root/sys/dev/iavf/iavf_adminq.c
/* SPDX-License-Identifier: BSD-3-Clause */
/*  Copyright (c) 2021, Intel Corporation
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *   2. 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.
 *
 *   3. Neither the name of the 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.
 */

#include "iavf_status.h"
#include "iavf_type.h"
#include "iavf_register.h"
#include "iavf_adminq.h"
#include "iavf_prototype.h"

/**
 *  iavf_adminq_init_regs - Initialize AdminQ registers
 *  @hw: pointer to the hardware structure
 *
 *  This assumes the alloc_asq and alloc_arq functions have already been called
 **/
STATIC void iavf_adminq_init_regs(struct iavf_hw *hw)
{
        /* set head and tail registers in our local struct */
        hw->aq.asq.tail = IAVF_VF_ATQT1;
        hw->aq.asq.head = IAVF_VF_ATQH1;
        hw->aq.asq.len  = IAVF_VF_ATQLEN1;
        hw->aq.asq.bal  = IAVF_VF_ATQBAL1;
        hw->aq.asq.bah  = IAVF_VF_ATQBAH1;
        hw->aq.arq.tail = IAVF_VF_ARQT1;
        hw->aq.arq.head = IAVF_VF_ARQH1;
        hw->aq.arq.len  = IAVF_VF_ARQLEN1;
        hw->aq.arq.bal  = IAVF_VF_ARQBAL1;
        hw->aq.arq.bah  = IAVF_VF_ARQBAH1;
}

/**
 *  iavf_alloc_adminq_asq_ring - Allocate Admin Queue send rings
 *  @hw: pointer to the hardware structure
 **/
enum iavf_status iavf_alloc_adminq_asq_ring(struct iavf_hw *hw)
{
        enum iavf_status ret_code;

        ret_code = iavf_allocate_dma_mem(hw, &hw->aq.asq.desc_buf,
                                         iavf_mem_atq_ring,
                                         (hw->aq.num_asq_entries *
                                         sizeof(struct iavf_aq_desc)),
                                         IAVF_ADMINQ_DESC_ALIGNMENT);
        if (ret_code)
                return ret_code;

        ret_code = iavf_allocate_virt_mem(hw, &hw->aq.asq.cmd_buf,
                                          (hw->aq.num_asq_entries *
                                          sizeof(struct iavf_asq_cmd_details)));
        if (ret_code) {
                iavf_free_dma_mem(hw, &hw->aq.asq.desc_buf);
                return ret_code;
        }

        return ret_code;
}

/**
 *  iavf_alloc_adminq_arq_ring - Allocate Admin Queue receive rings
 *  @hw: pointer to the hardware structure
 **/
enum iavf_status iavf_alloc_adminq_arq_ring(struct iavf_hw *hw)
{
        enum iavf_status ret_code;

        ret_code = iavf_allocate_dma_mem(hw, &hw->aq.arq.desc_buf,
                                         iavf_mem_arq_ring,
                                         (hw->aq.num_arq_entries *
                                         sizeof(struct iavf_aq_desc)),
                                         IAVF_ADMINQ_DESC_ALIGNMENT);

        return ret_code;
}

/**
 *  iavf_free_adminq_asq - Free Admin Queue send rings
 *  @hw: pointer to the hardware structure
 *
 *  This assumes the posted send buffers have already been cleaned
 *  and de-allocated
 **/
void iavf_free_adminq_asq(struct iavf_hw *hw)
{
        iavf_free_virt_mem(hw, &hw->aq.asq.cmd_buf);
        iavf_free_dma_mem(hw, &hw->aq.asq.desc_buf);
}

/**
 *  iavf_free_adminq_arq - Free Admin Queue receive rings
 *  @hw: pointer to the hardware structure
 *
 *  This assumes the posted receive buffers have already been cleaned
 *  and de-allocated
 **/
void iavf_free_adminq_arq(struct iavf_hw *hw)
{
        iavf_free_dma_mem(hw, &hw->aq.arq.desc_buf);
}

/**
 *  iavf_alloc_arq_bufs - Allocate pre-posted buffers for the receive queue
 *  @hw: pointer to the hardware structure
 **/
STATIC enum iavf_status iavf_alloc_arq_bufs(struct iavf_hw *hw)
{
        enum iavf_status ret_code;
        struct iavf_aq_desc *desc;
        struct iavf_dma_mem *bi;
        int i;

        /* We'll be allocating the buffer info memory first, then we can
         * allocate the mapped buffers for the event processing
         */

        /* buffer_info structures do not need alignment */
        ret_code = iavf_allocate_virt_mem(hw, &hw->aq.arq.dma_head,
                (hw->aq.num_arq_entries * sizeof(struct iavf_dma_mem)));
        if (ret_code)
                goto alloc_arq_bufs;
        hw->aq.arq.r.arq_bi = (struct iavf_dma_mem *)hw->aq.arq.dma_head.va;

        /* allocate the mapped buffers */
        for (i = 0; i < hw->aq.num_arq_entries; i++) {
                bi = &hw->aq.arq.r.arq_bi[i];
                ret_code = iavf_allocate_dma_mem(hw, bi,
                                                 iavf_mem_arq_buf,
                                                 hw->aq.arq_buf_size,
                                                 IAVF_ADMINQ_DESC_ALIGNMENT);
                if (ret_code)
                        goto unwind_alloc_arq_bufs;

                /* now configure the descriptors for use */
                desc = IAVF_ADMINQ_DESC(hw->aq.arq, i);

                desc->flags = CPU_TO_LE16(IAVF_AQ_FLAG_BUF);
                if (hw->aq.arq_buf_size > IAVF_AQ_LARGE_BUF)
                        desc->flags |= CPU_TO_LE16(IAVF_AQ_FLAG_LB);
                desc->opcode = 0;
                /* This is in accordance with Admin queue design, there is no
                 * register for buffer size configuration
                 */
                desc->datalen = CPU_TO_LE16((u16)bi->size);
                desc->retval = 0;
                desc->cookie_high = 0;
                desc->cookie_low = 0;
                desc->params.external.addr_high =
                        CPU_TO_LE32(IAVF_HI_DWORD(bi->pa));
                desc->params.external.addr_low =
                        CPU_TO_LE32(IAVF_LO_DWORD(bi->pa));
                desc->params.external.param0 = 0;
                desc->params.external.param1 = 0;
        }

alloc_arq_bufs:
        return ret_code;

unwind_alloc_arq_bufs:
        /* don't try to free the one that failed... */
        i--;
        for (; i >= 0; i--)
                iavf_free_dma_mem(hw, &hw->aq.arq.r.arq_bi[i]);
        iavf_free_virt_mem(hw, &hw->aq.arq.dma_head);

        return ret_code;
}

/**
 *  iavf_alloc_asq_bufs - Allocate empty buffer structs for the send queue
 *  @hw: pointer to the hardware structure
 **/
STATIC enum iavf_status iavf_alloc_asq_bufs(struct iavf_hw *hw)
{
        enum iavf_status ret_code;
        struct iavf_dma_mem *bi;
        int i;

        /* No mapped memory needed yet, just the buffer info structures */
        ret_code = iavf_allocate_virt_mem(hw, &hw->aq.asq.dma_head,
                (hw->aq.num_asq_entries * sizeof(struct iavf_dma_mem)));
        if (ret_code)
                goto alloc_asq_bufs;
        hw->aq.asq.r.asq_bi = (struct iavf_dma_mem *)hw->aq.asq.dma_head.va;

        /* allocate the mapped buffers */
        for (i = 0; i < hw->aq.num_asq_entries; i++) {
                bi = &hw->aq.asq.r.asq_bi[i];
                ret_code = iavf_allocate_dma_mem(hw, bi,
                                                 iavf_mem_asq_buf,
                                                 hw->aq.asq_buf_size,
                                                 IAVF_ADMINQ_DESC_ALIGNMENT);
                if (ret_code)
                        goto unwind_alloc_asq_bufs;
        }
alloc_asq_bufs:
        return ret_code;

unwind_alloc_asq_bufs:
        /* don't try to free the one that failed... */
        i--;
        for (; i >= 0; i--)
                iavf_free_dma_mem(hw, &hw->aq.asq.r.asq_bi[i]);
        iavf_free_virt_mem(hw, &hw->aq.asq.dma_head);

        return ret_code;
}

/**
 *  iavf_free_arq_bufs - Free receive queue buffer info elements
 *  @hw: pointer to the hardware structure
 **/
STATIC void iavf_free_arq_bufs(struct iavf_hw *hw)
{
        int i;

        /* free descriptors */
        for (i = 0; i < hw->aq.num_arq_entries; i++)
                iavf_free_dma_mem(hw, &hw->aq.arq.r.arq_bi[i]);

        /* free the descriptor memory */
        iavf_free_dma_mem(hw, &hw->aq.arq.desc_buf);

        /* free the dma header */
        iavf_free_virt_mem(hw, &hw->aq.arq.dma_head);
}

/**
 *  iavf_free_asq_bufs - Free send queue buffer info elements
 *  @hw: pointer to the hardware structure
 **/
STATIC void iavf_free_asq_bufs(struct iavf_hw *hw)
{
        int i;

        /* only unmap if the address is non-NULL */
        for (i = 0; i < hw->aq.num_asq_entries; i++)
                if (hw->aq.asq.r.asq_bi[i].pa)
                        iavf_free_dma_mem(hw, &hw->aq.asq.r.asq_bi[i]);

        /* free the buffer info list */
        iavf_free_virt_mem(hw, &hw->aq.asq.cmd_buf);

        /* free the descriptor memory */
        iavf_free_dma_mem(hw, &hw->aq.asq.desc_buf);

        /* free the dma header */
        iavf_free_virt_mem(hw, &hw->aq.asq.dma_head);
}

/**
 *  iavf_config_asq_regs - configure ASQ registers
 *  @hw: pointer to the hardware structure
 *
 *  Configure base address and length registers for the transmit queue
 **/
STATIC enum iavf_status iavf_config_asq_regs(struct iavf_hw *hw)
{
        enum iavf_status ret_code = IAVF_SUCCESS;
        u32 reg = 0;

        /* Clear Head and Tail */
        wr32(hw, hw->aq.asq.head, 0);
        wr32(hw, hw->aq.asq.tail, 0);

        /* set starting point */
        wr32(hw, hw->aq.asq.len, (hw->aq.num_asq_entries |
                                  IAVF_VF_ATQLEN1_ATQENABLE_MASK));
        wr32(hw, hw->aq.asq.bal, IAVF_LO_DWORD(hw->aq.asq.desc_buf.pa));
        wr32(hw, hw->aq.asq.bah, IAVF_HI_DWORD(hw->aq.asq.desc_buf.pa));

        /* Check one register to verify that config was applied */
        reg = rd32(hw, hw->aq.asq.bal);
        if (reg != IAVF_LO_DWORD(hw->aq.asq.desc_buf.pa))
                ret_code = IAVF_ERR_ADMIN_QUEUE_ERROR;

        return ret_code;
}

/**
 *  iavf_config_arq_regs - ARQ register configuration
 *  @hw: pointer to the hardware structure
 *
 * Configure base address and length registers for the receive (event queue)
 **/
STATIC enum iavf_status iavf_config_arq_regs(struct iavf_hw *hw)
{
        enum iavf_status ret_code = IAVF_SUCCESS;
        u32 reg = 0;

        /* Clear Head and Tail */
        wr32(hw, hw->aq.arq.head, 0);
        wr32(hw, hw->aq.arq.tail, 0);

        /* set starting point */
        wr32(hw, hw->aq.arq.len, (hw->aq.num_arq_entries |
                                  IAVF_VF_ARQLEN1_ARQENABLE_MASK));
        wr32(hw, hw->aq.arq.bal, IAVF_LO_DWORD(hw->aq.arq.desc_buf.pa));
        wr32(hw, hw->aq.arq.bah, IAVF_HI_DWORD(hw->aq.arq.desc_buf.pa));

        /* Update tail in the HW to post pre-allocated buffers */
        wr32(hw, hw->aq.arq.tail, hw->aq.num_arq_entries - 1);

        /* Check one register to verify that config was applied */
        reg = rd32(hw, hw->aq.arq.bal);
        if (reg != IAVF_LO_DWORD(hw->aq.arq.desc_buf.pa))
                ret_code = IAVF_ERR_ADMIN_QUEUE_ERROR;

        return ret_code;
}

/**
 *  iavf_init_asq - main initialization routine for ASQ
 *  @hw: pointer to the hardware structure
 *
 *  This is the main initialization routine for the Admin Send Queue
 *  Prior to calling this function, drivers *MUST* set the following fields
 *  in the hw->aq structure:
 *     - hw->aq.num_asq_entries
 *     - hw->aq.arq_buf_size
 *
 *  Do *NOT* hold the lock when calling this as the memory allocation routines
 *  called are not going to be atomic context safe
 **/
enum iavf_status iavf_init_asq(struct iavf_hw *hw)
{
        enum iavf_status ret_code = IAVF_SUCCESS;

        if (hw->aq.asq.count > 0) {
                /* queue already initialized */
                ret_code = IAVF_ERR_NOT_READY;
                goto init_adminq_exit;
        }

        /* verify input for valid configuration */
        if ((hw->aq.num_asq_entries == 0) ||
            (hw->aq.asq_buf_size == 0)) {
                ret_code = IAVF_ERR_CONFIG;
                goto init_adminq_exit;
        }

        hw->aq.asq.next_to_use = 0;
        hw->aq.asq.next_to_clean = 0;

        /* allocate the ring memory */
        ret_code = iavf_alloc_adminq_asq_ring(hw);
        if (ret_code != IAVF_SUCCESS)
                goto init_adminq_exit;

        /* allocate buffers in the rings */
        ret_code = iavf_alloc_asq_bufs(hw);
        if (ret_code != IAVF_SUCCESS)
                goto init_adminq_free_rings;

        /* initialize base registers */
        ret_code = iavf_config_asq_regs(hw);
        if (ret_code != IAVF_SUCCESS)
                goto init_config_regs;

        /* success! */
        hw->aq.asq.count = hw->aq.num_asq_entries;
        goto init_adminq_exit;

init_adminq_free_rings:
        iavf_free_adminq_asq(hw);
        return ret_code;

init_config_regs:
        iavf_free_asq_bufs(hw);

init_adminq_exit:
        return ret_code;
}

/**
 *  iavf_init_arq - initialize ARQ
 *  @hw: pointer to the hardware structure
 *
 *  The main initialization routine for the Admin Receive (Event) Queue.
 *  Prior to calling this function, drivers *MUST* set the following fields
 *  in the hw->aq structure:
 *     - hw->aq.num_asq_entries
 *     - hw->aq.arq_buf_size
 *
 *  Do *NOT* hold the lock when calling this as the memory allocation routines
 *  called are not going to be atomic context safe
 **/
enum iavf_status iavf_init_arq(struct iavf_hw *hw)
{
        enum iavf_status ret_code = IAVF_SUCCESS;

        if (hw->aq.arq.count > 0) {
                /* queue already initialized */
                ret_code = IAVF_ERR_NOT_READY;
                goto init_adminq_exit;
        }

        /* verify input for valid configuration */
        if ((hw->aq.num_arq_entries == 0) ||
            (hw->aq.arq_buf_size == 0)) {
                ret_code = IAVF_ERR_CONFIG;
                goto init_adminq_exit;
        }

        hw->aq.arq.next_to_use = 0;
        hw->aq.arq.next_to_clean = 0;

        /* allocate the ring memory */
        ret_code = iavf_alloc_adminq_arq_ring(hw);
        if (ret_code != IAVF_SUCCESS)
                goto init_adminq_exit;

        /* allocate buffers in the rings */
        ret_code = iavf_alloc_arq_bufs(hw);
        if (ret_code != IAVF_SUCCESS)
                goto init_adminq_free_rings;

        /* initialize base registers */
        ret_code = iavf_config_arq_regs(hw);
        if (ret_code != IAVF_SUCCESS)
                goto init_adminq_free_rings;

        /* success! */
        hw->aq.arq.count = hw->aq.num_arq_entries;
        goto init_adminq_exit;

init_adminq_free_rings:
        iavf_free_adminq_arq(hw);

init_adminq_exit:
        return ret_code;
}

/**
 *  iavf_shutdown_asq - shutdown the ASQ
 *  @hw: pointer to the hardware structure
 *
 *  The main shutdown routine for the Admin Send Queue
 **/
enum iavf_status iavf_shutdown_asq(struct iavf_hw *hw)
{
        enum iavf_status ret_code = IAVF_SUCCESS;

        iavf_acquire_spinlock(&hw->aq.asq_spinlock);

        if (hw->aq.asq.count == 0) {
                ret_code = IAVF_ERR_NOT_READY;
                goto shutdown_asq_out;
        }

        /* Stop firmware AdminQ processing */
        wr32(hw, hw->aq.asq.head, 0);
        wr32(hw, hw->aq.asq.tail, 0);
        wr32(hw, hw->aq.asq.len, 0);
        wr32(hw, hw->aq.asq.bal, 0);
        wr32(hw, hw->aq.asq.bah, 0);

        hw->aq.asq.count = 0; /* to indicate uninitialized queue */

        /* free ring buffers */
        iavf_free_asq_bufs(hw);

shutdown_asq_out:
        iavf_release_spinlock(&hw->aq.asq_spinlock);
        return ret_code;
}

/**
 *  iavf_shutdown_arq - shutdown ARQ
 *  @hw: pointer to the hardware structure
 *
 *  The main shutdown routine for the Admin Receive Queue
 **/
enum iavf_status iavf_shutdown_arq(struct iavf_hw *hw)
{
        enum iavf_status ret_code = IAVF_SUCCESS;

        iavf_acquire_spinlock(&hw->aq.arq_spinlock);

        if (hw->aq.arq.count == 0) {
                ret_code = IAVF_ERR_NOT_READY;
                goto shutdown_arq_out;
        }

        /* Stop firmware AdminQ processing */
        wr32(hw, hw->aq.arq.head, 0);
        wr32(hw, hw->aq.arq.tail, 0);
        wr32(hw, hw->aq.arq.len, 0);
        wr32(hw, hw->aq.arq.bal, 0);
        wr32(hw, hw->aq.arq.bah, 0);

        hw->aq.arq.count = 0; /* to indicate uninitialized queue */

        /* free ring buffers */
        iavf_free_arq_bufs(hw);

shutdown_arq_out:
        iavf_release_spinlock(&hw->aq.arq_spinlock);
        return ret_code;
}

/**
 *  iavf_init_adminq - main initialization routine for Admin Queue
 *  @hw: pointer to the hardware structure
 *
 *  Prior to calling this function, drivers *MUST* set the following fields
 *  in the hw->aq structure:
 *     - hw->aq.num_asq_entries
 *     - hw->aq.num_arq_entries
 *     - hw->aq.arq_buf_size
 *     - hw->aq.asq_buf_size
 **/
enum iavf_status iavf_init_adminq(struct iavf_hw *hw)
{
        enum iavf_status ret_code;

        /* verify input for valid configuration */
        if ((hw->aq.num_arq_entries == 0) ||
            (hw->aq.num_asq_entries == 0) ||
            (hw->aq.arq_buf_size == 0) ||
            (hw->aq.asq_buf_size == 0)) {
                ret_code = IAVF_ERR_CONFIG;
                goto init_adminq_exit;
        }
        iavf_init_spinlock(&hw->aq.asq_spinlock);
        iavf_init_spinlock(&hw->aq.arq_spinlock);

        /* Set up register offsets */
        iavf_adminq_init_regs(hw);

        /* setup ASQ command write back timeout */
        hw->aq.asq_cmd_timeout = IAVF_ASQ_CMD_TIMEOUT;

        /* allocate the ASQ */
        ret_code = iavf_init_asq(hw);
        if (ret_code != IAVF_SUCCESS)
                goto init_adminq_destroy_spinlocks;

        /* allocate the ARQ */
        ret_code = iavf_init_arq(hw);
        if (ret_code != IAVF_SUCCESS)
                goto init_adminq_free_asq;

        /* success! */
        goto init_adminq_exit;

init_adminq_free_asq:
        iavf_shutdown_asq(hw);
init_adminq_destroy_spinlocks:
        iavf_destroy_spinlock(&hw->aq.asq_spinlock);
        iavf_destroy_spinlock(&hw->aq.arq_spinlock);

init_adminq_exit:
        return ret_code;
}

/**
 *  iavf_shutdown_adminq - shutdown routine for the Admin Queue
 *  @hw: pointer to the hardware structure
 **/
enum iavf_status iavf_shutdown_adminq(struct iavf_hw *hw)
{
        enum iavf_status ret_code = IAVF_SUCCESS;

        if (iavf_check_asq_alive(hw))
                iavf_aq_queue_shutdown(hw, true);

        iavf_shutdown_asq(hw);
        iavf_shutdown_arq(hw);
        iavf_destroy_spinlock(&hw->aq.asq_spinlock);
        iavf_destroy_spinlock(&hw->aq.arq_spinlock);

        return ret_code;
}

/**
 *  iavf_clean_asq - cleans Admin send queue
 *  @hw: pointer to the hardware structure
 *
 *  returns the number of free desc
 **/
u16 iavf_clean_asq(struct iavf_hw *hw)
{
        struct iavf_adminq_ring *asq = &(hw->aq.asq);
        struct iavf_asq_cmd_details *details;
        u16 ntc = asq->next_to_clean;
        struct iavf_aq_desc desc_cb;
        struct iavf_aq_desc *desc;

        desc = IAVF_ADMINQ_DESC(*asq, ntc);
        details = IAVF_ADMINQ_DETAILS(*asq, ntc);
        while (rd32(hw, hw->aq.asq.head) != ntc) {
                iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE,
                           "ntc %d head %d.\n", ntc, rd32(hw, hw->aq.asq.head));

                if (details->callback) {
                        IAVF_ADMINQ_CALLBACK cb_func =
                                        (IAVF_ADMINQ_CALLBACK)details->callback;
                        iavf_memcpy(&desc_cb, desc, sizeof(struct iavf_aq_desc),
                                    IAVF_DMA_TO_DMA);
                        cb_func(hw, &desc_cb);
                }
                iavf_memset(desc, 0, sizeof(*desc), IAVF_DMA_MEM);
                iavf_memset(details, 0, sizeof(*details), IAVF_NONDMA_MEM);
                ntc++;
                if (ntc == asq->count)
                        ntc = 0;
                desc = IAVF_ADMINQ_DESC(*asq, ntc);
                details = IAVF_ADMINQ_DETAILS(*asq, ntc);
        }

        asq->next_to_clean = ntc;

        return IAVF_DESC_UNUSED(asq);
}

/**
 *  iavf_asq_done - check if FW has processed the Admin Send Queue
 *  @hw: pointer to the hw struct
 *
 *  Returns true if the firmware has processed all descriptors on the
 *  admin send queue. Returns false if there are still requests pending.
 **/
bool iavf_asq_done(struct iavf_hw *hw)
{
        /* AQ designers suggest use of head for better
         * timing reliability than DD bit
         */
        return rd32(hw, hw->aq.asq.head) == hw->aq.asq.next_to_use;

}

/**
 *  iavf_asq_send_command - send command to Admin Queue
 *  @hw: pointer to the hw struct
 *  @desc: prefilled descriptor describing the command (non DMA mem)
 *  @buff: buffer to use for indirect commands
 *  @buff_size: size of buffer for indirect commands
 *  @cmd_details: pointer to command details structure
 *
 *  This is the main send command driver routine for the Admin Queue send
 *  queue.  It runs the queue, cleans the queue, etc
 **/
enum iavf_status iavf_asq_send_command(struct iavf_hw *hw,
                                struct iavf_aq_desc *desc,
                                void *buff, /* can be NULL */
                                u16  buff_size,
                                struct iavf_asq_cmd_details *cmd_details)
{
        enum iavf_status status = IAVF_SUCCESS;
        struct iavf_dma_mem *dma_buff = NULL;
        struct iavf_asq_cmd_details *details;
        struct iavf_aq_desc *desc_on_ring;
        bool cmd_completed = false;
        u16  retval = 0;
        u32  val = 0;

        iavf_acquire_spinlock(&hw->aq.asq_spinlock);

        hw->aq.asq_last_status = IAVF_AQ_RC_OK;

        if (hw->aq.asq.count == 0) {
                iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE,
                           "AQTX: Admin queue not initialized.\n");
                status = IAVF_ERR_QUEUE_EMPTY;
                goto asq_send_command_error;
        }

        val = rd32(hw, hw->aq.asq.head);
        if (val >= hw->aq.num_asq_entries) {
                iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE,
                           "AQTX: head overrun at %d\n", val);
                status = IAVF_ERR_QUEUE_EMPTY;
                goto asq_send_command_error;
        }

        details = IAVF_ADMINQ_DETAILS(hw->aq.asq, hw->aq.asq.next_to_use);
        if (cmd_details) {
                iavf_memcpy(details,
                            cmd_details,
                            sizeof(struct iavf_asq_cmd_details),
                            IAVF_NONDMA_TO_NONDMA);

                /* If the cmd_details are defined copy the cookie.  The
                 * CPU_TO_LE32 is not needed here because the data is ignored
                 * by the FW, only used by the driver
                 */
                if (details->cookie) {
                        desc->cookie_high =
                                CPU_TO_LE32(IAVF_HI_DWORD(details->cookie));
                        desc->cookie_low =
                                CPU_TO_LE32(IAVF_LO_DWORD(details->cookie));
                }
        } else {
                iavf_memset(details, 0,
                            sizeof(struct iavf_asq_cmd_details),
                            IAVF_NONDMA_MEM);
        }

        /* clear requested flags and then set additional flags if defined */
        desc->flags &= ~CPU_TO_LE16(details->flags_dis);
        desc->flags |= CPU_TO_LE16(details->flags_ena);

        if (buff_size > hw->aq.asq_buf_size) {
                iavf_debug(hw,
                           IAVF_DEBUG_AQ_MESSAGE,
                           "AQTX: Invalid buffer size: %d.\n",
                           buff_size);
                status = IAVF_ERR_INVALID_SIZE;
                goto asq_send_command_error;
        }

        if (details->postpone && !details->async) {
                iavf_debug(hw,
                           IAVF_DEBUG_AQ_MESSAGE,
                           "AQTX: Async flag not set along with postpone flag");
                status = IAVF_ERR_PARAM;
                goto asq_send_command_error;
        }

        /* call clean and check queue available function to reclaim the
         * descriptors that were processed by FW, the function returns the
         * number of desc available
         */
        /* the clean function called here could be called in a separate thread
         * in case of asynchronous completions
         */
        if (iavf_clean_asq(hw) == 0) {
                iavf_debug(hw,
                           IAVF_DEBUG_AQ_MESSAGE,
                           "AQTX: Error queue is full.\n");
                status = IAVF_ERR_ADMIN_QUEUE_FULL;
                goto asq_send_command_error;
        }

        /* initialize the temp desc pointer with the right desc */
        desc_on_ring = IAVF_ADMINQ_DESC(hw->aq.asq, hw->aq.asq.next_to_use);

        /* if the desc is available copy the temp desc to the right place */
        iavf_memcpy(desc_on_ring, desc, sizeof(struct iavf_aq_desc),
                    IAVF_NONDMA_TO_DMA);

        /* if buff is not NULL assume indirect command */
        if (buff != NULL) {
                dma_buff = &(hw->aq.asq.r.asq_bi[hw->aq.asq.next_to_use]);
                /* copy the user buff into the respective DMA buff */
                iavf_memcpy(dma_buff->va, buff, buff_size,
                            IAVF_NONDMA_TO_DMA);
                desc_on_ring->datalen = CPU_TO_LE16(buff_size);

                /* Update the address values in the desc with the pa value
                 * for respective buffer
                 */
                desc_on_ring->params.external.addr_high =
                                CPU_TO_LE32(IAVF_HI_DWORD(dma_buff->pa));
                desc_on_ring->params.external.addr_low =
                                CPU_TO_LE32(IAVF_LO_DWORD(dma_buff->pa));
        }

        /* bump the tail */
        iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE, "AQTX: desc and buffer:\n");
        iavf_debug_aq(hw, IAVF_DEBUG_AQ_COMMAND, (void *)desc_on_ring,
                      buff, buff_size);
        (hw->aq.asq.next_to_use)++;
        if (hw->aq.asq.next_to_use == hw->aq.asq.count)
                hw->aq.asq.next_to_use = 0;
        if (!details->postpone)
                wr32(hw, hw->aq.asq.tail, hw->aq.asq.next_to_use);

        /* if cmd_details are not defined or async flag is not set,
         * we need to wait for desc write back
         */
        if (!details->async && !details->postpone) {
                u32 total_delay = 0;

                do {
                        /* AQ designers suggest use of head for better
                         * timing reliability than DD bit
                         */
                        if (iavf_asq_done(hw))
                                break;
                        iavf_usec_delay(50);
                        total_delay += 50;
                } while (total_delay < hw->aq.asq_cmd_timeout);
        }

        /* if ready, copy the desc back to temp */
        if (iavf_asq_done(hw)) {
                iavf_memcpy(desc, desc_on_ring, sizeof(struct iavf_aq_desc),
                            IAVF_DMA_TO_NONDMA);
                if (buff != NULL)
                        iavf_memcpy(buff, dma_buff->va, buff_size,
                                    IAVF_DMA_TO_NONDMA);
                retval = LE16_TO_CPU(desc->retval);
                if (retval != 0) {
                        iavf_debug(hw,
                                   IAVF_DEBUG_AQ_MESSAGE,
                                   "AQTX: Command completed with error 0x%X.\n",
                                   retval);

                        /* strip off FW internal code */
                        retval &= 0xff;
                }
                cmd_completed = true;
                if ((enum iavf_admin_queue_err)retval == IAVF_AQ_RC_OK)
                        status = IAVF_SUCCESS;
                else if ((enum iavf_admin_queue_err)retval == IAVF_AQ_RC_EBUSY)
                        status = IAVF_ERR_NOT_READY;
                else
                        status = IAVF_ERR_ADMIN_QUEUE_ERROR;
                hw->aq.asq_last_status = (enum iavf_admin_queue_err)retval;
        }

        iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE,
                   "AQTX: desc and buffer writeback:\n");
        iavf_debug_aq(hw, IAVF_DEBUG_AQ_COMMAND, (void *)desc, buff, buff_size);

        /* save writeback aq if requested */
        if (details->wb_desc)
                iavf_memcpy(details->wb_desc, desc_on_ring,
                            sizeof(struct iavf_aq_desc), IAVF_DMA_TO_NONDMA);

        /* update the error if time out occurred */
        if ((!cmd_completed) &&
            (!details->async && !details->postpone)) {
                if (rd32(hw, hw->aq.asq.len) & IAVF_VF_ATQLEN1_ATQCRIT_MASK) {
                        iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE,
                                   "AQTX: AQ Critical error.\n");
                        status = IAVF_ERR_ADMIN_QUEUE_CRITICAL_ERROR;
                } else {
                        iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE,
                                   "AQTX: Writeback timeout.\n");
                        status = IAVF_ERR_ADMIN_QUEUE_TIMEOUT;
                }
        }

asq_send_command_error:
        iavf_release_spinlock(&hw->aq.asq_spinlock);
        return status;
}

/**
 *  iavf_fill_default_direct_cmd_desc - AQ descriptor helper function
 *  @desc:     pointer to the temp descriptor (non DMA mem)
 *  @opcode:   the opcode can be used to decide which flags to turn off or on
 *
 *  Fill the desc with default values
 **/
void iavf_fill_default_direct_cmd_desc(struct iavf_aq_desc *desc,
                                       u16 opcode)
{
        /* zero out the desc */
        iavf_memset((void *)desc, 0, sizeof(struct iavf_aq_desc),
                    IAVF_NONDMA_MEM);
        desc->opcode = CPU_TO_LE16(opcode);
        desc->flags = CPU_TO_LE16(IAVF_AQ_FLAG_SI);
}

/**
 *  iavf_clean_arq_element
 *  @hw: pointer to the hw struct
 *  @e: event info from the receive descriptor, includes any buffers
 *  @pending: number of events that could be left to process
 *
 *  This function cleans one Admin Receive Queue element and returns
 *  the contents through e.  It can also return how many events are
 *  left to process through 'pending'
 **/
enum iavf_status iavf_clean_arq_element(struct iavf_hw *hw,
                                             struct iavf_arq_event_info *e,
                                             u16 *pending)
{
        enum iavf_status ret_code = IAVF_SUCCESS;
        u16 ntc = hw->aq.arq.next_to_clean;
        struct iavf_aq_desc *desc;
        struct iavf_dma_mem *bi;
        u16 desc_idx;
        u16 datalen;
        u16 flags;
        u16 ntu;

        /* pre-clean the event info */
        iavf_memset(&e->desc, 0, sizeof(e->desc), IAVF_NONDMA_MEM);

        /* take the lock before we start messing with the ring */
        iavf_acquire_spinlock(&hw->aq.arq_spinlock);

        if (hw->aq.arq.count == 0) {
                iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE,
                           "AQRX: Admin queue not initialized.\n");
                ret_code = IAVF_ERR_QUEUE_EMPTY;
                goto clean_arq_element_err;
        }

        /* set next_to_use to head */
        ntu = rd32(hw, hw->aq.arq.head) & IAVF_VF_ARQH1_ARQH_MASK;
        if (ntu == ntc) {
                /* nothing to do - shouldn't need to update ring's values */
                ret_code = IAVF_ERR_ADMIN_QUEUE_NO_WORK;
                goto clean_arq_element_out;
        }

        /* now clean the next descriptor */
        desc = IAVF_ADMINQ_DESC(hw->aq.arq, ntc);
        desc_idx = ntc;

        hw->aq.arq_last_status =
                (enum iavf_admin_queue_err)LE16_TO_CPU(desc->retval);
        flags = LE16_TO_CPU(desc->flags);
        if (flags & IAVF_AQ_FLAG_ERR) {
                ret_code = IAVF_ERR_ADMIN_QUEUE_ERROR;
                iavf_debug(hw,
                           IAVF_DEBUG_AQ_MESSAGE,
                           "AQRX: Event received with error 0x%X.\n",
                           hw->aq.arq_last_status);
        }

        iavf_memcpy(&e->desc, desc, sizeof(struct iavf_aq_desc),
                    IAVF_DMA_TO_NONDMA);
        datalen = LE16_TO_CPU(desc->datalen);
        e->msg_len = min(datalen, e->buf_len);
        if (e->msg_buf != NULL && (e->msg_len != 0))
                iavf_memcpy(e->msg_buf,
                            hw->aq.arq.r.arq_bi[desc_idx].va,
                            e->msg_len, IAVF_DMA_TO_NONDMA);

        iavf_debug(hw, IAVF_DEBUG_AQ_MESSAGE, "AQRX: desc and buffer:\n");
        iavf_debug_aq(hw, IAVF_DEBUG_AQ_COMMAND, (void *)desc, e->msg_buf,
                      hw->aq.arq_buf_size);

        /* Restore the original datalen and buffer address in the desc,
         * FW updates datalen to indicate the event message
         * size
         */
        bi = &hw->aq.arq.r.arq_bi[ntc];
        iavf_memset((void *)desc, 0, sizeof(struct iavf_aq_desc), IAVF_DMA_MEM);

        desc->flags = CPU_TO_LE16(IAVF_AQ_FLAG_BUF);
        if (hw->aq.arq_buf_size > IAVF_AQ_LARGE_BUF)
                desc->flags |= CPU_TO_LE16(IAVF_AQ_FLAG_LB);
        desc->datalen = CPU_TO_LE16((u16)bi->size);
        desc->params.external.addr_high = CPU_TO_LE32(IAVF_HI_DWORD(bi->pa));
        desc->params.external.addr_low = CPU_TO_LE32(IAVF_LO_DWORD(bi->pa));

        /* set tail = the last cleaned desc index. */
        wr32(hw, hw->aq.arq.tail, ntc);
        /* ntc is updated to tail + 1 */
        ntc++;
        if (ntc == hw->aq.num_arq_entries)
                ntc = 0;
        hw->aq.arq.next_to_clean = ntc;
        hw->aq.arq.next_to_use = ntu;

clean_arq_element_out:
        /* Set pending if needed, unlock and return */
        if (pending != NULL)
                *pending = (ntc > ntu ? hw->aq.arq.count : 0) + (ntu - ntc);
clean_arq_element_err:
        iavf_release_spinlock(&hw->aq.arq_spinlock);

        return ret_code;
}