[Intel-wired-lan] [next-queue PATCH v2 3/5] igc: Add support for TX timestamping
Vinicius Costa Gomes
vinicius.gomes at intel.com
Wed Nov 27 01:04:33 UTC 2019
This adds support for timestamping packets being transmitted.
Based on the code from i210. The basic differences is that i225 has 4
registers to store the transmit timestamps (i210 has one). Right now,
we only support retrieving from one register, support for using the
other registers will be added later.
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes at intel.com>
---
drivers/net/ethernet/intel/igc/igc.h | 2 +
drivers/net/ethernet/intel/igc/igc_defines.h | 14 +++
drivers/net/ethernet/intel/igc/igc_main.c | 49 +++++++++++
drivers/net/ethernet/intel/igc/igc_ptp.c | 92 ++++++++++++++++++++
4 files changed, 157 insertions(+)
diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
index 686fe6d9dae6..228a9179fd06 100644
--- a/drivers/net/ethernet/intel/igc/igc.h
+++ b/drivers/net/ethernet/intel/igc/igc.h
@@ -556,6 +556,8 @@ void igc_ptp_rx_pktstamp(struct igc_q_vector *q_vector, void *va,
struct sk_buff *skb);
int igc_ptp_set_ts_config(struct net_device *netdev, struct ifreq *ifr);
int igc_ptp_get_ts_config(struct net_device *netdev, struct ifreq *ifr);
+void igc_ptp_tx_hang(struct igc_adapter *adapter);
+
#define igc_rx_pg_size(_ring) (PAGE_SIZE << igc_rx_pg_order(_ring))
#define IGC_TXD_DCMD (IGC_ADVTXD_DCMD_EOP | IGC_ADVTXD_DCMD_RS)
diff --git a/drivers/net/ethernet/intel/igc/igc_defines.h b/drivers/net/ethernet/intel/igc/igc_defines.h
index e1f23f89b6a9..e978fd484fc8 100644
--- a/drivers/net/ethernet/intel/igc/igc_defines.h
+++ b/drivers/net/ethernet/intel/igc/igc_defines.h
@@ -370,10 +370,24 @@
#define IGC_TSYNCRXCFG_PTP_V1_SYNC_MESSAGE 0x00
#define IGC_TSYNCRXCFG_PTP_V1_DELAY_REQ_MESSAGE 0x01
+/* Immediate Interrupt Receive */
+#define IGC_IMIR_CLEAR_MASK 0xF001FFFF /* IMIR Reg Clear Mask */
+#define IGC_IMIR_PORT_BYPASS 0x20000 /* IMIR Port Bypass Bit */
+#define IGC_IMIR_PRIORITY_SHIFT 29 /* IMIR Priority Shift */
+#define IGC_IMIREXT_CLEAR_MASK 0x7FFFF /* IMIREXT Reg Clear Mask */
+
/* Immediate Interrupt Receive Extended */
#define IGC_IMIREXT_CTRL_BP 0x00080000 /* Bypass check of ctrl bits */
#define IGC_IMIREXT_SIZE_BP 0x00001000 /* Packet size bypass */
+/* Time Sync Transmit Control bit definitions */
+#define IGC_TSYNCTXCTL_VALID 0x00000001 /* Tx timestamp valid */
+#define IGC_TSYNCTXCTL_ENABLED 0x00000010 /* enable Tx timestamping */
+#define IGC_TSYNCTXCTL_MAX_ALLOWED_DLY_MASK 0x0000F000 /* max delay */
+#define IGC_TSYNCTXCTL_SYNC_COMP_ERR 0x20000000 /* sync err */
+#define IGC_TSYNCTXCTL_SYNC_COMP 0x40000000 /* sync complete */
+#define IGC_TSYNCTXCTL_START_SYNC 0x80000000 /* initiate sync */
+
/* Receive Checksum Control */
#define IGC_RXCSUM_CRCOFL 0x00000800 /* CRC32 offload enable */
#define IGC_RXCSUM_PCSD 0x00002000 /* packet checksum disabled */
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index f6319cb6b5ca..26ca3cfd5af2 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -960,6 +960,11 @@ static inline int igc_maybe_stop_tx(struct igc_ring *tx_ring, const u16 size)
return __igc_maybe_stop_tx(tx_ring, size);
}
+#define IGC_SET_FLAG(_input, _flag, _result) \
+ (((_flag) <= (_result)) ? \
+ ((u32)((_input) & (_flag)) * ((_result) / (_flag))) : \
+ ((u32)((_input) & (_flag)) / ((_flag) / (_result))))
+
static u32 igc_tx_cmd_type(struct sk_buff *skb, u32 tx_flags)
{
/* set type for advanced descriptor with frame checksum insertion */
@@ -967,6 +972,10 @@ static u32 igc_tx_cmd_type(struct sk_buff *skb, u32 tx_flags)
IGC_ADVTXD_DCMD_DEXT |
IGC_ADVTXD_DCMD_IFCS;
+ /* set timestamp bit if present */
+ cmd_type |= IGC_SET_FLAG(tx_flags, IGC_TX_FLAGS_TSTAMP,
+ (IGC_ADVTXD_MAC_TSTAMP));
+
return cmd_type;
}
@@ -1165,6 +1174,26 @@ static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
first->bytecount = skb->len;
first->gso_segs = 1;
+ if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)) {
+ struct igc_adapter *adapter = netdev_priv(tx_ring->netdev);
+
+ /* FIXME: add support for retrieving timestamps from
+ * the other timer registers before skipping the
+ * timestamping request.
+ */
+ if (adapter->tstamp_config.tx_type == HWTSTAMP_TX_ON &&
+ !test_and_set_bit_lock(__IGC_PTP_TX_IN_PROGRESS,
+ &adapter->state)) {
+ skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
+ tx_flags |= IGC_TX_FLAGS_TSTAMP;
+
+ adapter->ptp_tx_skb = skb_get(skb);
+ adapter->ptp_tx_start = jiffies;
+ } else {
+ adapter->tx_hwtstamp_skipped++;
+ }
+ }
+
/* record initial flags and protocol */
first->tx_flags = tx_flags;
first->protocol = protocol;
@@ -2765,6 +2794,21 @@ static void igc_set_rx_mode(struct net_device *netdev)
wr32(IGC_RLPML, rlpml);
}
+static void igc_tsync_interrupt(struct igc_adapter *adapter)
+{
+ struct igc_hw *hw = &adapter->hw;
+ u32 ack = 0, tsicr = rd32(IGC_TSICR);
+
+ if (tsicr & IGC_TSICR_TXTS) {
+ /* retrieve hardware timestamp */
+ schedule_work(&adapter->ptp_tx_work);
+ ack |= IGC_TSICR_TXTS;
+ }
+
+ /* acknowledge the interrupts */
+ wr32(IGC_TSICR, ack);
+}
+
/**
* igc_msix_other - msix other interrupt handler
* @irq: interrupt number
@@ -2792,6 +2836,9 @@ static irqreturn_t igc_msix_other(int irq, void *data)
mod_timer(&adapter->watchdog_timer, jiffies + 1);
}
+ if (icr & IGC_ICR_TS)
+ igc_tsync_interrupt(adapter);
+
wr32(IGC_EIMS, adapter->eims_other);
return IRQ_HANDLED;
@@ -3295,6 +3342,8 @@ static void igc_watchdog_task(struct work_struct *work)
wr32(IGC_ICS, IGC_ICS_RXDMT0);
}
+ igc_ptp_tx_hang(adapter);
+
/* Reset the timer */
if (!test_bit(__IGC_DOWN, &adapter->state)) {
if (adapter->flags & IGC_FLAG_NEED_LINK_UPDATE)
diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/ethernet/intel/igc/igc_ptp.c
index b39d14d40ec9..b63a03157ec1 100644
--- a/drivers/net/ethernet/intel/igc/igc_ptp.c
+++ b/drivers/net/ethernet/intel/igc/igc_ptp.c
@@ -284,6 +284,12 @@ static void igc_ptp_enable_tstamp_all_rxqueues(struct igc_adapter *adapter,
* @adapter: networking device structure
* @config: hwtstamp configuration
*
+ * Outgoing time stamping can be enabled and disabled. Play nice and
+ * disable it when requested, although it shouldn't case any overhead
+ * when no packet needs it. At most one packet in the queue may be
+ * marked for time stamping, otherwise it would be impossible to tell
+ * for sure to which packet the hardware time stamp belongs.
+ *
* Incoming time stamping has to be configured via the hardware
* filters. Not all combinations are supported, in particular event
* type has to be specified. Matching the kind of event packet is
@@ -295,6 +301,7 @@ static int igc_ptp_set_timestamp_mode(struct igc_adapter *adapter,
struct hwtstamp_config *config)
{
struct igc_hw *hw = &adapter->hw;
+ u32 tsync_tx_ctl = IGC_TSYNCTXCTL_ENABLED;
u32 tsync_rx_ctl = IGC_TSYNCRXCTL_ENABLED;
u32 tsync_rx_cfg = 0;
bool is_l4 = false;
@@ -305,6 +312,15 @@ static int igc_ptp_set_timestamp_mode(struct igc_adapter *adapter,
if (config->flags)
return -EINVAL;
+ switch (config->tx_type) {
+ case HWTSTAMP_TX_OFF:
+ tsync_tx_ctl = 0;
+ case HWTSTAMP_TX_ON:
+ break;
+ default:
+ return -ERANGE;
+ }
+
switch (config->rx_filter) {
case HWTSTAMP_FILTER_NONE:
tsync_rx_ctl = 0;
@@ -368,6 +384,15 @@ static int igc_ptp_set_timestamp_mode(struct igc_adapter *adapter,
}
}
+ if (tsync_tx_ctl)
+ tsync_tx_ctl = IGC_TSYNCTXCTL_ENABLED;
+
+ /* enable/disable TX */
+ regval = rd32(IGC_TSYNCTXCTL);
+ regval &= ~IGC_TSYNCTXCTL_ENABLED;
+ regval |= tsync_tx_ctl;
+ wr32(IGC_TSYNCTXCTL, regval);
+
/* enable/disable RX */
regval = rd32(IGC_TSYNCRXCTL);
regval &= ~(IGC_TSYNCRXCTL_ENABLED | IGC_TSYNCRXCTL_TYPE_MASK);
@@ -442,8 +467,75 @@ void igc_ptp_tx_hang(struct igc_adapter *adapter)
}
}
+/**
+ * igc_ptp_tx_hwtstamp - utility function which checks for TX time stamp
+ * @adapter: Board private structure.
+ *
+ * If we were asked to do hardware stamping and such a time stamp is
+ * available, then it must have been for this skb here because we only
+ * allow only one such packet into the queue.
+ */
+static void igc_ptp_tx_hwtstamp(struct igc_adapter *adapter)
+{
+ struct sk_buff *skb = adapter->ptp_tx_skb;
+ struct skb_shared_hwtstamps shhwtstamps;
+ struct igc_hw *hw = &adapter->hw;
+ u64 regval;
+
+ regval = rd32(IGC_TXSTMPL);
+ regval |= (u64)rd32(IGC_TXSTMPH) << 32;
+ igc_ptp_systim_to_hwtstamp(adapter, &shhwtstamps, regval);
+
+ /* Clear the lock early before calling skb_tstamp_tx so that
+ * applications are not woken up before the lock bit is clear. We use
+ * a copy of the skb pointer to ensure other threads can't change it
+ * while we're notifying the stack.
+ */
+ adapter->ptp_tx_skb = NULL;
+ clear_bit_unlock(__IGC_PTP_TX_IN_PROGRESS, &adapter->state);
+
+ /* Notify the stack and free the skb after we've unlocked */
+ skb_tstamp_tx(skb, &shhwtstamps);
+ dev_kfree_skb_any(skb);
+}
+
+/**
+ * igc_ptp_tx_work
+ * @work: pointer to work struct
+ *
+ * This work function polls the TSYNCTXCTL valid bit to determine when a
+ * timestamp has been taken for the current stored skb.
+ */
void igc_ptp_tx_work(struct work_struct *work)
{
+ struct igc_adapter *adapter = container_of(work, struct igc_adapter,
+ ptp_tx_work);
+ struct igc_hw *hw = &adapter->hw;
+ u32 tsynctxctl;
+
+ if (!adapter->ptp_tx_skb)
+ return;
+
+ if (time_is_before_jiffies(adapter->ptp_tx_start +
+ IGC_PTP_TX_TIMEOUT)) {
+ dev_kfree_skb_any(adapter->ptp_tx_skb);
+ adapter->ptp_tx_skb = NULL;
+ clear_bit_unlock(__IGC_PTP_TX_IN_PROGRESS, &adapter->state);
+ adapter->tx_hwtstamp_timeouts++;
+ /* Clear the tx valid bit in TSYNCTXCTL register to enable
+ * interrupt
+ */
+ rd32(IGC_TXSTMPH);
+ dev_warn(&adapter->pdev->dev, "clearing Tx timestamp hang\n");
+ return;
+ }
+
+ tsynctxctl = rd32(IGC_TSYNCTXCTL);
+ if (tsynctxctl & IGC_TSYNCTXCTL_VALID)
+ igc_ptp_tx_hwtstamp(adapter);
+ else
+ /* reschedule to check later */
+ schedule_work(&adapter->ptp_tx_work);
}
/**
--
2.24.0
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