package/kernel/mac80211/patches/314-ath9k-Use-tsf-offset-helper-in-ath9k_hw_reset.patch

   1 From: Benjamin Berg <benjamin.berg@open-mesh.com>
   2 Date: Mon, 4 Jul 2016 14:37:22 +0200
   3 Subject: [PATCH] ath9k: Use tsf offset helper in ath9k_hw_reset
   4
   5 These changes make ath9k_hw_reset more consistent with other places that
   6 handle the TSF value by using the same helper routine.
   7
   8 A slight improvement is to not assume that a fixed time of 1.5ms has
   9 passed for the initval writes when compared to the first write attempt.
  10 Instead the TSF value is re-calculated which will yield a higher accuracy
  11 of the restored TSF timer.
  12
  13 Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
  14 ---
  15
  16 --- a/drivers/net/wireless/ath/ath9k/hw.c
  17 +++ b/drivers/net/wireless/ath/ath9k/hw.c
  18 @@ -1832,8 +1832,9 @@ int ath9k_hw_reset(struct ath_hw *ah, st
  19         u32 saveLedState;
  20         u32 saveDefAntenna;
  21         u32 macStaId1;
  22 +       struct timespec tsf_ts;
  23 +       u32 tsf_offset;
  24         u64 tsf = 0;
  25 -       s64 usec = 0;
  26         int r;
  27         bool start_mci_reset = false;
  28         bool save_fullsleep = ah->chip_fullsleep;
  29 @@ -1877,8 +1878,8 @@ int ath9k_hw_reset(struct ath_hw *ah, st
  30         macStaId1 = REG_READ(ah, AR_STA_ID1) & AR_STA_ID1_BASE_RATE_11B;
  31
  32         /* Save TSF before chip reset, a cold reset clears it */
  33 +       getrawmonotonic(&tsf_ts);
  34         tsf = ath9k_hw_gettsf64(ah);
  35 -       usec = ktime_to_us(ktime_get_raw());
  36
  37         saveLedState = REG_READ(ah, AR_CFG_LED) &
  38                 (AR_CFG_LED_ASSOC_CTL | AR_CFG_LED_MODE_SEL |
  39 @@ -1911,8 +1912,8 @@ int ath9k_hw_reset(struct ath_hw *ah, st
  40         }
  41
  42         /* Restore TSF */
  43 -       usec = ktime_to_us(ktime_get_raw()) - usec;
  44 -       ath9k_hw_settsf64(ah, tsf + usec);
  45 +       tsf_offset = ath9k_hw_get_tsf_offset(&tsf_ts, NULL);
  46 +       ath9k_hw_settsf64(ah, tsf + tsf_offset);
  47
  48         if (AR_SREV_9280_20_OR_LATER(ah))
  49                 REG_SET_BIT(ah, AR_GPIO_INPUT_EN_VAL, AR_GPIO_JTAG_DISABLE);
  50 @@ -1932,12 +1933,11 @@ int ath9k_hw_reset(struct ath_hw *ah, st
  51         /*
  52          * Some AR91xx SoC devices frequently fail to accept TSF writes
  53          * right after the chip reset. When that happens, write a new
  54 -        * value after the initvals have been applied, with an offset
  55 -        * based on measured time difference
  56 +        * value after the initvals have been applied.
  57          */
  58         if (AR_SREV_9100(ah) && (ath9k_hw_gettsf64(ah) < tsf)) {
  59 -               tsf += 1500;
  60 -               ath9k_hw_settsf64(ah, tsf);
  61 +               tsf_offset = ath9k_hw_get_tsf_offset(&tsf_ts, NULL);
  62 +               ath9k_hw_settsf64(ah, tsf + tsf_offset);
  63         }
  64
  65         ath9k_hw_init_mfp(ah);