From: IanR778 <ianr778@zippymail.info>
Date: Wed, 8 Oct 2014 00:11:04 +0000 (+0100)
Subject: Firmware sometimes returns erroneous timestamps
X-Git-Tag: 1.4.0~1^2~3
X-Git-Url: https://jxself.org/git/?a=commitdiff_plain;h=666302581d93fe7f7c5d56d1ff05c670c37077a0;p=open-ath9k-htc-firmware.git

Firmware sometimes returns erroneous timestamps

Added proper synchronization while handling lower 32 bit and upper 32 bit parts in ar5416GetTsf64().
---

diff --git a/target_firmware/wlan/ar5416_hw.c b/target_firmware/wlan/ar5416_hw.c
index 3f3c4bc..4d2a9f4 100644
--- a/target_firmware/wlan/ar5416_hw.c
+++ b/target_firmware/wlan/ar5416_hw.c
@@ -275,14 +275,23 @@ ar5416SetInterrupts(struct ath_hal *ah, HAL_INT ints)
 /* TSF Handling */
 /****************/
 
+#define ATH9K_HTC_MAX_TSF_READ 3
+
 u_int64_t ar5416GetTsf64(struct ath_hal *ah)
 {
-        u_int64_t tsf;
-
-	tsf = ioread32_mac(AR_TSF_U32);
-	tsf = (tsf << 32) | ioread32_mac(AR_TSF_L32);
+	a_uint32_t tsf_lower, tsf_upper1, tsf_upper2;
+	a_int32_t i;
+
+	tsf_upper1 = ioread32_mac(AR_TSF_U32);
+	for (i = 0; i < ATH9K_HTC_MAX_TSF_READ; i++) {
+		tsf_lower = ioread32_mac(AR_TSF_L32);
+		tsf_upper2 = ioread32_mac(AR_TSF_U32);
+		if (tsf_upper2 == tsf_upper1)
+			break;
+		tsf_upper1 = tsf_upper2;
+	}
 
-        return tsf;
+	return (((u_int64_t)tsf_upper2 << 32) | tsf_lower);
 }
 
 /******/