iwlwifi: add comments to Tx commands

Add comments to Tx commands

Clean up unused definitions in iwl-3945-commands.h

Signed-off-by: Ben Cahill <ben.m.cahill@intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/iwlwifi/iwl-3945-commands.h b/drivers/net/wireless/iwlwifi/iwl-3945-commands.h
index 4885971a1536c2b2731eeccb1d581becf388d177..3cac2c8ccf6061df84904fa8c0bb29f8d2214933 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-3945-commands.h
+++ b/drivers/net/wireless/iwlwifi/iwl-3945-commands.h
@@ -743,36 +743,86 @@ struct iwl4965_rx_mpdu_res_start {
  * (5)
  * Tx Commands & Responses:
  *
  * (5)
  * Tx Commands & Responses:
  *

+ * Driver must place each REPLY_TX command into one of the prioritized Tx
+ * queues in host DRAM, shared between driver and device.  When the device's
+ * Tx scheduler and uCode are preparing to transmit, the device pulls the
+ * Tx command over the PCI bus via one of the device's Tx DMA channels,
+ * to fill an internal FIFO from which data will be transmitted.
+ *
+ * uCode handles all timing and protocol related to control frames
+ * (RTS/CTS/ACK), based on flags in the Tx command.
+ *
+ * uCode handles retrying Tx when an ACK is expected but not received.
+ * This includes trying lower data rates than the one requested in the Tx
+ * command, as set up by the REPLY_RATE_SCALE (for 3945) or
+ * REPLY_TX_LINK_QUALITY_CMD (4965).
+ *
+ * Driver sets up transmit power for various rates via REPLY_TX_PWR_TABLE_CMD.
+ * This command must be executed after every RXON command, before Tx can occur.

  *****************************************************************************/
 
  *****************************************************************************/
 

-/* Tx flags */
+/* REPLY_TX Tx flags field */
+
+/* 1: Use Request-To-Send protocol before this frame.
+ * Mutually exclusive vs. TX_CMD_FLG_CTS_MSK. */

 #define TX_CMD_FLG_RTS_MSK __constant_cpu_to_le32(1 << 1)
 #define TX_CMD_FLG_RTS_MSK __constant_cpu_to_le32(1 << 1)

+
+/* 1: Transmit Clear-To-Send to self before this frame.
+ * Driver should set this for AUTH/DEAUTH/ASSOC-REQ/REASSOC mgmnt frames.
+ * Mutually exclusive vs. TX_CMD_FLG_RTS_MSK. */

 #define TX_CMD_FLG_CTS_MSK __constant_cpu_to_le32(1 << 2)
 #define TX_CMD_FLG_CTS_MSK __constant_cpu_to_le32(1 << 2)

+
+/* 1: Expect ACK from receiving station
+ * 0: Don't expect ACK (MAC header's duration field s/b 0)
+ * Set this for unicast frames, but not broadcast/multicast. */

 #define TX_CMD_FLG_ACK_MSK __constant_cpu_to_le32(1 << 3)
 #define TX_CMD_FLG_ACK_MSK __constant_cpu_to_le32(1 << 3)

+
+/* 1: Use rate scale table (see REPLY_TX_LINK_QUALITY_CMD).
+ *    Tx command's initial_rate_index indicates first rate to try;
+ *    uCode walks through table for additional Tx attempts.
+ * 0: Use Tx rate/MCS from Tx command's rate_n_flags field.
+ *    This rate will be used for all Tx attempts; it will not be scaled. */

 #define TX_CMD_FLG_STA_RATE_MSK __constant_cpu_to_le32(1 << 4)
 #define TX_CMD_FLG_STA_RATE_MSK __constant_cpu_to_le32(1 << 4)

+
+/* 1: Expect immediate block-ack.
+ * Set when Txing a block-ack request frame.  Also set TX_CMD_FLG_ACK_MSK. */

 #define TX_CMD_FLG_IMM_BA_RSP_MASK  __constant_cpu_to_le32(1 << 6)
 #define TX_CMD_FLG_IMM_BA_RSP_MASK  __constant_cpu_to_le32(1 << 6)

+
+/* 1: Frame requires full Tx-Op protection.
+ * Set this if either RTS or CTS Tx Flag gets set. */

 #define TX_CMD_FLG_FULL_TXOP_PROT_MSK __constant_cpu_to_le32(1 << 7)
 #define TX_CMD_FLG_FULL_TXOP_PROT_MSK __constant_cpu_to_le32(1 << 7)

+
+/* Tx antenna selection field; used only for 3945, reserved (0) for 4965.
+ * Set field to "0" to allow 3945 uCode to select antenna (normal usage). */

 #define TX_CMD_FLG_ANT_SEL_MSK __constant_cpu_to_le32(0xf00)
 #define TX_CMD_FLG_ANT_A_MSK __constant_cpu_to_le32(1 << 8)
 #define TX_CMD_FLG_ANT_B_MSK __constant_cpu_to_le32(1 << 9)
 
 #define TX_CMD_FLG_ANT_SEL_MSK __constant_cpu_to_le32(0xf00)
 #define TX_CMD_FLG_ANT_A_MSK __constant_cpu_to_le32(1 << 8)
 #define TX_CMD_FLG_ANT_B_MSK __constant_cpu_to_le32(1 << 9)
 

-/* ucode ignores BT priority for this frame */
+/* 1: Ignore Bluetooth priority for this frame.
+ * 0: Delay Tx until Bluetooth device is done (normal usage). */

 #define TX_CMD_FLG_BT_DIS_MSK __constant_cpu_to_le32(1 << 12)
 
 #define TX_CMD_FLG_BT_DIS_MSK __constant_cpu_to_le32(1 << 12)
 

-/* ucode overrides sequence control */
+/* 1: uCode overrides sequence control field in MAC header.
+ * 0: Driver provides sequence control field in MAC header.
+ * Set this for management frames, non-QOS data frames, non-unicast frames,
+ * and also in Tx command embedded in REPLY_SCAN_CMD for active scans. */

 #define TX_CMD_FLG_SEQ_CTL_MSK __constant_cpu_to_le32(1 << 13)
 
 #define TX_CMD_FLG_SEQ_CTL_MSK __constant_cpu_to_le32(1 << 13)
 

-/* signal that this frame is non-last MPDU */
+/* 1: This frame is non-last MPDU; more fragments are coming.
+ * 0: Last fragment, or not using fragmentation. */

 #define TX_CMD_FLG_MORE_FRAG_MSK __constant_cpu_to_le32(1 << 14)
 
 #define TX_CMD_FLG_MORE_FRAG_MSK __constant_cpu_to_le32(1 << 14)
 

-/* calculate TSF in outgoing frame */
+/* 1: uCode calculates and inserts Timestamp Function (TSF) in outgoing frame.
+ * 0: No TSF required in outgoing frame.
+ * Set this for transmitting beacons and probe responses. */

 #define TX_CMD_FLG_TSF_MSK __constant_cpu_to_le32(1 << 16)
 
 #define TX_CMD_FLG_TSF_MSK __constant_cpu_to_le32(1 << 16)
 

-/* activate TX calibration. */
-#define TX_CMD_FLG_CALIB_MSK __constant_cpu_to_le32(1 << 17)
-
-/* signals that 2 bytes pad was inserted
-   after the MAC header */
+/* 1: Driver inserted 2 bytes pad after the MAC header, for (required) dword
+ *    alignment of frame's payload data field.
+ * 0: No pad
+ * Set this for MAC headers with 26 or 30 bytes, i.e. those with QOS or ADDR4
+ * field (but not both).  Driver must align frame data (i.e. data following
+ * MAC header) to DWORD boundary. */

 #define TX_CMD_FLG_MH_PAD_MSK __constant_cpu_to_le32(1 << 20)
 
 /* HCCA-AP - disable duration overwriting. */
 #define TX_CMD_FLG_MH_PAD_MSK __constant_cpu_to_le32(1 << 20)
 
 /* HCCA-AP - disable duration overwriting. */


@@ -788,24 +838,34 @@ struct iwl4965_rx_mpdu_res_start {
 #define TX_CMD_SEC_SHIFT       6
 #define TX_CMD_SEC_KEY128      0x08
 
 #define TX_CMD_SEC_SHIFT       6
 #define TX_CMD_SEC_KEY128      0x08
 

-/*
- * TX command Frame life time
- */
-
-struct iwl3945_dram_scratch {
-       u8 try_cnt;
-       u8 bt_kill_cnt;
-       __le16 reserved;
-} __attribute__ ((packed));
-

 /*
  * REPLY_TX = 0x1c (command)
  */
 struct iwl3945_tx_cmd {
 /*
  * REPLY_TX = 0x1c (command)
  */
 struct iwl3945_tx_cmd {

+       /*
+        * MPDU byte count:
+        * MAC header (24/26/30/32 bytes) + 2 bytes pad if 26/30 header size,
+        * + 8 byte IV for CCM or TKIP (not used for WEP)
+        * + Data payload
+        * + 8-byte MIC (not used for CCM/WEP)
+        * NOTE:  Does not include Tx command bytes, post-MAC pad bytes,
+        *        MIC (CCM) 8 bytes, ICV (WEP/TKIP/CKIP) 4 bytes, CRC 4 bytes.i
+        * Range: 14-2342 bytes.
+        */

        __le16 len;
        __le16 len;

+
+       /*
+        * MPDU or MSDU byte count for next frame.
+        * Used for fragmentation and bursting, but not 11n aggregation.
+        * Same as "len", but for next frame.  Set to 0 if not applicable.
+        */

        __le16 next_frame_len;
        __le16 next_frame_len;

-       __le32 tx_flags;
+
+       __le32 tx_flags;        /* TX_CMD_FLG_* */
+

        u8 rate;
        u8 rate;

+
+       /* Index of recipient station in uCode's station table */

        u8 sta_id;
        u8 tid_tspec;
        u8 sec_ctl;
        u8 sta_id;
        u8 tid_tspec;
        u8 sec_ctl;


@@ -827,7 +887,17 @@ struct iwl3945_tx_cmd {
                __le16 pm_frame_timeout;
                __le16 attempt_duration;
        } timeout;
                __le16 pm_frame_timeout;
                __le16 attempt_duration;
        } timeout;

+
+       /*
+        * Duration of EDCA burst Tx Opportunity, in 32-usec units.
+        * Set this if txop time is not specified by HCCA protocol (e.g. by AP).
+        */

        __le16 driver_txop;
        __le16 driver_txop;

+
+       /*
+        * MAC header goes here, followed by 2 bytes padding if MAC header
+        * length is 26 or 30 bytes, followed by payload data
+        */

        u8 payload[0];
        struct ieee80211_hdr hdr[0];
 } __attribute__ ((packed));
        u8 payload[0];
        struct ieee80211_hdr hdr[0];
 } __attribute__ ((packed));


@@ -899,37 +969,6 @@ enum {
        TX_ABORT_REQUIRED_MSK = 0x80000000,     /* bits 31:31 */
 };
 
        TX_ABORT_REQUIRED_MSK = 0x80000000,     /* bits 31:31 */
 };
 

-/* *******************************
- * TX aggregation state
- ******************************* */
-
-enum {
-       AGG_TX_STATE_TRANSMITTED = 0x00,
-       AGG_TX_STATE_UNDERRUN_MSK = 0x01,
-       AGG_TX_STATE_BT_PRIO_MSK = 0x02,
-       AGG_TX_STATE_FEW_BYTES_MSK = 0x04,
-       AGG_TX_STATE_ABORT_MSK = 0x08,
-       AGG_TX_STATE_LAST_SENT_TTL_MSK = 0x10,
-       AGG_TX_STATE_LAST_SENT_TRY_CNT_MSK = 0x20,
-       AGG_TX_STATE_LAST_SENT_BT_KILL_MSK = 0x40,
-       AGG_TX_STATE_SCD_QUERY_MSK = 0x80,
-       AGG_TX_STATE_TEST_BAD_CRC32_MSK = 0x100,
-       AGG_TX_STATE_RESPONSE_MSK = 0x1ff,
-       AGG_TX_STATE_DUMP_TX_MSK = 0x200,
-       AGG_TX_STATE_DELAY_TX_MSK = 0x400
-};
-
-#define AGG_TX_STATE_LAST_SENT_MSK \
-(AGG_TX_STATE_LAST_SENT_TTL_MSK | \
- AGG_TX_STATE_LAST_SENT_TRY_CNT_MSK | \
- AGG_TX_STATE_LAST_SENT_BT_KILL_MSK)
-
-#define AGG_TX_STATE_TRY_CNT_POS 12
-#define AGG_TX_STATE_TRY_CNT_MSK 0xf000
-
-#define AGG_TX_STATE_SEQ_NUM_POS 16
-#define AGG_TX_STATE_SEQ_NUM_MSK 0xffff0000
-

 /*
  * REPLY_TX = 0x1c (response)
  */
 /*
  * REPLY_TX = 0x1c (response)
  */


@@ -939,23 +978,7 @@ struct iwl3945_tx_resp {
        u8 bt_kill_count;
        u8 rate;
        __le32 wireless_media_time;
        u8 bt_kill_count;
        u8 rate;
        __le32 wireless_media_time;

-       __le32 status;  /* TX status (for aggregation status of 1st frame) */
-} __attribute__ ((packed));
-
-/*
- * REPLY_COMPRESSED_BA = 0xc5 (response only, not a command)
- */
-struct iwl3945_compressed_ba_resp {
-       __le32 sta_addr_lo32;
-       __le16 sta_addr_hi16;
-       __le16 reserved;
-       u8 sta_id;
-       u8 tid;
-       __le16 ba_seq_ctl;
-       __le32 ba_bitmap0;
-       __le32 ba_bitmap1;
-       __le16 scd_flow;
-       __le16 scd_ssn;
+       __le32 status;          /* TX status */

 } __attribute__ ((packed));
 
 /*
 } __attribute__ ((packed));
 
 /*

diff --git a/drivers/net/wireless/iwlwifi/iwl-4965-commands.h b/drivers/net/wireless/iwlwifi/iwl-4965-commands.h
index 44addea5062b7eb087729d4cce424e8b6035831b..cbe91dbe760c4787b1c5c3da07609e2f750703c2 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-4965-commands.h
+++ b/drivers/net/wireless/iwlwifi/iwl-4965-commands.h
@@ -937,8 +937,8 @@ struct iwl4965_rx_phy_res {
        __le16 channel;         /* channel number */
        __le16 non_cfg_phy[RX_RES_PHY_CNT];     /* upto 14 phy entries */
        __le32 reserved2;
        __le16 channel;         /* channel number */
        __le16 non_cfg_phy[RX_RES_PHY_CNT];     /* upto 14 phy entries */
        __le32 reserved2;

-       __le32 rate_n_flags;
-       __le16 byte_count;              /* frame's byte-count */
+       __le32 rate_n_flags;    /* RATE_MCS_* */
+       __le16 byte_count;      /* frame's byte-count */

        __le16 reserved3;
 } __attribute__ ((packed));
 
        __le16 reserved3;
 } __attribute__ ((packed));
 


@@ -952,41 +952,96 @@ struct iwl4965_rx_mpdu_res_start {
  * (5)
  * Tx Commands & Responses:
  *
  * (5)
  * Tx Commands & Responses:
  *

+ * Driver must place each REPLY_TX command into one of the prioritized Tx
+ * queues in host DRAM, shared between driver and device (see comments for
+ * SCD registers and Tx/Rx Queues).  When the device's Tx scheduler and uCode
+ * are preparing to transmit, the device pulls the Tx command over the PCI
+ * bus via one of the device's Tx DMA channels, to fill an internal FIFO
+ * from which data will be transmitted.
+ *
+ * uCode handles all timing and protocol related to control frames
+ * (RTS/CTS/ACK), based on flags in the Tx command.  uCode and Tx scheduler
+ * handle reception of block-acks; uCode updates the host driver via
+ * REPLY_COMPRESSED_BA (4965).
+ *
+ * uCode handles retrying Tx when an ACK is expected but not received.
+ * This includes trying lower data rates than the one requested in the Tx
+ * command, as set up by the REPLY_RATE_SCALE (for 3945) or
+ * REPLY_TX_LINK_QUALITY_CMD (4965).
+ *
+ * Driver sets up transmit power for various rates via REPLY_TX_PWR_TABLE_CMD.
+ * This command must be executed after every RXON command, before Tx can occur.

  *****************************************************************************/
 
  *****************************************************************************/
 

-/* Tx flags */
+/* REPLY_TX Tx flags field */
+
+/* 1: Use Request-To-Send protocol before this frame.
+ * Mutually exclusive vs. TX_CMD_FLG_CTS_MSK. */

 #define TX_CMD_FLG_RTS_MSK __constant_cpu_to_le32(1 << 1)
 #define TX_CMD_FLG_RTS_MSK __constant_cpu_to_le32(1 << 1)

+
+/* 1: Transmit Clear-To-Send to self before this frame.
+ * Driver should set this for AUTH/DEAUTH/ASSOC-REQ/REASSOC mgmnt frames.
+ * Mutually exclusive vs. TX_CMD_FLG_RTS_MSK. */

 #define TX_CMD_FLG_CTS_MSK __constant_cpu_to_le32(1 << 2)
 #define TX_CMD_FLG_CTS_MSK __constant_cpu_to_le32(1 << 2)

+
+/* 1: Expect ACK from receiving station
+ * 0: Don't expect ACK (MAC header's duration field s/b 0)
+ * Set this for unicast frames, but not broadcast/multicast. */

 #define TX_CMD_FLG_ACK_MSK __constant_cpu_to_le32(1 << 3)
 #define TX_CMD_FLG_ACK_MSK __constant_cpu_to_le32(1 << 3)

+
+/* For 4965:
+ * 1: Use rate scale table (see REPLY_TX_LINK_QUALITY_CMD).
+ *    Tx command's initial_rate_index indicates first rate to try;
+ *    uCode walks through table for additional Tx attempts.
+ * 0: Use Tx rate/MCS from Tx command's rate_n_flags field.
+ *    This rate will be used for all Tx attempts; it will not be scaled. */

 #define TX_CMD_FLG_STA_RATE_MSK __constant_cpu_to_le32(1 << 4)
 #define TX_CMD_FLG_STA_RATE_MSK __constant_cpu_to_le32(1 << 4)

+
+/* 1: Expect immediate block-ack.
+ * Set when Txing a block-ack request frame.  Also set TX_CMD_FLG_ACK_MSK. */

 #define TX_CMD_FLG_IMM_BA_RSP_MASK  __constant_cpu_to_le32(1 << 6)
 #define TX_CMD_FLG_IMM_BA_RSP_MASK  __constant_cpu_to_le32(1 << 6)

+
+/* 1: Frame requires full Tx-Op protection.
+ * Set this if either RTS or CTS Tx Flag gets set. */

 #define TX_CMD_FLG_FULL_TXOP_PROT_MSK __constant_cpu_to_le32(1 << 7)
 #define TX_CMD_FLG_FULL_TXOP_PROT_MSK __constant_cpu_to_le32(1 << 7)

+
+/* Tx antenna selection field; used only for 3945, reserved (0) for 4965.
+ * Set field to "0" to allow 3945 uCode to select antenna (normal usage). */

 #define TX_CMD_FLG_ANT_SEL_MSK __constant_cpu_to_le32(0xf00)
 #define TX_CMD_FLG_ANT_A_MSK __constant_cpu_to_le32(1 << 8)
 #define TX_CMD_FLG_ANT_B_MSK __constant_cpu_to_le32(1 << 9)
 
 #define TX_CMD_FLG_ANT_SEL_MSK __constant_cpu_to_le32(0xf00)
 #define TX_CMD_FLG_ANT_A_MSK __constant_cpu_to_le32(1 << 8)
 #define TX_CMD_FLG_ANT_B_MSK __constant_cpu_to_le32(1 << 9)
 

-/* ucode ignores BT priority for this frame */
+/* 1: Ignore Bluetooth priority for this frame.
+ * 0: Delay Tx until Bluetooth device is done (normal usage). */

 #define TX_CMD_FLG_BT_DIS_MSK __constant_cpu_to_le32(1 << 12)
 
 #define TX_CMD_FLG_BT_DIS_MSK __constant_cpu_to_le32(1 << 12)
 

-/* ucode overrides sequence control */
+/* 1: uCode overrides sequence control field in MAC header.
+ * 0: Driver provides sequence control field in MAC header.
+ * Set this for management frames, non-QOS data frames, non-unicast frames,
+ * and also in Tx command embedded in REPLY_SCAN_CMD for active scans. */

 #define TX_CMD_FLG_SEQ_CTL_MSK __constant_cpu_to_le32(1 << 13)
 
 #define TX_CMD_FLG_SEQ_CTL_MSK __constant_cpu_to_le32(1 << 13)
 

-/* signal that this frame is non-last MPDU */
+/* 1: This frame is non-last MPDU; more fragments are coming.
+ * 0: Last fragment, or not using fragmentation. */

 #define TX_CMD_FLG_MORE_FRAG_MSK __constant_cpu_to_le32(1 << 14)
 
 #define TX_CMD_FLG_MORE_FRAG_MSK __constant_cpu_to_le32(1 << 14)
 

-/* calculate TSF in outgoing frame */
+/* 1: uCode calculates and inserts Timestamp Function (TSF) in outgoing frame.
+ * 0: No TSF required in outgoing frame.
+ * Set this for transmitting beacons and probe responses. */

 #define TX_CMD_FLG_TSF_MSK __constant_cpu_to_le32(1 << 16)
 
 #define TX_CMD_FLG_TSF_MSK __constant_cpu_to_le32(1 << 16)
 

-/* activate TX calibration. */
-#define TX_CMD_FLG_CALIB_MSK __constant_cpu_to_le32(1 << 17)
-
-/* signals that 2 bytes pad was inserted
-   after the MAC header */
+/* 1: Driver inserted 2 bytes pad after the MAC header, for (required) dword
+ *    alignment of frame's payload data field.
+ * 0: No pad
+ * Set this for MAC headers with 26 or 30 bytes, i.e. those with QOS or ADDR4
+ * field (but not both).  Driver must align frame data (i.e. data following
+ * MAC header) to DWORD boundary. */

 #define TX_CMD_FLG_MH_PAD_MSK __constant_cpu_to_le32(1 << 20)
 
 /* HCCA-AP - disable duration overwriting. */
 #define TX_CMD_FLG_DUR_MSK __constant_cpu_to_le32(1 << 25)
 
 #define TX_CMD_FLG_MH_PAD_MSK __constant_cpu_to_le32(1 << 20)
 
 /* HCCA-AP - disable duration overwriting. */
 #define TX_CMD_FLG_DUR_MSK __constant_cpu_to_le32(1 << 25)
 

+

 /*
  * TX command security control
  */
 /*
  * TX command security control
  */


@@ -998,12 +1053,13 @@ struct iwl4965_rx_mpdu_res_start {
 #define TX_CMD_SEC_KEY128      0x08
 
 /*
 #define TX_CMD_SEC_KEY128      0x08
 
 /*

- * TX command Frame life time
+ * 4965 uCode updates these Tx attempt count values in host DRAM.
+ * Used for managing Tx retries when expecting block-acks.
+ * Driver should set these fields to 0.

  */
  */

-

 struct iwl4965_dram_scratch {
 struct iwl4965_dram_scratch {

-       u8 try_cnt;
-       u8 bt_kill_cnt;
+       u8 try_cnt;             /* Tx attempts */
+       u8 bt_kill_cnt;         /* Tx attempts blocked by Bluetooth device */

        __le16 reserved;
 } __attribute__ ((packed));
 
        __le16 reserved;
 } __attribute__ ((packed));
 


@@ -1011,13 +1067,47 @@ struct iwl4965_dram_scratch {
  * REPLY_TX = 0x1c (command)
  */
 struct iwl4965_tx_cmd {
  * REPLY_TX = 0x1c (command)
  */
 struct iwl4965_tx_cmd {

+       /*
+        * MPDU byte count:
+        * MAC header (24/26/30/32 bytes) + 2 bytes pad if 26/30 header size,
+        * + 8 byte IV for CCM or TKIP (not used for WEP)
+        * + Data payload
+        * + 8-byte MIC (not used for CCM/WEP)
+        * NOTE:  Does not include Tx command bytes, post-MAC pad bytes,
+        *        MIC (CCM) 8 bytes, ICV (WEP/TKIP/CKIP) 4 bytes, CRC 4 bytes.i
+        * Range: 14-2342 bytes.
+        */

        __le16 len;
        __le16 len;

+
+       /*
+        * MPDU or MSDU byte count for next frame.
+        * Used for fragmentation and bursting, but not 11n aggregation.
+        * Same as "len", but for next frame.  Set to 0 if not applicable.
+        */

        __le16 next_frame_len;
        __le16 next_frame_len;

-       __le32 tx_flags;
+
+       __le32 tx_flags;        /* TX_CMD_FLG_* */
+
+       /* 4965's uCode may modify this field of the Tx command (in host DRAM!).
+        * Driver must also set dram_lsb_ptr and dram_msb_ptr in this cmd. */

        struct iwl4965_dram_scratch scratch;
        struct iwl4965_dram_scratch scratch;

-       __le32 rate_n_flags;
+
+       /* Rate for *all* Tx attempts, if TX_CMD_FLG_STA_RATE_MSK is cleared. */
+       __le32 rate_n_flags;    /* RATE_MCS_* */
+
+       /* Index of destination station in uCode's station table */

        u8 sta_id;
        u8 sta_id;

-       u8 sec_ctl;
+
+       /* Type of security encryption:  CCM or TKIP */
+       u8 sec_ctl;             /* TX_CMD_SEC_* */
+
+       /*
+        * Index into rate table (see REPLY_TX_LINK_QUALITY_CMD) for initial
+        * Tx attempt, if TX_CMD_FLG_STA_RATE_MSK is set.  Normally "0" for
+        * data frames, this field may be used to selectively reduce initial
+        * rate (via non-0 value) for special frames (e.g. management), while
+        * still supporting rate scaling for all frames.
+        */

        u8 initial_rate_index;
        u8 reserved;
        u8 key[16];
        u8 initial_rate_index;
        u8 reserved;
        u8 key[16];


@@ -1027,8 +1117,12 @@ struct iwl4965_tx_cmd {
                __le32 life_time;
                __le32 attempt;
        } stop_time;
                __le32 life_time;
                __le32 attempt;
        } stop_time;

+
+       /* Host DRAM physical address pointer to "scratch" in this command.
+        * Must be dword aligned.  "0" in dram_lsb_ptr disables usage. */

        __le32 dram_lsb_ptr;
        u8 dram_msb_ptr;
        __le32 dram_lsb_ptr;
        u8 dram_msb_ptr;

+

        u8 rts_retry_limit;     /*byte 50 */
        u8 data_retry_limit;    /*byte 51 */
        u8 tid_tspec;
        u8 rts_retry_limit;     /*byte 50 */
        u8 data_retry_limit;    /*byte 51 */
        u8 tid_tspec;


@@ -1036,7 +1130,17 @@ struct iwl4965_tx_cmd {
                __le16 pm_frame_timeout;
                __le16 attempt_duration;
        } timeout;
                __le16 pm_frame_timeout;
                __le16 attempt_duration;
        } timeout;

+
+       /*
+        * Duration of EDCA burst Tx Opportunity, in 32-usec units.
+        * Set this if txop time is not specified by HCCA protocol (e.g. by AP).
+        */

        __le16 driver_txop;
        __le16 driver_txop;

+
+       /*
+        * MAC header goes here, followed by 2 bytes padding if MAC header
+        * length is 26 or 30 bytes, followed by payload data
+        */

        u8 payload[0];
        struct ieee80211_hdr hdr[0];
 } __attribute__ ((packed));
        u8 payload[0];
        struct ieee80211_hdr hdr[0];
 } __attribute__ ((packed));


@@ -1109,7 +1213,7 @@ enum {
 };
 
 /* *******************************
 };
 
 /* *******************************

- * TX aggregation state
+ * TX aggregation status

  ******************************* */
 
 enum {
  ******************************* */
 
 enum {


@@ -1133,35 +1237,80 @@ enum {
  AGG_TX_STATE_LAST_SENT_TRY_CNT_MSK | \
  AGG_TX_STATE_LAST_SENT_BT_KILL_MSK)
 
  AGG_TX_STATE_LAST_SENT_TRY_CNT_MSK | \
  AGG_TX_STATE_LAST_SENT_BT_KILL_MSK)
 

+/* # tx attempts for first frame in aggregation */

 #define AGG_TX_STATE_TRY_CNT_POS 12
 #define AGG_TX_STATE_TRY_CNT_MSK 0xf000
 
 #define AGG_TX_STATE_TRY_CNT_POS 12
 #define AGG_TX_STATE_TRY_CNT_MSK 0xf000
 

+/* Command ID and sequence number of Tx command for this frame */

 #define AGG_TX_STATE_SEQ_NUM_POS 16
 #define AGG_TX_STATE_SEQ_NUM_MSK 0xffff0000
 
 /*
  * REPLY_TX = 0x1c (response)
 #define AGG_TX_STATE_SEQ_NUM_POS 16
 #define AGG_TX_STATE_SEQ_NUM_MSK 0xffff0000
 
 /*
  * REPLY_TX = 0x1c (response)

+ *
+ * This response may be in one of two slightly different formats, indicated
+ * by the frame_count field:
+ *
+ * 1)  No aggregation (frame_count == 1).  This reports Tx results for
+ *     a single frame.  Multiple attempts, at various bit rates, may have
+ *     been made for this frame.
+ *
+ * 2)  Aggregation (frame_count > 1).  This reports Tx results for
+ *     2 or more frames that used block-acknowledge.  All frames were
+ *     transmitted at same rate.  Rate scaling may have been used if first
+ *     frame in this new agg block failed in previous agg block(s).
+ *
+ *     Note that, for aggregation, ACK (block-ack) status is not delivered here;
+ *     block-ack has not been received by the time the 4965 records this status.
+ *     This status relates to reasons the tx might have been blocked or aborted
+ *     within the sending station (this 4965), rather than whether it was
+ *     received successfully by the destination station.

  */
 struct iwl4965_tx_resp {
        u8 frame_count;         /* 1 no aggregation, >1 aggregation */
  */
 struct iwl4965_tx_resp {
        u8 frame_count;         /* 1 no aggregation, >1 aggregation */

-       u8 bt_kill_count;
-       u8 failure_rts;
-       u8 failure_frame;
-       __le32 rate_n_flags;
-       __le16 wireless_media_time;
+       u8 bt_kill_count;       /* # blocked by bluetooth (unused for agg) */
+       u8 failure_rts;         /* # failures due to unsuccessful RTS */
+       u8 failure_frame;       /* # failures due to no ACK (unused for agg) */
+
+       /* For non-agg:  Rate at which frame was successful.
+        * For agg:  Rate at which all frames were transmitted. */
+       __le32 rate_n_flags;    /* RATE_MCS_*  */
+
+       /* For non-agg:  RTS + CTS + frame tx attempts time + ACK.
+        * For agg:  RTS + CTS + aggregation tx time + block-ack time. */
+       __le16 wireless_media_time;     /* uSecs */
+

        __le16 reserved;
        __le16 reserved;

-       __le32 pa_power1;
+       __le32 pa_power1;       /* RF power amplifier measurement (not used) */

        __le32 pa_power2;
        __le32 pa_power2;

+
+       /*
+        * For non-agg:  frame status TX_STATUS_*
+        * For agg:  status of 1st frame, AGG_TX_STATE_*; other frame status
+        *           fields follow this one, up to frame_count.
+        *           Bit fields:
+        *           11- 0:  AGG_TX_STATE_* status code
+        *           15-12:  Retry count for 1st frame in aggregation (retries
+        *                   occur if tx failed for this frame when it was a
+        *                   member of a previous aggregation block).  If rate
+        *                   scaling is used, retry count indicates the rate
+        *                   table entry used for all frames in the new agg.
+        *           31-16:  Sequence # for this frame's Tx cmd (not SSN!)
+        */

        __le32 status;  /* TX status (for aggregation status of 1st frame) */
 } __attribute__ ((packed));
 
 /*
  * REPLY_COMPRESSED_BA = 0xc5 (response only, not a command)
        __le32 status;  /* TX status (for aggregation status of 1st frame) */
 } __attribute__ ((packed));
 
 /*
  * REPLY_COMPRESSED_BA = 0xc5 (response only, not a command)

+ *
+ * Reports Block-Acknowledge from recipient station

  */
 struct iwl4965_compressed_ba_resp {
        __le32 sta_addr_lo32;
        __le16 sta_addr_hi16;
        __le16 reserved;
  */
 struct iwl4965_compressed_ba_resp {
        __le32 sta_addr_lo32;
        __le16 sta_addr_hi16;
        __le16 reserved;

+
+       /* Index of recipient (BA-sending) station in uCode's station table */

        u8 sta_id;
        u8 tid;
        __le16 ba_seq_ctl;
        u8 sta_id;
        u8 tid;
        __le16 ba_seq_ctl;