iwlwifi: iwl-fh.h cleanup

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / net / wireless / iwlwifi / iwl-fh.h

/******************************************************************************
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
 * USA
 *
 * The full GNU General Public License is included in this distribution
 * in the file called LICENSE.GPL.
 *
 * Contact Information:
 * James P. Ketrenos <ipw2100-admin@linux.intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 * BSD LICENSE
 *
 * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  * Neither the name Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *****************************************************************************/
#ifndef __iwl_fh_h__
#define __iwl_fh_h__

/****************************/
/* Flow Handler Definitions */
/****************************/

/**
 * This I/O area is directly read/writable by driver (e.g. Linux uses writel())
 * Addresses are offsets from device's PCI hardware base address.
 */
#define FH_MEM_LOWER_BOUND                   (0x1000)
#define FH_MEM_UPPER_BOUND                   (0x2000)

/**
 * Keep-Warm (KW) buffer base address.
 *
 * Driver must allocate a 4KByte buffer that is used by 4965 for keeping the
 * host DRAM powered on (via dummy accesses to DRAM) to maintain low-latency
 * DRAM access when 4965 is Txing or Rxing.  The dummy accesses prevent host
 * from going into a power-savings mode that would cause higher DRAM latency,
 * and possible data over/under-runs, before all Tx/Rx is complete.
 *
 * Driver loads FH_KW_MEM_ADDR_REG with the physical address (bits 35:4)
 * of the buffer, which must be 4K aligned.  Once this is set up, the 4965
 * automatically invokes keep-warm accesses when normal accesses might not
 * be sufficient to maintain fast DRAM response.
 *
 * Bit fields:
 *  31-0:  Keep-warm buffer physical base address [35:4], must be 4K aligned
 */
#define FH_KW_MEM_ADDR_REG                   (FH_MEM_LOWER_BOUND + 0x97C)


/**
 * TFD Circular Buffers Base (CBBC) addresses
 *
 * 4965 has 16 base pointer registers, one for each of 16 host-DRAM-resident
 * circular buffers (CBs/queues) containing Transmit Frame Descriptors (TFDs)
 * (see struct iwl_tfd_frame).  These 16 pointer registers are offset by 0x04
 * bytes from one another.  Each TFD circular buffer in DRAM must be 256-byte
 * aligned (address bits 0-7 must be 0).
 *
 * Bit fields in each pointer register:
 *  27-0: TFD CB physical base address [35:8], must be 256-byte aligned
 */
#define FH_MEM_CBBC_LOWER_BOUND          (FH_MEM_LOWER_BOUND + 0x9D0)
#define FH_MEM_CBBC_UPPER_BOUND          (FH_MEM_LOWER_BOUND + 0xA10)

/* Find TFD CB base pointer for given queue (range 0-15). */
#define FH_MEM_CBBC_QUEUE(x)  (FH_MEM_CBBC_LOWER_BOUND + (x) * 0x4)


/**
 * Rx SRAM Control and Status Registers (RSCSR)
 *
 * These registers provide handshake between driver and 4965 for the Rx queue
 * (this queue handles *all* command responses, notifications, Rx data, etc.
 * sent from 4965 uCode to host driver).  Unlike Tx, there is only one Rx
 * queue, and only one Rx DMA/FIFO channel.  Also unlike Tx, which can
 * concatenate up to 20 DRAM buffers to form a Tx frame, each Receive Buffer
 * Descriptor (RBD) points to only one Rx Buffer (RB); there is a 1:1
 * mapping between RBDs and RBs.
 *
 * Driver must allocate host DRAM memory for the following, and set the
 * physical address of each into 4965 registers:
 *
 * 1)  Receive Buffer Descriptor (RBD) circular buffer (CB), typically with 256
 *     entries (although any power of 2, up to 4096, is selectable by driver).
 *     Each entry (1 dword) points to a receive buffer (RB) of consistent size
 *     (typically 4K, although 8K or 16K are also selectable by driver).
 *     Driver sets up RB size and number of RBDs in the CB via Rx config
 *     register FH_MEM_RCSR_CHNL0_CONFIG_REG.
 *
 *     Bit fields within one RBD:
 *     27-0:  Receive Buffer physical address bits [35:8], 256-byte aligned
 *
 *     Driver sets physical address [35:8] of base of RBD circular buffer
 *     into FH_RSCSR_CHNL0_RBDCB_BASE_REG [27:0].
 *
 * 2)  Rx status buffer, 8 bytes, in which 4965 indicates which Rx Buffers
 *     (RBs) have been filled, via a "write pointer", actually the index of
 *     the RB's corresponding RBD within the circular buffer.  Driver sets
 *     physical address [35:4] into FH_RSCSR_CHNL0_STTS_WPTR_REG [31:0].
 *
 *     Bit fields in lower dword of Rx status buffer (upper dword not used
 *     by driver; see struct iwl4965_shared, val0):
 *     31-12:  Not used by driver
 *     11- 0:  Index of last filled Rx buffer descriptor
 *             (4965 writes, driver reads this value)
 *
 * As the driver prepares Receive Buffers (RBs) for 4965 to fill, driver must
 * enter pointers to these RBs into contiguous RBD circular buffer entries,
 * and update the 4965's "write" index register,
 * FH_RSCSR_CHNL0_RBDCB_WPTR_REG.
 *
 * This "write" index corresponds to the *next* RBD that the driver will make
 * available, i.e. one RBD past the tail of the ready-to-fill RBDs within
 * the circular buffer.  This value should initially be 0 (before preparing any
 * RBs), should be 8 after preparing the first 8 RBs (for example), and must
 * wrap back to 0 at the end of the circular buffer (but don't wrap before
 * "read" index has advanced past 1!  See below).
 * NOTE:  4965 EXPECTS THE WRITE INDEX TO BE INCREMENTED IN MULTIPLES OF 8.
 *
 * As the 4965 fills RBs (referenced from contiguous RBDs within the circular
 * buffer), it updates the Rx status buffer in host DRAM, 2) described above,
 * to tell the driver the index of the latest filled RBD.  The driver must
 * read this "read" index from DRAM after receiving an Rx interrupt from 4965.
 *
 * The driver must also internally keep track of a third index, which is the
 * next RBD to process.  When receiving an Rx interrupt, driver should process
 * all filled but unprocessed RBs up to, but not including, the RB
 * corresponding to the "read" index.  For example, if "read" index becomes "1",
 * driver may process the RB pointed to by RBD 0.  Depending on volume of
 * traffic, there may be many RBs to process.
 *
 * If read index == write index, 4965 thinks there is no room to put new data.
 * Due to this, the maximum number of filled RBs is 255, instead of 256.  To
 * be safe, make sure that there is a gap of at least 2 RBDs between "write"
 * and "read" indexes; that is, make sure that there are no more than 254
 * buffers waiting to be filled.
 */
#define FH_MEM_RSCSR_LOWER_BOUND        (FH_MEM_LOWER_BOUND + 0xBC0)
#define FH_MEM_RSCSR_UPPER_BOUND        (FH_MEM_LOWER_BOUND + 0xC00)
#define FH_MEM_RSCSR_CHNL0              (FH_MEM_RSCSR_LOWER_BOUND)

/**
 * Physical base address of 8-byte Rx Status buffer.
 * Bit fields:
 *  31-0: Rx status buffer physical base address [35:4], must 16-byte aligned.
 */
#define FH_RSCSR_CHNL0_STTS_WPTR_REG    (FH_MEM_RSCSR_CHNL0)

/**
 * Physical base address of Rx Buffer Descriptor Circular Buffer.
 * Bit fields:
 *  27-0:  RBD CD physical base address [35:8], must be 256-byte aligned.
 */
#define FH_RSCSR_CHNL0_RBDCB_BASE_REG   (FH_MEM_RSCSR_CHNL0 + 0x004)

/**
 * Rx write pointer (index, really!).
 * Bit fields:
 *  11-0:  Index of driver's most recent prepared-to-be-filled RBD, + 1.
 *         NOTE:  For 256-entry circular buffer, use only bits [7:0].
 */
#define FH_RSCSR_CHNL0_RBDCB_WPTR_REG   (FH_MEM_RSCSR_CHNL0 + 0x008)
#define FH_RSCSR_CHNL0_WPTR        (FH_RSCSR_CHNL0_RBDCB_WPTR_REG)


/**
 * Rx Config/Status Registers (RCSR)
 * Rx Config Reg for channel 0 (only channel used)
 *
 * Driver must initialize FH_MEM_RCSR_CHNL0_CONFIG_REG as follows for
 * normal operation (see bit fields).
 *
 * Clearing FH_MEM_RCSR_CHNL0_CONFIG_REG to 0 turns off Rx DMA.
 * Driver should poll FH_MEM_RSSR_RX_STATUS_REG for
 * FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE (bit 24) before continuing.
 *
 * Bit fields:
 * 31-30: Rx DMA channel enable: '00' off/pause, '01' pause at end of frame,
 *        '10' operate normally
 * 29-24: reserved
 * 23-20: # RBDs in circular buffer = 2^value; use "8" for 256 RBDs (normal),
 *        min "5" for 32 RBDs, max "12" for 4096 RBDs.
 * 19-18: reserved
 * 17-16: size of each receive buffer; '00' 4K (normal), '01' 8K,
 *        '10' 12K, '11' 16K.
 * 15-14: reserved
 * 13-12: IRQ destination; '00' none, '01' host driver (normal operation)
 * 11- 4: timeout for closing Rx buffer and interrupting host (units 32 usec)
 *        typical value 0x10 (about 1/2 msec)
 *  3- 0: reserved
 */
#define FH_MEM_RCSR_LOWER_BOUND      (FH_MEM_LOWER_BOUND + 0xC00)
#define FH_MEM_RCSR_UPPER_BOUND      (FH_MEM_LOWER_BOUND + 0xCC0)
#define FH_MEM_RCSR_CHNL0            (FH_MEM_RCSR_LOWER_BOUND)

#define FH_MEM_RCSR_CHNL0_CONFIG_REG    (FH_MEM_RCSR_CHNL0)

#define FH_RCSR_CHNL0_RX_CONFIG_RB_TIMEOUT_MSK (0x00000FF0) /* bits 4-11 */
#define FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_MSK   (0x00001000) /* bits 12 */
#define FH_RCSR_CHNL0_RX_CONFIG_SINGLE_FRAME_MSK (0x00008000) /* bit 15 */
#define FH_RCSR_CHNL0_RX_CONFIG_RB_SIZE_MSK   (0x00030000) /* bits 16-17 */
#define FH_RCSR_CHNL0_RX_CONFIG_RBDBC_SIZE_MSK (0x00F00000) /* bits 20-23 */
#define FH_RCSR_CHNL0_RX_CONFIG_DMA_CHNL_EN_MSK (0xC0000000) /* bits 30-31*/

#define FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS        (20)
#define FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS      (4)
#define RX_RB_TIMEOUT   (0x10)

#define FH_RCSR_RX_CONFIG_CHNL_EN_PAUSE_VAL         (0x00000000)
#define FH_RCSR_RX_CONFIG_CHNL_EN_PAUSE_EOF_VAL     (0x40000000)
#define FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL        (0x80000000)

#define FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K    (0x00000000)
#define FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K    (0x00010000)
#define FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_12K   (0x00020000)
#define FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_16K   (0x00030000)

#define FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY              (0x00000004)
#define FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_NO_INT_VAL    (0x00000000)
#define FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL  (0x00001000)

#define FH_RCSR_CHNL0_RX_CONFIG_SINGLE_FRAME    (0x00008000)

#define FH_RSCSR_FRAME_SIZE_MSK (0x00003FFF)    /* bits 0-13 */


/**
 * Rx Shared Status Registers (RSSR)
 *
 * After stopping Rx DMA channel (writing 0 to
 * FH_MEM_RCSR_CHNL0_CONFIG_REG), driver must poll
 * FH_MEM_RSSR_RX_STATUS_REG until Rx channel is idle.
 *
 * Bit fields:
 *  24:  1 = Channel 0 is idle
 *
 * FH_MEM_RSSR_SHARED_CTRL_REG and FH_MEM_RSSR_RX_ENABLE_ERR_IRQ2DRV
 * contain default values that should not be altered by the driver.
 */
#define FH_MEM_RSSR_LOWER_BOUND           (FH_MEM_LOWER_BOUND + 0xC40)
#define FH_MEM_RSSR_UPPER_BOUND           (FH_MEM_LOWER_BOUND + 0xD00)

#define FH_MEM_RSSR_SHARED_CTRL_REG       (FH_MEM_RSSR_LOWER_BOUND)
#define FH_MEM_RSSR_RX_STATUS_REG       (FH_MEM_RSSR_LOWER_BOUND + 0x004)
#define FH_MEM_RSSR_RX_ENABLE_ERR_IRQ2DRV\
                                        (FH_MEM_RSSR_LOWER_BOUND + 0x008)

#define FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE       (0x01000000)

#define FH_MEM_TFDIB_REG1_ADDR_BITSHIFT 28

/* TFDB  Area - TFDs buffer table */
#define FH_MEM_TFDIB_DRAM_ADDR_LSB_MSK      (0xFFFFFFFF)
#define FH_TFDIB_LOWER_BOUND       (FH_MEM_LOWER_BOUND + 0x900)
#define FH_TFDIB_UPPER_BOUND       (FH_MEM_LOWER_BOUND + 0x958)
#define FH_TFDIB_CTRL0_REG(_chnl)  (FH_TFDIB_LOWER_BOUND + 0x8 * (_chnl))
#define FH_TFDIB_CTRL1_REG(_chnl)  (FH_TFDIB_LOWER_BOUND + 0x8 * (_chnl) + 0x4)

/**
 * Transmit DMA Channel Control/Status Registers (TCSR)
 *
 * 4965 has one configuration register for each of 8 Tx DMA/FIFO channels
 * supported in hardware (don't confuse these with the 16 Tx queues in DRAM,
 * which feed the DMA/FIFO channels); config regs are separated by 0x20 bytes.
 *
 * To use a Tx DMA channel, driver must initialize its
 * FH_TCSR_CHNL_TX_CONFIG_REG(chnl) with:
 *
 * FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_ENABLE |
 * FH_TCSR_TX_CONFIG_REG_VAL_DMA_CREDIT_ENABLE_VAL
 *
 * All other bits should be 0.
 *
 * Bit fields:
 * 31-30: Tx DMA channel enable: '00' off/pause, '01' pause at end of frame,
 *        '10' operate normally
 * 29- 4: Reserved, set to "0"
 *     3: Enable internal DMA requests (1, normal operation), disable (0)
 *  2- 0: Reserved, set to "0"
 */
#define FH_TCSR_LOWER_BOUND  (FH_MEM_LOWER_BOUND + 0xD00)
#define FH_TCSR_UPPER_BOUND  (FH_MEM_LOWER_BOUND + 0xE60)

/* Find Control/Status reg for given Tx DMA/FIFO channel */
#define FH49_TCSR_CHNL_NUM                            (7)
#define FH50_TCSR_CHNL_NUM                            (8)

/* TCSR: tx_config register values */
#define FH_TCSR_CHNL_TX_CONFIG_REG(_chnl)       \
                (FH_TCSR_LOWER_BOUND + 0x20 * (_chnl))
#define FH_TCSR_CHNL_TX_CREDIT_REG(_chnl)       \
                (FH_TCSR_LOWER_BOUND + 0x20 * (_chnl) + 0x4)
#define FH_TCSR_CHNL_TX_BUF_STS_REG(_chnl)      \
                (FH_TCSR_LOWER_BOUND + 0x20 * (_chnl) + 0x8)

#define FH_TCSR_TX_CONFIG_REG_VAL_MSG_MODE_TXF          (0x00000000)
#define FH_TCSR_TX_CONFIG_REG_VAL_MSG_MODE_DRV          (0x00000001)

#define FH_TCSR_TX_CONFIG_REG_VAL_DMA_CREDIT_DISABLE    (0x00000000)
#define FH_TCSR_TX_CONFIG_REG_VAL_DMA_CREDIT_ENABLE     (0x00000008)

#define FH_TCSR_TX_CONFIG_REG_VAL_CIRQ_HOST_NOINT       (0x00000000)
#define FH_TCSR_TX_CONFIG_REG_VAL_CIRQ_HOST_ENDTFD      (0x00100000)
#define FH_TCSR_TX_CONFIG_REG_VAL_CIRQ_HOST_IFTFD       (0x00200000)

#define FH_TCSR_TX_CONFIG_REG_VAL_CIRQ_RTC_NOINT        (0x00000000)
#define FH_TCSR_TX_CONFIG_REG_VAL_CIRQ_RTC_ENDTFD       (0x00400000)
#define FH_TCSR_TX_CONFIG_REG_VAL_CIRQ_RTC_IFTFD        (0x00800000)

#define FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_PAUSE        (0x00000000)
#define FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_PAUSE_EOF    (0x40000000)
#define FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_ENABLE       (0x80000000)

#define FH_TCSR_CHNL_TX_BUF_STS_REG_VAL_TFDB_EMPTY      (0x00000000)
#define FH_TCSR_CHNL_TX_BUF_STS_REG_VAL_TFDB_WAIT       (0x00002000)
#define FH_TCSR_CHNL_TX_BUF_STS_REG_VAL_TFDB_VALID      (0x00000003)

#define FH_TCSR_CHNL_TX_BUF_STS_REG_POS_TB_NUM          (20)
#define FH_TCSR_CHNL_TX_BUF_STS_REG_POS_TB_IDX          (12)

/**
 * Tx Shared Status Registers (TSSR)
 *
 * After stopping Tx DMA channel (writing 0 to
 * FH_TCSR_CHNL_TX_CONFIG_REG(chnl)), driver must poll
 * FH_TSSR_TX_STATUS_REG until selected Tx channel is idle
 * (channel's buffers empty | no pending requests).
 *
 * Bit fields:
 * 31-24:  1 = Channel buffers empty (channel 7:0)
 * 23-16:  1 = No pending requests (channel 7:0)
 */
#define FH_TSSR_LOWER_BOUND             (FH_MEM_LOWER_BOUND + 0xEA0)
#define FH_TSSR_UPPER_BOUND             (FH_MEM_LOWER_BOUND + 0xEC0)

#define FH_TSSR_TX_STATUS_REG           (FH_TSSR_LOWER_BOUND + 0x010)

#define FH_TSSR_TX_STATUS_REG_BIT_BUFS_EMPTY(_chnl) ((1 << (_chnl)) << 24)
#define FH_TSSR_TX_STATUS_REG_BIT_NO_PEND_REQ(_chnl) ((1 << (_chnl)) << 16)

#define FH_TSSR_TX_STATUS_REG_MSK_CHNL_IDLE(_chnl) \
        (FH_TSSR_TX_STATUS_REG_BIT_BUFS_EMPTY(_chnl) | \
        FH_TSSR_TX_STATUS_REG_BIT_NO_PEND_REQ(_chnl))

/* Tx service channels */
#define FH_SRVC_CHNL            (9)
#define FH_SRVC_LOWER_BOUND     (FH_MEM_LOWER_BOUND + 0x9C8)
#define FH_SRVC_UPPER_BOUND     (FH_MEM_LOWER_BOUND + 0x9D0)
#define FH_SRVC_CHNL_SRAM_ADDR_REG(_chnl) \
                (FH_SRVC_LOWER_BOUND + ((_chnl) - 9) * 0x4)


/**
 * struct iwl_rb_status - reseve buffer status
 *      host memory mapped FH registers
 * @closed_rb_num [0:11] - Indicates the index of the RB which was closed
 * @closed_fr_num [0:11] - Indicates the index of the RX Frame which was closed
 * @finished_rb_num [0:11] - Indicates the index of the current RB
 *      in which the last frame was written to
 * @finished_fr_num [0:11] - Indicates the index of the RX Frame
 *      which was transfered
 */
struct iwl_rb_status {
        __le16 closed_rb_num;
        __le16 closed_fr_num;
        __le16 finished_rb_num;
        __le16 finished_fr_nam;
} __attribute__ ((packed));


#define TFD_QUEUE_SIZE_MAX      (256)
#define TFD_QUEUE_SIZE_BC_DUP   (64)
#define TFD_QUEUE_BC_SIZE       (TFD_QUEUE_SIZE_MAX + TFD_QUEUE_SIZE_BC_DUP)
#define IWL_TX_DMA_MASK        DMA_BIT_MASK(36)
#define IWL_NUM_OF_TBS          20

static inline u8 iwl_get_dma_hi_addr(dma_addr_t addr)
{
        return (sizeof(addr) > sizeof(u32) ? (addr >> 16) >> 16 : 0) & 0xF;
}
/**
 * struct iwl_tfd_tb transmit buffer descriptor within transmit frame descriptor
 *
 * This structure contains dma address and length of transmission address
 *
 * @lo: low [31:0] portion of the dma address of TX buffer
 *      every even is unaligned on 16 bit boundary
 * @hi_n_len 0-3 [35:32] portion of dma
 *           4-15 length of the tx buffer
 */
struct iwl_tfd_tb {
        __le32 lo;
        __le16 hi_n_len;
} __attribute__((packed));

/**
 * struct iwl_tfd
 *
 * Transmit Frame Descriptor (TFD)
 *
 * @ __reserved1[3] reserved
 * @ num_tbs 0-4 number of active tbs
 *           5   reserved
 *           6-7 padding (not used)
 * @ tbs[20]    transmit frame buffer descriptors
 * @ __pad      padding
 *
 * Each Tx queue uses a circular buffer of 256 TFDs stored in host DRAM.
 * Both driver and device share these circular buffers, each of which must be
 * contiguous 256 TFDs x 128 bytes-per-TFD = 32 KBytes
 *
 * Driver must indicate the physical address of the base of each
 * circular buffer via the FH_MEM_CBBC_QUEUE registers.
 *
 * Each TFD contains pointer/size information for up to 20 data buffers
 * in host DRAM.  These buffers collectively contain the (one) frame described
 * by the TFD.  Each buffer must be a single contiguous block of memory within
 * itself, but buffers may be scattered in host DRAM.  Each buffer has max size
 * of (4K - 4).  The concatenates all of a TFD's buffers into a single
 * Tx frame, up to 8 KBytes in size.
 *
 * A maximum of 255 (not 256!) TFDs may be on a queue waiting for Tx.
 */
struct iwl_tfd {
        u8 __reserved1[3];
        u8 num_tbs;
        struct iwl_tfd_tb tbs[IWL_NUM_OF_TBS];
        __le32 __pad;
} __attribute__ ((packed));


/* Keep Warm Size */
#define IWL_KW_SIZE 0x1000      /* 4k */

#endif /* !__iwl_fh_h__ */