[RFC PATCH net-next v4 2/2] macb: Enable 1588 support in SAMA5Dx platforms.
From: Rafal Ozieblo <hidden>
Date: 2016-12-20 16:38:54
Also in:
lkml, netdev
From: Andrei Pistirica [mailto:andrei.pistirica at microchip.com] Sent: 14 grudnia 2016 13:56
quoted hunk ↗ jump to hunk
This patch does the following: - Enable HW time stamp for the following platforms: SAMA5D2, SAMA5D3 and SAMA5D4. - HW time stamp capabilities are advertised via ethtool and macb ioctl is updated accordingly. - HW time stamp on the PTP Ethernet packets are received using the SO_TIMESTAMPING API. Where timers are obtained from the PTP event/peer registers. Note: Patch on net-next, on December 7th. Signed-off-by: Andrei Pistirica <redacted> --- Patch history: Version 1: Integration with SAMA5D2 only. This feature wasn't tested on any other platform that might use cadence/gem. Patch is not completely ported to the very latest version of net-next, and it will be after review. Version 2 modifications: - add PTP caps for SAMA5D2/3/4 platforms - and cosmetic changes Version 3 modifications: - add support for sama5D2/3/4 platforms using GEM-PTP interface. Version 4 modifications: - time stamp only PTP_V2 events - maximum adjustment value is set based on Richard's input Note: Patch on net-next, on December 14th. drivers/net/ethernet/cadence/macb.c | 168 ++++++++++++++++++++++++++++++++++-- 1 file changed, 163 insertions(+), 5 deletions(-)diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c index 538544a..8d5c976 100644 --- a/drivers/net/ethernet/cadence/macb.c +++ b/drivers/net/ethernet/cadence/macb.c@@ -714,6 +714,8 @@ static void macb_tx_interrupt(struct macb_queue *queue) /* First, update TX stats if needed */ if (skb) { + gem_ptp_do_txstamp(bp, skb); +
I think, you can not do it in that way. It will hold two locks. If you enable appropriate option in kernel (as far as I remember CONFIG_DEBUG_SPINLOCK) you will get a warning here. Please look at following call-stack: 1. macb_interrupt() // spin_lock(&bp->lock) is taken 2. macb_tx_interrupt() 3. macb_handle_txtstamp() 4. skb_tstamp_tx() 5. __skb_tstamp_tx() 6. skb_may_tx_timestamp() 7. read_lock_bh() // second lock is taken I know that those are different locks and different types. But this could lead to deadlocks. This is the reason of warning I could see. And this is the reason why I get timestamp in interrupt routine but pass it to skb outside interrupt (using circular buffer). Please, refer to this: https://lkml.org/lkml/2016/11/18/168 1. macb_tx_interrupt() 2. macb_tx_timestamp_add() and schedule_work(&queue->tx_timestamp_task) Then, outside interrupt (without holding a lock) : 1. macb_tx_timestamp_flush() 2. macb_tstamp_tx() 3. skb_tstamp_tx()
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netdev_vdbg(bp->dev, "skb %u (data %p) TX complete\n", macb_tx_ring_wrap(bp, tail), skb->data);@@ -878,6 +880,8 @@ static int gem_rx(struct macb *bp, int budget) GEM_BFEXT(RX_CSUM, ctrl) & GEM_RX_CSUM_CHECKED_MASK) skb->ip_summed = CHECKSUM_UNNECESSARY; + gem_ptp_do_rxstamp(bp, skb); + bp->stats.rx_packets++; bp->stats.rx_bytes += skb->len;@@ -2080,6 +2084,9 @@ static int macb_open(struct net_device *dev) netif_tx_start_all_queues(dev); + if (bp->ptp_info) + bp->ptp_info->ptp_init(dev); + return 0; }@@ -2101,6 +2108,9 @@ static int macb_close(struct net_device *dev) macb_free_consistent(bp); + if (bp->ptp_info) + bp->ptp_info->ptp_remove(dev); + return 0; }@@ -2374,6 +2384,133 @@ static int macb_set_ringparam(struct net_device *netdev, return 0; } +#ifdef CONFIG_MACB_USE_HWSTAMP +static unsigned int gem_get_tsu_rate(struct macb *bp) { + /* Note: TSU rate is hardwired to PCLK. */ + return clk_get_rate(bp->pclk); +}
Not exactly. There could be separate TSU clock. In my solution I check tsu_clk in DT before I decide to take pclk. But it could be change in macb_ptp_info.
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+ +static s32 gem_get_ptp_max_adj(void) +{ + return 3921508; +} + +static int gem_get_ts_info(struct net_device *dev, + struct ethtool_ts_info *info) +{ + struct macb *bp = netdev_priv(dev); + + ethtool_op_get_ts_info(dev, info); + info->so_timestamping = + SOF_TIMESTAMPING_TX_SOFTWARE | + SOF_TIMESTAMPING_RX_SOFTWARE | + SOF_TIMESTAMPING_SOFTWARE | + SOF_TIMESTAMPING_TX_HARDWARE | + SOF_TIMESTAMPING_RX_HARDWARE | + SOF_TIMESTAMPING_RAW_HARDWARE; + info->phc_index = -1; + + if (bp->ptp_clock) + info->phc_index = ptp_clock_index(bp->ptp_clock); + + return 0; +} + +static int gem_set_hwtst(struct net_device *netdev, + struct ifreq *ifr, int cmd) +{ + struct hwtstamp_config config; + struct macb *priv = netdev_priv(netdev); + u32 regval; + + netdev_vdbg(netdev, "macb_hwtstamp_ioctl\n"); + + if (copy_from_user(&config, ifr->ifr_data, sizeof(config))) + return -EFAULT; + + /* reserved for future extensions */ + if (config.flags) + return -EINVAL; + + switch (config.tx_type) { + case HWTSTAMP_TX_OFF: + priv->hwts_tx_en = false; + break; + case HWTSTAMP_TX_ON: + priv->hwts_tx_en = true; + break; + default: + return -ERANGE; + } + + switch (config.rx_filter) { + case HWTSTAMP_FILTER_NONE: + if (priv->hwts_rx_en) + priv->hwts_rx_en = false; + break; + case HWTSTAMP_FILTER_PTP_V2_L4_EVENT: + case HWTSTAMP_FILTER_PTP_V2_L2_EVENT: + case HWTSTAMP_FILTER_PTP_V2_L2_SYNC: + case HWTSTAMP_FILTER_PTP_V2_L4_SYNC: + case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ: + case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ: + case HWTSTAMP_FILTER_PTP_V2_EVENT: + case HWTSTAMP_FILTER_PTP_V2_SYNC: + case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ: + config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT; + regval = macb_readl(priv, NCR); + macb_writel(priv, NCR, (regval | MACB_BIT(SRTSM))); + + if (!priv->hwts_rx_en) + priv->hwts_rx_en = true; + break; + default: + config.rx_filter = HWTSTAMP_FILTER_NONE; + return -ERANGE; + } + + return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ? + -EFAULT : 0; +} + +static int gem_get_hwtst(struct net_device *netdev, + struct ifreq *ifr) +{ + struct hwtstamp_config config; + struct macb *priv = netdev_priv(netdev); + + config.flags = 0; + config.tx_type = priv->hwts_tx_en ? HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF; + config.rx_filter = (priv->hwts_rx_en ? + HWTSTAMP_FILTER_ALL : HWTSTAMP_FILTER_NONE); + + return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ? + -EFAULT : 0; +} + +static struct macb_ptp_info gem_ptp_info = { + .ptp_init = gem_ptp_init, + .ptp_remove = gem_ptp_remove, + .get_ptp_max_adj = gem_get_ptp_max_adj, + .get_tsu_rate = gem_get_tsu_rate, + .get_ts_info = gem_get_ts_info, + .get_hwtst = gem_get_hwtst, + .set_hwtst = gem_set_hwtst, +}; +#endif + +static int macb_get_ts_info(struct net_device *netdev, + struct ethtool_ts_info *info) +{ + struct macb *bp = netdev_priv(netdev); + + if (bp->ptp_info) + return bp->ptp_info->get_ts_info(netdev, info); + + return ethtool_op_get_ts_info(netdev, info); } + static const struct ethtool_ops macb_ethtool_ops = { .get_regs_len = macb_get_regs_len, .get_regs = macb_get_regs,@@ -2391,7 +2528,7 @@ static const struct ethtool_ops gem_ethtool_ops = { .get_regs_len = macb_get_regs_len, .get_regs = macb_get_regs, .get_link = ethtool_op_get_link, - .get_ts_info = ethtool_op_get_ts_info, + .get_ts_info = macb_get_ts_info, .get_ethtool_stats = gem_get_ethtool_stats, .get_strings = gem_get_ethtool_strings, .get_sset_count = gem_get_sset_count,@@ -2404,6 +2541,7 @@ static const struct ethtool_ops gem_ethtool_ops = { static int macb_ioctl(struct net_device *dev, struct ifreq *rq, int cmd) { struct phy_device *phydev = dev->phydev; + struct macb *bp = netdev_priv(dev); if (!netif_running(dev)) return -EINVAL;@@ -2411,7 +2549,20 @@ static int macb_ioctl(struct net_device *dev, struct ifreq *rq, int cmd) if (!phydev) return -ENODEV; - return phy_mii_ioctl(phydev, rq, cmd); + switch (cmd) { + case SIOCSHWTSTAMP: + if (bp->ptp_info) + return bp->ptp_info->set_hwtst(dev, rq, cmd); + + return -EOPNOTSUPP; + case SIOCGHWTSTAMP: + if (bp->ptp_info) + return bp->ptp_info->get_hwtst(dev, rq); + + return -EOPNOTSUPP; + default: + return phy_mii_ioctl(phydev, rq, cmd); + } } static int macb_set_features(struct net_device *netdev, @@ -2485,6 +2636,12 @@ static void macb_configure_caps(struct macb *bp, dcfg = gem_readl(bp, DCFG2); if ((dcfg & (GEM_BIT(RX_PKT_BUFF) | GEM_BIT(TX_PKT_BUFF))) == 0) bp->caps |= MACB_CAPS_FIFO_MODE; + + /* iff HWSTAMP is configure and gem has the capability */ #ifdef +CONFIG_MACB_USE_HWSTAMP + if (gem_has_ptp(bp)) + bp->ptp_info = &gem_ptp_info; +#endif } dev_dbg(&bp->pdev->dev, "Cadence caps 0x%08x\n", bp->caps); @@ -3041,7 +3198,7 @@ static const struct macb_config pc302gem_config = { }; static const struct macb_config sama5d2_config = { - .caps = MACB_CAPS_USRIO_DEFAULT_IS_MII_GMII, + .caps = MACB_CAPS_USRIO_DEFAULT_IS_MII_GMII | MACB_CAPS_GEM_HAS_PTP,
There are many IP cores with many configuration. If it is possible, capabilities should be read from IP directly. And it is possible in that case: Design Configuration Register 5 (0x290) bit 8: tsu There is now PTP hardware support without that bit.
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.dma_burst_length = 16, .clk_init = macb_clk_init, .init = macb_init,@@ -3049,14 +3206,15 @@ static const struct macb_config sama5d2_config = { static const struct macb_config sama5d3_config = { .caps = MACB_CAPS_SG_DISABLED | MACB_CAPS_GIGABIT_MODE_AVAILABLE - | MACB_CAPS_USRIO_DEFAULT_IS_MII_GMII, + | MACB_CAPS_USRIO_DEFAULT_IS_MII_GMII + | MACB_CAPS_GEM_HAS_PTP, .dma_burst_length = 16, .clk_init = macb_clk_init, .init = macb_init, }; static const struct macb_config sama5d4_config = { - .caps = MACB_CAPS_USRIO_DEFAULT_IS_MII_GMII, + .caps = MACB_CAPS_USRIO_DEFAULT_IS_MII_GMII | MACB_CAPS_GEM_HAS_PTP, .dma_burst_length = 4, .clk_init = macb_clk_init, .init = macb_init, --2.7.4
In macb_start_xmit() there is also invoked skb_tx_timestamp() for software timestamping. I think, it should be disabled if you do hardware timestamping. Best regards, Rafal Ozieblo | Firmware System Engineer, www.cadence.com