ice: use read_poll_timeout_atomic in ice_read_phy_tstamp_ll_e810

The ice_read_phy_tstamp_ll_e810 function repeatedly reads the PF_SB_ATQBAL
register until the TS_LL_READ_TS bit is cleared. This is a perfect
candidate for using rd32_poll_timeout. However, the default implementation
uses a sleep-based wait. Use read_poll_timeout_atomic macro which is based
on the non-sleeping implementation and use it to replace the loop reading
in the ice_read_phy_tstamp_ll_e810 function.

Co-developed-by: Karol Kolacinski <[email protected]>
Signed-off-by: Karol Kolacinski <[email protected]>
Signed-off-by: Jacob Keller <[email protected]>
Signed-off-by: Anton Nadezhdin <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>

Author: jacob-keller

drivers/net/ethernet/intel/ice/ice_ptp_hw.c

@@ -4858,32 +4858,29 @@ static int
 ice_read_phy_tstamp_ll_e810(struct ice_hw *hw, u8 idx, u8 *hi, u32 *lo)
 {
 	u32 val;
-	u8 i;
+	int err;
 
 	/* Write TS index to read to the PF register so the FW can read it */
 	val = FIELD_PREP(TS_LL_READ_TS_IDX, idx) | TS_LL_READ_TS;
 	wr32(hw, PF_SB_ATQBAL, val);
 
 	/* Read the register repeatedly until the FW provides us the TS */
-	for (i = TS_LL_READ_RETRIES; i > 0; i--) {
-		val = rd32(hw, PF_SB_ATQBAL);
-
-		/* When the bit is cleared, the TS is ready in the register */
-		if (!(FIELD_GET(TS_LL_READ_TS, val))) {
-			/* High 8 bit value of the TS is on the bits 16:23 */
-			*hi = FIELD_GET(TS_LL_READ_TS_HIGH, val);
+	err = read_poll_timeout_atomic(rd32, val,
+				       !FIELD_GET(TS_LL_READ_TS, val), 10,
+				       TS_LL_READ_TIMEOUT, false, hw,
+				       PF_SB_ATQBAL);
+	if (err) {
+		ice_debug(hw, ICE_DBG_PTP, "Failed to read PTP timestamp using low latency read\n");
+		return err;
+	}
 
-			/* Read the low 32 bit value and set the TS valid bit */
-			*lo = rd32(hw, PF_SB_ATQBAH) | TS_VALID;
-			return 0;
-		}
+	/* High 8 bit value of the TS is on the bits 16:23 */
+	*hi = FIELD_GET(TS_LL_READ_TS_HIGH, val);
 
-		udelay(10);
-	}
+	/* Read the low 32 bit value and set the TS valid bit */
+	*lo = rd32(hw, PF_SB_ATQBAH) | TS_VALID;
 
-	/* FW failed to provide the TS in time */
-	ice_debug(hw, ICE_DBG_PTP, "Failed to read PTP timestamp using low latency read\n");
-	return -EINVAL;
+	return 0;
 }
 
 /**

drivers/net/ethernet/intel/ice/ice_ptp_hw.h

@@ -689,7 +689,7 @@ static inline bool ice_is_dual(struct ice_hw *hw)
 #define BYTES_PER_IDX_ADDR_L		4
 
 /* Tx timestamp low latency read definitions */
-#define TS_LL_READ_RETRIES		200
+#define TS_LL_READ_TIMEOUT		2000
 #define TS_LL_READ_TS_HIGH		GENMASK(23, 16)
 #define TS_LL_READ_TS_IDX		GENMASK(29, 24)
 #define TS_LL_READ_TS_INTR		BIT(30)