf->skb);
}
}
static void prestera_rxtx_handle_event(struct prestera_switch *sw,
struct prestera_event *evt,
void *arg)
{
struct prestera_sdma *sdma = arg;
if (evt->id != PRESTERA_RXTX_EVENT_RCV_PKT)
return;
prestera_write(sdma->sw, PRESTERA_SDMA_RX_INTR_MASK_REG, 0);
napi_schedule(&sdma->rx_napi);
}
static int prestera_sdma_switch_init(struct prestera_switch *sw)
{
struct prestera_sdma *sdma = &sw->rxtx->sdma;
struct device *dev = sw->dev->dev;
struct prestera_rxtx_params p;
int err;
p.use_sdma = true;
err = prestera_hw_rxtx_init(sw, &p);
if (err) {
dev_err(dev, "failed to init rxtx by hw\n");
return err;
}
sdma->dma_mask = dma_get_mask(dev);
sdma->map_addr = p.map_addr;
sdma->sw = sw;
sdma->desc_pool = dma_pool_create("desc_pool", dev,
sizeof(struct prestera_sdma_desc),
16, 0);
if (!sdma->desc_pool)
return -ENOMEM;
err = prestera_sdma_rx_init(sdma);
if (err) {
dev_err(dev, "failed to init rx ring\n");
goto err_rx_init;
}
err = prestera_sdma_tx_init(sdma);
if (err) {
dev_err(dev, "failed to init tx ring\n");
goto err_tx_init;
}
err = prestera_hw_event_handler_register(sw, PRESTERA_EVENT_TYPE_RXTX,
prestera_rxtx_handle_event,
sdma);
if (err)
goto err_evt_register;
init_dummy_netdev(&sdma->napi_dev);
netif_napi_add(&sdma->napi_dev, &sdma->rx_napi, prestera_sdma_rx_poll, 64);
napi_enable(&sdma->rx_napi);
return 0;
err_evt_register:
err_tx_init:
prestera_sdma_tx_fini(sdma);
err_rx_init:
prestera_sdma_rx_fini(sdma);
dma_pool_destroy(sdma->desc_pool);
return err;
}
static void prestera_sdma_switch_fini(struct prestera_switch *sw)
{
struct prestera_sdma *sdma = &sw->rxtx->sdma;
napi_disable(&sdma->rx_napi);
netif_napi_del(&sdma->rx_napi);
prestera_hw_event_handler_unregister(sw, PRESTERA_EVENT_TYPE_RXTX,
prestera_rxtx_handle_event);
prestera_sdma_tx_fini(sdma);
prestera_sdma_rx_fini(sdma);
dma_pool_destroy(sdma->desc_pool);
}
static bool prestera_sdma_is_ready(struct prestera_sdma *sdma)
{
return !(prestera_read(sdma->sw, PRESTERA_SDMA_TX_QUEUE_START_REG) & 1);
}
static int prestera_sdma_tx_wait(struct prestera_sdma *sdma,
struct prestera_tx_ring *tx_ring)
{
int tx_wait_num = PRESTERA_SDMA_WAIT_MUL * tx_ring->max_burst;
do {
if (prestera_sdma_is_ready(sdma))
return 0;
udelay(1);
} while (--tx_wait_num);
return -EBUSY;
}
static void prestera_sdma_tx_start(struct prestera_sdma *sdma)
{
prestera_write(sdma->sw, PRESTERA_SDMA_TX_QUEUE_START_REG, 1);
schedule_work(&sdma->tx_work);
}
static netdev_tx_t prestera_sdma_xmit(struct prestera_sdma *sdma,
struct sk_buff *skb)
{
struct device *dma_dev = sdma->sw->dev->dev;
struct net_device *dev = skb->dev;
struct prestera_tx_ring *tx_ring;
struct prestera_sdma_buf *buf;
int err;
spin_lock(&sdma->tx_lock);
tx_ring = &sdma->tx_ring;
buf = &tx_ring->bufs[tx_ring->next_tx];
if (buf->is_used) {
schedule_work(&sdma->tx_work);
goto drop_skb;
}
if (unlikely(eth_skb_pad(skb)))
goto drop_skb_nofree;
err = prestera_sdma_tx_buf_map(sdma, buf, skb);
if (err)
goto drop_skb;
prestera_sdma_tx_desc_set_buf(sdma, buf->desc, buf->buf_dma, skb->len);
dma_sync_single_for_device(dma_dev, buf->buf_dma, skb->len,
DMA_TO_DEVICE);
if (tx_ring->burst) {
tx_ring->burst--;
} else {
tx_ring->burst = tx_ring->max_burst;
err = prestera_sdma_tx_wait(sdma, tx_ring);
if (err)
goto drop_skb_unmap;
}
tx_ring->next_tx = (tx_ring->next_tx + 1) % PRESTERA_SDMA_TX_DESC_PER_Q;
prestera_sdma_tx_desc_xmit(buf->desc);
buf->is_used = true;
prestera_sdma_tx_start(sdma);
goto tx_done;
drop_skb_unmap:
prestera_sdma_tx_buf_unmap(sdma, buf);
drop_skb:
dev_consume_skb_any(skb);
drop_skb_nofree:
dev->stats.tx_dropped++;
tx_done:
spin_unlock(&sdma->tx_lock);
return NETDEV_TX_OK;
}
int prestera_rxtx_switch_init(struct prestera_switch *sw)
{
struct prestera_rxtx *rxtx;
rxtx = kzalloc(sizeof(*rxtx), GFP_KERNEL);
if (!rxtx)
return -ENOMEM;
sw->rxtx = rxtx;
return prestera_sdma_switch_init(sw);
}
void prestera_rxtx_switch_fini(struct prestera_switch *sw)
{
prestera_sdma_switch_fini(sw);
kfree(sw->rxtx);
}
int prestera_rxtx_port_init(struct prestera_port *port)
{
int err;
err = prestera_hw_rxtx_port_init(port);
if (err)
return err;
port->dev->needed_headroom = PRESTERA_DSA_HLEN;
return 0;
}
netdev_tx_t prestera_rxtx_xmit(struct prestera_port *port, struct sk_buff *skb)
{
struct prestera_dsa dsa;
dsa.hw_dev_num = port->dev_id;
dsa.port_num = port->hw_id;
if (skb_cow_head(skb, PRESTERA_DSA_HLEN) < 0)
return NET_XMIT_DROP;
skb_push(skb, PRESTERA_DSA_HLEN);
memmove(skb->data, skb->data + PRESTERA_DSA_HLEN, 2 * ETH_ALEN);
if (prestera_dsa_build(&dsa, skb->data + 2 * ETH_ALEN) != 0)
return NET_XMIT_DROP;
return prestera_sdma_xmit(&port->sw->rxtx->sdma, skb);
}