zephyr/drivers/ethernet/eth_liteeth.c

272 lines
6.3 KiB
C

/*
* Copyright (c) 2019 Antmicro <www.antmicro.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT litex_eth0
#define LOG_MODULE_NAME eth_liteeth
#define LOG_LEVEL CONFIG_ETHERNET_LOG_LEVEL
#include <logging/log.h>
LOG_MODULE_REGISTER(LOG_MODULE_NAME);
#include <kernel.h>
#include <device.h>
#include <soc.h>
#include <stdbool.h>
#include <net/ethernet.h>
#include <net/net_if.h>
#include <net/net_pkt.h>
#include <sys/printk.h>
/* flags */
#define LITEETH_EV_TX 0x1
#define LITEETH_EV_RX 0x1
/* slots */
#define LITEETH_SLOT_BASE DT_INST_REG_ADDR_BY_NAME(0, buffers)
#define LITEETH_SLOT_RX0 ((LITEETH_SLOT_BASE) + 0x0000)
#define LITEETH_SLOT_RX1 ((LITEETH_SLOT_BASE) + 0x0800)
#define LITEETH_SLOT_TX0 ((LITEETH_SLOT_BASE) + 0x1000)
#define LITEETH_SLOT_TX1 ((LITEETH_SLOT_BASE) + 0x1800)
/* sram - rx */
#define LITEETH_RX_BASE DT_INST_REG_ADDR_BY_NAME(0, control)
#define LITEETH_RX_SLOT ((LITEETH_RX_BASE) + 0x00)
#define LITEETH_RX_LENGTH ((LITEETH_RX_BASE) + 0x04)
#define LITEETH_RX_EV_PENDING ((LITEETH_RX_BASE) + 0x28)
#define LITEETH_RX_EV_ENABLE ((LITEETH_RX_BASE) + 0x2c)
/* sram - tx */
#define LITEETH_TX_BASE ((DT_INST_REG_ADDR_BY_NAME(0, control)) + 0x30)
#define LITEETH_TX_START ((LITEETH_TX_BASE) + 0x00)
#define LITEETH_TX_READY ((LITEETH_TX_BASE) + 0x04)
#define LITEETH_TX_SLOT ((LITEETH_TX_BASE) + 0x0c)
#define LITEETH_TX_LENGTH ((LITEETH_TX_BASE) + 0x10)
#define LITEETH_TX_EV_PENDING ((LITEETH_TX_BASE) + 0x1c)
/* irq */
#define LITEETH_IRQ DT_INST_IRQN(0)
#define LITEETH_IRQ_PRIORITY CONFIG_ETH_LITEETH_0_IRQ_PRI
/* label */
#define LITEETH_LABEL DT_INST_LABEL(0)
struct eth_liteeth_dev_data {
struct net_if *iface;
u8_t mac_addr[6];
u8_t txslot;
u8_t rxslot;
u8_t *tx_buf[2];
u8_t *rx_buf[2];
};
struct eth_liteeth_config {
void (*config_func)(void);
};
static int eth_initialize(struct device *dev)
{
const struct eth_liteeth_config *config = dev->config->config_info;
config->config_func();
return 0;
}
static int eth_tx(struct device *dev, struct net_pkt *pkt)
{
int key;
u16_t len;
struct eth_liteeth_dev_data *context = dev->driver_data;
key = irq_lock();
/* get data from packet and send it */
len = net_pkt_get_len(pkt);
net_pkt_read(pkt, context->tx_buf[context->txslot], len);
sys_write8(context->txslot, LITEETH_TX_SLOT);
sys_write8(len >> 8, LITEETH_TX_LENGTH);
sys_write8(len & 0xFF, LITEETH_TX_LENGTH + 4);
/* wait for the device to be ready to transmit */
while (sys_read8(LITEETH_TX_READY) == 0) {
;
}
/* start transmitting */
sys_write8(1, LITEETH_TX_START);
/* change slot */
context->txslot = (context->txslot + 1) % 2;
irq_unlock(key);
return 0;
}
static void eth_rx(struct device *port)
{
struct net_pkt *pkt;
struct eth_liteeth_dev_data *context = port->driver_data;
unsigned int key, r;
u16_t len = 0;
key = irq_lock();
/* get frame's length */
for (int i = 0; i < 4; i++) {
len <<= 8;
len |= sys_read8(LITEETH_RX_LENGTH + i * 0x4);
}
/* which slot is the frame in */
context->rxslot = sys_read8(LITEETH_RX_SLOT);
/* obtain rx buffer */
pkt = net_pkt_rx_alloc_with_buffer(context->iface, len, AF_UNSPEC, 0,
K_NO_WAIT);
if (pkt == NULL) {
LOG_ERR("Failed to obtain RX buffer");
goto out;
}
/* copy data to buffer */
if (net_pkt_write(pkt, (void *)context->rx_buf[context->rxslot], len) != 0) {
LOG_ERR("Failed to append RX buffer to context buffer");
net_pkt_unref(pkt);
goto out;
}
/* receive data */
r = net_recv_data(context->iface, pkt);
if (r < 0) {
LOG_ERR("Failed to enqueue frame into RX queue: %d", r);
net_pkt_unref(pkt);
}
out:
irq_unlock(key);
}
static void eth_irq_handler(struct device *port)
{
/* check sram reader events (tx) */
if (sys_read8(LITEETH_TX_EV_PENDING) & LITEETH_EV_TX) {
/* TX event is not enabled nor used by this driver; ack just
* in case if some rogue TX event appeared
*/
sys_write8(LITEETH_EV_TX, LITEETH_TX_EV_PENDING);
}
/* check sram writer events (rx) */
if (sys_read8(LITEETH_RX_EV_PENDING) & LITEETH_EV_RX) {
eth_rx(port);
/* ack writer irq */
sys_write8(LITEETH_EV_RX, LITEETH_RX_EV_PENDING);
}
}
#ifdef CONFIG_ETH_LITEETH_0_RANDOM_MAC
static void generate_mac(u8_t *mac_addr)
{
u32_t entropy;
entropy = sys_rand32_get();
mac_addr[3] = entropy >> 8;
mac_addr[4] = entropy >> 16;
/* Locally administered, unicast */
mac_addr[5] = ((entropy >> 0) & 0xfc) | 0x02;
}
#endif
#ifdef CONFIG_ETH_LITEETH_0
static struct eth_liteeth_dev_data eth_data = {
.mac_addr = DT_INST_PROP(0, local_mac_address)
};
static void eth_irq_config(void);
static const struct eth_liteeth_config eth_config = {
.config_func = eth_irq_config,
};
static void eth_iface_init(struct net_if *iface)
{
struct device *port = net_if_get_device(iface);
struct eth_liteeth_dev_data *context = port->driver_data;
static bool init_done;
/* initialize only once */
if (init_done) {
return;
}
/* set interface */
context->iface = iface;
/* initialize ethernet L2 */
ethernet_init(iface);
#ifdef CONFIG_ETH_LITEETH_0_RANDOM_MAC
/* generate random MAC address */
generate_mac(context->mac_addr);
#endif
/* set MAC address */
net_if_set_link_addr(iface, context->mac_addr, sizeof(context->mac_addr),
NET_LINK_ETHERNET);
/* clear pending events */
sys_write8(LITEETH_EV_TX, LITEETH_TX_EV_PENDING);
sys_write8(LITEETH_EV_RX, LITEETH_RX_EV_PENDING);
/* setup tx slots */
context->txslot = 0;
context->tx_buf[0] = (u8_t *)LITEETH_SLOT_TX0;
context->tx_buf[1] = (u8_t *)LITEETH_SLOT_TX1;
/* setup rx slots */
context->rxslot = 0;
context->rx_buf[0] = (u8_t *)LITEETH_SLOT_RX0;
context->rx_buf[1] = (u8_t *)LITEETH_SLOT_RX1;
init_done = true;
}
static enum ethernet_hw_caps eth_caps(struct device *dev)
{
ARG_UNUSED(dev);
return ETHERNET_LINK_10BASE_T | ETHERNET_LINK_100BASE_T |
ETHERNET_LINK_1000BASE_T;
}
static const struct ethernet_api eth_api = {
.iface_api.init = eth_iface_init,
.get_capabilities = eth_caps,
.send = eth_tx
};
NET_DEVICE_INIT(eth0, LITEETH_LABEL, eth_initialize, device_pm_control_nop,
&eth_data, &eth_config, CONFIG_ETH_INIT_PRIORITY, &eth_api,
ETHERNET_L2, NET_L2_GET_CTX_TYPE(ETHERNET_L2), NET_ETH_MTU);
static void eth_irq_config(void)
{
IRQ_CONNECT(LITEETH_IRQ, LITEETH_IRQ_PRIORITY, eth_irq_handler,
DEVICE_GET(eth0), 0);
irq_enable(LITEETH_IRQ);
sys_write8(1, LITEETH_RX_EV_ENABLE);
}
#endif /* CONFIG_ETH_LITEETH_0 */