diff options
Diffstat (limited to 'drivers/net/ethernet/ezchip/nps_enet.c')
-rw-r--r-- | drivers/net/ethernet/ezchip/nps_enet.c | 658 |
1 files changed, 658 insertions, 0 deletions
diff --git a/drivers/net/ethernet/ezchip/nps_enet.c b/drivers/net/ethernet/ezchip/nps_enet.c new file mode 100644 index 000000000000..24a85b292007 --- /dev/null +++ b/drivers/net/ethernet/ezchip/nps_enet.c @@ -0,0 +1,658 @@ +/* + * Copyright(c) 2015 EZchip Technologies. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * The full GNU General Public License is included in this distribution in + * the file called "COPYING". + */ + +#include <linux/module.h> +#include <linux/etherdevice.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_net.h> +#include <linux/of_platform.h> +#include "nps_enet.h" + +#define DRV_NAME "nps_mgt_enet" + +static void nps_enet_clean_rx_fifo(struct net_device *ndev, u32 frame_len) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + u32 i, len = DIV_ROUND_UP(frame_len, sizeof(u32)); + + /* Empty Rx FIFO buffer by reading all words */ + for (i = 0; i < len; i++) + nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF); +} + +static void nps_enet_read_rx_fifo(struct net_device *ndev, + unsigned char *dst, u32 length) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + s32 i, last = length & (sizeof(u32) - 1); + u32 *reg = (u32 *)dst, len = length / sizeof(u32); + bool dst_is_aligned = IS_ALIGNED((unsigned long)dst, sizeof(u32)); + + /* In case dst is not aligned we need an intermediate buffer */ + if (dst_is_aligned) + for (i = 0; i < len; i++, reg++) + *reg = nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF); + else { /* !dst_is_aligned */ + for (i = 0; i < len; i++, reg++) { + u32 buf = + nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF); + + /* to accommodate word-unaligned address of "reg" + * we have to do memcpy_toio() instead of simple "=". + */ + memcpy_toio((void __iomem *)reg, &buf, sizeof(buf)); + } + } + + /* copy last bytes (if any) */ + if (last) { + u32 buf = nps_enet_reg_get(priv, NPS_ENET_REG_RX_BUF); + + memcpy_toio((void __iomem *)reg, &buf, last); + } +} + +static u32 nps_enet_rx_handler(struct net_device *ndev) +{ + u32 frame_len, err = 0; + u32 work_done = 0; + struct nps_enet_priv *priv = netdev_priv(ndev); + struct sk_buff *skb; + struct nps_enet_rx_ctl rx_ctrl; + + rx_ctrl.value = nps_enet_reg_get(priv, NPS_ENET_REG_RX_CTL); + frame_len = rx_ctrl.nr; + + /* Check if we got RX */ + if (!rx_ctrl.cr) + return work_done; + + /* If we got here there is a work for us */ + work_done++; + + /* Check Rx error */ + if (rx_ctrl.er) { + ndev->stats.rx_errors++; + err = 1; + } + + /* Check Rx CRC error */ + if (rx_ctrl.crc) { + ndev->stats.rx_crc_errors++; + ndev->stats.rx_dropped++; + err = 1; + } + + /* Check Frame length Min 64b */ + if (unlikely(frame_len < ETH_ZLEN)) { + ndev->stats.rx_length_errors++; + ndev->stats.rx_dropped++; + err = 1; + } + + if (err) + goto rx_irq_clean; + + /* Skb allocation */ + skb = netdev_alloc_skb_ip_align(ndev, frame_len); + if (unlikely(!skb)) { + ndev->stats.rx_errors++; + ndev->stats.rx_dropped++; + goto rx_irq_clean; + } + + /* Copy frame from Rx fifo into the skb */ + nps_enet_read_rx_fifo(ndev, skb->data, frame_len); + + skb_put(skb, frame_len); + skb->protocol = eth_type_trans(skb, ndev); + skb->ip_summed = CHECKSUM_UNNECESSARY; + + ndev->stats.rx_packets++; + ndev->stats.rx_bytes += frame_len; + netif_receive_skb(skb); + + goto rx_irq_frame_done; + +rx_irq_clean: + /* Clean Rx fifo */ + nps_enet_clean_rx_fifo(ndev, frame_len); + +rx_irq_frame_done: + /* Ack Rx ctrl register */ + nps_enet_reg_set(priv, NPS_ENET_REG_RX_CTL, 0); + + return work_done; +} + +static void nps_enet_tx_handler(struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + struct nps_enet_tx_ctl tx_ctrl; + + tx_ctrl.value = nps_enet_reg_get(priv, NPS_ENET_REG_TX_CTL); + + /* Check if we got TX */ + if (!priv->tx_packet_sent || tx_ctrl.ct) + return; + + /* Check Tx transmit error */ + if (unlikely(tx_ctrl.et)) { + ndev->stats.tx_errors++; + } else { + ndev->stats.tx_packets++; + ndev->stats.tx_bytes += tx_ctrl.nt; + } + + if (priv->tx_skb) { + dev_kfree_skb(priv->tx_skb); + priv->tx_skb = NULL; + } + + priv->tx_packet_sent = false; + + if (netif_queue_stopped(ndev)) + netif_wake_queue(ndev); +} + +/** + * nps_enet_poll - NAPI poll handler. + * @napi: Pointer to napi_struct structure. + * @budget: How many frames to process on one call. + * + * returns: Number of processed frames + */ +static int nps_enet_poll(struct napi_struct *napi, int budget) +{ + struct net_device *ndev = napi->dev; + struct nps_enet_priv *priv = netdev_priv(ndev); + struct nps_enet_buf_int_enable buf_int_enable; + u32 work_done; + + buf_int_enable.rx_rdy = NPS_ENET_ENABLE; + buf_int_enable.tx_done = NPS_ENET_ENABLE; + nps_enet_tx_handler(ndev); + work_done = nps_enet_rx_handler(ndev); + if (work_done < budget) { + napi_complete(napi); + nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, + buf_int_enable.value); + } + + return work_done; +} + +/** + * nps_enet_irq_handler - Global interrupt handler for ENET. + * @irq: irq number. + * @dev_instance: device instance. + * + * returns: IRQ_HANDLED for all cases. + * + * EZchip ENET has 2 interrupt causes, and depending on bits raised in + * CTRL registers we may tell what is a reason for interrupt to fire up. + * We got one for RX and the other for TX (completion). + */ +static irqreturn_t nps_enet_irq_handler(s32 irq, void *dev_instance) +{ + struct net_device *ndev = dev_instance; + struct nps_enet_priv *priv = netdev_priv(ndev); + struct nps_enet_buf_int_cause buf_int_cause; + + buf_int_cause.value = + nps_enet_reg_get(priv, NPS_ENET_REG_BUF_INT_CAUSE); + + if (buf_int_cause.tx_done || buf_int_cause.rx_rdy) + if (likely(napi_schedule_prep(&priv->napi))) { + nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, 0); + __napi_schedule(&priv->napi); + } + + return IRQ_HANDLED; +} + +static void nps_enet_set_hw_mac_address(struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + struct nps_enet_ge_mac_cfg_1 ge_mac_cfg_1; + struct nps_enet_ge_mac_cfg_2 *ge_mac_cfg_2 = &priv->ge_mac_cfg_2; + + /* set MAC address in HW */ + ge_mac_cfg_1.octet_0 = ndev->dev_addr[0]; + ge_mac_cfg_1.octet_1 = ndev->dev_addr[1]; + ge_mac_cfg_1.octet_2 = ndev->dev_addr[2]; + ge_mac_cfg_1.octet_3 = ndev->dev_addr[3]; + ge_mac_cfg_2->octet_4 = ndev->dev_addr[4]; + ge_mac_cfg_2->octet_5 = ndev->dev_addr[5]; + + nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_1, + ge_mac_cfg_1.value); + + nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2, + ge_mac_cfg_2->value); +} + +/** + * nps_enet_hw_reset - Reset the network device. + * @ndev: Pointer to the network device. + * + * This function reset the PCS and TX fifo. + * The programming model is to set the relevant reset bits + * wait for some time for this to propagate and then unset + * the reset bits. This way we ensure that reset procedure + * is done successfully by device. + */ +static void nps_enet_hw_reset(struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + struct nps_enet_ge_rst ge_rst; + struct nps_enet_phase_fifo_ctl phase_fifo_ctl; + + ge_rst.value = 0; + phase_fifo_ctl.value = 0; + /* Pcs reset sequence*/ + ge_rst.gmac_0 = NPS_ENET_ENABLE; + nps_enet_reg_set(priv, NPS_ENET_REG_GE_RST, ge_rst.value); + usleep_range(10, 20); + ge_rst.value = 0; + nps_enet_reg_set(priv, NPS_ENET_REG_GE_RST, ge_rst.value); + + /* Tx fifo reset sequence */ + phase_fifo_ctl.rst = NPS_ENET_ENABLE; + phase_fifo_ctl.init = NPS_ENET_ENABLE; + nps_enet_reg_set(priv, NPS_ENET_REG_PHASE_FIFO_CTL, + phase_fifo_ctl.value); + usleep_range(10, 20); + phase_fifo_ctl.value = 0; + nps_enet_reg_set(priv, NPS_ENET_REG_PHASE_FIFO_CTL, + phase_fifo_ctl.value); +} + +static void nps_enet_hw_enable_control(struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + struct nps_enet_ge_mac_cfg_0 ge_mac_cfg_0; + struct nps_enet_buf_int_enable buf_int_enable; + struct nps_enet_ge_mac_cfg_2 *ge_mac_cfg_2 = &priv->ge_mac_cfg_2; + struct nps_enet_ge_mac_cfg_3 *ge_mac_cfg_3 = &priv->ge_mac_cfg_3; + s32 max_frame_length; + + ge_mac_cfg_0.value = 0; + buf_int_enable.value = 0; + /* Enable Rx and Tx statistics */ + ge_mac_cfg_2->stat_en = NPS_ENET_GE_MAC_CFG_2_STAT_EN; + + /* Discard packets with different MAC address */ + ge_mac_cfg_2->disc_da = NPS_ENET_ENABLE; + + /* Discard multicast packets */ + ge_mac_cfg_2->disc_mc = NPS_ENET_ENABLE; + + nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2, + ge_mac_cfg_2->value); + + /* Discard Packets bigger than max frame length */ + max_frame_length = ETH_HLEN + ndev->mtu + ETH_FCS_LEN; + if (max_frame_length <= NPS_ENET_MAX_FRAME_LENGTH) { + ge_mac_cfg_3->max_len = max_frame_length; + nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_3, + ge_mac_cfg_3->value); + } + + /* Enable interrupts */ + buf_int_enable.rx_rdy = NPS_ENET_ENABLE; + buf_int_enable.tx_done = NPS_ENET_ENABLE; + nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, + buf_int_enable.value); + + /* Write device MAC address to HW */ + nps_enet_set_hw_mac_address(ndev); + + /* Rx and Tx HW features */ + ge_mac_cfg_0.tx_pad_en = NPS_ENET_ENABLE; + ge_mac_cfg_0.tx_crc_en = NPS_ENET_ENABLE; + ge_mac_cfg_0.rx_crc_strip = NPS_ENET_ENABLE; + + /* IFG configuration */ + ge_mac_cfg_0.rx_ifg = NPS_ENET_GE_MAC_CFG_0_RX_IFG; + ge_mac_cfg_0.tx_ifg = NPS_ENET_GE_MAC_CFG_0_TX_IFG; + + /* preamble configuration */ + ge_mac_cfg_0.rx_pr_check_en = NPS_ENET_ENABLE; + ge_mac_cfg_0.tx_pr_len = NPS_ENET_GE_MAC_CFG_0_TX_PR_LEN; + + /* enable flow control frames */ + ge_mac_cfg_0.tx_fc_en = NPS_ENET_ENABLE; + ge_mac_cfg_0.rx_fc_en = NPS_ENET_ENABLE; + ge_mac_cfg_0.tx_fc_retr = NPS_ENET_GE_MAC_CFG_0_TX_FC_RETR; + + /* Enable Rx and Tx */ + ge_mac_cfg_0.rx_en = NPS_ENET_ENABLE; + ge_mac_cfg_0.tx_en = NPS_ENET_ENABLE; + + nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_0, + ge_mac_cfg_0.value); +} + +static void nps_enet_hw_disable_control(struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + + /* Disable interrupts */ + nps_enet_reg_set(priv, NPS_ENET_REG_BUF_INT_ENABLE, 0); + + /* Disable Rx and Tx */ + nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_0, 0); +} + +static void nps_enet_send_frame(struct net_device *ndev, + struct sk_buff *skb) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + struct nps_enet_tx_ctl tx_ctrl; + short length = skb->len; + u32 i, len = DIV_ROUND_UP(length, sizeof(u32)); + u32 *src = (u32 *)virt_to_phys(skb->data); + bool src_is_aligned = IS_ALIGNED((unsigned long)src, sizeof(u32)); + + tx_ctrl.value = 0; + /* In case src is not aligned we need an intermediate buffer */ + if (src_is_aligned) + for (i = 0; i < len; i++, src++) + nps_enet_reg_set(priv, NPS_ENET_REG_TX_BUF, *src); + else { /* !src_is_aligned */ + for (i = 0; i < len; i++, src++) { + u32 buf; + + /* to accommodate word-unaligned address of "src" + * we have to do memcpy_fromio() instead of simple "=" + */ + memcpy_fromio(&buf, (void __iomem *)src, sizeof(buf)); + nps_enet_reg_set(priv, NPS_ENET_REG_TX_BUF, buf); + } + } + /* Write the length of the Frame */ + tx_ctrl.nt = length; + + /* Indicate SW is done */ + priv->tx_packet_sent = true; + tx_ctrl.ct = NPS_ENET_ENABLE; + + /* Send Frame */ + nps_enet_reg_set(priv, NPS_ENET_REG_TX_CTL, tx_ctrl.value); +} + +/** + * nps_enet_set_mac_address - Set the MAC address for this device. + * @ndev: Pointer to net_device structure. + * @p: 6 byte Address to be written as MAC address. + * + * This function copies the HW address from the sockaddr structure to the + * net_device structure and updates the address in HW. + * + * returns: -EBUSY if the net device is busy or 0 if the address is set + * successfully. + */ +static s32 nps_enet_set_mac_address(struct net_device *ndev, void *p) +{ + struct sockaddr *addr = p; + s32 res; + + if (netif_running(ndev)) + return -EBUSY; + + res = eth_mac_addr(ndev, p); + if (!res) { + ether_addr_copy(ndev->dev_addr, addr->sa_data); + nps_enet_set_hw_mac_address(ndev); + } + + return res; +} + +/** + * nps_enet_set_rx_mode - Change the receive filtering mode. + * @ndev: Pointer to the network device. + * + * This function enables/disables promiscuous mode + */ +static void nps_enet_set_rx_mode(struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + struct nps_enet_ge_mac_cfg_2 ge_mac_cfg_2; + + ge_mac_cfg_2.value = priv->ge_mac_cfg_2.value; + + if (ndev->flags & IFF_PROMISC) { + ge_mac_cfg_2.disc_da = NPS_ENET_DISABLE; + ge_mac_cfg_2.disc_mc = NPS_ENET_DISABLE; + } else { + ge_mac_cfg_2.disc_da = NPS_ENET_ENABLE; + ge_mac_cfg_2.disc_mc = NPS_ENET_ENABLE; + } + + nps_enet_reg_set(priv, NPS_ENET_REG_GE_MAC_CFG_2, ge_mac_cfg_2.value); +} + +/** + * nps_enet_open - Open the network device. + * @ndev: Pointer to the network device. + * + * returns: 0, on success or non-zero error value on failure. + * + * This function sets the MAC address, requests and enables an IRQ + * for the ENET device and starts the Tx queue. + */ +static s32 nps_enet_open(struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + s32 err; + + /* Reset private variables */ + priv->tx_packet_sent = false; + priv->ge_mac_cfg_2.value = 0; + priv->ge_mac_cfg_3.value = 0; + + /* ge_mac_cfg_3 default values */ + priv->ge_mac_cfg_3.rx_ifg_th = NPS_ENET_GE_MAC_CFG_3_RX_IFG_TH; + priv->ge_mac_cfg_3.max_len = NPS_ENET_GE_MAC_CFG_3_MAX_LEN; + + /* Disable HW device */ + nps_enet_hw_disable_control(ndev); + + /* irq Rx allocation */ + err = request_irq(priv->irq, nps_enet_irq_handler, + 0, "enet-rx-tx", ndev); + if (err) + return err; + + napi_enable(&priv->napi); + + /* Enable HW device */ + nps_enet_hw_reset(ndev); + nps_enet_hw_enable_control(ndev); + + netif_start_queue(ndev); + + return 0; +} + +/** + * nps_enet_stop - Close the network device. + * @ndev: Pointer to the network device. + * + * This function stops the Tx queue, disables interrupts for the ENET device. + */ +static s32 nps_enet_stop(struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + + napi_disable(&priv->napi); + netif_stop_queue(ndev); + nps_enet_hw_disable_control(ndev); + free_irq(priv->irq, ndev); + + return 0; +} + +/** + * nps_enet_start_xmit - Starts the data transmission. + * @skb: sk_buff pointer that contains data to be Transmitted. + * @ndev: Pointer to net_device structure. + * + * returns: NETDEV_TX_OK, on success + * NETDEV_TX_BUSY, if any of the descriptors are not free. + * + * This function is invoked from upper layers to initiate transmission. + */ +static netdev_tx_t nps_enet_start_xmit(struct sk_buff *skb, + struct net_device *ndev) +{ + struct nps_enet_priv *priv = netdev_priv(ndev); + + /* This driver handles one frame at a time */ + netif_stop_queue(ndev); + + nps_enet_send_frame(ndev, skb); + + priv->tx_skb = skb; + + return NETDEV_TX_OK; +} + +#ifdef CONFIG_NET_POLL_CONTROLLER +static void nps_enet_poll_controller(struct net_device *ndev) +{ + disable_irq(ndev->irq); + nps_enet_irq_handler(ndev->irq, ndev); + enable_irq(ndev->irq); +} +#endif + +static const struct net_device_ops nps_netdev_ops = { + .ndo_open = nps_enet_open, + .ndo_stop = nps_enet_stop, + .ndo_start_xmit = nps_enet_start_xmit, + .ndo_set_mac_address = nps_enet_set_mac_address, + .ndo_set_rx_mode = nps_enet_set_rx_mode, +#ifdef CONFIG_NET_POLL_CONTROLLER + .ndo_poll_controller = nps_enet_poll_controller, +#endif +}; + +static s32 nps_enet_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct net_device *ndev; + struct nps_enet_priv *priv; + s32 err = 0; + const char *mac_addr; + struct resource *res_regs; + + if (!dev->of_node) + return -ENODEV; + + ndev = alloc_etherdev(sizeof(struct nps_enet_priv)); + if (!ndev) + return -ENOMEM; + + platform_set_drvdata(pdev, ndev); + SET_NETDEV_DEV(ndev, dev); + priv = netdev_priv(ndev); + + /* The EZ NET specific entries in the device structure. */ + ndev->netdev_ops = &nps_netdev_ops; + ndev->watchdog_timeo = (400 * HZ / 1000); + /* FIXME :: no multicast support yet */ + ndev->flags &= ~IFF_MULTICAST; + + res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + priv->regs_base = devm_ioremap_resource(dev, res_regs); + if (IS_ERR(priv->regs_base)) { + err = PTR_ERR(priv->regs_base); + goto out_netdev; + } + dev_dbg(dev, "Registers base address is 0x%p\n", priv->regs_base); + + /* set kernel MAC address to dev */ + mac_addr = of_get_mac_address(dev->of_node); + if (mac_addr) + ether_addr_copy(ndev->dev_addr, mac_addr); + else + eth_hw_addr_random(ndev); + + /* Get IRQ number */ + priv->irq = platform_get_irq(pdev, 0); + if (!priv->irq) { + dev_err(dev, "failed to retrieve <irq Rx-Tx> value from device tree\n"); + err = -ENODEV; + goto out_netdev; + } + + netif_napi_add(ndev, &priv->napi, nps_enet_poll, + NPS_ENET_NAPI_POLL_WEIGHT); + + /* Register the driver. Should be the last thing in probe */ + err = register_netdev(ndev); + if (err) { + dev_err(dev, "Failed to register ndev for %s, err = 0x%08x\n", + ndev->name, (s32)err); + goto out_netif_api; + } + + dev_info(dev, "(rx/tx=%d)\n", priv->irq); + return 0; + +out_netif_api: + netif_napi_del(&priv->napi); +out_netdev: + if (err) + free_netdev(ndev); + + return err; +} + +static s32 nps_enet_remove(struct platform_device *pdev) +{ + struct net_device *ndev = platform_get_drvdata(pdev); + struct nps_enet_priv *priv = netdev_priv(ndev); + + unregister_netdev(ndev); + free_netdev(ndev); + netif_napi_del(&priv->napi); + + return 0; +} + +static const struct of_device_id nps_enet_dt_ids[] = { + { .compatible = "ezchip,nps-mgt-enet" }, + { /* Sentinel */ } +}; + +static struct platform_driver nps_enet_driver = { + .probe = nps_enet_probe, + .remove = nps_enet_remove, + .driver = { + .name = DRV_NAME, + .of_match_table = nps_enet_dt_ids, + }, +}; + +module_platform_driver(nps_enet_driver); + +MODULE_AUTHOR("EZchip Semiconductor"); +MODULE_LICENSE("GPL v2"); |