diff options
author | Joel Stanley <joel@jms.id.au> | 2022-09-26 09:05:58 +0300 |
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committer | Tom Rini <trini@konsulko.com> | 2022-11-28 18:25:17 +0300 |
commit | 3167b4d72226ec4c65bc295c25893230608d2135 (patch) | |
tree | 3824fd45527f467661030c4cb53eb3fd127885c5 /drivers/net/liteeth.c | |
parent | 597e7b784dbfec29fd8d6c450bc9a3a607c4feae (diff) | |
download | u-boot-3167b4d72226ec4c65bc295c25893230608d2135.tar.xz |
liteeth: LiteX Ethernet device
LiteX is a soft system-on-chip that targets FPGAs. LiteETH is a basic
network device that is commonly used in LiteX designs.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
Diffstat (limited to 'drivers/net/liteeth.c')
-rw-r--r-- | drivers/net/liteeth.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/drivers/net/liteeth.c b/drivers/net/liteeth.c new file mode 100644 index 0000000000..84d3852723 --- /dev/null +++ b/drivers/net/liteeth.c @@ -0,0 +1,214 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * LiteX Liteeth Ethernet + * + * Copyright 2021 Joel Stanley <joel@jms.id.au>, IBM Corp. + */ + +#include <linux/litex.h> + +#include <dm.h> +#include <dm/device_compat.h> +#include <net.h> + +#define LITEETH_WRITER_SLOT 0x00 +#define LITEETH_WRITER_LENGTH 0x04 +#define LITEETH_WRITER_ERRORS 0x08 +#define LITEETH_WRITER_EV_STATUS 0x0C +#define LITEETH_WRITER_EV_PENDING 0x10 +#define LITEETH_WRITER_EV_ENABLE 0x14 +#define LITEETH_READER_START 0x18 +#define LITEETH_READER_READY 0x1C +#define LITEETH_READER_LEVEL 0x20 +#define LITEETH_READER_SLOT 0x24 +#define LITEETH_READER_LENGTH 0x28 +#define LITEETH_READER_EV_STATUS 0x2C +#define LITEETH_READER_EV_PENDING 0x30 +#define LITEETH_READER_EV_ENABLE 0x34 +#define LITEETH_PREAMBLE_CRC 0x38 +#define LITEETH_PREAMBLE_ERRORS 0x3C +#define LITEETH_CRC_ERRORS 0x40 + +struct liteeth { + struct udevice *dev; + + void __iomem *base; + u32 slot_size; + + /* Tx */ + u32 tx_slot; + u32 num_tx_slots; + void __iomem *tx_base; + + /* Rx */ + u32 rx_slot; + u32 num_rx_slots; + void __iomem *rx_base; +}; + +static int liteeth_recv(struct udevice *dev, int flags, uchar **packetp) +{ + struct liteeth *priv = dev_get_priv(dev); + u8 rx_slot; + int len; + + if (!litex_read8(priv->base + LITEETH_WRITER_EV_PENDING)) { + debug("liteeth: No packet ready\n"); + return -EAGAIN; + } + + rx_slot = litex_read8(priv->base + LITEETH_WRITER_SLOT); + len = litex_read32(priv->base + LITEETH_WRITER_LENGTH); + + debug("%s: slot %d len 0x%x\n", __func__, rx_slot, len); + + *packetp = priv->rx_base + rx_slot * priv->slot_size; + + return len; +} + +static int liteeth_free_pkt(struct udevice *dev, uchar *packet, int length) +{ + struct liteeth *priv = dev_get_priv(dev); + + litex_write8(priv->base + LITEETH_WRITER_EV_PENDING, 1); + + return 0; +} + +static int liteeth_start(struct udevice *dev) +{ + struct liteeth *priv = dev_get_priv(dev); + + /* Clear pending events */ + litex_write8(priv->base + LITEETH_WRITER_EV_PENDING, 1); + litex_write8(priv->base + LITEETH_READER_EV_PENDING, 1); + + /* Enable events */ + litex_write8(priv->base + LITEETH_WRITER_EV_ENABLE, 1); + litex_write8(priv->base + LITEETH_READER_EV_ENABLE, 1); + + return 0; +} + +static void liteeth_stop(struct udevice *dev) +{ + struct liteeth *priv = dev_get_priv(dev); + + litex_write8(priv->base + LITEETH_WRITER_EV_ENABLE, 0); + litex_write8(priv->base + LITEETH_READER_EV_ENABLE, 0); +} + +static int liteeth_send(struct udevice *dev, void *packet, int len) +{ + struct liteeth *priv = dev_get_priv(dev); + void __iomem *txbuffer; + + if (!litex_read8(priv->base + LITEETH_READER_READY)) { + printf("liteeth: reader not ready\n"); + return -EAGAIN; + } + + /* Reject oversize packets */ + if (unlikely(len > priv->slot_size)) + return -EMSGSIZE; + + txbuffer = priv->tx_base + priv->tx_slot * priv->slot_size; + memcpy_toio(txbuffer, packet, len); + litex_write8(priv->base + LITEETH_READER_SLOT, priv->tx_slot); + litex_write16(priv->base + LITEETH_READER_LENGTH, len); + litex_write8(priv->base + LITEETH_READER_START, 1); + + priv->tx_slot = (priv->tx_slot + 1) % priv->num_tx_slots; + + return 0; +} + +static void liteeth_setup_slots(struct liteeth *priv) +{ + int err; + + err = ofnode_read_u32(dev_ofnode(priv->dev), "litex,rx-slots", &priv->num_rx_slots); + if (err) { + dev_dbg(priv->dev, "unable to get litex,rx-slots, using 2\n"); + priv->num_rx_slots = 2; + } + + err = ofnode_read_u32(dev_ofnode(priv->dev), "litex,tx-slots", &priv->num_tx_slots); + if (err) { + dev_dbg(priv->dev, "unable to get litex,tx-slots, using 2\n"); + priv->num_tx_slots = 2; + } + + err = ofnode_read_u32(dev_ofnode(priv->dev), "litex,slot-size", &priv->slot_size); + if (err) { + dev_dbg(priv->dev, "unable to get litex,slot-size, using 0x800\n"); + priv->slot_size = 0x800; + } +} + +static int liteeth_remove(struct udevice *dev) +{ + liteeth_stop(dev); + + return 0; +} + +static const struct eth_ops liteeth_ops = { + .start = liteeth_start, + .stop = liteeth_stop, + .send = liteeth_send, + .recv = liteeth_recv, + .free_pkt = liteeth_free_pkt, +}; + +static int liteeth_of_to_plat(struct udevice *dev) +{ + struct eth_pdata *pdata = dev_get_plat(dev); + struct liteeth *priv = dev_get_priv(dev); + void __iomem *buf_base; + + pdata->iobase = dev_read_addr(dev); + + priv->dev = dev; + + priv->base = dev_remap_addr_name(dev, "mac"); + if (!priv->base) { + dev_err(dev, "failed to map registers\n"); + return -EINVAL; + } + + buf_base = dev_remap_addr_name(dev, "buffer"); + if (!buf_base) { + dev_err(dev, "failed to map buffer\n"); + return -EINVAL; + } + + liteeth_setup_slots(priv); + + /* Rx slots */ + priv->rx_base = buf_base; + priv->rx_slot = 0; + + /* Tx slots come after Rx slots */ + priv->tx_base = buf_base + priv->num_rx_slots * priv->slot_size; + priv->tx_slot = 0; + + return 0; +} + +static const struct udevice_id liteeth_ids[] = { + { .compatible = "litex,liteeth" }, + {} +}; + +U_BOOT_DRIVER(liteeth) = { + .name = "liteeth", + .id = UCLASS_ETH, + .of_match = liteeth_ids, + .of_to_plat = liteeth_of_to_plat, + .plat_auto = sizeof(struct eth_pdata), + .remove = liteeth_remove, + .ops = &liteeth_ops, + .priv_auto = sizeof(struct liteeth), +}; 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