diff options
Diffstat (limited to 'drivers/net/ks8842.c')
| -rw-r--r-- | drivers/net/ks8842.c | 464 |
1 files changed, 443 insertions, 21 deletions
diff --git a/drivers/net/ks8842.c b/drivers/net/ks8842.c index 289b0be..3fe38c7 100644 --- a/drivers/net/ks8842.c +++ b/drivers/net/ks8842.c @@ -30,6 +30,9 @@ #include <linux/etherdevice.h> #include <linux/ethtool.h> #include <linux/ks8842.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/scatterlist.h> #define DRV_NAME "ks8842" @@ -82,6 +85,15 @@ #define IRQ_RX_ERROR 0x0080 #define ENABLED_IRQS (IRQ_LINK_CHANGE | IRQ_TX | IRQ_RX | IRQ_RX_STOPPED | \ IRQ_TX_STOPPED | IRQ_RX_OVERRUN | IRQ_RX_ERROR) +/* When running via timberdale in DMA mode, the RX interrupt should be + enabled in the KS8842, but not in the FPGA IP, since the IP handles + RX DMA internally. + TX interrupts are not needed it is handled by the FPGA the driver is + notified via DMA callbacks. +*/ +#define ENABLED_IRQS_DMA_IP (IRQ_LINK_CHANGE | IRQ_RX_STOPPED | \ + IRQ_TX_STOPPED | IRQ_RX_OVERRUN | IRQ_RX_ERROR) +#define ENABLED_IRQS_DMA (ENABLED_IRQS_DMA_IP | IRQ_RX) #define REG_ISR 0x02 #define REG_RXSR 0x04 #define RXSR_VALID 0x8000 @@ -124,6 +136,28 @@ #define MICREL_KS884X 0x01 /* 0=Timeberdale(FPGA), 1=Micrel */ #define KS884X_16BIT 0x02 /* 1=16bit, 0=32bit */ +#define DMA_BUFFER_SIZE 2048 + +struct ks8842_tx_dma_ctl { + struct dma_chan *chan; + struct dma_async_tx_descriptor *adesc; + void *buf; + struct scatterlist sg; + int channel; +}; + +struct ks8842_rx_dma_ctl { + struct dma_chan *chan; + struct dma_async_tx_descriptor *adesc; + struct sk_buff *skb; + struct scatterlist sg; + struct tasklet_struct tasklet; + int channel; +}; + +#define KS8842_USE_DMA(adapter) (((adapter)->dma_tx.channel != -1) && \ + ((adapter)->dma_rx.channel != -1)) + struct ks8842_adapter { void __iomem *hw_addr; int irq; @@ -132,8 +166,19 @@ struct ks8842_adapter { spinlock_t lock; /* spinlock to be interrupt safe */ struct work_struct timeout_work; struct net_device *netdev; + struct device *dev; + struct ks8842_tx_dma_ctl dma_tx; + struct ks8842_rx_dma_ctl dma_rx; }; +static void ks8842_dma_rx_cb(void *data); +static void ks8842_dma_tx_cb(void *data); + +static inline void ks8842_resume_dma(struct ks8842_adapter *adapter) +{ + iowrite32(1, adapter->hw_addr + REQ_TIMB_DMA_RESUME); +} + static inline void ks8842_select_bank(struct ks8842_adapter *adapter, u16 bank) { iowrite16(bank, adapter->hw_addr + REG_SELECT_BANK); @@ -297,8 +342,19 @@ static void ks8842_reset_hw(struct ks8842_adapter *adapter) ks8842_write16(adapter, 18, 0xffff, REG_ISR); /* enable interrupts */ - ks8842_write16(adapter, 18, ENABLED_IRQS, REG_IER); - + if (KS8842_USE_DMA(adapter)) { + /* When running in DMA Mode the RX interrupt is not enabled in + timberdale because RX data is received by DMA callbacks + it must still be enabled in the KS8842 because it indicates + to timberdale when there is RX data for it's DMA FIFOs */ + iowrite16(ENABLED_IRQS_DMA_IP, adapter->hw_addr + REG_TIMB_IER); + ks8842_write16(adapter, 18, ENABLED_IRQS_DMA, REG_IER); + } else { + if (!(adapter->conf_flags & MICREL_KS884X)) + iowrite16(ENABLED_IRQS, + adapter->hw_addr + REG_TIMB_IER); + ks8842_write16(adapter, 18, ENABLED_IRQS, REG_IER); + } /* enable the switch */ ks8842_write16(adapter, 32, 0x1, REG_SW_ID_AND_ENABLE); } @@ -371,6 +427,53 @@ static inline u16 ks8842_tx_fifo_space(struct ks8842_adapter *adapter) return ks8842_read16(adapter, 16, REG_TXMIR) & 0x1fff; } +static int ks8842_tx_frame_dma(struct sk_buff *skb, struct net_device *netdev) +{ + struct ks8842_adapter *adapter = netdev_priv(netdev); + struct ks8842_tx_dma_ctl *ctl = &adapter->dma_tx; + u8 *buf = ctl->buf; + + if (ctl->adesc) { + netdev_dbg(netdev, "%s: TX ongoing\n", __func__); + /* transfer ongoing */ + return NETDEV_TX_BUSY; + } + + sg_dma_len(&ctl->sg) = skb->len + sizeof(u32); + + /* copy data to the TX buffer */ + /* the control word, enable IRQ, port 1 and the length */ + *buf++ = 0x00; + *buf++ = 0x01; /* Port 1 */ + *buf++ = skb->len & 0xff; + *buf++ = (skb->len >> 8) & 0xff; + skb_copy_from_linear_data(skb, buf, skb->len); + + dma_sync_single_range_for_device(adapter->dev, + sg_dma_address(&ctl->sg), 0, sg_dma_len(&ctl->sg), + DMA_TO_DEVICE); + + /* make sure the length is a multiple of 4 */ + if (sg_dma_len(&ctl->sg) % 4) + sg_dma_len(&ctl->sg) += 4 - sg_dma_len(&ctl->sg) % 4; + + ctl->adesc = ctl->chan->device->device_prep_slave_sg(ctl->chan, + &ctl->sg, 1, DMA_TO_DEVICE, + DMA_PREP_INTERRUPT | DMA_COMPL_SKIP_SRC_UNMAP); + if (!ctl->adesc) + return NETDEV_TX_BUSY; + + ctl->adesc->callback_param = netdev; + ctl->adesc->callback = ks8842_dma_tx_cb; + ctl->adesc->tx_submit(ctl->adesc); + + netdev->stats.tx_bytes += skb->len; + + dev_kfree_skb(skb); + + return NETDEV_TX_OK; +} + static int ks8842_tx_frame(struct sk_buff *skb, struct net_device *netdev) { struct ks8842_adapter *adapter = netdev_priv(netdev); @@ -422,6 +525,121 @@ static int ks8842_tx_frame(struct sk_buff *skb, struct net_device *netdev) return NETDEV_TX_OK; } +static void ks8842_update_rx_err_counters(struct net_device *netdev, u32 status) +{ + netdev_dbg(netdev, "RX error, status: %x\n", status); + + netdev->stats.rx_errors++; + if (status & RXSR_TOO_LONG) + netdev->stats.rx_length_errors++; + if (status & RXSR_CRC_ERROR) + netdev->stats.rx_crc_errors++; + if (status & RXSR_RUNT) + netdev->stats.rx_frame_errors++; +} + +static void ks8842_update_rx_counters(struct net_device *netdev, u32 status, + int len) +{ + netdev_dbg(netdev, "RX packet, len: %d\n", len); + + netdev->stats.rx_packets++; + netdev->stats.rx_bytes += len; + if (status & RXSR_MULTICAST) + netdev->stats.multicast++; +} + +static int __ks8842_start_new_rx_dma(struct net_device *netdev) +{ + struct ks8842_adapter *adapter = netdev_priv(netdev); + struct ks8842_rx_dma_ctl *ctl = &adapter->dma_rx; + struct scatterlist *sg = &ctl->sg; + int err; + + ctl->skb = netdev_alloc_skb(netdev, DMA_BUFFER_SIZE); + if (ctl->skb) { + sg_init_table(sg, 1); + sg_dma_address(sg) = dma_map_single(adapter->dev, + ctl->skb->data, DMA_BUFFER_SIZE, DMA_FROM_DEVICE); + err = dma_mapping_error(adapter->dev, sg_dma_address(sg)); + if (unlikely(err)) { + sg_dma_address(sg) = 0; + goto out; + } + + sg_dma_len(sg) = DMA_BUFFER_SIZE; + + ctl->adesc = ctl->chan->device->device_prep_slave_sg(ctl->chan, + sg, 1, DMA_FROM_DEVICE, + DMA_PREP_INTERRUPT | DMA_COMPL_SKIP_SRC_UNMAP); + + if (!ctl->adesc) + goto out; + + ctl->adesc->callback_param = netdev; + ctl->adesc->callback = ks8842_dma_rx_cb; + ctl->adesc->tx_submit(ctl->adesc); + } else { + err = -ENOMEM; + sg_dma_address(sg) = 0; + goto out; + } + + return err; +out: + if (sg_dma_address(sg)) + dma_unmap_single(adapter->dev, sg_dma_address(sg), + DMA_BUFFER_SIZE, DMA_FROM_DEVICE); + sg_dma_address(sg) = 0; + if (ctl->skb) + dev_kfree_skb(ctl->skb); + + ctl->skb = NULL; + + printk(KERN_ERR DRV_NAME": Failed to start RX DMA: %d\n", err); + return err; +} + +static void ks8842_rx_frame_dma_tasklet(unsigned long arg) +{ + struct net_device *netdev = (struct net_device *)arg; + struct ks8842_adapter *adapter = netdev_priv(netdev); + struct ks8842_rx_dma_ctl *ctl = &adapter->dma_rx; + struct sk_buff *skb = ctl->skb; + dma_addr_t addr = sg_dma_address(&ctl->sg); + u32 status; + + ctl->adesc = NULL; + + /* kick next transfer going */ + __ks8842_start_new_rx_dma(netdev); + + /* now handle the data we got */ + dma_unmap_single(adapter->dev, addr, DMA_BUFFER_SIZE, DMA_FROM_DEVICE); + + status = *((u32 *)skb->data); + + netdev_dbg(netdev, "%s - rx_data: status: %x\n", + __func__, status & 0xffff); + + /* check the status */ + if ((status & RXSR_VALID) && !(status & RXSR_ERROR)) { + int len = (status >> 16) & 0x7ff; + + ks8842_update_rx_counters(netdev, status, len); + + /* reserve 4 bytes which is the status word */ + skb_reserve(skb, 4); + skb_put(skb, len); + + skb->protocol = eth_type_trans(skb, netdev); + netif_rx(skb); + } else { + ks8842_update_rx_err_counters(netdev, status); + dev_kfree_skb(skb); + } +} + static void ks8842_rx_frame(struct net_device *netdev, struct ks8842_adapter *adapter) { @@ -445,13 +663,9 @@ static void ks8842_rx_frame(struct net_device *netdev, if ((status & RXSR_VALID) && !(status & RXSR_ERROR)) { struct sk_buff *skb = netdev_alloc_skb_ip_align(netdev, len); - netdev_dbg(netdev, "%s, got package, len: %d\n", __func__, len); if (skb) { - netdev->stats.rx_packets++; - netdev->stats.rx_bytes += len; - if (status & RXSR_MULTICAST) - netdev->stats.multicast++; + ks8842_update_rx_counters(netdev, status, len); if (adapter->conf_flags & KS884X_16BIT) { u16 *data16 = (u16 *)skb_put(skb, len); @@ -477,16 +691,8 @@ static void ks8842_rx_frame(struct net_device *netdev, netif_rx(skb); } else netdev->stats.rx_dropped++; - } else { - netdev_dbg(netdev, "RX error, status: %x\n", status); - netdev->stats.rx_errors++; - if (status & RXSR_TOO_LONG) - netdev->stats.rx_length_errors++; - if (status & RXSR_CRC_ERROR) - netdev->stats.rx_crc_errors++; - if (status & RXSR_RUNT) - netdev->stats.rx_frame_errors++; - } + } else + ks8842_update_rx_err_counters(netdev, status); /* set high watermark to 3K */ ks8842_clear_bits(adapter, 0, 1 << 12, REG_QRFCR); @@ -541,6 +747,12 @@ void ks8842_tasklet(unsigned long arg) isr = ks8842_read16(adapter, 18, REG_ISR); netdev_dbg(netdev, "%s - ISR: 0x%x\n", __func__, isr); + /* when running in DMA mode, do not ack RX interrupts, it is handled + internally by timberdale, otherwise it's DMA FIFO:s would stop + */ + if (KS8842_USE_DMA(adapter)) + isr &= ~IRQ_RX; + /* Ack */ ks8842_write16(adapter, 18, isr, REG_ISR); @@ -554,9 +766,11 @@ void ks8842_tasklet(unsigned long arg) if (isr & IRQ_LINK_CHANGE) ks8842_update_link_status(netdev, adapter); - if (isr & (IRQ_RX | IRQ_RX_ERROR)) + /* should not get IRQ_RX when running DMA mode */ + if (isr & (IRQ_RX | IRQ_RX_ERROR) && !KS8842_USE_DMA(adapter)) ks8842_handle_rx(netdev, adapter); + /* should only happen when in PIO mode */ if (isr & IRQ_TX) ks8842_handle_tx(netdev, adapter); @@ -575,8 +789,17 @@ void ks8842_tasklet(unsigned long arg) /* re-enable interrupts, put back the bank selection register */ spin_lock_irqsave(&adapter->lock, flags); - ks8842_write16(adapter, 18, ENABLED_IRQS, REG_IER); + if (KS8842_USE_DMA(adapter)) + ks8842_write16(adapter, 18, ENABLED_IRQS_DMA, REG_IER); + else + ks8842_write16(adapter, 18, ENABLED_IRQS, REG_IER); iowrite16(entry_bank, adapter->hw_addr + REG_SELECT_BANK); + + /* Make sure timberdale continues DMA operations, they are stopped while + we are handling the ks8842 because we might change bank */ + if (KS8842_USE_DMA(adapter)) + ks8842_resume_dma(adapter); + spin_unlock_irqrestore(&adapter->lock, flags); } @@ -592,8 +815,12 @@ static irqreturn_t ks8842_irq(int irq, void *devid) netdev_dbg(netdev, "%s - ISR: 0x%x\n", __func__, isr); if (isr) { - /* disable IRQ */ - ks8842_write16(adapter, 18, 0x00, REG_IER); + if (KS8842_USE_DMA(adapter)) + /* disable all but RX IRQ, since the FPGA relies on it*/ + ks8842_write16(adapter, 18, IRQ_RX, REG_IER); + else + /* disable IRQ */ + ks8842_write16(adapter, 18, 0x00, REG_IER); /* schedule tasklet */ tasklet_schedule(&adapter->tasklet); @@ -603,9 +830,151 @@ static irqreturn_t ks8842_irq(int irq, void *devid) iowrite16(entry_bank, adapter->hw_addr + REG_SELECT_BANK); + /* After an interrupt, tell timberdale to continue DMA operations. + DMA is disabled while we are handling the ks8842 because we might + change bank */ + ks8842_resume_dma(adapter); + return ret; } +static void ks8842_dma_rx_cb(void *data) +{ + struct net_device *netdev = data; + struct ks8842_adapter *adapter = netdev_priv(netdev); + + netdev_dbg(netdev, "RX DMA finished\n"); + /* schedule tasklet */ + if (adapter->dma_rx.adesc) + tasklet_schedule(&adapter->dma_rx.tasklet); +} + +static void ks8842_dma_tx_cb(void *data) +{ + struct net_device *netdev = data; + struct ks8842_adapter *adapter = netdev_priv(netdev); + struct ks8842_tx_dma_ctl *ctl = &adapter->dma_tx; + + netdev_dbg(netdev, "TX DMA finished\n"); + + if (!ctl->adesc) + return; + + netdev->stats.tx_packets++; + ctl->adesc = NULL; + + if (netif_queue_stopped(netdev)) + netif_wake_queue(netdev); +} + +static void ks8842_stop_dma(struct ks8842_adapter *adapter) +{ + struct ks8842_tx_dma_ctl *tx_ctl = &adapter->dma_tx; + struct ks8842_rx_dma_ctl *rx_ctl = &adapter->dma_rx; + + tx_ctl->adesc = NULL; + if (tx_ctl->chan) + tx_ctl->chan->device->device_control(tx_ctl->chan, + DMA_TERMINATE_ALL, 0); + + rx_ctl->adesc = NULL; + if (rx_ctl->chan) + rx_ctl->chan->device->device_control(rx_ctl->chan, + DMA_TERMINATE_ALL, 0); + + if (sg_dma_address(&rx_ctl->sg)) + dma_unmap_single(adapter->dev, sg_dma_address(&rx_ctl->sg), + DMA_BUFFER_SIZE, DMA_FROM_DEVICE); + sg_dma_address(&rx_ctl->sg) = 0; + + dev_kfree_skb(rx_ctl->skb); + rx_ctl->skb = NULL; +} + +static void ks8842_dealloc_dma_bufs(struct ks8842_adapter *adapter) +{ + struct ks8842_tx_dma_ctl *tx_ctl = &adapter->dma_tx; + struct ks8842_rx_dma_ctl *rx_ctl = &adapter->dma_rx; + + ks8842_stop_dma(adapter); + + if (tx_ctl->chan) + dma_release_channel(tx_ctl->chan); + tx_ctl->chan = NULL; + + if (rx_ctl->chan) + dma_release_channel(rx_ctl->chan); + rx_ctl->chan = NULL; + + tasklet_kill(&rx_ctl->tasklet); + + if (sg_dma_address(&tx_ctl->sg)) + dma_unmap_single(adapter->dev, sg_dma_address(&tx_ctl->sg), + DMA_BUFFER_SIZE, DMA_TO_DEVICE); + sg_dma_address(&tx_ctl->sg) = 0; + + kfree(tx_ctl->buf); + tx_ctl->buf = NULL; +} + +static bool ks8842_dma_filter_fn(struct dma_chan *chan, void *filter_param) +{ + return chan->chan_id == (int)filter_param; +} + +static int ks8842_alloc_dma_bufs(struct net_device *netdev) +{ + struct ks8842_adapter *adapter = netdev_priv(netdev); + struct ks8842_tx_dma_ctl *tx_ctl = &adapter->dma_tx; + struct ks8842_rx_dma_ctl *rx_ctl = &adapter->dma_rx; + int err; + + dma_cap_mask_t mask; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + dma_cap_set(DMA_PRIVATE, mask); + + sg_init_table(&tx_ctl->sg, 1); + + tx_ctl->chan = dma_request_channel(mask, ks8842_dma_filter_fn, + (void *)tx_ctl->channel); + if (!tx_ctl->chan) { + err = -ENODEV; + goto err; + } + + /* allocate DMA buffer */ + tx_ctl->buf = kmalloc(DMA_BUFFER_SIZE, GFP_KERNEL); + if (!tx_ctl->buf) { + err = -ENOMEM; + goto err; + } + + sg_dma_address(&tx_ctl->sg) = dma_map_single(adapter->dev, + tx_ctl->buf, DMA_BUFFER_SIZE, DMA_TO_DEVICE); + err = dma_mapping_error(adapter->dev, + sg_dma_address(&tx_ctl->sg)); + if (err) { + sg_dma_address(&tx_ctl->sg) = 0; + goto err; + } + + rx_ctl->chan = dma_request_channel(mask, ks8842_dma_filter_fn, + (void *)rx_ctl->channel); + if (!rx_ctl->chan) { + err = -ENODEV; + goto err; + } + + tasklet_init(&rx_ctl->tasklet, ks8842_rx_frame_dma_tasklet, + (unsigned long)netdev); + + return 0; +err: + ks8842_dealloc_dma_bufs(adapter); + return err; +} /* Netdevice operations */ @@ -616,6 +985,25 @@ static int ks8842_open(struct net_device *netdev) netdev_dbg(netdev, "%s - entry\n", __func__); + if (KS8842_USE_DMA(adapter)) { + err = ks8842_alloc_dma_bufs(netdev); + + if (!err) { + /* start RX dma */ + err = __ks8842_start_new_rx_dma(netdev); + if (err) + ks8842_dealloc_dma_bufs(adapter); + } + + if (err) { + printk(KERN_WARNING DRV_NAME + ": Failed to initiate DMA, running PIO\n"); + ks8842_dealloc_dma_bufs(adapter); + adapter->dma_rx.channel = -1; + adapter->dma_tx.channel = -1; + } + } + /* reset the HW */ ks8842_reset_hw(adapter); @@ -641,6 +1029,9 @@ static int ks8842_close(struct net_device *netdev) cancel_work_sync(&adapter->timeout_work); + if (KS8842_USE_DMA(adapter)) + ks8842_dealloc_dma_bufs(adapter); + /* free the irq */ free_irq(adapter->irq, netdev); @@ -658,6 +1049,17 @@ static netdev_tx_t ks8842_xmit_frame(struct sk_buff *skb, netdev_dbg(netdev, "%s: entry\n", __func__); + if (KS8842_USE_DMA(adapter)) { + unsigned long flags; + ret = ks8842_tx_frame_dma(skb, netdev); + /* for now only allow one transfer at the time */ + spin_lock_irqsave(&adapter->lock, flags); + if (adapter->dma_tx.adesc) + netif_stop_queue(netdev); + spin_unlock_irqrestore(&adapter->lock, flags); + return ret; + } + ret = ks8842_tx_frame(skb, netdev); if (ks8842_tx_fifo_space(adapter) < netdev->mtu + 8) @@ -693,6 +1095,10 @@ static void ks8842_tx_timeout_work(struct work_struct *work) netdev_dbg(netdev, "%s: entry\n", __func__); spin_lock_irqsave(&adapter->lock, flags); + + if (KS8842_USE_DMA(adapter)) + ks8842_stop_dma(adapter); + /* disable interrupts */ ks8842_write16(adapter, 18, 0, REG_IER); ks8842_write16(adapter, 18, 0xFFFF, REG_ISR); @@ -706,6 +1112,9 @@ static void ks8842_tx_timeout_work(struct work_struct *work) ks8842_write_mac_addr(adapter, netdev->dev_addr); ks8842_update_link_status(netdev, adapter); + + if (KS8842_USE_DMA(adapter)) + __ks8842_start_new_rx_dma(netdev); } static void ks8842_tx_timeout(struct net_device *netdev) @@ -765,6 +1174,19 @@ static int __devinit ks8842_probe(struct platform_device *pdev) goto err_get_irq; } + adapter->dev = (pdev->dev.parent) ? pdev->dev.parent : &pdev->dev; + + /* DMA is only supported when accessed via timberdale */ + if (!(adapter->conf_flags & MICREL_KS884X) && pdata && + (pdata->tx_dma_channel != -1) && + (pdata->rx_dma_channel != -1)) { + adapter->dma_rx.channel = pdata->rx_dma_channel; + adapter->dma_tx.channel = pdata->tx_dma_channel; + } else { + adapter->dma_rx.channel = -1; + adapter->dma_tx.channel = -1; + } + tasklet_init(&adapter->tasklet, ks8842_tasklet, (unsigned long)netdev); spin_lock_init(&adapter->lock); |
