On Thu, Aug 1, 2019 at 3:28 AM Avi Fishman <avifishman70@xxxxxxxxx> wrote:
>
> EMC Ethernet Media Access Controller supports 10/100 Mbps and
> RMII.
> This driver has been working on Nuvoton BMC NPCM7xx.
>
> Signed-off-by: Avi Fishman <avifishman70@xxxxxxxxx>
> +/* global setting for driver */
> +#define RX_QUEUE_LEN 128
> +#define TX_QUEUE_LEN 64
> +#define MAX_RBUFF_SZ 0x600
> +#define MAX_TBUFF_SZ 0x600
> +#define TX_TIMEOUT 50
> +#define DELAY 1000
> +#define CAM0 0x0
> +#define RX_POLL_SIZE 16
> +
> +#ifdef CONFIG_VLAN_8021Q
> +#define IS_VLAN 1
> +#else
> +#define IS_VLAN 0
> +#endif
> +
> +#define MAX_PACKET_SIZE (1514 + (IS_VLAN * 4))
1514 -> ETH_FRAME_LEN
4 -> VLAN_HLEN
Does this device support stacked VLAN?
Is this really the device maximum?
> +#define MAX_PACKET_SIZE_W_CRC (MAX_PACKET_SIZE + 4) /* 1518 */
4 -> ETH_FCS_LEN
> +#if defined CONFIG_NPCM7XX_EMC_ETH_DEBUG || defined CONFIG_DEBUG_FS
> +#define REG_PRINT(reg_name) {t = scnprintf(next, size, "%-10s = %08X\n", \
> + #reg_name, readl(ether->reg + (reg_name))); size -= t; next += t; }
> +#define DUMP_PRINT(f, x...) {t = scnprintf(next, size, f, ## x); size -= t; \
> + next += t; }
> +
> +static int npcm7xx_info_dump(char *buf, int count, struct net_device *netdev)
> +{
> + struct npcm7xx_ether *ether = netdev_priv(netdev);
> + struct npcm7xx_txbd *txbd;
> + struct npcm7xx_rxbd *rxbd;
> + unsigned long flags;
> + unsigned int i, cur, txd_offset, rxd_offset;
> + char *next = buf;
> + unsigned int size = count;
> + int t;
> + int is_locked = spin_is_locked(ðer->lock);
> +
> + if (!is_locked)
> + spin_lock_irqsave(ðer->lock, flags);
> +
> + /* ------basic driver information ---- */
> + DUMP_PRINT("NPCM7XX EMC %s driver version: %s\n", netdev->name,
> + DRV_MODULE_VERSION);
> +
> + REG_PRINT(REG_CAMCMR);
> + REG_PRINT(REG_CAMEN);
> + REG_PRINT(REG_CAMM_BASE);
> + REG_PRINT(REG_CAML_BASE);
> + REG_PRINT(REG_TXDLSA);
> + REG_PRINT(REG_RXDLSA);
> + REG_PRINT(REG_MCMDR);
> + REG_PRINT(REG_MIID);
> + REG_PRINT(REG_MIIDA);
> + REG_PRINT(REG_FFTCR);
> + REG_PRINT(REG_TSDR);
> + REG_PRINT(REG_RSDR);
> + REG_PRINT(REG_DMARFC);
> + REG_PRINT(REG_MIEN);
> + REG_PRINT(REG_MISTA);
> + REG_PRINT(REG_MGSTA);
> + REG_PRINT(REG_MPCNT);
> + writel(0x7FFF, (ether->reg + REG_MPCNT));
> + REG_PRINT(REG_MRPC);
> + REG_PRINT(REG_MRPCC);
> + REG_PRINT(REG_MREPC);
> + REG_PRINT(REG_DMARFS);
> + REG_PRINT(REG_CTXDSA);
> + REG_PRINT(REG_CTXBSA);
> + REG_PRINT(REG_CRXDSA);
> + REG_PRINT(REG_CRXBSA);
> + REG_PRINT(REG_RXFSM);
> + REG_PRINT(REG_TXFSM);
> + REG_PRINT(REG_FSM0);
> + REG_PRINT(REG_FSM1);
> + REG_PRINT(REG_DCR);
> + REG_PRINT(REG_DMMIR);
> + REG_PRINT(REG_BISTR);
> + DUMP_PRINT("\n");
> +
> + DUMP_PRINT("netif_queue %s\n\n", netif_queue_stopped(netdev) ?
> + "Stopped" : "Running");
> + if (ether->rdesc)
> + DUMP_PRINT("napi is %s\n\n", test_bit(NAPI_STATE_SCHED,
> + ðer->napi.state) ?
> + "scheduled" :
> + "not scheduled");
> +
> + txd_offset = (readl((ether->reg + REG_CTXDSA)) -
> + readl((ether->reg + REG_TXDLSA))) /
> + sizeof(struct npcm7xx_txbd);
> + DUMP_PRINT("TXD offset %6d\n", txd_offset);
> + DUMP_PRINT("cur_tx %6d\n", ether->cur_tx);
> + DUMP_PRINT("finish_tx %6d\n", ether->finish_tx);
> + DUMP_PRINT("pending_tx %6d\n", ether->pending_tx);
> + /* debug counters */
> + DUMP_PRINT("tx_tdu %6d\n", ether->tx_tdu);
> + ether->tx_tdu = 0;
> + DUMP_PRINT("tx_tdu_i %6d\n", ether->tx_tdu_i);
> + ether->tx_tdu_i = 0;
> + DUMP_PRINT("tx_cp_i %6d\n", ether->tx_cp_i);
> + ether->tx_cp_i = 0;
> + DUMP_PRINT("tx_int_count %6d\n", ether->tx_int_count);
> + ether->tx_int_count = 0;
> + DUMP_PRINT("count_xmit tx %6d\n", ether->count_xmit);
> + ether->count_xmit = 0;
> + DUMP_PRINT("count_finish %6d\n", ether->count_finish);
> + ether->count_finish = 0;
> + DUMP_PRINT("\n");
> +
> + rxd_offset = (readl((ether->reg + REG_CRXDSA)) -
> + readl((ether->reg + REG_RXDLSA)))
> + / sizeof(struct npcm7xx_txbd);
> + DUMP_PRINT("RXD offset %6d\n", rxd_offset);
> + DUMP_PRINT("cur_rx %6d\n", ether->cur_rx);
> + DUMP_PRINT("rx_err %6d\n", ether->rx_err);
> + ether->rx_err = 0;
> + DUMP_PRINT("rx_berr %6d\n", ether->rx_berr);
> + ether->rx_berr = 0;
> + DUMP_PRINT("rx_stuck %6d\n", ether->rx_stuck);
> + ether->rx_stuck = 0;
> + DUMP_PRINT("rdu %6d\n", ether->rdu);
> + ether->rdu = 0;
> + DUMP_PRINT("rxov rx %6d\n", ether->rxov);
> + ether->rxov = 0;
> + /* debug counters */
> + DUMP_PRINT("rx_int_count %6d\n", ether->rx_int_count);
> + ether->rx_int_count = 0;
> + DUMP_PRINT("rx_err_count %6d\n", ether->rx_err_count);
> + ether->rx_err_count = 0;
Basic counters like tx_packets and rx_errors are probably better
exported regardless of debug level as net_device_stats. And then don't
need to be copied in debug output.
Less standard counters like tx interrupt count are probably better
candidates for ethtool -S.
> +#ifdef CONFIG_NPCM7XX_EMC_ETH_DEBUG
> +static void npcm7xx_info_print(struct net_device *netdev)
> +{
> + char *emc_dump_buf;
> + int count;
> + struct npcm7xx_ether *ether;
> + struct platform_device *pdev;
> + char c;
> + char *tmp_buf;
> + const size_t print_size = 5 * PAGE_SIZE;
> +
> + ether = netdev_priv(netdev);
> + pdev = ether->pdev;
> +
> + emc_dump_buf = kmalloc(print_size, GFP_KERNEL);
> + if (!emc_dump_buf)
> + return;
> +
> + tmp_buf = emc_dump_buf;
> + count = npcm7xx_info_dump(emc_dump_buf, print_size, netdev);
> + while (count > 512) {
> + c = tmp_buf[512];
> + tmp_buf[512] = 0;
> + dev_info(&pdev->dev, "%s", tmp_buf);
> + tmp_buf += 512;
> + tmp_buf[0] = c;
> + count -= 512;
Missing closing parenthesis.
Also, why this buffering to printk?
> +static void npcm7xx_write_cam(struct net_device *netdev,
> + unsigned int x, unsigned char *pval)
> +{
> + struct npcm7xx_ether *ether = netdev_priv(netdev);
> + __le32 msw, lsw;
> +
> + msw = (pval[0] << 24) | (pval[1] << 16) | (pval[2] << 8) | pval[3];
> +
> + lsw = (pval[4] << 24) | (pval[5] << 16);
Does __le32 plus this explicit shifting define host endianness? Better
to keep independent?
> +
> + writel(lsw, (ether->reg + REG_CAML_BASE) + x * CAM_ENTRY_SIZE);
> + writel(msw, (ether->reg + REG_CAMM_BASE) + x * CAM_ENTRY_SIZE);
> + dev_dbg(ðer->pdev->dev,
> + "REG_CAML_BASE = 0x%08X REG_CAMM_BASE = 0x%08X", lsw, msw);
> +}
> +
> +static struct sk_buff *get_new_skb(struct net_device *netdev, u32 i)
> +{
> + __le32 buffer;
> + struct npcm7xx_ether *ether = netdev_priv(netdev);
> + struct sk_buff *skb = netdev_alloc_skb(netdev,
> + roundup(MAX_PACKET_SIZE_W_CRC, 4));
> +
> + if (unlikely(!skb)) {
> + if (net_ratelimit())
> + netdev_warn(netdev, "failed to allocate rx skb\n");
can use net_warn_ratelimited (here and elsewhere)
> + buffer = ether->rx_scratch_dma;
> + } else {
> + /* Do not unmark the following skb_reserve() Receive Buffer
> + * Starting Address must be aligned to 4 bytes and the following
> + * line if unmarked will make it align to 2 and this likely will
> + * hult the RX and crash the linux
halt?
> + * skb_reserve(skb, NET_IP_ALIGN);
> + */
> + skb->dev = netdev;
> + buffer = dma_map_single(&netdev->dev,
> + skb->data,
> + roundup(MAX_PACKET_SIZE_W_CRC, 4),
> + DMA_FROM_DEVICE);
> + if (unlikely(dma_mapping_error(&netdev->dev, buffer))) {
> + if (net_ratelimit())
> + netdev_err(netdev, "failed to map rx page\n");
> + dev_kfree_skb_any(skb);
> + buffer = ether->rx_scratch_dma;
> + skb = NULL;
> + }
> + }
> + ether->rx_skb[i] = skb;
> + ether->rdesc[i].buffer = buffer;
> +
> + return skb;
> +}
> +
> +static int npcm7xx_ether_close(struct net_device *netdev)
> +{
> + struct npcm7xx_ether *ether = netdev_priv(netdev);
> +
> + npcm7xx_return_default_idle(netdev);
> +
> + if (ether->phy_dev)
> + phy_stop(ether->phy_dev);
> + else if (ether->use_ncsi)
> + ncsi_stop_dev(ether->ncsidev);
> +
> + msleep(20);
> +
> + free_irq(ether->txirq, netdev);
> + free_irq(ether->rxirq, netdev);
> +
> + netif_stop_queue(netdev);
> + napi_disable(ðer->napi);
Cleanup state in reverse of allocation.
> +static int npcm7xx_ether_start_xmit(struct sk_buff *skb, struct net_device *netdev)
> +{
> + struct npcm7xx_ether *ether = netdev_priv(netdev);
> + struct npcm7xx_txbd *txbd;
> + unsigned long flags;
> +
> + ether->count_xmit++;
> +
> + /* Insert new buffer */
> + txbd = (ether->tdesc + ether->cur_tx);
> + txbd->buffer = dma_map_single(&netdev->dev, skb->data, skb->len,
> + DMA_TO_DEVICE);
> + ether->tx_skb[ether->cur_tx] = skb;
> + if (skb->len > MAX_PACKET_SIZE)
> + dev_err(ðer->pdev->dev,
> + "skb->len (= %d) > MAX_PACKET_SIZE (= %d)\n",
> + skb->len, MAX_PACKET_SIZE);
> + txbd->sl = skb->len > MAX_PACKET_SIZE ? MAX_PACKET_SIZE : skb->len;
Check for errors before mapping to device, and drop packet? Probably
don't want to output truncated packets.
Also rate limit such messages.
> + dma_wmb();
> +
> + txbd->mode = TX_OWN_DMA | PADDINGMODE | CRCMODE;
> +
> + /* make sure that data is in memory before we trigger TX */
> + wmb();
> +
> + /* trigger TX */
> + writel(ENSTART, (ether->reg + REG_TSDR));
> +
> + if (++ether->cur_tx >= TX_QUEUE_LEN)
> + ether->cur_tx = 0;
> +
> + spin_lock_irqsave(ðer->lock, flags);
> + ether->pending_tx++;
> +
> + /* sometimes we miss the tx interrupt due to HW issue, so NAPI will not
> + * clean the pending tx, so we clean it also here
> + */
> + npcm7xx_clean_tx(netdev, true);
> +
> + if (ether->pending_tx >= TX_QUEUE_LEN - 1) {
> + __le32 reg_mien;
> + unsigned int index_to_wake = ether->cur_tx +
> + ((TX_QUEUE_LEN * 3) / 4);
> +
> + if (index_to_wake >= TX_QUEUE_LEN)
> + index_to_wake -= TX_QUEUE_LEN;
> +
> + txbd = (ether->tdesc + index_to_wake);
> + txbd->mode = TX_OWN_DMA | PADDINGMODE | CRCMODE | MACTXINTEN;
> +
> + /* make sure that data is in memory before we trigger TX */
> + wmb();
> +
> + /* Clear TDU interrupt */
> + writel(MISTA_TDU, (ether->reg + REG_MISTA));
> +
> + /* due to HW issue somtimes, we miss the TX interrupt we just
somtimes -> sometimes
> + * set (MACTXINTEN), so we also set TDU for Transmit
> + * Descriptor Unavailable interrupt
> + */
> + reg_mien = readl((ether->reg + REG_MIEN));
> + if (reg_mien != 0)
> + /* Enable TDU interrupt */
> + writel(reg_mien | ENTDU, (ether->reg + REG_MIEN));
> +
> + ether->tx_tdu++;
> + netif_stop_queue(netdev);
> + }
> +
> + spin_unlock_irqrestore(ðer->lock, flags);
> +
> + return 0;
> +}
> +
> +static irqreturn_t npcm7xx_tx_interrupt(int irq, void *dev_id)
> +{
> + struct npcm7xx_ether *ether;
> + struct platform_device *pdev;
> + struct net_device *netdev;
> + __le32 status;
> + unsigned long flags;
> +
> + netdev = dev_id;
> + ether = netdev_priv(netdev);
> + pdev = ether->pdev;
> +
> + npcm7xx_get_and_clear_int(netdev, &status, 0xFFFF0000);
> +
> + ether->tx_int_count++;
> +
> + if (status & MISTA_EXDEF)
> + dev_err(&pdev->dev, "emc defer exceed interrupt status=0x%08X\n"
> + , status);
> + else if (status & MISTA_TXBERR) {
> + dev_err(&pdev->dev, "emc bus error interrupt status=0x%08X\n",
> + status);
> +#ifdef CONFIG_NPCM7XX_EMC_ETH_DEBUG
> + npcm7xx_info_print(netdev);
> +#endif
> + spin_lock_irqsave(ðer->lock, flags);
irqsave in hard interrupt context?
> + writel(0, (ether->reg + REG_MIEN)); /* disable any interrupt */
> + spin_unlock_irqrestore(ðer->lock, flags);
> + ether->need_reset = 1;
> + } else if (status & ~(MISTA_TXINTR | MISTA_TXCP | MISTA_TDU))
> + dev_err(&pdev->dev, "emc other error interrupt status=0x%08X\n",
> + status);
> +
> + /* if we got MISTA_TXCP | MISTA_TDU remove those interrupt and call napi */
The goal of napi is to keep interrupts disabled until napi completes.
> + if (status & (MISTA_TXCP | MISTA_TDU) &
> + readl((ether->reg + REG_MIEN))) {
> + __le32 reg_mien;
> +
> + spin_lock_irqsave(ðer->lock, flags);
> + reg_mien = readl((ether->reg + REG_MIEN));
> + if (reg_mien & ENTDU)
> + /* Disable TDU interrupt */
> + writel(reg_mien & (~ENTDU), (ether->reg + REG_MIEN));
> +
> + spin_unlock_irqrestore(ðer->lock, flags);
> +
> + if (status & MISTA_TXCP)
> + ether->tx_cp_i++;
> + if (status & MISTA_TDU)
> + ether->tx_tdu_i++;
> + } else {
> + dev_dbg(&pdev->dev, "status=0x%08X\n", status);
> + }
> +
> + napi_schedule(ðer->napi);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t npcm7xx_rx_interrupt(int irq, void *dev_id)
> +{
> + struct net_device *netdev = (struct net_device *)dev_id;
> + struct npcm7xx_ether *ether = netdev_priv(netdev);
> + struct platform_device *pdev = ether->pdev;
> + __le32 status;
> + unsigned long flags;
> + unsigned int any_err = 0;
> + __le32 rxfsm;
> +
> + npcm7xx_get_and_clear_int(netdev, &status, 0xFFFF);
Same here
> +static int npcm7xx_poll(struct napi_struct *napi, int budget)
> +{
> + struct npcm7xx_ether *ether =
> + container_of(napi, struct npcm7xx_ether, napi);
> + struct npcm7xx_rxbd *rxbd;
> + struct net_device *netdev = ether->netdev;
> + struct platform_device *pdev = ether->pdev;
> + struct sk_buff *s;
> + unsigned int length;
> + __le32 status;
> + unsigned long flags;
> + int rx_cnt = 0;
> + int complete = 0;
> + unsigned int rx_offset = (readl((ether->reg + REG_CRXDSA)) -
> + ether->start_rx_ptr) /
> + sizeof(struct npcm7xx_txbd);
> + unsigned int local_count = (rx_offset >= ether->cur_rx) ?
> + rx_offset - ether->cur_rx : rx_offset +
> + RX_QUEUE_LEN - ether->cur_rx;
> +
> + if (local_count > ether->max_waiting_rx)
> + ether->max_waiting_rx = local_count;
> +
> + if (local_count > (4 * RX_POLL_SIZE))
> + /* we are porbably in a storm of short packets and we don't
porbably - probably
> + * want to get into RDU since short packets in RDU cause
> + * many RXOV which may cause EMC halt, so we filter out all
> + * coming packets
> + */
> + writel(0, (ether->reg + REG_CAMCMR));
> +
> + if (local_count <= budget)
> + /* we can restore accepting of packets */
> + writel(ether->camcmr, (ether->reg + REG_CAMCMR));
> +
> + spin_lock_irqsave(ðer->lock, flags);
> + npcm7xx_clean_tx(netdev, false);
> + spin_unlock_irqrestore(ðer->lock, flags);
> +
> + rxbd = (ether->rdesc + ether->cur_rx);
> +
> + while (rx_cnt < budget) {
> + status = rxbd->sl;
> + if ((status & RX_OWN_DMA) == RX_OWN_DMA) {
> + complete = 1;
> + break;
> + }
> + /* for debug puposes we save the previous value */
puposes -> purposes
> + rxbd->reserved = status;
> + s = ether->rx_skb[ether->cur_rx];
> + length = status & 0xFFFF;
> +
> + /* If VLAN is not supporte RXDS_PTLE (packet too long) is also
supporte -> supported (stopping pointing out typos after this).
> +static const struct net_device_ops npcm7xx_ether_netdev_ops = {
> + .ndo_open = npcm7xx_ether_open,
> + .ndo_stop = npcm7xx_ether_close,
> + .ndo_start_xmit = npcm7xx_ether_start_xmit,
> + .ndo_get_stats = npcm7xx_ether_stats,
> + .ndo_set_rx_mode = npcm7xx_ether_set_rx_mode,
> + .ndo_set_mac_address = npcm7xx_set_mac_address,
> + .ndo_do_ioctl = npcm7xx_ether_ioctl,
> + .ndo_validate_addr = eth_validate_addr,
> + .ndo_change_mtu = eth_change_mtu,
This is marked as deprecated. Also in light of the hardcoded
MAX_PACKET_SIZE, probably want to set dev->max_mtu.
> +static int npcm7xx_ether_probe(struct platform_device *pdev)
> +{
> + struct npcm7xx_ether *ether;
> + struct net_device *netdev;
> + int error;
> +
> + struct clk *emc_clk = NULL;
> + struct device_node *np = pdev->dev.of_node;
> +
> + pdev->id = of_alias_get_id(np, "ethernet");
> + if (pdev->id < 0)
> + pdev->id = 0;
> +
> + emc_clk = devm_clk_get(&pdev->dev, NULL);
> +
> + if (IS_ERR(emc_clk))
> + return PTR_ERR(emc_clk);
> +
> + /* Enable Clock */
> + clk_prepare_enable(emc_clk);
> +
> + error = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> + if (error)
> + return -ENODEV;
> +
> + netdev = alloc_etherdev(sizeof(struct npcm7xx_ether));
> + if (!netdev)
> + return -ENOMEM;
> +
> + ether = netdev_priv(netdev);
> +
> + ether->reset = devm_reset_control_get(&pdev->dev, NULL);
> + if (IS_ERR(ether->reset))
> + return PTR_ERR(ether->reset);
Memory leak on error path
Also missing netif_napi_del in npcm7xx_ether_remove?
