diff mbox series

[net] cxgb4: fix large delays in PTP synchronization

Message ID 1587376614-21111-1-git-send-email-rahul.lakkireddy@chelsio.com
State Accepted
Delegated to: David Miller
Headers show
Series [net] cxgb4: fix large delays in PTP synchronization | expand

Commit Message

Rahul Lakkireddy April 20, 2020, 9:56 a.m. UTC 
Fetching PTP sync information from mailbox is slow and can take
up to 10 milliseconds. Reduce this unnecessary delay by directly
reading the information from the corresponding registers.

Fixes: 9c33e4208bce ("cxgb4: Add PTP Hardware Clock (PHC) support")
Signed-off-by: Manoj Malviya <manojmalviya@chelsio.com>
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
---
 .../net/ethernet/chelsio/cxgb4/cxgb4_ptp.c    | 27 +++++--------------
 drivers/net/ethernet/chelsio/cxgb4/t4_regs.h  |  3 +++
 2 files changed, 9 insertions(+), 21 deletions(-)

Comments

David Miller April 20, 2020, 7:54 p.m. UTC | #1 
From: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Date: Mon, 20 Apr 2020 15:26:54 +0530

> Fetching PTP sync information from mailbox is slow and can take
> up to 10 milliseconds. Reduce this unnecessary delay by directly
> reading the information from the corresponding registers.
> 
> Fixes: 9c33e4208bce ("cxgb4: Add PTP Hardware Clock (PHC) support")
> Signed-off-by: Manoj Malviya <manojmalviya@chelsio.com>
> Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>

Applied, thank you.
diff mbox series

Patch

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_ptp.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_ptp.c
index af1f40cbccc8..f5bc996ac77d 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_ptp.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_ptp.c
@@ -311,32 +311,17 @@  static int cxgb4_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
  */
 static int cxgb4_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
 {
-	struct adapter *adapter = (struct adapter *)container_of(ptp,
-				   struct adapter, ptp_clock_info);
-	struct fw_ptp_cmd c;
+	struct adapter *adapter = container_of(ptp, struct adapter,
+					       ptp_clock_info);
 	u64 ns;
-	int err;
-
-	memset(&c, 0, sizeof(c));
-	c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
-				     FW_CMD_REQUEST_F |
-				     FW_CMD_READ_F |
-				     FW_PTP_CMD_PORTID_V(0));
-	c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
-	c.u.ts.sc = FW_PTP_SC_GET_TIME;
 
-	err = t4_wr_mbox(adapter, adapter->mbox, &c, sizeof(c), &c);
-	if (err < 0) {
-		dev_err(adapter->pdev_dev,
-			"PTP: %s error %d\n", __func__, -err);
-		return err;
-	}
+	ns = t4_read_reg(adapter, T5_PORT_REG(0, MAC_PORT_PTP_SUM_LO_A));
+	ns |= (u64)t4_read_reg(adapter,
+			       T5_PORT_REG(0, MAC_PORT_PTP_SUM_HI_A)) << 32;
 
 	/* convert to timespec*/
-	ns = be64_to_cpu(c.u.ts.tm);
 	*ts = ns_to_timespec64(ns);
-
-	return err;
+	return 0;
 }
 
 /**
diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_regs.h b/drivers/net/ethernet/chelsio/cxgb4/t4_regs.h
index bb20e50ddb84..4a9fcd6c226c 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/t4_regs.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/t4_regs.h
@@ -1906,6 +1906,9 @@ 
 
 #define MAC_PORT_CFG2_A 0x818
 
+#define MAC_PORT_PTP_SUM_LO_A 0x990
+#define MAC_PORT_PTP_SUM_HI_A 0x994
+
 #define MPS_CMN_CTL_A	0x9000
 
 #define COUNTPAUSEMCRX_S    5