Both "MAC Warm Reset" and "MCI Reset Rx" will reset GPM HW write_ptr. We should check software cached write_ptr against HW write_ptr before reset. Otherwise the pending DMA data will be lost. Signed-off-by: Rajkumar Manoharan <rmanohar@xxxxxxxxxxxxxxxx> --- drivers/net/wireless/ath/ath9k/ar9003_mci.c | 18 ++++++++++++++++++ drivers/net/wireless/ath/ath9k/ar9003_mci.h | 1 + drivers/net/wireless/ath/ath9k/hw.c | 3 +++ 3 files changed, 22 insertions(+) diff --git a/drivers/net/wireless/ath/ath9k/ar9003_mci.c b/drivers/net/wireless/ath/ath9k/ar9003_mci.c index b1ced2a..96a8a5f 100644 --- a/drivers/net/wireless/ath/ath9k/ar9003_mci.c +++ b/drivers/net/wireless/ath/ath9k/ar9003_mci.c @@ -893,6 +893,9 @@ void ar9003_mci_reset(struct ath_hw *ah, bool en_int, bool is_2g, udelay(100); } + /* Check pending GPM msg before MCI Reset Rx */ + ar9003_mci_state(ah, MCI_STATE_CHECK_GPM_OFFSET, NULL); + regval |= SM(1, AR_MCI_COMMAND2_RESET_RX); REG_WRITE(ah, AR_MCI_COMMAND2, regval); udelay(1); @@ -1190,6 +1193,21 @@ u32 ar9003_mci_state(struct ath_hw *ah, u32 state_type, u32 *p_data) value = MS(REG_READ(ah, AR_MCI_GPM_1), AR_MCI_GPM_WRITE_PTR); mci->gpm_idx = value; break; + case MCI_STATE_CHECK_GPM_OFFSET: + /* + * This should only be called before "MAC Warm Reset" or + * "MCI Reset Rx". + */ + value = MS(REG_READ(ah, AR_MCI_GPM_1), AR_MCI_GPM_WRITE_PTR); + if (mci->gpm_idx == value) + break; + ath_dbg(common, MCI, + "GPM cached write pointer mismatch %d %d\n", + mci->gpm_idx, value); + mci->query_bt = true; + mci->need_flush_btinfo = true; + mci->gpm_idx = 0; + break; case MCI_STATE_NEXT_GPM_OFFSET: case MCI_STATE_LAST_GPM_OFFSET: /* diff --git a/drivers/net/wireless/ath/ath9k/ar9003_mci.h b/drivers/net/wireless/ath/ath9k/ar9003_mci.h index 10282e2..b36c885 100644 --- a/drivers/net/wireless/ath/ath9k/ar9003_mci.h +++ b/drivers/net/wireless/ath/ath9k/ar9003_mci.h @@ -190,6 +190,7 @@ enum mci_bt_state { enum mci_state_type { MCI_STATE_ENABLE, MCI_STATE_INIT_GPM_OFFSET, + MCI_STATE_CHECK_GPM_OFFSET, MCI_STATE_NEXT_GPM_OFFSET, MCI_STATE_LAST_GPM_OFFSET, MCI_STATE_BT, diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c index db3dfc9..e3ccb45 100644 --- a/drivers/net/wireless/ath/ath9k/hw.c +++ b/drivers/net/wireless/ath/ath9k/hw.c @@ -1348,6 +1348,9 @@ static bool ath9k_hw_set_reset(struct ath_hw *ah, int type) } } + if (ath9k_hw_mci_is_enabled(ah)) + ar9003_mci_state(ah, MCI_STATE_CHECK_GPM_OFFSET, NULL); + REG_WRITE(ah, AR_RTC_RC, rst_flags); REGWRITE_BUFFER_FLUSH(ah); -- 1.7.10.3 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html