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| author | Emmanuel Grumbach <emmanuel.grumbach@intel.com> | 2017-05-07 15:00:31 +0300 |
|---|---|---|
| committer | Luca Coelho <luciano.coelho@intel.com> | 2017-06-23 12:07:04 +0300 |
| commit | dcfbd67b4b8d5223d5362aac9af267387a32f568 (patch) | |
| tree | a4ec097c5ada5b733220ad9eafa3158a8f2ced34 /drivers/net/wireless/intel/iwlwifi/iwl-trans.h | |
| parent | 59df97f7223636399f425a5e76586218c48d791e (diff) | |
| download | linux-dcfbd67b4b8d5223d5362aac9af267387a32f568.tar.xz | |
iwlwifi: add a W/A for a scheduler hardware bug
In case we need to move the scheduler write pointer by
steps of 0x40, 0x80 or 0xc0, the scheduler gets stuck.
This leads to hardware error interrupts with status:
0x5A5A5A5A or alike.
In order to work around this, detect in the transport
layer that we are going to hit this case and tell iwlmvm
to increment the sequence number of the packets. This
allows to keep the requirement that the WiFi sequence
number is in sync with the index in the scheduler Tx queue
and it also allows to avoid the problematic sequence.
This means that from time to time, we will start a queue
from ssn + 1, but that shouldn't be a problem since we
don't switch to new queues for AMPDU now that we have
DQA which allows to keep the same queue while toggling
the AMPDU state.
This bug has been fixed on 9000 devices and up.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Diffstat (limited to 'drivers/net/wireless/intel/iwlwifi/iwl-trans.h')
| -rw-r--r-- | drivers/net/wireless/intel/iwlwifi/iwl-trans.h | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-trans.h b/drivers/net/wireless/intel/iwlwifi/iwl-trans.h index 2e975c0be045..57db6250a329 100644 --- a/drivers/net/wireless/intel/iwlwifi/iwl-trans.h +++ b/drivers/net/wireless/intel/iwlwifi/iwl-trans.h @@ -482,7 +482,9 @@ struct iwl_trans_txq_scd_cfg { * iwl_trans_ac_txq_enable wrapper. fw_alive must have been called before * this one. The op_mode must not configure the HCMD queue. The scheduler * configuration may be %NULL, in which case the hardware will not be - * configured. May sleep. + * configured. If true is returned, the operation mode needs to increment + * the sequence number of the packets routed to this queue because of a + * hardware scheduler bug. May sleep. * @txq_disable: de-configure a Tx queue to send AMPDUs * Must be atomic * @txq_set_shared_mode: change Tx queue shared/unshared marking @@ -544,7 +546,7 @@ struct iwl_trans_ops { void (*reclaim)(struct iwl_trans *trans, int queue, int ssn, struct sk_buff_head *skbs); - void (*txq_enable)(struct iwl_trans *trans, int queue, u16 ssn, + bool (*txq_enable)(struct iwl_trans *trans, int queue, u16 ssn, const struct iwl_trans_txq_scd_cfg *cfg, unsigned int queue_wdg_timeout); void (*txq_disable)(struct iwl_trans *trans, int queue, @@ -952,7 +954,7 @@ static inline void iwl_trans_txq_disable(struct iwl_trans *trans, int queue, trans->ops->txq_disable(trans, queue, configure_scd); } -static inline void +static inline bool iwl_trans_txq_enable_cfg(struct iwl_trans *trans, int queue, u16 ssn, const struct iwl_trans_txq_scd_cfg *cfg, unsigned int queue_wdg_timeout) @@ -961,10 +963,11 @@ iwl_trans_txq_enable_cfg(struct iwl_trans *trans, int queue, u16 ssn, if (WARN_ON_ONCE(trans->state != IWL_TRANS_FW_ALIVE)) { IWL_ERR(trans, "%s bad state = %d\n", __func__, trans->state); - return; + return false; } - trans->ops->txq_enable(trans, queue, ssn, cfg, queue_wdg_timeout); + return trans->ops->txq_enable(trans, queue, ssn, + cfg, queue_wdg_timeout); } static inline void |